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Sample records for adipogenic acetyltransferase tip60

  1. The adipogenic acetyltransferase Tip60 targets activation function 1 of peroxisome proliferator-activated receptor gamma

    DEFF Research Database (Denmark)

    van Beekum, Olivier; Brenkman, Arjan B; Grøntved, Lars;

    2008-01-01

    The transcription factor peroxisome proliferator-activated receptor gamma (PPARgamma) plays a key role in the regulation of lipid and glucose metabolism in adipocytes, by regulating their differentiation, maintenance, and function. The transcriptional activity of PPARgamma is dictated by the set...... of proteins with which this nuclear receptor interacts under specific conditions. Here we identify the HIV-1 Tat-interacting protein 60 (Tip60) as a novel positive regulator of PPARgamma transcriptional activity. Using tandem mass spectrometry, we found that PPARgamma and the acetyltransferase Tip60 interact...

  2. Rational design and validation of a Tip60 histone acetyltransferase inhibitor

    Science.gov (United States)

    Gao, Chunxia; Bourke, Emer; Scobie, Martin; Famme, Melina Arcos; Koolmeister, Tobias; Helleday, Thomas; Eriksson, Leif A.; Lowndes, Noel F.; Brown, James A. L.

    2014-06-01

    Histone acetylation is required for many aspects of gene regulation, genome maintenance and metabolism and dysfunctional acetylation is implicated in numerous diseases, including cancer. Acetylation is regulated by histone acetyltransferases (HATs) and histone deacetylases and currently, few general HAT inhibitors have been described. We identified the HAT Tip60 as an excellent candidate for targeted drug development, as Tip60 is a key mediator of the DNA damage response and transcriptional co-activator. Our modeling of Tip60 indicated that the active binding pocket possesses opposite charges at each end, with the positive charges attributed to two specific side chains. We used structure based drug design to develop a novel Tip60 inhibitor, TH1834, to fit this specific pocket. We demonstrate that TH1834 significantly inhibits Tip60 activity in vitro and treating cells with TH1834 results in apoptosis and increased unrepaired DNA damage (following ionizing radiation treatment) in breast cancer but not control cell lines. Furthermore, TH1834 did not affect the activity of related HAT MOF, as indicated by H4K16Ac, demonstrating specificity. The modeling and validation of the small molecule inhibitor TH1834 represents a first step towards developing additional specific, targeted inhibitors of Tip60 that may lead to further improvements in the treatment of breast cancer.

  3. Tip60 HAT Action Mediates Environmental Enrichment Induced Cognitive Restoration.

    Science.gov (United States)

    Xu, Songjun; Panikker, Priyalakshmi; Iqbal, Sahira; Elefant, Felice

    2016-01-01

    Environmental enrichment (EE) conditions have beneficial effects for reinstating cognitive ability in neuropathological disorders like Alzheimer's disease (AD). While EE benefits involve epigenetic gene control mechanisms that comprise histone acetylation, the histone acetyltransferases (HATs) involved remain largely unknown. Here, we examine a role for Tip60 HAT action in mediating activity- dependent beneficial neuroadaptations to EE using the Drosophila CNS mushroom body (MB) as a well-characterized cognition model. We show that flies raised under EE conditions display enhanced MB axonal outgrowth, synaptic marker protein production, histone acetylation induction and transcriptional activation of cognition linked genes when compared to their genotypically identical siblings raised under isolated conditions. Further, these beneficial changes are impaired in both Tip60 HAT mutant flies and APP neurodegenerative flies. While EE conditions provide some beneficial neuroadaptive changes in the APP neurodegenerative fly MB, such positive changes are significantly enhanced by increasing MB Tip60 HAT levels. Our results implicate Tip60 as a critical mediator of EE-induced benefits, and provide broad insights into synergistic behavioral and epigenetic based therapeutic approaches for treatment of cognitive disorder. PMID:27454757

  4. Deficiency of DNA double-strand break repair and enhanced radiosensitivity in Tip60 silenced cells

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of Tip60 on the cellular radiosensitivity,and to explore the related mechanism. Methods: siRNA and anacardic acid (AA, an inhibitor of Tip60 acetyltransferase) were used to inhibit Tip60 expression and its acetyltransferase activity, respectively. Radiosensitivity was analyzed by colony-forming ability assay. γ-H2AX foci were detected to analyze the DNA double-strand break (DSB). Immunoprecipitation was used to determine the interaction of proteins. Results: siRNA-mediated silencing of Tip60 led to enhanced sensitivity of U2OS cells at 1, 2 Gy after γ-ray irradiation, but had no significant effect at 4 Gy post-irradiation (t=3.364, 3.979, P<0.05).γ-H2AX foci detection indicated that Tip60 silencing resulted in a decreased capability of DNA double-strand break repair at 1, 4 and 8 h after irradiation (t=3.875, 3.183 and 3.175, respectively, P<0.05). The interaction of Tip60 and DNA-PKcs was prompted by ionizing radiation. Anacardic acid largely abrogated the phosphorylation of DNA-PKcs at T2609 site induced by irradiation. Conclusions: Tip60 plays a role in the cellular response to ionizing radiation-induced DNA damage through, at least in part, interacting with DNA-PKcs and regulating its phosphorylation. (authors)

  5. FOXP3 interactions with histone acetyltransferase and class II histone deacetylases are required for repression.

    Science.gov (United States)

    Li, Bin; Samanta, Arabinda; Song, Xiaomin; Iacono, Kathryn T; Bembas, Kathryn; Tao, Ran; Basu, Samik; Riley, James L; Hancock, Wayne W; Shen, Yuan; Saouaf, Sandra J; Greene, Mark I

    2007-03-13

    The forkhead family protein FOXP3 acts as a repressor of transcription and is both an essential and sufficient regulator of the development and function of regulatory T cells. The molecular mechanism by which FOXP3-mediated transcriptional repression occurs remains unclear. Here, we report that transcriptional repression by FOXP3 involves a histone acetyltransferase-deacetylase complex that includes histone acetyltransferase TIP60 (Tat-interactive protein, 60 kDa) and class II histone deacetylases HDAC7 and HDAC9. The N-terminal 106-190 aa of FOXP3 are required for TIP60-FOXP3, HDAC7-FOXP3 association, as well as for the transcriptional repression of FOXP3 via its forkhead domain. FOXP3 can be acetylated in primary human regulatory T cells, and TIP60 promotes FOXP3 acetylation in vivo. Overexpression of TIP60 but not its histone acetyltransferase-deficient mutant promotes, whereas knockdown of endogenous TIP60 relieved, FOXP3-mediated transcriptional repression. A minimum FOXP3 ensemble containing native TIP60 and HDAC7 is necessary for IL-2 production regulation in T cells. Moreover, FOXP3 association with HDAC9 is antagonized by T cell stimulation and can be restored by the protein deacetylation inhibitor trichostatin A, indicating a complex dynamic aspect of T suppressor cell regulation. These findings identify a previously uncharacterized complex-based mechanism by which FOXP3 actively mediates transcriptional repression. PMID:17360565

  6. The effects of over-expressing Tip60 on cellular DNA damage repair and cell cycle progression

    International Nuclear Information System (INIS)

    To investigate the effects of Tip60 on DNA damage repair, cell cycle and the related mechanism as well, the proliferative activity, DNA double strand break (DSB) repair competency and cell cycle arrest were analyzed in stable Tip60-overexpression U2OS cells established by transfecting with exogenous Tip60 gene. It was found that the overexpression of Tip60 inhibited the proliferative activity but increased the DNA damage repair competency. The radiation-induced G2/M arrest was prolonged in Tip60 over-expressed U2OS cells, which was associated with a decreasing level of cell cycle checkpoint protein Cyclin B/CDC2 complex. (authors)

  7. SMCX and components of the TIP60 complex contribute to E2 regulation of the HPV E6/E7 promoter

    Science.gov (United States)

    Smith, Jennifer A.; Haberstroh, Friederike S.; White, Elizabeth A.; Livingston, David M.; DeCaprio, James A.; Howley, Peter M.

    2014-01-01

    An important step in the malignant progression of HPV-associated lesions is the dysregulation of expression of the viral E6 and E7 oncogenes. This is often achieved through the loss of expression of E2, which represses the HPV LCR promoter and E6/E7 expression. Our previous studies confirmed a role for Brd4 in mediating the E2 transcriptional repression function, and identified JARID1C/SMCX and EP400 as contributors to E2-mediated repression. Here we show that TIP60, a component of the TIP60/TRRAP histone acetyltransferase complex, also contributes to the E2 repression function, and we extend our studies on SMCX. Di- and tri-methyl marks on histone H3K4 are reduced in the presence of E2 and SMCX, suggesting a mechanism by which SMCX contributes to E2-mediated repression of the HPV LCR. Together, these findings lead us to hypothesize that E2 recruits histone-modifying cellular proteins to the HPV LCR, resulting in transcriptional repression of E6 and E7. PMID:25222147

  8. SMCX and components of the TIP60 complex contribute to E2 regulation of the HPV E6/E7 promoter.

    Science.gov (United States)

    Smith, Jennifer A; Haberstroh, Friederike S; White, Elizabeth A; Livingston, David M; DeCaprio, James A; Howley, Peter M

    2014-11-01

    An important step in the malignant progression of HPV-associated lesions is the dysregulation of expression of the viral E6 and E7 oncogenes. This is often achieved through the loss of expression of E2, which represses the HPV LCR promoter and E6/E7 expression. Our previous studies confirmed a role for Brd4 in mediating the E2 transcriptional repression function, and identified JARID1C/SMCX and EP400 as contributors to E2-mediated repression. Here we show that TIP60, a component of the TIP60/TRRAP histone acetyltransferase complex, also contributes to the E2 repression function, and we extend our studies on SMCX. Di- and tri-methyl marks on histone H3K4 are reduced in the presence of E2 and SMCX, suggesting a mechanism by which SMCX contributes to E2-mediated repression of the HPV LCR. Together, these findings lead us to hypothesize that E2 recruits histone-modifying cellular proteins to the HPV LCR, resulting in transcriptional repression of E6 and E7. PMID:25222147

  9. MDR1 mediated chemoresistance: BMI1 and TIP60 in action.

    Science.gov (United States)

    Banerjee Mustafi, Soumyajit; Chakraborty, Prabir Kumar; Naz, Sarwat; Dwivedi, Shailendra Kumar Dhar; Street, Mark; Basak, Rumki; Yang, Da; Ding, Kai; Mukherjee, Priyabrata; Bhattacharya, Resham

    2016-08-01

    Chemotherapy-induced emergence of drug resistant cells is frequently observed and is exemplified by the expression of family of drug resistance proteins including, multidrug resistance protein 1 (MDR1). However, a concise mechanism for chemotherapy-induced MDR1 expression is unclear. Mechanistically, mutational selection, epigenetic alteration, activation of the Wnt pathway or impaired p53 function have been implicated. The present study describes that the surviving fraction of cisplatin resistant cells co- upregulate MDR1, BMI1 and acetyl transferase activity of TIP60. Using complementary gain and loss of function approaches, we demonstrate that the expression of MDR1 is positively regulated by BMI1, a stem-cell factor classically known as a transcriptional repressor. Our study establishes a functional interaction between TIP60 and BMI-1 resulting in upregulation of MDR1 expression. Chromatin immunoprecipitation (ChIP) assays further establish that the proximal MDR1 promoter responds to cisplatin in a BMI1 dependent manner. BMI1 interacts with a cluster of E-box elements on the MDR1 promoter and recruits TIP60 resulting in acetylation of histone H2A and H3. Collectively, our data establish a hitherto unknown liaison among MDR1, BMI1 and TIP60 and provide mechanistic insights into cisplatin-induced MDR1 expression resulting in acquired cross-resistance against paclitaxel, doxorubicin and likely other drugs. In conclusion, our results advocate utilizing anti-BMI1 strategies to alleviate acquired resistance to chemotherapy. PMID:27295567

  10. 6-alkylsalicylates are selective Tip60 inhibitors and target the acetyl-CoA binding site

    NARCIS (Netherlands)

    Ghizzoni, Massimo; Wu, Jiang; Gao, Tielong; Haisma, Hidde J.; Dekker, Frank J.; Zheng, Y. George

    2012-01-01

    Histone acetyltransferases are important enzymes that regulate various cellular functions, such as epigenetic control of DNA transcription. Development of HAT inhibitors with high selectivity and potency will provide powerful mechanistic tools for the elucidation of the biological functions of HATs

  11. FOXP3 interactions with histone acetyltransferase and class II histone deacetylases are required for repression

    OpenAIRE

    Li, Bin; Samanta, Arabinda; Song, Xiaomin; Iacono, Kathryn T.; Bembas, Kathryn; Tao, Ran; Basu, Samik; Riley, James L.; Hancock, Wayne W.; Shen, Yuan; Saouaf, Sandra J.; Greene, Mark I.

    2007-01-01

    The forkhead family protein FOXP3 acts as a repressor of transcription and is both an essential and sufficient regulator of the development and function of regulatory T cells. The molecular mechanism by which FOXP3-mediated transcriptional repression occurs remains unclear. Here, we report that transcriptional repression by FOXP3 involves a histone acetyltransferase–deacetylase complex that includes histone acetyltransferase TIP60 (Tat-interactive protein, 60 kDa) and class II histone deacety...

  12. SMCX and components of the TIP60 complex contribute to E2 regulation of the HPV E6/E7 promoter

    OpenAIRE

    Smith, Jennifer A.; Haberstroh, Friederike S.; White, Elizabeth A.; Livingston, David M.; DeCaprio, James A.; Howley, Peter M.

    2014-01-01

    An important step in the malignant progression of HPV-associated lesions is the dysregulation of expression of the viral E6 and E7 oncogenes. This is often achieved through the loss of expression of E2, which represses the HPV LCR promoter and E6/E7 expression. Our previous studies confirmed a role for Brd4 in mediating the E2 transcriptional repression function, and identified JARID1C/SMCX and EP400 as contributors to E2-mediated repression. Here we show that TIP60, a component of the TIP60/...

  13. Expression Analysis of cPLA2 Alpha Interacting TIP60 in Diabetic KKAy and Non-Diabetic C57BL Wild-Type Mice: No Impact of Transient and Stable TIP60 Overexpression on Glucose-Stimulated Insulin Secretion in Pancreatic Beta-Cells

    DEFF Research Database (Denmark)

    Nordentoft, Iver; Jeppesen, Per B; Nielsen, Anders L;

    2007-01-01

    that TIP60 plays a regulatory role in glucose-stimulated insulin secretion from pancreatic beta-cells. MATERIAL AND METHODS: Ten obese diabetic KKAy mice and ten non-diabetic C57BL mice were fed a standard chow diet. After nine weeks, islet RNA was purified and used to measure TIP60 expression. We......In the present study we investigate the expression levels of cytosolic phospholipase A2 alpha (cPLA2alpha) interacting histone acetyl transferase proteins TIP60alpha and TIP60beta in non-diabetic C57BL wild-type mice and obese type 2 diabetic KKAy model mice. The aim was to test our hypothesis...... investigated the effect of TIP60alpha and TIP60beta on glucose-stimulated insulin secretion by transient and stable overexpression in the pancreatic mouse beta-cell line MIN6 and the rat beta-cell line INS-1E. RESULTS: We found that non-diabetic C57BL mice and diabetic KKAy mice have the same level of both...

  14. The Functional Analysis of Histone Acetyltransferase MOF in Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Jiaming Su

    2016-01-01

    Full Text Available Changes in chromatin structure and heritably regulating the gene expression by epigenetic mechanisms, such as histone post-translational modification, are involved in most cellular biological processes. Thus, abnormal regulation of epigenetics is implicated in the occurrence of various diseases, including cancer. Human MOF (males absent on the first is a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60 family of histone acetyltransferases (HATs. As a catalytic subunit, MOF can form at least two distinct multiprotein complexes (MSL and NSL in human cells. Both complexes can acetylate histone H4 at lysine 16 (H4K16; however, the NSL complex possesses broader substrate specificity and can also acetylate histone H4 at lysines 5 and 8 (H4K5 and H4K8, suggesting the complexity of the intracellular functions of MOF. Silencing of MOF in cells leads to genomic instability, inactivation of gene transcription, defective DNA damage repair and early embryonic lethality. Unbalanced MOF expression and its corresponding acetylation of H4K16 have been found in certain primary cancer tissues, including breast cancer, medulloblastoma, ovarian cancer, renal cell carcinoma, colorectal carcinoma, gastric cancer, as well as non-small cell lung cancer. In this review, we provide a brief overview of MOF and its corresponding histone acetylation, introduce recent research findings that link MOF functions to tumorigenesis and speculate on the potential role that may be relevant to tumorigenic pathways.

  15. Regulation of the histone acetyltransferase activity of hMOF via autoacetylation of Lys274

    Institute of Scientific and Technical Information of China (English)

    Bingfa Sun; Shunling Guo; Qingyu Tang; Chen Li; Rong Zeng; Zhiqi Xiong; Chen Zhong; Jianping Ding

    2011-01-01

    Dear Editor, Males-absent-on-the-first (MOF, also called MYST1 or KAT8) is a histone acetyltransferase (HAT) belonging to the MOZ, Ybf2/Sas3, Sas2 and Tip60 (MYST) family.MOF has been shown to possess a specific HAT activity towards Lysl6 of histone H4 (H4K16) [1].Homozygous knockout of MOF in mice results in loss of H4K16 acetylation and embryonic lethality, indicating that MOF and H4K16 acetylation are essential for embryogenesis and genome stability in mammals [2].Downregulation of human MOF (hMOF) leads to dramatic nuclear morphological deformation and inhibition of cell cycle progression [3], and has recently been correlated with primary breast carcinoma and medulloblastoma [4].

  16. Zfp423 promotes adipogenic differentiation of bovine stromal vascular cells.

    Directory of Open Access Journals (Sweden)

    Yan Huang

    Full Text Available Intramuscular fat or marbling is critical for the palatability of beef. In mice, very recent studies show that adipocytes and fibroblasts share a common pool of progenitor cells, with Zinc finger protein 423 (Zfp423 as a key initiator of adipogenic differentiation. To evaluate the role of Zfp423 in intramuscular adipogenesis and marbling in beef cattle, we sampled beef muscle for separation of stromal vascular cells. These cells were immortalized with pCI neo-hEST2 and individual clones were selected by G418. A total of 288 clones (3×96 well plates were isolated and induced to adipogenesis. The presence of adipocytes was assessed by Oil-Red-O staining. Three clones with high and low adipogenic potential respectively were selected for further analyses. In addition, fibro/adipogenic progenitor cells were selected using a surface marker, platelet derived growth factor receptor (PDGFR α. The expression of Zfp423 was much higher (307.4±61.9%, P<0.05 in high adipogenic cells, while transforming growth factor (TGF-β was higher (156.1±48.7%, P<0.05 in low adipogenic cells. Following adipogenic differentiation, the expression of peroxisome proliferator-activated receptor γ (PPARγ and CCAAT/enhancer binding protein α (C/EBPα were much higher (239.4±84.1% and 310.7±138.4%, respectively, P<0.05 in high adipogenic cells. Over-expression of Zfp423 in stromal vascular cells and cloned low adipogenic cells dramatically increased their adipogenic differentiation, accompanied with the inhibition of TGF-β expression. Zfp423 knockdown by shRNA in high adipogenic cells largely prevented their adipogenic differentiation. The differential regulation of Zfp423 and TGF-β between low and high adipogenic cells is associated with the DNA methylation in their promoters. In conclusion, data show that Zfp423 is a critical regulator of adipogenesis in stromal vascular cells of bovine muscle, and Zfp423 may provide a molecular target for enhancing intramuscular

  17. Insulin Cannot Induce Adipogenic Differentiation in Primary Cardiac Cultures.

    Science.gov (United States)

    Parameswaran, Sreejit; Sharma, Rajendra K

    2016-09-01

    Cardiac tissue contains a heterogeneous population of cardiomyocytes and nonmyocyte population especially fibroblasts. Fibroblast differentiation into adipogenic lineage is important for fat accumulation around the heart which is important in cardiac pathology. The differentiation in fibroblast has been observed both spontaneously and due to increased insulin stimulation. The present study aims to observe the effect of insulin in adipogenic differentiation of cardiac cells present in primary murine cardiomyocyte cultures. Oil Red O (ORO) staining has been used for observing the lipid accumulations formed due to adipogenic differentiation in murine cardiomyocyte cultures. The accumulated lipids were quantified by ORO assay and normalized using protein estimation. The lipid accumulation in cardiac cultures did not increase in presence of insulin. However, addition of other growth factors like insulin-like growth factor 1 and epidermal growth factor promoted adipogenic differentiation even in the presence of insulin and other inhibitory molecules such as vitamins. Lipid accumulation also increased in cells grown in media without insulin after an initial exposure to insulin-containing growth media. The current study adds to the existing knowledge that the insulin by itself cannot induce adipogenic induction in the cardiac cultures. The data have significance in the understanding of cardiovascular health especially in diabetic patients. PMID:27574386

  18. Phenamil enhances the adipogenic differentiation of hen preadipocytes.

    Science.gov (United States)

    Regassa, Alemu; Park, Kye Won; Kim, Woo Kyun

    2016-10-01

    A study was conducted to examine the effect of phenamil on adipogenic differentiation and expression of key adipogenic transcripts in hen preadipocytes. Preadipocytes were isolated from 20-week old Single Comb White Leghorn hens (Gallas gallus, Lohman strain). The experiment lasted for 48 h and had six treatments. Non-treated control (C) cells, cells treated with dexamethasone, 3-isobutyl-1-methylxanthine, insulin, and oleic acid (DMIOA) (T1), DMIOA + 15 μM phenamil (T2), DMIOA + 30 μM phenamil (T3), 15 μM phenamil alone (T4), and 30 μM phenamil alone (T5). Neutral lipid accumulation and the mRNA expression of key adipogenic transcripts were measured in all treatments and compared. Lipid accumulation was detected in T1, T2, and T3 only. Expression of peroxisome proliferator receptor-activator gamma 2 (PPARγ2), the core enhancer binding protein α (C/EBPα), C/EBPβ, fatty acid binding protein 4 (FABP4), and lipoprotein lipase (LPL) as well as ETS variant 4 (ETV4) and 5 was higher (P hen preadipocytes but does not induce adipogenesis by itself. PMID:27460177

  19. Enzyme kinetics and inhibition of histone acetyltransferase KAT8

    NARCIS (Netherlands)

    Wapenaar, Hannah; van der Wouden, Petra E; Groves, Matthew R; Rotili, Dante; Mai, Antonello; Dekker, Frank J

    2015-01-01

    Lysine acetyltransferase 8 (KAT8) is a histone acetyltransferase (HAT) responsible for acetylating lysine 16 on histone H4 (H4K16) and plays a role in cell cycle progression as well as acetylation of the tumor suppressor protein p53. Further studies on its biological function and drug discovery init

  20. cAMP-dependent signaling regulates the adipogenic effect of n-6 polyunsaturated fatty acids

    NARCIS (Netherlands)

    Madsen, L.; Pedersen, L.M.; Liaset, B.; Ma, T.; Petersen, R.K.; Berg, S. van den; Pan, J.; Müller-Decker, K.M.; Dülsner, E.D.; Kleemann, R.; Kooistra, T.; Døskeland, S.O.; Kristiansen, K.

    2008-01-01

    The effect of n-6 polyunsaturated fatty acids (n-6 PUFAs) on adipogenesis and obesity is controversial. Using in vitro cell culture models, we show that n-6 PUFAs was pro-adipogenic under conditions with base-line levels of cAMP, but anti-adipogenic when the levels of cAMP were elevated. The anti-ad

  1. Fibroblast growth factor-2 stimulates adipogenic differentiation of human adipose-derived stem cells

    International Nuclear Information System (INIS)

    Adipose-derived stem cells (ASCs) have demonstrated a capacity for differentiating into a variety of lineages, including bone, cartilage, or fat, depending on the inducing stimuli and specific growth and factors. It is acknowledged that fibroblast growth factor-2 (FGF-2) promotes chondrogenic and inhibits osteogenic differentiation of ASCs, but thorough investigations of its effects on adipogenic differentiation are lacking. In this study, we demonstrate at the cellular and molecular levels the effect of FGF-2 on adipogenic differentiation of ASCs, as induced by an adipogenic hormonal cocktail consisting of 3-isobutyl-1-methylxanthine (IBMX), dexamethasone, insulin, and indomethacin. FGF-2 significantly enhances the adipogenic differentiation of human ASCs. Furthermore, in cultures receiving FGF-2 before adipogenic induction, mRNA expression of peroxisome proliferator-activated receptor γ2 (PPARγ2), a key transcription factor in adipogenesis, was upregulated. The results of FGF-2 supplementation suggest the potential applications of FGF-2 and ASCs in adipose tissue regeneration

  2. Hypoxia induces adipogenic differentitation of myoblastic cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Itoigawa, Yoshiaki [Tohoku University School of Medicine, Sendai (Japan); Juntendo University School of Medicine, Tokyo (Japan); Kishimoto, Koshi N., E-mail: kishimoto@med.tohoku.ac.jp [Tohoku University School of Medicine, Sendai (Japan); Okuno, Hiroshi; Sano, Hirotaka [Tohoku University School of Medicine, Sendai (Japan); Kaneko, Kazuo [Juntendo University School of Medicine, Tokyo (Japan); Itoi, Eiji [Tohoku University School of Medicine, Sendai (Japan)

    2010-09-03

    Research highlights: {yields} C2C12 and G8 myogenic cell lines treated by hypoxia differentiate into adipocytes. {yields} The expression of C/EBP{beta}, {alpha} and PPAR{gamma} were increased under hypoxia. {yields} Myogenic differentiation of C2C12 was inhibited under hypoxia. -- Abstract: Muscle atrophy usually accompanies fat accumulation in the muscle. In such atrophic conditions as back muscles of kyphotic spine and the rotator cuff muscles with torn tendons, blood flow might be diminished. It is known that hypoxia causes trans-differentiation of mesenchymal stem cells derived from bone marrow into adipocytes. However, it has not been elucidated yet if hypoxia turned myoblasts into adipocytes. We investigated adipogenesis in C2C12 and G8 murine myogenic cell line treated by hypoxia. Cells were also treated with the cocktail of insulin, dexamethasone and IBMX (MDI), which has been known to inhibit Wnt signaling and promote adipogenesis. Adipogenic differentiation was seen in both hypoxia and MDI. Adipogenic marker gene expression was assessed in C2C12. CCAAT/enhancer-binding protein (C/EBP) {beta}, {alpha} and peroxisome proliferator activating receptor (PPAR) {gamma} were increased by both hypoxia and MDI. The expression profile of Wnt10b was different between hypoxia and MDI. The mechanism for adipogenesis of myoblasts in hypoxia might be regulated by different mechanism than the modification of Wnt signaling.

  3. cAMP-dependent signaling regulates the adipogenic effect of n-6 polyunsaturated fatty acids

    DEFF Research Database (Denmark)

    Madsen, Lise; Pedersen, Lone Møller; Liaset, Bjørn;

    2008-01-01

    The effect of n-6 polyunsaturated fatty acids (n-6 PUFAs) on adipogenesis and obesity is controversial. Using in vitro cell culture models, we show that n-6 PUFAs was pro-adipogenic under conditions with base-line levels of cAMP, but anti-adipogenic when the levels of cAMP were elevated. The anti...... pivotal in regulating the adipogenic effect of n-6 PUFAs and that diet-induced differences in cAMP levels may explain the ability of n-6 PUFAs to either enhance or counteract adipogenesis and obesity....

  4. Rapid quantitative assay for chloramphenicol acetyltransferase

    International Nuclear Information System (INIS)

    Measuring the expression of exogenous genetic material in mammalian cells is commonly done by fusing the DNA of interest to a gene encoding an easily-detected enzyme. Chloramphenicol acetyltransferase(CAT) is a convenient marker because it is not normally found in eukaryotes. CAT activity has usually been detected using a thin-layer chromatographic separation followed by autoradiography. An organic solvent extraction-based method for CAT detection has also been described, as well as a procedure utilizing HPLC analysis. Building on the extraction technique, they developed a rapid sensitive kinetic method for measuring CAT activity in cell homogenates. The method exploits the differential organic solubility of the substrate ([3H] or [14C]acetyl CoA) and the product (labeled acetylchloramphenicol). The assay is a simple one-vial, two-phase procedure and requires no tedious manipulations after the initial setup. Briefly, a 0.25 ml reaction with 100mM Tris-HCL, 1mM chloramphenicol, 0.1mM [14C]acetyl CoA and variable amounts of cell homogenate is pipetted into a miniscintillation vial, overlaid with 5 ml of a water-immiscible fluor, and incubated at 370C. At suitable intervals the vial is counted and the CAT level is quantitatively determined as the rate of increase in counts/min of the labeled product as it diffuses into the fluor phase, compared to a standard curve. When used to measure CAT in transfected Balb 3T3 cells the method correlated well with the other techniques

  5. Endocrine disrupting chemicals affect the adipogenic differentiation of mesenchymal stem cells in distinct ontogenetic windows

    Energy Technology Data Exchange (ETDEWEB)

    Biemann, Ronald, E-mail: ronald.biemann@medizin.uni-halle.de [Department of Anatomy and Cell Biology, Martin Luther University, Faculty of Medicine, Halle (Germany); Navarrete Santos, Anne [Department of Anatomy and Cell Biology, Martin Luther University, Faculty of Medicine, Halle (Germany); Navarrete Santos, Alexander [Department of Cardiothoracic Surgery, Martin Luther University, Faculty of Medicine, Halle (Germany); Riemann, Dagmar [Department of Immunology, Martin Luther University, Faculty of Medicine, Halle (Germany); Knelangen, Julia [Department of Anatomy and Cell Biology, Martin Luther University, Faculty of Medicine, Halle (Germany); Blueher, Matthias [Department of Medicine, University of Leipzig, Leipzig (Germany); Koch, Holger [Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Ruhr-University Bochum, Bochum (Germany); Fischer, Bernd [Department of Anatomy and Cell Biology, Martin Luther University, Faculty of Medicine, Halle (Germany)

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer Endocrine disrupting chemicals affect adipogenesis in mesenchymal stem cells (MSC). Black-Right-Pointing-Pointer The adipogenic impact depends strongly on the window of exposure. Black-Right-Pointing-Pointer Bisphenol A reduces the potential of MSC to differentiate into adipocytes. Black-Right-Pointing-Pointer DEHP and TBT trigger the adipogenic differentiation of mesenchymal stem cells. Black-Right-Pointing-Pointer BPA, DEHP and TBT did not affect adipogenesis in embryonic stem cells. -- Abstract: Endocrine disrupting chemicals (EDC) like bisphenol A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and tributyltin (TBT) are ubiquitously present in the environment and in human tissues. They bind to nuclear hormone receptors and affect cellular and developmental processes. In this study, we show that BPA, DEHP and TBT affect the adipogenic differentiation of murine mesenchymal stem cells (MSC, C3H/10T1/2) in a concentration-, stage- and compound-specific manner. C3H/10T1/2 cells and embryonic stem cells (CGR8) were exposed to BPA, DEHP or TBT at different stages of cell determination and differentiation (undifferentiated growth, adipogenic induction and terminal adipogenic differentiation). The final amount of differentiated adipocytes, cellular triglyceride content and mRNA expression of adipogenic marker genes (adiponectin, FABP4, PPAR{gamma}2, LPL) were quantified and compared with corresponding unexposed cells. BPA (10 {mu}M) decreased subsequent adipogenic differentiation of MSC, when cells were exposed during undifferentiated growth. In contrast, DEHP (100 {mu}M) during the hormonal induction period, and TBT (100 nM) in all investigated stages, enhanced adipogenesis. Importantly, exposure of undifferentiated murine embryonic stem cells did not show any effect of the investigated EDC on subsequent adipogenic differentiation.

  6. The Effects of High Glucose on Adipogenic and Osteogenic Differentiation of Gestational Tissue-Derived MSCs

    Directory of Open Access Journals (Sweden)

    Weerawan Hankamolsiri

    2016-01-01

    Full Text Available Most type 2 diabetic patients are obese who have increased number of visceral adipocytes. Those visceral adipocytes release several factors that enhance insulin resistance making diabetic treatment ineffective. It is known that significant percentages of visceral adipocytes are derived from mesenchymal stem cells and high glucose enhances adipogenic differentiation of mouse bone marrow-derived MSCs (BM-MSCs. However, the effect of high glucose on adipogenic differentiation of human bone marrow and gestational tissue-derived MSCs is still poorly characterized. This study aims to investigate the effects of high glucose on proliferation as well as adipogenic and osteogenic differentiation of human MSCs derived from bone marrow and several gestational tissues including chorion, placenta, and umbilical cord. We found that high glucose reduced proliferation but enhanced adipogenic differentiation of all MSCs examined. The expression levels of some adipogenic genes were also upregulated when MSCs were cultured in high glucose. Although high glucose transiently downregulated the expression levels of some osteogenic genes examined, its effect on the osteogenic differentiation levels of the MSCs is not clearly demonstrated. The knowledge gained from this study will increase our understanding about the effect of high glucose on adipogenic differentiation of MSCs and might lead to an improvement in the diabetic treatment in the future.

  7. Structure of a putative acetyltransferase (PA1377) from Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    The crystal structure of an acetyltransferase encoded by the gene PA1377 from Pseudomonas aeruginosa has been determined at 2.25 Å resolution. Comparison with a related acetyltransferase revealed a structural difference in the active site that was taken to reflect a difference in substrate binding and/or specificity between the two enzymes. Gene PA1377 from Pseudomonas aeruginosa encodes a 177-amino-acid conserved hypothetical protein of unknown function. The structure of this protein (termed pitax) has been solved in space group I222 to 2.25 Å resolution. Pitax belongs to the GCN5-related N-acetyltransferase family and contains all four sequence motifs conserved among family members. The β-strand structure in one of these motifs (motif A) is disrupted, which is believed to affect binding of the substrate that accepts the acetyl group from acetyl-CoA

  8. ARN: analysis and prediction by adipogenic professional database.

    Science.gov (United States)

    Huang, Yan; Wang, Li; Zan, And Lin-Sen

    2016-01-01

    Adipogenesis is the process of cell differentiation by which mesenchymal stem cells become adipocytes. Extensive research is ongoing to identify genes, their protein products, and microRNAs that correlate with fat cell development. The existing databases have focused on certain types of regulatory factors and interactions. However, there is no relationship between the results of the experimental studies on adipogenesis and these databases because of the lack of an information center. This information fragmentation hampers the identification of key regulatory genes and pathways. Thus, it is necessary to provide an information center that is quickly and easily accessible to researchers in this field. We selected and integrated data from eight external databases based on the results of text-mining, and constructed a publicly available database and web interface (URL: http://210.27.80.93/arn/ ), which contained 30873 records related to adipogenic differentiation. Then, we designed an online analysis tool to analyze the experimental data or form a scientific hypothesis about adipogenesis through Swanson's literature-based discovery process. Furthermore, we calculated the "Impact Factor" ("IF") value that reflects the importance of each node by counting the numbers of relation records, expression records, and prediction records for each node. This platform can support ongoing adipogenesis research and contribute to the discovery of key regulatory genes and pathways. PMID:27503118

  9. Chromium propionate enhances adipogenic differentiation of bovine intramuscular adipocytes

    Directory of Open Access Journals (Sweden)

    Rebecca eTokach

    2015-09-01

    Full Text Available In vitro experiments were performed to determine the effects of increasing concentrations of chromium propionate on mRNA and protein abundance of different enzymes and receptors. Intramuscular and subcutaneous preadipocytes and bovine satellite cells were isolated from the longissimus muscle to determine the effect of treatment on glucose transporter type 4 (GLUT4 and peroxisome proliferator-activated receptor γ mRNA and GLUT4 protein abundance. Preadipocyte cultures were treated with differentiation media plus either sodium propionate or different concentrations of chromium propionate (CrPro for 96, 120, and 144 h before harvest. This study indicated adipogenesis of the bovine intramuscular adipocytes were more sensitive to the treatment of chromium propionate as compared to subcutaneous adipocytes. Enhancement of adenosine monophosphate-activated protein kinase and GLUT4 mRNA by CrPro treatment may enhance glucose uptake in intramuscular adipocytes. Chromium propionate decreased GLUT4 protein levels in muscle cell cultures suggesting those cells have increased efficiency of glucose uptake due to exposure to increased levels of CrPro. In contrast, each of the two adipogenic lines had opposing responses to the CrPro. It appeared that CrPro had the most stimulative effect of GLUT4 response in the intramuscular adipocytes as compared to subcutaneous adipocytes. These findings indicated opportunities to potentially augment marbling in beef cattle fed chromium propionate during the finishing phase.

  10. Long-Term Fructose Intake Increases Adipogenic Potential: Evidence of Direct Effects of Fructose on Adipocyte Precursor Cells

    OpenAIRE

    Zubiría, María Guillermina; Alzamendi, Ana; Moreno, Griselda; Rey, María Amanda; Spinedi, Eduardo; Giovambattista, Andrés

    2016-01-01

    We have previously addressed that fructose rich diet (FRD) intake for three weeks increases the adipogenic potential of stromal vascular fraction cells from the retroperitoneal adipose tissue (RPAT). We have now evaluated the effect of prolonged FRD intake (eight weeks) on metabolic parameters, number of adipocyte precursor cells (APCs) and in vitro adipogenic potential from control (CTR) and FRD adult male rats. Additionally, we have examined the direct fructose effects on the adipogenic cap...

  11. Differential gene expression profiling of human bone marrow-derived mesenchymal stem cells during adipogenic development

    Directory of Open Access Journals (Sweden)

    Menssen Adriane

    2011-09-01

    Full Text Available Abstract Background Adipogenesis is the developmental process by which mesenchymal stem cells (MSC differentiate into pre-adipocytes and adipocytes. The aim of the study was to analyze the developmental strategies of human bone marrow MSC developing into adipocytes over a defined time scale. Here we were particularly interested in differentially expressed transcription factors and biochemical pathways. We studied genome-wide gene expression profiling of human MSC based on an adipogenic differentiation experiment with five different time points (day 0, 1, 3, 7 and 17, which was designed and performed in reference to human fat tissue. For data processing and selection of adipogenic candidate genes, we used the online database SiPaGene for Affymetrix microarray expression data. Results The mesenchymal stem cell character of human MSC cultures was proven by cell morphology, by flow cytometry analysis and by the ability of the cells to develop into the osteo-, chondro- and adipogenic lineage. Moreover we were able to detect 184 adipogenic candidate genes (85 with increased, 99 with decreased expression that were differentially expressed during adipogenic development of MSC and/or between MSC and fat tissue in a highly significant way (p PPARG, C/EBPA and RTXA. Several of the genes could be linked to corresponding biochemical pathways like the adipocyte differentiation, adipocytokine signalling, and lipogenesis pathways. We also identified new candidate genes possibly related to adipogenesis, such as SCARA5, coding for a receptor with a putative transmembrane domain and a collagen-like domain, and MRAP, encoding an endoplasmatic reticulum protein. Conclusions Comparing differential gene expression profiles of human MSC and native fat cells or tissue allowed us to establish a comprehensive differential kinetic gene expression network of adipogenesis. Based on this, we identified known and unknown genes and biochemical pathways that may be relevant for

  12. N-acetyltransferase in human skin and keratinocytes

    NARCIS (Netherlands)

    Vogel, Tanja; Bonifas, Jutta; Wiegman, Marjon; Pas, Hendrikus; Blömeke, Brunhilde; Coenraads, Pieter Jan; Schuttelaar, Marie-Louise

    2014-01-01

    Background: N-acetyltransferase 1 (NAT1) mediated Nacetylation in human skin and keratinocytes is an important detoxification pathway for aromatic amines including the strong sensitizer para-phenylenediamine (PPD), an important component of oxidative hair dyes. Objectives: Human skin and keratinocyt

  13. Modulation of Adipogenic Conditions for Prospective Use of hADSCs in Adipose Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Bianca Galateanu

    2012-11-01

    Full Text Available Modern strategies in adipose tissue engineering (ATE take advantage of the easy harvest, abundance and differentiation potential towards mesenchymal lineages of hADSCs. The controlled conversion of hADSCs to committed adipogenic precursors and further mature adipocytes formation is important for good long-term results in soft tissue regeneration. Thus, in this study, we report: (i the isolation of the processed lipoaspirate (PLA cells from adipose tissue and sanguine fractions; (ii the phenotypic characterization of the PLA descendants; (iii the design of a novel protocol for the modulation of adipogenic conditions in the perspectives of ATE applications. To modulate the differentiation rate through our protocol, we propose to selectively modify the formulation of the adipogenic media in accordance with the evolution of the process. Therefore, we aimed to ensure the long-term proliferation of the precursor cells and to delay the late adipogenic events. The status of differentiation was characterized in terms of intracellular lipid accumulation and reorganization of the cytoskeleton simultaneously with perilipin protein expression. Moreover, we studied the sequential activation of PPARγ2, FAS, aP2 and perilipin genes which influence the kinetics of the adipogenic process. The strategies developed in this work are the prerequisites for prospective 3D regenerative systems.

  14. Molecular Regulation of Adipogenesis and Potential Anti-Adipogenic Bioactive Molecules

    Directory of Open Access Journals (Sweden)

    Dorothy Moseti

    2016-01-01

    Full Text Available Adipogenesis is the process by which precursor stem cells differentiate into lipid laden adipocytes. Adipogenesis is regulated by a complex and highly orchestrated gene expression program. In mammalian cells, the peroxisome proliferator-activated receptor γ (PPARγ, and the CCAAT/enhancer binding proteins (C/EBPs such as C/EBPα, β and δ are considered the key early regulators of adipogenesis, while fatty acid binding protein 4 (FABP4, adiponectin, and fatty acid synthase (FAS are responsible for the formation of mature adipocytes. Excess accumulation of lipids in the adipose tissue leads to obesity, which is associated with cardiovascular diseases, type II diabetes and other pathologies. Thus, investigating adipose tissue development and the underlying molecular mechanisms is vital to develop therapeutic agents capable of curbing the increasing incidence of obesity and related pathologies. In this review, we address the process of adipogenic differentiation, key transcription factors and proteins involved, adipogenic regulators and potential anti-adipogenic bioactive molecules.

  15. [Adipogenic function and other biologic effects of insulin].

    Science.gov (United States)

    Pankov, Y A

    2016-01-01

    adipocytes during inhibition of glucose transformation into triglyceride in adipose tissue. Knockout of the Insr gene in muscles blocked glucose uptake by myocytes, but it did not induce hyperglycemia, probably due to the increase in glucose uptake by other organs, which retained the insulin receptor, and induced some increase in fat resources in adipose tissue. Similar results were obtained in mice with knockout the glucose transporter 4 GLUT4 in muscle and/or adipose tissue. Insulin microinjections in the brain, in the cerebral ventricle 4 (ICV) and mediobasal hypothalamus (MBH) did not affect the insulin levels in the general circulation, but effectively activated lipogenesis and inhibited lipolysis in adipose tissue. They induced obesity, similar to conventional obesity when the insulin levels increased. These results may serve as additional evidence for importance of the adipogenic insulin function in mechanisms of regulation of general metabolism.

  16. Evolution of arylalkylamine N-acetyltransferase: Emergence and divergence

    OpenAIRE

    Coon, Steven L.; Klein, David C.

    2006-01-01

    The melatonin rhythm-generating enzyme, arylalkylamine N-acetyltransferase (AANAT) is known to have recognizable ancient homologs in bacteria and fungi, but not in other eukaryotes. Analysis of new cDNA and genomic sequences has identified several additional homologs in other groupings. First, an AANAT homolog has been found in the genome of the cephalochordate amphioxus, representing the oldest homolog in chordates. Second, two AANAT homologs have been identified in unicellular green algae. ...

  17. Structure of Patt1 human proapoptotic histone acetyltransferase

    OpenAIRE

    Jędrzejewski, Roch Paweł; Kaźmierkiewicz, Rajmund

    2013-01-01

    The results of modeling of a novel human histone acetyltransferase Patt1 are presented here. This protein belongs to the GNAT GCN5 family and shows proapoptotic activity in human hepatocellular carcinoma cells. Patt1 is an attractive therapeutic target. The sequence analysis, fold recognition predictions and homology modeling of Patt1 protein structure were performed. N- and C- termini of Patt1 were unstructured. Central part revealed classical GNAT fold–central 7-stranded beta sheet core sur...

  18. MYST Family Histone Acetyltransferases in the Protozoan Parasite Toxoplasma gondii

    OpenAIRE

    Smith, Aaron T.; Tucker-Samaras, Samantha D.; Fairlamb, Alan H; Sullivan, William J.

    2005-01-01

    The restructuring of chromatin precedes tightly regulated events such as DNA transcription, replication, and repair. One type of chromatin remodeling involves the covalent modification of nucleosomes by histone acetyltransferase (HAT) complexes. The observation that apicidin exerts antiprotozoal activity by targeting a histone deacetyltransferase has prompted our search for more components of the histone modifying machinery in parasitic protozoa. We have previously identified GNAT family HATs...

  19. Effects of substrate stiffness on adipogenic and osteogenic differentiation of human mesenchymal stem cells.

    Science.gov (United States)

    Zhao, Wen; Li, Xiaowei; Liu, Xiaoyan; Zhang, Ning; Wen, Xuejun

    2014-07-01

    Substrate mechanical properties, in addition to biochemical signals, have been shown to modulate cell phenotype. In this study, we inspected the effects of substrate stiffness on human mesenchymal stem cells (hMSCs) derived from adult human bone marrow differentiation into adipogenic and osteogenic cells. A chemically modified extracellular matrix derived and highly biocompatible hydrogel, based on thiol functionalized hyaluronic acid (HA-SH) and thiol functionalized recombinant human gelatin (Gtn-SH), which can be crosslinked by poly (ethylene glycol) tetra-acrylate (PEGTA), was used as a model system. The stiffness of the hydrogel was controlled by adjusting the crosslinking density. Human bone marrow MSCs were cultured on the hydrogels with different stiffness under adipogenic and osteogenic conditions. Oil Red O staining and F-actin staining were applied to assess the change of cell morphologies under adipogenic and osteogenic differentiation, respectively. Gene expression of cells was determined with reverse transcription polymerase chain reaction (RT-PCR) as a function of hydrogel stiffness. Results support the hypothesis that adipogenic and osteogenic differentiation of hMSCs are inclined to occur on substrate with stiffness similar to their in vivo microenvironments. PMID:24857499

  20. Adipogenic Effects of a Combination of the Endocrine-Disrupting Compounds Bisphenol A, Diethylhexylphthalate, and Tributyltin

    Directory of Open Access Journals (Sweden)

    Ronald Biemann

    2014-01-01

    Full Text Available Objective: The food contaminants bisphenol A (BPA, diethylhexylphthalate (DEHP, and tributyltin (TBT are potent endocrine-disrupting compounds (EDC known to interfere with adipogenesis. EDC usually act in mixtures and not as single compounds. The aim of this study was to investigate the effects of a simultaneous exposure of BPA, DEHP, and TBT on mesenchymal stem cell differentiation into adipocytes. Methods: Multipotent murine mesenchymal stem cells (C3H10T1/2 were exposed to EDC mixtures in high concentrations, i.e. MIX-high (10 µmol/l BPA, 100 µmol/l DEHP, 100 nmol/l TBT, and in environmentally relevant concentrations, i.e. MIX-low (10 nmol/l BPA, 100 nmol/l DEHP, 1 nmol/l TBT. The exposure was performed either for the entire culture time (0-12 days or at distinct stages of adipogenic differentiation. At day 12 of cell culture, the amount of adipocytes, triglyceride content (TG, and adipogenic marker gene expression were analyzed. Results: MIX-high increased the development of adipocytes and the expression of adipogenic marker genes independently of the exposure window. The total TG amount was not increased. The low-concentrated EDC mixture had no obvious impact on adipogenesis. Conclusion: In EDC mixtures, the adipogenic effect of TBT and DEHP predominates single effects of BPA. Mixture effects of EDC are not deducible from single compound experiments.

  1. Subunit Composition and Substrate Specificity of a MOF-containing Histone Acetyltransferase Distinct from the Male-specific Lethal (MSL) Complex*

    Science.gov (United States)

    Cai, Yong; Jin, Jingji; Swanson, Selene K.; Cole, Michael D.; Choi, Seung Hyuk; Florens, Laurence; Washburn, Michael P.; Conaway, Joan W.; Conaway, Ronald C.

    2010-01-01

    Human MOF (MYST1), a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60) family of histone acetyltransferases (HATs), is the human ortholog of the Drosophila males absent on the first (MOF) protein. MOF is the catalytic subunit of the male-specific lethal (MSL) HAT complex, which plays a key role in dosage compensation in the fly and is responsible for a large fraction of histone H4 lysine 16 (H4K16) acetylation in vivo. MOF was recently reported to be a component of a second HAT complex, designated the non-specific lethal (NSL) complex (Mendjan, S., Taipale, M., Kind, J., Holz, H., Gebhardt, P., Schelder, M., Vermeulen, M., Buscaino, A., Duncan, K., Mueller, J., Wilm, M., Stunnenberg, H. G., Saumweber, H., and Akhtar, A. (2006) Mol. Cell 21, 811–823). Here we report an analysis of the subunit composition and substrate specificity of the NSL complex. Proteomic analyses of complexes purified through multiple candidate subunits reveal that NSL is composed of nine subunits. Two of its subunits, WD repeat domain 5 (WDR5) and host cell factor 1 (HCF1), are shared with members of the MLL/SET family of histone H3 lysine 4 (H3K4) methyltransferase complexes, and a third subunit, MCRS1, is shared with the human INO80 chromatin-remodeling complex. In addition, we show that assembly of the MOF HAT into MSL or NSL complexes controls its substrate specificity. Although MSL-associated MOF acetylates nucleosomal histone H4 almost exclusively on lysine 16, NSL-associated MOF exhibits a relaxed specificity and also acetylates nucleosomal histone H4 on lysines 5 and 8. PMID:20018852

  2. Maternal Obesity Induces Epigenetic Modifications to Facilitate Zfp423 Expression and Enhance Adipogenic Differentiation in Fetal Mice

    Science.gov (United States)

    Yang, Qi-Yuan; Liang, Jun-Fang; Rogers, Carl J.; Zhao, Jun-Xing; Zhu, Mei-Jun; Du, Min

    2013-01-01

    Maternal obesity (MO) predisposes offspring to obesity and type 2 diabetes despite poorly defined mechanisms. Zfp423 is the key transcription factor committing cells to the adipogenic lineage, with exceptionally dense CpG sites in its promoter. We hypothesized that MO enhances adipogenic differentiation during fetal development through inducing epigenetic changes in the Zfp423 promoter and elevating its expression. Female mice were subjected to a control (Con) or obesogenic (OB) diet for 2 months, mated, and maintained on their diets during pregnancy. Fetal tissue was harvested at embryonic day 14.5 (E14.5), when the early adipogenic commitment is initiated. The Zfp423 expression was 3.6-fold higher and DNA methylation in the Zfp423 promoter was lower in OB compared with Con. Correspondingly, repressive histone methylation (H3K27me3) was lower in the Zfp423 promoter of OB fetal tissue, accompanied by reduced binding of enhancer of zeste 2 (EZH2). Gain- and loss-of-function analysis showed that Zfp423 regulates early adipogenic differentiation in fetal progenitor cells. In summary, MO enhanced Zfp423 expression and adipogenic differentiation during fetal development, at least partially through reducing DNA methylation in the Zfp423 promoter, which is expected to durably elevate adipogenic differentiation of progenitor cells in adult tissue, programming adiposity and metabolic dysfunction later in life. PMID:23884886

  3. Enhanced Adipogenicity of Bone Marrow Mesenchymal Stem Cells in Aplastic Anemia

    Directory of Open Access Journals (Sweden)

    Naresh Kumar Tripathy

    2014-01-01

    Full Text Available Fatty bone marrow (BM and defective hematopoiesis are a pathologic hallmark of aplastic anemia (AA. We have investigated adipogenic and osteogenic potential of BM mesenchymal stem cells (BM-MSC in 10 AA patients (08 males and 02 females with median age of 37 years (range: 06 to 79 years and in the same number of age and sex matched controls. It was observed that BM-MSC of AA patients had a morphology, phenotype, and osteogenic differentiation potential similar to control subjects but adipocytes differentiated from AA BM-MSC had a higher density and larger size of lipid droplets and they expressed significantly higher levels of adiponectin and FABP4 genes and proteins as compared to control BM-MSC (P<0.01 for both. Thus our data shows that AA BM-MSC have enhanced adipogenicity, which may have an important implication in the pathogenesis of the disease.

  4. Exploring the activated adipogenic niche: interactions of macrophages and adipocyte progenitors.

    Science.gov (United States)

    Lee, Yun-Hee; Thacker, Robert I; Hall, Brian Eric; Kong, Raymond; Granneman, James G

    2014-01-01

    Adult adipose tissue contains a large supply of progenitors that can renew fat cells for homeostatic tissue maintenance and adaptive growth or regeneration in response to external challenges. However, the in vivo mechanisms that control adipocyte progenitor behavior are poorly characterized. We recently demonstrated that recruitment of adipocyte progenitors by macrophages is a central feature of adipose tissue remodeling under various adipogenic conditions. Catabolic remodeling of white adipose tissue by β3-adrenergic receptor stimulation requires anti-inflammatory M2-polarized macrophages to clear dying adipocytes and to recruit new brown adipocytes from progenitors. In this Extra Views article, we discuss in greater detail the cellular elements of adipogenic niches and report a strategy to isolate and characterize the subpopulations of macrophages and adipocyte progenitors that actively participate in adrenergic tissue remodeling. Further characterization of these subpopulations may facilitate identification of new cellular targets to improve metabolic and immune function of adipose tissue.

  5. Effects of hTERT immortalization on osteogenic and adipogenic differentiation of dental pulp stem cells

    Directory of Open Access Journals (Sweden)

    Ikbale El-Ayachi

    2016-03-01

    Full Text Available These data relate to the differentiation of human dental pulp stem cells (DPSC and DPSC immortalized by constitutively expressing human telomerase reverse transcriptase (hTERT through both osteogenic and adipogenic lineages (i.e. to make bone producing and fat producing cells from these dental pulp stem cells. The data augment another study to characterize immortalized DPSC for the study of neurogenetic “Characterization of neurons from immortalized dental pulp stem cells for the study of neurogenetic disorders” [1]. Two copies of one typical control cell line (technical replicates were used in this study. The data represent the differentiation of primary DPSC into osteoblast cells approximately 60% more effectively than hTERT immortalized DPSC. Conversely, both primary and immortalized DPSC are poorly differentiated into adipocytes. The mRNA expression levels for both early and late adipogenic and osteogenic gene markers are shown.

  6. Molecular mechanism underlying promiscuous polyamine recognition by spermidine acetyltransferase.

    Science.gov (United States)

    Sugiyama, Shigeru; Ishikawa, Sae; Tomitori, Hideyuki; Niiyama, Mayumi; Hirose, Mika; Miyazaki, Yuma; Higashi, Kyohei; Murata, Michio; Adachi, Hiroaki; Takano, Kazufumi; Murakami, Satoshi; Inoue, Tsuyoshi; Mori, Yusuke; Kashiwagi, Keiko; Igarashi, Kazuei; Matsumura, Hiroyoshi

    2016-07-01

    Spermidine acetyltransferase (SAT) from Escherichia coli, which catalyses the transfer of acetyl groups from acetyl-CoA to spermidine, is a key enzyme in controlling polyamine levels in prokaryotic cells. In this study, we determined the crystal structure of SAT in complex with spermidine (SPD) and CoA at 2.5Å resolution. SAT is a dodecamer organized as a hexamer of dimers. The secondary structural element and folding topology of the SAT dimer resemble those of spermidine/spermine N(1)-acetyltransferase (SSAT), suggesting an evolutionary link between SAT and SSAT. However, the polyamine specificity of SAT is distinct from that of SSAT and is promiscuous. The SPD molecule is also located at the inter-dimer interface. The distance between SPD and CoA molecules is 13Å. A deep, highly acidic, water-filled cavity encompasses the SPD and CoA binding sites. Structure-based mutagenesis and in-vitro assays identified SPD-bound residues, and the acidic residues lining the walls of the cavity are mostly essential for enzymatic activities. Based on mutagenesis and structural data, we propose an acetylation mechanism underlying promiscuous polyamine recognition for SAT. PMID:27163532

  7. Epigallocatechin Gallate Inhibits Mouse Mesenchymal Stem Cell Differentiation to Adipogenic Lineage.

    Science.gov (United States)

    Chani, Baldeep; Puri, Veena; Chander Sobti, Ranbir; Puri, Sanjeev

    2016-01-01

    Epigallocatechin gallate (EGCG) is a major component of green tea polyphenols having a potent anti-oxidant potential. Besides inhibiting the growth of many cancer cell types and inducing proliferation and differentiation in keratinocytes, it has been shown to promote reduction of body fat. The fact that mesenchymal stem cells (MSCs) have ability to self-renew and differentiate into the cells of mesodermal lineages, such as fat and bone, it is, thus, possible that EGCG may directly be involved in affecting fat metabolism through its effect on mesenchymal stem cells. Hence, with this aim, the present study was designed to determine the effect of EGCG on mouse mesenchymal stem cells, C3H10T1/2 cells differentiation into adipocytes. To understand this process, the cells were incubated with varying concentrations of EGCG (1 μM, 5 μM, 10 μM, 50 μM) in the presence and /or absence of adipogenic medium for 9 days. The results demonstrated that, EGCG inhibited the cells proliferation, migration and also prevented their differentiation to adipogenic lineage. These effects were analyzed through the inhibition of wound healing activity, reduction in Oil red O stained cells, together with decrease in the expression of Adipisin gene following EGCG treatment. These observations thus demonstrated anti-adipogenic effect of EGCG with a possibility of its role in the therapeutic intervention of obesity. PMID:27397998

  8. Anti-adipogenic effect of Artemisia annua in diet-induced-obesity mice model.

    Science.gov (United States)

    Baek, Hye Kyung; Shim, Hyeji; Lim, Hyunmook; Shim, Minju; Kim, Chul-Kyu; Park, Sang-Kyu; Lee, Yong Seok; Song, Ki-Duk; Kim, Sung-Jo; Yi, Sun Shin

    2015-01-01

    Obesity has increased continuously in western countries during the last several decades and recently become a problem in developing countries. Currently, anti-obesity drugs originating from natural products are being investigated for their potential to overcome adverse effects associated with chemical drugs. Artemisinic acid, which was isolated from the well-known anti-malaria herb Artemisia annua (AA) L., was recently shown to possess anti-adipogenic effects in vitro. However, the anti-adipogenic effects of AA in animal models have not yet been investigated. Therefore, we conducted daily oral administration with AA water extract in a diet-induced obesity animal model and treated 3T3-L1 cells with AA to confirm the anti-adipogenic effects in the related protein expressions. We then evaluated the physiology, adipose tissue histology and mRNA expressions of many related genes. Inhibition of adipogenesis by the AA water extract was observed in vitro. In the animal model, weight gain was significantly lower in the AA treated group, but there were no changes in food intake volume or calories. Reductions in lipid droplet size and mRNA expression associated with adipogenesis were also observed in animal epididymal fat. This study is the first to report that AA has an anti-obese effects in vivo. PMID:26243598

  9. Adipogenic differentiation state-specific gene expression as related to bovine carcass adiposity.

    Science.gov (United States)

    Pickworth, C L; Loerch, S C; Velleman, S G; Pate, J L; Poole, D H; Fluharty, F L

    2011-02-01

    Genetic regulation of the site of fat deposition is not well defined. The objective of this study was to investigate adipogenic differentiation state-specific gene expression in feedlot cattle (>75% Angus; Simmental parentage) of varying adipose accretion patterns. Four groups of 4 steers were selected via ultrasound for the following adipose tissue characteristics: low subcutaneous-low intramuscular (LSQ-LIM), low subcutaneous-high intramuscular (LSQ-HIM), high subcutaneous-low intramuscular (HSQ-LIM), and high subcutaneous-high intramuscular (HSQ-HIM). Adipose tissue from the subcutaneous (SQ) and intramuscular (IM) depots was collected at slaughter. The relative expression of adipogenic genes was evaluated using quantitative PCR. Data were analyzed using the mixed model of SAS, and gene expression data were analyzed using covariate analysis with ribosomal protein L19 as the covariate. No interactions (P > 0.10) were observed between IM and SQ adipose tissue depots for any of the variables measured. Therefore, only the main effects of high and low accretion within a depot and the effects of depot are reported. Steers with LIM had smaller mean diameter IM adipocytes (P 0.10) in any of the genes measured due to high or low adipose accretion. Preadipogenic delta-like kinase1 mRNA was greater in the IM than the SQ adipose tissue; conversely, differentiating and adipogenic genes, lipoprotein lipase, PPARγ, fatty acid synthetase, and fatty acid binding protein 4 were greater (P < 0.001) in the SQ than the IM depot. Intramuscular adipocytes were smaller than SQ adipocytes and had greater expression of the preadipogenic gene, indicating that more hyperplasia was occurring. Meanwhile, SQ adipose tissue contained much larger (P < 0.001) adipocytes that had a greater expression (P < 0.001) of differentiating and adipogenic genes than did the IM adipose tissue, indicating more cells were undergoing differentiation and hypertrophy. Adipogenic differentiation state

  10. Reduction of choline acetyltransferase activities in APP770 transgenic mice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Transgenic mice overexpressing the 770-amino acid isoform of human Alzheimer amyloid precursor protein exhibit extracellular b -amyloid deposits in brain regions including cerebral cortex and hippocampus, which are severely affected in Alzheimer's disease patients. Significant reduction in choline acetyltransferase (ChAT) activities has been observed in both cortical and hippocampal brain regions in the transgenic mice at the age of 10 months compared with the age-matched non-transgenic mice, but such changes have not been observed in any brain regions of the transgenic mice under the age of 5 months. These results suggest that deposition of b -amyloid can induce changes in the brain cholinergic system of the transgenic mice.

  11. Long-Term Fructose Intake Increases Adipogenic Potential: Evidence of Direct Effects of Fructose on Adipocyte Precursor Cells.

    Science.gov (United States)

    Zubiría, María Guillermina; Alzamendi, Ana; Moreno, Griselda; Rey, María Amanda; Spinedi, Eduardo; Giovambattista, Andrés

    2016-01-01

    We have previously addressed that fructose rich diet (FRD) intake for three weeks increases the adipogenic potential of stromal vascular fraction cells from the retroperitoneal adipose tissue (RPAT). We have now evaluated the effect of prolonged FRD intake (eight weeks) on metabolic parameters, number of adipocyte precursor cells (APCs) and in vitro adipogenic potential from control (CTR) and FRD adult male rats. Additionally, we have examined the direct fructose effects on the adipogenic capacity of normal APCs. FRD fed rats had increased plasma levels of insulin, triglyceride and leptin, and RPAT mass and adipocyte size. FACS studies showed higher APCs number and adipogenic potential in FRD RPAT pads; data is supported by high mRNA levels of competency markers: PPARγ2 and Zfp423. Complementary in vitro experiments indicate that fructose-exposed normal APCs displayed an overall increased adipogenic capacity. We conclude that the RPAT mass expansion observed in eight week-FRD fed rats depends on combined accelerated adipogenesis and adipocyte hypertrophy, partially due to a direct effect of fructose on APCs. PMID:27049396

  12. Long-Term Fructose Intake Increases Adipogenic Potential: Evidence of Direct Effects of Fructose on Adipocyte Precursor Cells

    Directory of Open Access Journals (Sweden)

    María Guillermina Zubiría

    2016-04-01

    Full Text Available We have previously addressed that fructose rich diet (FRD intake for three weeks increases the adipogenic potential of stromal vascular fraction cells from the retroperitoneal adipose tissue (RPAT. We have now evaluated the effect of prolonged FRD intake (eight weeks on metabolic parameters, number of adipocyte precursor cells (APCs and in vitro adipogenic potential from control (CTR and FRD adult male rats. Additionally, we have examined the direct fructose effects on the adipogenic capacity of normal APCs. FRD fed rats had increased plasma levels of insulin, triglyceride and leptin, and RPAT mass and adipocyte size. FACS studies showed higher APCs number and adipogenic potential in FRD RPAT pads; data is supported by high mRNA levels of competency markers: PPARγ2 and Zfp423. Complementary in vitro experiments indicate that fructose-exposed normal APCs displayed an overall increased adipogenic capacity. We conclude that the RPAT mass expansion observed in eight week-FRD fed rats depends on combined accelerated adipogenesis and adipocyte hypertrophy, partially due to a direct effect of fructose on APCs.

  13. Small molecule inhibitors of histone deacetylases and acetyltransferases as potential therapeutics in oncology

    NARCIS (Netherlands)

    van den Bosch, Teatske; Leus, Niek; Timmerman, Tirza; Dekker, Frans

    2016-01-01

    Uncontrolled cell proliferation and resistance to apoptosis in cancer are, among others, regulated by post-translational modifications of histone proteins. The most investigated type of histone modification is lysine acetylation. Histone acetyltransferases (HATs), acetylate histone lysine residues,

  14. 18{beta}-Glycyrrhetinic acid inhibits adipogenic differentiation and stimulates lipolysis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Myung-Hee; Jeong, Jae-Kyo; Lee, You-Jin; Seol, Jae-Won; Ahn, Dong-Choon; Kim, In-Shik [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Park, Sang-Youel, E-mail: sypark@chonbuk.ac.kr [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer 18{beta}-GA inhibits adipogenic differentiation in 3T3-L1 preadipocytes and stimulates lipolysis in differentiated adipocytes. Black-Right-Pointing-Pointer Anti-adipogenic effect of 18{beta}-GA is caused by down-regulation of PPAR{gamma} and inactivation of Akt signalling. Black-Right-Pointing-Pointer Lipolytic effect of 18{beta}-GA is mediated by up-regulation of HSL, ATGL and perilipin and activation of HSL. -- Abstract: 18{beta}-Glycyrrhetinic acid (18{beta}-GA) obtained from the herb liquorice has various pharmacological properties including anti-inflammatory and anti-bacterial activities. However, potential biological anti-obesity activities are unclear. In this study, novel biological activities of 18{beta}-GA in the adipogenesis of 3T3-L1 preadipocytes and in lipolysis of differentiated adipocytes were identified. Mouse 3T3-L1 cells were used as an in vitro model of adipogenesis and lipolysis, using a mixture of insulin/dexamethasone/3-isobutyl-1-methylxanthine (IBMX) to induce differentiation. The amount of lipid droplet accumulation was determined by an AdipoRed assay. The expression of several adipogenic transcription factors and enzymes was investigated using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. 18{beta}-GA dose-dependently (1-40 {mu}M) significantly decreased lipid accumulation in maturing preadipocytes. In 3T3-L1 preadipocytes, 10 {mu}M of 18{beta}-GA down-regulated the transcriptional levels of the peroxisome proliferator-activated receptor {gamma}, CCAAT/enhancer-binding protein {alpha} and adiponectin, which are markers of adipogenic differentiation via Akt phosphorylation. Also, in differentiated adipocytes, 18{beta}-GA increased the level of glycerol release and up-regulated the mRNA of hormone-sensitive lipase, adipose TG lipase and perilipin, as well as the phosphorylation of hormone-sensitive lipase at Serine 563. The results indicate that 18{beta

  15. Enhanced Adipogenicity of Bone Marrow Mesenchymal Stem Cells in Aplastic Anemia

    OpenAIRE

    Naresh Kumar Tripathy; Saurabh Pratap Singh; Soniya Nityanand

    2014-01-01

    Fatty bone marrow (BM) and defective hematopoiesis are a pathologic hallmark of aplastic anemia (AA). We have investigated adipogenic and osteogenic potential of BM mesenchymal stem cells (BM-MSC) in 10 AA patients (08 males and 02 females) with median age of 37 years (range: 06 to 79 years) and in the same number of age and sex matched controls. It was observed that BM-MSC of AA patients had a morphology, phenotype, and osteogenic differentiation potential similar to control subjects but adi...

  16. Extracellular matrix of adipogenically differentiated mesenchymal stem cells reveals a network of collagen filaments, mostly interwoven by hexagonal structural units.

    Science.gov (United States)

    Ullah, Mujib; Sittinger, Michael; Ringe, Jochen

    2013-01-01

    Extracellular matrix (ECM) is the non-cellular component of tissues, which not only provides biological shelter but also takes part in the cellular decisions for diverse functions. Every tissue has an ECM with unique composition and topology that governs the process of determination, differentiation, proliferation, migration and regeneration of cells. Little is known about the structural organization of matrix especially of MSC-derived adipogenic ECM. Here, we particularly focus on the composition and architecture of the fat ECM to understand the cellular behavior on functional bases. Thus, mesenchymal stem cells (MSC) were adipogenically differentiated, then, were transferred to adipogenic propagation medium, whereas they started the release of lipid droplets leaving bare network of ECM. Microarray analysis was performed, to indentify the molecular machinery of matrix. Adipogenesis was verified by Oil Red O staining of lipid droplets and by qPCR of adipogenic marker genes PPARG and FABP4. Antibody staining demonstrated the presence of collagen type I, II and IV filaments, while alkaline phosphatase activity verified the ossified nature of these filaments. In the adipogenic matrix, the hexagonal structures were abundant followed by octagonal structures, whereas they interwoven in a crisscross manner. Regarding molecular machinery of adipogenic ECM, the bioinformatics analysis revealed the upregulated expression of COL4A1, ITGA7, ITGA7, SDC2, ICAM3, ADAMTS9, TIMP4, GPC1, GPC4 and downregulated expression of COL14A1, ADAMTS5, TIMP2, TIMP3, BGN, LAMA3, ITGA2, ITGA4, ITGB1, ITGB8, CLDN11. Moreover, genes associated with integrins, glycoproteins, laminins, fibronectins, cadherins, selectins and linked signaling pathways were found. Knowledge of the interactive-language between cells and matrix could be beneficial for the artificial designing of biomaterials and bioscaffolds. PMID:23851162

  17. Impact of bacteria and bacterial components on osteogenic and adipogenic differentiation of adipose-derived mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Tomas, E-mail: tomas.fiedler@med.uni-rostock.de [Institute for Medical Microbiology, Virology, and Hygiene, Rostock University Medical Center, Schillingallee 70, D-18057 Rostock (Germany); Salamon, Achim; Adam, Stefanie; Herzmann, Nicole [Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany); Taubenheim, Jan [Institute for Medical Microbiology, Virology, and Hygiene, Rostock University Medical Center, Schillingallee 70, D-18057 Rostock (Germany); Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany); Peters, Kirsten [Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany)

    2013-11-01

    Adult mesenchymal stem cells (MSC) are present in several tissues, e.g. bone marrow, heart muscle, brain and subcutaneous adipose tissue. In invasive infections MSC get in contact with bacteria and bacterial components. Not much is known about how bacterial pathogens interact with MSC and how contact to bacteria influences MSC viability and differentiation potential. In this study we investigated the impact of three different wound infection relevant bacteria, Escherichia coli, Staphylococcus aureus, and Streptococcus pyogenes, and the cell wall components lipopolysaccharide (LPS; Gram-negative bacteria) and lipoteichoic acid (LTA; Gram-positive bacteria) on viability, proliferation, and osteogenic as well as adipogenic differentiation of human adipose tissue-derived mesenchymal stem cells (adMSC). We show that all three tested species were able to attach to and internalize into adMSC. The heat-inactivated Gram-negative E. coli as well as LPS were able to induce proliferation and osteogenic differentiation but reduce adipogenic differentiation of adMSC. Conspicuously, the heat-inactivated Gram-positive species showed the same effects on proliferation and adipogenic differentiation, while its cell wall component LTA exhibited no significant impact on adMSC. Therefore, our data demonstrate that osteogenic and adipogenic differentiation of adMSC is influenced in an oppositional fashion by bacterial antigens and that MSC-governed regeneration is not necessarily reduced under infectious conditions. - Highlights: • Staphylococcus aureus, Streptococcus pyogenes and Escherichia coli bind to and internalize into adMSC. • Heat-inactivated cells of these bacterial species trigger proliferation of adMSC. • Heat-inactivated E. coli and LPS induce osteogenic differentiation of adMSC. • Heat-inactivated E. coli and LPS reduce adipogenic differentiation of adMSC. • LTA does not influence adipogenic or osteogenic differentiation of adMSC.

  18. Epigenetic Regulation of Mesenchymal Stem Cells: A Focus on Osteogenic and Adipogenic Differentiation

    Directory of Open Access Journals (Sweden)

    Chad M. Teven

    2011-01-01

    Full Text Available Stem cells are characterized by their capability to self-renew and terminally differentiate into multiple cell types. Somatic or adult stem cells have a finite self-renewal capacity and are lineage-restricted. The use of adult stem cells for therapeutic purposes has been a topic of recent interest given the ethical considerations associated with embryonic stem (ES cells. Mesenchymal stem cells (MSCs are adult stem cells that can differentiate into osteogenic, adipogenic, chondrogenic, or myogenic lineages. Owing to their ease of isolation and unique characteristics, MSCs have been widely regarded as potential candidates for tissue engineering and repair. While various signaling molecules important to MSC differentiation have been identified, our complete understanding of this process is lacking. Recent investigations focused on the role of epigenetic regulation in lineage-specific differentiation of MSCs have shown that unique patterns of DNA methylation and histone modifications play an important role in the induction of MSC differentiation toward specific lineages. Nevertheless, MSC epigenetic profiles reflect a more restricted differentiation potential as compared to ES cells. Here we review the effect of epigenetic modifications on MSC multipotency and differentiation, with a focus on osteogenic and adipogenic differentiation. We also highlight clinical applications of MSC epigenetics and nuclear reprogramming.

  19. KR-62980: a novel peroxisome proliferator-activated receptor gamma agonist with weak adipogenic effects.

    Science.gov (United States)

    Kim, Kwang Rok; Lee, Jeong Hyung; Kim, Seung Jun; Rhee, Sang Dal; Jung, Won Hoon; Yang, Sung-Don; Kim, Sung Soo; Ahn, Jin Hee; Cheon, Hyae Gyeong

    2006-08-14

    The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) is the target for the anti-diabetic drugs including thiazolidinediones. We report here the identification and characterization of a novel PPARgamma agonist KR-62980. KR-62980 acted as a selective PPARgamma agonist in transactivation assay with an EC50 of 15 nM. In fully differentiated 3T3-L1 adipocytes, KR-62980 induced [3H]-deoxyglucose uptake in a concentration-dependent manner in the presence of insulin. KR-62980 was weakly adipogenic with little induction of aP2 mRNA, and was able to antagonize the adipogenic effects of rosiglitazone in C3H10T1/2 cells. In vivo pharmacokinetic profile of KR-62980 revealed that the compound exhibited good oral bioavailability of 65% with a terminal elimination half-life of 2.5 h in the rat. Treatment of high fat diet-induced C57BL/6J mice with KR-62980 for 14 days reduced plasma glucose levels with little side effects with regard to weight gain, cardiac hypertrophy and hepatotoxicity. These results suggest that KR-62980 acts as a selective PPARgamma modulator with anti-hyperglycemic activity, and that the mechanism of actions of KR-62980 appears to be different from that of rosiglitazone with improved side effect profiles.

  20. Reconstruction of N-acetyltransferase 2 haplotypes using PHASE.

    Science.gov (United States)

    Golka, Klaus; Blaszkewicz, Meinolf; Samimi, Mirabutaleb; Bolt, Hermann M; Selinski, Silvia

    2008-04-01

    The genotyping of N-acetyltransferase 2 (NAT2) by PCR/RFLP methods yields in a considerable percentage ambiguous results. To resolve this methodical problem a statistical approach was applied. PHASE v2.1.1, a statistical program for haplotype reconstruction was used to estimate haplotype pairs from NAT2 genotyping data, obtained by the analysis of seven single nucleotide polymorphisms relevant for Caucasians. In 1,011 out of 2,921 (35%) subjects the haplotype pairs were clearcut by the PCR/RFLP data only. For the majority of the data the applied method resulted in a multiplicity (2-4) of possible haplotype pairs. Haplotype reconstruction using PHASE v2.1.1 cleared this ambiguity in all cases but one, where an alternative haplotype pair was considered with a probability of 0.029. The estimation of the NAT2 haplotype is important because the assignment of the NAT2 alleles *12A, *12B, *12C or *13 to the rapid or slow NAT2 genotype has been discussed controversially. A clear assignment is indispensable in surveys of human bladder cancer caused by aromatic amine exposures. In conclusion, PHASE v2.1.1 software allowed an unambiguous haplotype reconstruction in 2,920 of 2,921 cases (>99.9%).

  1. Dysregulation of Histone Acetyltransferases and Deacetylases in Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Yonggang Wang

    2014-01-01

    Full Text Available Cardiovascular disease (CVD remains a leading cause of mortality worldwide despite advances in its prevention and management. A comprehensive understanding of factors which contribute to CVD is required in order to develop more effective treatment options. Dysregulation of epigenetic posttranscriptional modifications of histones in chromatin is thought to be associated with the pathology of many disease models, including CVD. Histone acetyltransferases (HATs and deacetylases (HDACs are regulators of histone lysine acetylation. Recent studies have implicated a fundamental role of reversible protein acetylation in the regulation of CVDs such as hypertension, pulmonary hypertension, diabetic cardiomyopathy, coronary artery disease, arrhythmia, and heart failure. This reversible acetylation is governed by enzymes that HATs add or HDACs remove acetyl groups respectively. New evidence has revealed that histone acetylation regulators blunt cardiovascular and related disease states in certain cellular processes including myocyte hypertrophy, apoptosis, fibrosis, oxidative stress, and inflammation. The accumulating evidence of the detrimental role of histone acetylation in cardiac disease combined with the cardioprotective role of histone acetylation regulators suggests that the use of histone acetylation regulators may serve as a novel approach to treating the millions of patients afflicted by cardiac diseases worldwide.

  2. Recombinant genomes which express chloramphenicol acetyltransferase in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Gorman, C.M.; Moffat, L.F.; Howard, B.H.

    1982-09-01

    The authors constructed a series of recombinant genomes which directed expression of the enzyme chloramphenicol acetyltransferase (CAT) in mammalian cells. The prototype recombinant in this series, pSV2-cat, consisted of the beta-lactamase gene and origin of replication from pBR322 coupled to a simian virus 40 (SV40) early transcription region into which CAT coding sequences were inserted. Readily measured levels of CAT accumulated within 48 h after the introduction of pSV2-cat DNA into African green monkey kidney CV-1 cells. Because endogenous CAT activity is not present in CV-1 or other mammalian cells, and because rapid, sensitive assays for CAT activity are available, these recombinants provided a uniquely convenient system for monitoring the expression of foreign DNAs in tissue culture cells. To demonstrate the usefulness of this system, we constructed derivatives of pSV2-cat from which part or all of the SV 40 promoter region was removed. Deletion of one copy of the 72-base-pair repeat sequence in the SV40 promoter caused no significant decrease in CAT synthesis in monkey kidney CV-1 cells; however, an additional deletion of 50 base pairs from the second copy of the repeats reduced CAT synthesis to 11% of its level in the wild type. They also constructed a recombinant, pSVO-cat, in which the entire SV40 promoter region was removed and a unique HindIII site was substituted for the insertion of other promoter sequences.

  3. Serum Aminoglycoside Assay by Enzyme-Mediated Immunoassay (EMIT): Correlation with Radioimmunoassay, Fluoroimmunoassay, and Acetyltransferase and Microbiological Assays

    OpenAIRE

    White, L O; Scammell, L. M.; Reeves, D S

    1981-01-01

    Enzyme-mediated immunoassay (EMIT) serum aminoglycoside assay results were accurate and precise and correlated well with radioimmunoassay, fluoroimmunoassay, and acetyltransferase and microbiological assay determinations.

  4. Anti-Adipogenic Effects of Ethanol Extracts Prepared from Selected Medicinal Herbs in 3T3-L1 Cells

    Science.gov (United States)

    Park, Min-Jun; Song, Ji-Hye; Shon, Myung-Soo; Kim, Hae Ok; Kwon, O Jun; Roh, Seong-Soo; Kim, Choon Young; Kim, Gyo-Nam

    2016-01-01

    Obesity is a major risk factor for various metabolic diseases such as cardiovascular disease, hypertension, and type 2 diabetes mellitus. In this study, we prepared ethanol extracts from Agastache rugosa (ARE), Chrysanthemum zawadskii (CZE), Mentha arvensis (MAE), Perilla frutescens (PFE), Leonurus sibiricus (LSE), Gardenia jasminoides (GJE), and Lycopus coreanus (LCE). The anti-oxidant and anti-adipogenic effects were evaluated. The IC50 values for ascorbic acid and LCE against 2,2-diphenyl-1-picrylhydrazyl radicals were 246.2 μg/mL and 166.2 μg/mL, respectively, followed by ARE (186.6 μg/mL), CZE (198.6 μg/mL), MAE (337.1 μg/mL), PFE (415.3 μg/mL), LSE (548.2 μg/mL), and GJE (626.3 μg/mL). In non-toxic concentration ranges, CZE had a strong inhibitory effect against 3T3-L1 adipogenes (84.5%) than those of the other extracts. Furthermore, the anti-adipogenic effect of CZE is largely limited in the early stage of adipogenesis, and we revealed that the inhibitory role of CZE in adipogenesis is required for the activation of Wnt signaling. Our results provide scientific evidence that the anti-adipogenic effect of CZE can be applied as an ingredient for the development of functional foods and nutri-cosmetics for obesity prevention. PMID:27752499

  5. Basic fibroblast growth factor is pro-adipogenic in rat skeletal muscle progenitor clone, 2G11 cells.

    Science.gov (United States)

    Nakano, Shin-ichi; Nakamura, Katsuyuki; Teramoto, Naomi; Yamanouchi, Keitaro; Nishihara, Masugi

    2016-01-01

    Intramuscular adipose tissue (IMAT) formation is a hallmark of marbling in cattle. IMAT is considered to originate from skeletal muscle progenitor cells with adipogenic potential. However, the mechanism involved in IMAT formation from these progenitor cells in vivo remains unclear. In the present study, among the growth factors tested, which were known to be expressed in skeletal muscle, we found only basic fibroblast growth factor (bFGF) has a pro-adipogenic effect on skeletal muscle derived adipogenic progenitor clone, 2G11 cells. Pre-exposure of 2G11 cells to bFGF did not affect initial gene expressions of CCAAT/enhancer-binding protein (C/EBP)β and C/EBPδ, while resulting in an enhancement of subsequent expressions of C/EBPα and proliferator-activated receptor gamma (PPARγ) during adipogenesis, indicating that bFGF is acting on the transcriptional regulation of C/EBPα and PPARγ. In addition, the effect of bFGF is mediated via two types of FGF receptor (FGFR) isoforms: FGFR1 and FGFR2 IIIc, and both receptors are prerequisite for bFGF to express its pro-adipogenic effect. These results suggest that bFGF plays an important role as a key trigger of IMAT formation in vivo. PMID:26154243

  6. Arsenic trioxide promotes senescence and regulates the balance of adipogenic and osteogenic differentiation in human mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Huanchen Cheng; Lin Qiu; Hao Zhang; Mei Cheng; Wei Li; Xuefei Zhao; Keyu Liu; Lei Lei; Jun Ma

    2011-01-01

    Arsenic trioxide (ATO) as an anti-tumor drug could induce differentiation and apoptosis in tumor cells.Mesenchymal stem cells (MSCs) play important roles in the hematogenesis of bone marrow. Many reports have shown that the disorder of MSC adipogenic and osteogenic differentiation occurs in some diseases. However,reports about the effects of ATO on MSCs are limited. In this study, we found that 1μM ATO promoted MSC senescence mainly through p21, although it had no effect on apoptosis at this dose. Furthermore, ATO promoted adipogenic differentiation, but inhibited osteogenic differentiation in MSCs. Our study also showed that CCAAT/enhancer-binding protein alpha C/EBPα and peroxisome proliferator-activated receptor gamma PPARγ might be involved in the regulation of adipogenic and osteogenic differentiation induced by ATO. Our results indicated that ATO may exert an anti-tumor effect by influencing bone marrow micro-environment. Moreover, it may regulate the adipogenic and osteogenic differentiation of MSCs.

  7. N-Alpha-Acetyltransferases and Regulation of CFTR Expression.

    Directory of Open Access Journals (Sweden)

    Ali J Vetter

    Full Text Available The majority of cystic fibrosis (CF-causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR lead to the misfolding, mistrafficking, and degradation of the mutant protein. Inhibition of degradation does not effectively increase the amount of trafficking competent CFTR, but typically leads to increased ER retention of misfolded forms. Thus, the initial off pathway steps occur early in the processing of the protein. To identify proteins that interact with these early forms of CFTR, in vitro crosslink experiments identified cotranslational partners of the nascent chain of the severe misfolded mutant, G85E CFTR. The mutant preferentially interacts with a subunit of an N-alpha-acetyltransferase A. Based on recent reports that acetylation of the N-termini of some N-end rule substrates control their ubiquitination and subsequent degradation, a potential role for this modification in regulation of CFTR expression was assessed. Knockdown experiments identified two complexes, which affect G85E CFTR proteins levels, NatA and NatB. Effects of the knockdowns on mRNA levels, translation rates, and degradation rates established that the two complexes regulate G85E CFTR through two separate mechanisms. NatA acts indirectly by regulating transcription levels and NatB acts through a previously identified, but incompletely understood posttranslational mechanism. This regulation did not effect trafficking of G85E CFTR, which remains retained in the ER, nor did it alter the degradation rate of CFTR. A mutation predicted to inhibit N-terminal acetylation of CFTR, Q2P, was without effect, suggesting neither system acts directly on CFTR. These results contradict the prediction that N-terminal acetylation of CFTR determines its fitness as a proteasome substrate, but rather NatB plays a role in the conformational maturation of CFTR in the ER through actions on an unidentified protein.

  8. N-Alpha-Acetyltransferases and Regulation of CFTR Expression.

    Science.gov (United States)

    Vetter, Ali J; Karamyshev, Andrey L; Patrick, Anna E; Hudson, Henry; Thomas, Philip J

    2016-01-01

    The majority of cystic fibrosis (CF)-causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) lead to the misfolding, mistrafficking, and degradation of the mutant protein. Inhibition of degradation does not effectively increase the amount of trafficking competent CFTR, but typically leads to increased ER retention of misfolded forms. Thus, the initial off pathway steps occur early in the processing of the protein. To identify proteins that interact with these early forms of CFTR, in vitro crosslink experiments identified cotranslational partners of the nascent chain of the severe misfolded mutant, G85E CFTR. The mutant preferentially interacts with a subunit of an N-alpha-acetyltransferase A. Based on recent reports that acetylation of the N-termini of some N-end rule substrates control their ubiquitination and subsequent degradation, a potential role for this modification in regulation of CFTR expression was assessed. Knockdown experiments identified two complexes, which affect G85E CFTR proteins levels, NatA and NatB. Effects of the knockdowns on mRNA levels, translation rates, and degradation rates established that the two complexes regulate G85E CFTR through two separate mechanisms. NatA acts indirectly by regulating transcription levels and NatB acts through a previously identified, but incompletely understood posttranslational mechanism. This regulation did not effect trafficking of G85E CFTR, which remains retained in the ER, nor did it alter the degradation rate of CFTR. A mutation predicted to inhibit N-terminal acetylation of CFTR, Q2P, was without effect, suggesting neither system acts directly on CFTR. These results contradict the prediction that N-terminal acetylation of CFTR determines its fitness as a proteasome substrate, but rather NatB plays a role in the conformational maturation of CFTR in the ER through actions on an unidentified protein.

  9. N-Alpha-Acetyltransferases and Regulation of CFTR Expression.

    Science.gov (United States)

    Vetter, Ali J; Karamyshev, Andrey L; Patrick, Anna E; Hudson, Henry; Thomas, Philip J

    2016-01-01

    The majority of cystic fibrosis (CF)-causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) lead to the misfolding, mistrafficking, and degradation of the mutant protein. Inhibition of degradation does not effectively increase the amount of trafficking competent CFTR, but typically leads to increased ER retention of misfolded forms. Thus, the initial off pathway steps occur early in the processing of the protein. To identify proteins that interact with these early forms of CFTR, in vitro crosslink experiments identified cotranslational partners of the nascent chain of the severe misfolded mutant, G85E CFTR. The mutant preferentially interacts with a subunit of an N-alpha-acetyltransferase A. Based on recent reports that acetylation of the N-termini of some N-end rule substrates control their ubiquitination and subsequent degradation, a potential role for this modification in regulation of CFTR expression was assessed. Knockdown experiments identified two complexes, which affect G85E CFTR proteins levels, NatA and NatB. Effects of the knockdowns on mRNA levels, translation rates, and degradation rates established that the two complexes regulate G85E CFTR through two separate mechanisms. NatA acts indirectly by regulating transcription levels and NatB acts through a previously identified, but incompletely understood posttranslational mechanism. This regulation did not effect trafficking of G85E CFTR, which remains retained in the ER, nor did it alter the degradation rate of CFTR. A mutation predicted to inhibit N-terminal acetylation of CFTR, Q2P, was without effect, suggesting neither system acts directly on CFTR. These results contradict the prediction that N-terminal acetylation of CFTR determines its fitness as a proteasome substrate, but rather NatB plays a role in the conformational maturation of CFTR in the ER through actions on an unidentified protein. PMID:27182737

  10. Structural Studies on a Glucosamine/Glucosaminide N-Acetyltransferase.

    Science.gov (United States)

    Dopkins, Brandon J; Tipton, Peter A; Thoden, James B; Holden, Hazel M

    2016-08-16

    Glucosamine/glucosaminide N-acetyltransferase or GlmA catalyzes the transfer of an acetyl group from acetyl CoA to the primary amino group of glucosamine. The enzyme from Clostridium acetobutylicum is thought to be involved in cell wall rescue. In addition to glucosamine, GlmA has been shown to function on di- and trisaccharides of glucosamine as well. Here we present a structural and kinetic analysis of the enzyme. For this investigation, eight structures were determined to resolutions of 2.0 Å or better. The overall three-dimensional fold of GlmA places it into the tandem GNAT superfamily. Each subunit of the dimer folds into two distinct domains which exhibit high three-dimensional structural similarity. Whereas both domains bind acetyl CoA, it is the C-terminal domain that is catalytically competent. On the basis of the various structures determined in this investigation, two amino acid residues were targeted for further study: Asp 287 and Tyr 297. Although their positions in the active site suggested that they may play key roles in catalysis by functioning as active site bases and acids, respectively, this was not borne out by characterization of the D287N and Y297F variants. The kinetic properties revealed that both residues were important for substrate binding but had no critical roles as acid/base catalysts. Kinetic analyses also indicated that GlmA follows an ordered mechanism with acetyl CoA binding first followed by glucosamine. The product N-acetylglucosamine is then released prior to CoA. The investigation described herein provides significantly new information on enzymes belonging to the tandem GNAT superfamily.

  11. Dose-dependent effect of estrogen suppresses the osteo-adipogenic transdifferentiation of osteoblasts via canonical Wnt signaling pathway.

    Directory of Open Access Journals (Sweden)

    Bo Gao

    Full Text Available Fat infiltration within marrow cavity is one of multitudinous features of estrogen deficiency, which leads to a decline in bone formation functionality. The origin of this fat is unclear, but one possibility is that it is derived from osteoblasts, which transdifferentiate into adipocytes that produce bone marrow fat. We examined the dose-dependent effect of 17β-estradiol on the ability of MC3T3-E1 cells and murine bone marrow-derived mesenchymal stem cell (BMMSC-derived osteoblasts to undergo osteo-adipogenic transdifferentiation. We found that 17β-estradiol significantly increased alkaline phosphatase activity (P<0.05; calcium deposition; and Alp, Col1a1, Runx2, and Ocn expression levels dose-dependently. By contrast, 17β-estradiol significantly decreased the number and size of lipid droplets, and Fabp4 and PPARγ expression levels during osteo-adipogenic transdifferentiation (P<0.05. Moreover, the expression levels of brown adipocyte markers (Myf5, Elovl3, and Cidea and undifferentiated adipocyte markers (Dlk1, Gata2, and Wnt10b were also affected by 17β-estradiol during osteo-adipogenic transdifferentiation. Western blotting and immunostaining further showed that canonical Wnt signaling can be activated by estrogen to exert its inhibitory effect of osteo-adipogenesis. This is the first study to demonstrate the dose-dependent effect of 17β-estradiol on the osteo-adipogenic transdifferentiation of MC3T3-E1 cells and BMMSCs likely via canonical Wnt signaling. In summary, our results indicate that osteo-adipogenic transdifferentiation modulated by canonical Wnt signaling pathway in bone metabolism may be a new explanation for the gradually increased bone marrow fat in estrogen-inefficient condition.

  12. The effect of cell passage number on osteogenic and adipogenic characteristics of D1 cells.

    Science.gov (United States)

    Kwist, K; Bridges, W C; Burg, K J L

    2016-08-01

    Cell line passage number is an important consideration when designing an experiment. At higher passages, it is generally understood that cell health begins to decline and, when this occurs, the result can be variable data. However, there are no specific guidelines regarding optimal passage range, and this information is dependent on cell type. To explore these variabilities, low passage D1 cells were thawed (passage 3) and passaged serially until a much higher number (passage 34). Samples were taken every five passages and analyzed for alkaline phosphatase and triglyceride; also, the gene expression of both adipogenic and osteogenic markers was tested. The results indicate that the growth rate of these cells did slow down after passage 30. However, expression of the osteogenic characteristics seemed to cycle, with the highest levels seen at passage 4 and 24. The adipocyte expression levels remained the same throughout the study. PMID:26208915

  13. The effect of cell passage number on osteogenic and adipogenic characteristics of D1 cells.

    Science.gov (United States)

    Kwist, K; Bridges, W C; Burg, K J L

    2016-08-01

    Cell line passage number is an important consideration when designing an experiment. At higher passages, it is generally understood that cell health begins to decline and, when this occurs, the result can be variable data. However, there are no specific guidelines regarding optimal passage range, and this information is dependent on cell type. To explore these variabilities, low passage D1 cells were thawed (passage 3) and passaged serially until a much higher number (passage 34). Samples were taken every five passages and analyzed for alkaline phosphatase and triglyceride; also, the gene expression of both adipogenic and osteogenic markers was tested. The results indicate that the growth rate of these cells did slow down after passage 30. However, expression of the osteogenic characteristics seemed to cycle, with the highest levels seen at passage 4 and 24. The adipocyte expression levels remained the same throughout the study.

  14. MicroRNAs as Regulators of Adipogenic Differentiation of Mesenchymal Stem Cells

    DEFF Research Database (Denmark)

    Hamam, Dana; Ali, Dalia; Kassem, Moustapha;

    2015-01-01

    MicroRNAs (miRNAs) constitute complex regulatory network, fine tuning the expression of a myriad of genes involved in different biological and physiological processes, including stem cell differentiation. Mesenchymal stem cells (MSCs) are multipotent stem cells present in the bone marrow stroma......, and the stroma of many other tissues, and can give rise to a number of mesoderm-type cells including adipocytes and osteoblasts, which form medullary fat and bone tissues, respectively. The role of bone marrow fat in bone mass homeostasis is an area of intensive investigation with the aim of developing novel...... approaches for enhancing osteoblastic bone formation through inhibition of bone marrow fat formation. A number of recent studies have reported several miRNAs that enhance or inhibit adipogenic differentiation of MSCs and with potential use in microRNA-based therapy to regulate adipogenesis in the context...

  15. Cell Models and Their Application for Studying Adipogenic Differentiation in Relation to Obesity: A Review

    Science.gov (United States)

    Ruiz-Ojeda, Francisco Javier; Rupérez, Azahara Iris; Gomez-Llorente, Carolina; Gil, Angel; Aguilera, Concepción María

    2016-01-01

    Over the last several years, the increasing prevalence of obesity has favored an intense study of adipose tissue biology and the precise mechanisms involved in adipocyte differentiation and adipogenesis. Adipocyte commitment and differentiation are complex processes, which can be investigated thanks to the development of diverse in vitro cell models and molecular biology techniques that allow for a better understanding of adipogenesis and adipocyte dysfunction associated with obesity. The aim of the present work was to update the different animal and human cell culture models available for studying the in vitro adipogenic differentiation process related to obesity and its co-morbidities. The main characteristics, new protocols, and applications of the cell models used to study the adipogenesis in the last five years have been extensively revised. Moreover, we depict co-cultures and three-dimensional cultures, given their utility to understand the connections between adipocytes and their surrounding cells in adipose tissue. PMID:27376273

  16. Cell Models and Their Application for Studying Adipogenic Differentiation in Relation to Obesity: A Review.

    Science.gov (United States)

    Ruiz-Ojeda, Francisco Javier; Rupérez, Azahara Iris; Gomez-Llorente, Carolina; Gil, Angel; Aguilera, Concepción María

    2016-01-01

    Over the last several years, the increasing prevalence of obesity has favored an intense study of adipose tissue biology and the precise mechanisms involved in adipocyte differentiation and adipogenesis. Adipocyte commitment and differentiation are complex processes, which can be investigated thanks to the development of diverse in vitro cell models and molecular biology techniques that allow for a better understanding of adipogenesis and adipocyte dysfunction associated with obesity. The aim of the present work was to update the different animal and human cell culture models available for studying the in vitro adipogenic differentiation process related to obesity and its co-morbidities. The main characteristics, new protocols, and applications of the cell models used to study the adipogenesis in the last five years have been extensively revised. Moreover, we depict co-cultures and three-dimensional cultures, given their utility to understand the connections between adipocytes and their surrounding cells in adipose tissue. PMID:27376273

  17. Histone methyltransferases and demethylases:regulators in balancing osteogenic and adipogenic differentiation of mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Peng Deng; Qian-Ming Chen; Christine Hong; Cun-Yu Wang

    2015-01-01

    Mesenchymal stem cells (MSCs) are characterized by their self-renewing capacity and differentiation potential into multiple tissues. Thus, management of the differentiation capacities of MSCs is important for MSC-based regenerative medicine, such as craniofacial bone regeneration, and in new treatments for metabolic bone diseases, such as osteoporosis. In recent years, histone modification has been a growing topic in the field of MSC lineage specification, in which the Su(var)3–9, enhancer-of-zeste, trithorax (SET) domain-containing family and the Jumonji C (JmjC) domain-containing family represent the major histone lysine methyltransferases (KMTs) and histone lysine demethylases (KDMs), respectively. In this review, we summarize the current understanding of the epigenetic mechanisms by which SET domain-containing KMTs and JmjC domain-containing KDMs balance the osteogenic and adipogenic differentiation of MSCs.

  18. Transcription factor cooperativity in early adipogenic hotspots and super-enhancers

    DEFF Research Database (Denmark)

    Siersbæk, Rasmus; Rabiee, Atefeh; Nielsen, Ronni;

    2014-01-01

    It is becoming increasingly clear that transcription factors operate in complex networks through thousands of genomic binding sites, many of which bind several transcription factors. However, the extent and mechanisms of crosstalk between transcription factors at these hotspots remain unclear....... Using a combination of advanced proteomics and genomics approaches, we identify ∼12,000 transcription factor hotspots (∼400 bp) in the early phase of adipogenesis, and we find evidence of both simultaneous and sequential binding of transcription factors at these regions. We demonstrate that hotspots...... are highly enriched in large super-enhancer regions (several kilobases), which drive the early adipogenic reprogramming of gene expression. Our results indicate that cooperativity between transcription factors at the level of hotspots as well as super-enhancers is very important for enhancer activity...

  19. In vitro activity assays for MYST histone acetyltransferases and adaptation for high-throughput inhibitor screening

    Science.gov (United States)

    McCullough, Cheryl E.; Marmorstein, Ronen

    2016-01-01

    Lysine acetylation is a post-translational modification that is carried out by acetyltransferases. The MYST proteins form the largest and most diverse family of acetyltransferases, which regulate gene expression, DNA repair, and cell cycle homeostasis, among other activities, by acetylating both histone and non-histone proteins. This chapter will describe methods for the preparation and biochemical characterization of MYST family acetyltransferases, including protocols for the preparation of recombinant protein, enzyme assays for measuring steady state parameters and binding assays to measure cofactor and inhibitor binding. We also provide details on adapting these assays for high throughput screening for small molecule MYST inhibitors. This chapter seeks to prepare researchers for some hurdles that they may encounter when studying the MYST proteins so that there may be better opportunity to plan appropriate controls and obtain high quality data. PMID:27372752

  20. Hybrid adipogenic implants from adipose stem cells for soft tissue reconstruction in vivo.

    Science.gov (United States)

    Moioli, Eduardo K; Chen, Mo; Yang, Rujing; Shah, Bhranti; Wu, June; Mao, Jeremy J

    2010-11-01

    A critical barrier in tissue regeneration is scale-up. Bioengineered adipose tissue implants have been limited to ∼10  mm in diameter. Here, we devised a 40-mm hybrid implant with a cellular layer encapsulating an acellular core. Human adipose-derived stem cells (ASCs) were seeded in alginate. Poly(ethylene)glycol-diacrylate (PEGDA) was photopolymerized into 40-mm-diameter dome-shaped gel. Alginate-ASC suspension was painted onto PEGDA surface. Cultivation of hybrid constructs ex vivo in adipogenic medium for 28 days showed no delamination. Upon 4-week in vivo implantation in athymic rats, hybrid implants well integrated with host subcutaneous tissue and could only be surgically separated. Vascularized adipose tissue regenerated in the thin, painted alginate layer only if ASC-derived adipogenic cells were delivered. Contrastingly, abundant fibrous tissue filled ASC-free alginate layer encapsulating the acellular PEGDA core in control implants. Human-specific peroxisome proliferator-activated receptor-γ (PPAR-γ) was detected in human ASC-seeded implants. Interestingly, rat-specific PPAR-γ was absent in either human ASC-seeded or ASC-free implants. Glycerol content in ASC-delivered implants was significantly greater than that in ASC-free implants. Remarkably, rat-specific platelet/endothelial cell adhesion molecule (PECAM) was detected in both ASC-seeded and ASC-free implants, suggesting anastomosis of vasculature in bioengineered tissue with host blood vessels. Human nuclear staining revealed that a substantial number of adipocytes were of human origin, whereas endothelial cells of vascular wall were of chemaric human and nonhuman (rat host) origins. Together, hybrid implant appears to be a viable scale-up approach with volumetric retention attributable primarily to the acellular biomaterial core, and yet has a biologically viable cellular interface with the host. The present 40-mm soft tissue implant may serve as a biomaterial tissue expander for

  1. Nickel and Cobalt Resistance Engineered in Escherichia coli by Overexpression of Serine Acetyltransferase from the Nickel Hyperaccumulator Plant Thlaspi goesingense

    OpenAIRE

    Freeman, John L; Persans, Michael W.; Nieman, Ken; Salt, David E.

    2005-01-01

    The overexpression of serine acetyltransferase from the Ni-hyperaccumulating plant Thlaspi goesingense causes enhanced nickel and cobalt resistance in Escherichia coli. Furthermore, overexpression of T. goesingense serine acetyltransferase results in enhanced sensitivity to cadmium and has no significant effect on resistance to zinc. Enhanced nickel resistance is directly related to the constitutive overactivation of sulfur assimilation and glutathione biosynthesis, driven by the overproducti...

  2. p300 Acetyltransferase Regulates Androgen Receptor Degradation and PTEN-Deficient Prostate Tumorigenesis

    NARCIS (Netherlands)

    Zhong, J.; Ding, L.; Bohrer, L.R.; Pan, Y.; Liu, P.; Zhang, Jun; Sebo, T.J.; Karnes, R.J.; Tindall, D.J.; Deursen, J.M. van; Huang, H.

    2014-01-01

    Overexpression of the histone acetyltransferase p300 is implicated in the proliferation and progression of prostate cancer, but evidence of a causal role is lacking. In this study, we provide genetic evidence that this generic transcriptional coactivator functions as a positive modifier of prostate

  3. Reactivity of isothiazolones and isothiazolone-1-oxides in the inhibition of the PCAF histone acetyltransferase

    NARCIS (Netherlands)

    Ghizzoni, Massimo; Haisma, Hidde J.; Dekker, Frank J.

    2009-01-01

    Development of small molecule inhibitors of the histone acetyltransferase p300/CBP associated factor (PCAF) is relevant for oncology. The inhibition of the enzyme PCAF and proliferation of the cancer cell line HEP G2 by a series of 5-chloroisothiazolones was compared to a series of 5-chloroisothiazo

  4. Histone acetyltransferase PCAF is required for Hedgehog-Gli-dependent transcription and cancer cell proliferation

    DEFF Research Database (Denmark)

    Malatesta, Martina; Steinhauer, Cornelia; Mohammad, Faizaan;

    2013-01-01

    that the histone acetyltransferase PCAF/KAT2B is an important factor of the Hh pathway. Specifically, we show that PCAF depletion impairs Hh activity and reduces expression of Hh target genes. Consequently, PCAF downregulation in medulloblastoma and glioblastoma cells leads to decreased proliferation and increased...

  5. Comparative investigation of the xenobiotic metabolizing arylamine N-acetyltransferase enzyme family among fungi

    Science.gov (United States)

    Arylamine N-acetyltransferases (NATs) are xenobiotic metabolizing enzymes well-characterized in several bacteria and higher eukaryotes. The role of NATs in fungal biology has only recently been investigated. The NAT1 gene of Gibberella moniliformis was the first NAT cloned and characterized from fun...

  6. Adipogenic human adenovirus Ad-36 induces commitment, differentiation, and lipid accumulation in human adipose-derived stem cells

    DEFF Research Database (Denmark)

    Pasarica, Magdalena; Mashtalir, Nazar; McAllister, Emily J;

    2008-01-01

    Human adenovirus Ad-36 is causatively and correlatively linked with animal and human obesity, respectively. Ad-36 enhances differentiation of rodent preadipocytes, but its effect on adipogenesis in humans is unknown. To indirectly assess the role of Ad-36-induced adipogenesis in human obesity......, the effect of the virus on commitment, differentiation, and lipid accumulation was investigated in vitro in primary human adipose-derived stem/stromal cells (hASC). Ad-36 infected hASC in a time- and dose-dependent manner. Even in the presence of osteogenic media, Ad-36-infected hASC showed significantly...... greater lipid accumulation, suggestive of their commitment to the adipocyte lineage. Even in the absence of adipogenic inducers, Ad-36 significantly increased hASC differentiation, as indicated by a time-dependent expression of genes within the adipogenic cascade-CCAAT/Enhancer binding protein...

  7. ERK1 and ERK2 are involved in recruitment and maturation of human mesenchymal stem cells induced to adipogenic differentiation

    Institute of Scientific and Technical Information of China (English)

    Elisabetta Donzelli; Caterina Lucchini; Elisa Ballarini; Arianna Scuteri; Fabrizio Carini; Giovanni Tredici; Mariarosaria Miloso

    2011-01-01

    Adipocytes' biology and the mechanisms that control adipogenesis have gained importance because of the need to develop therapeutic strategies to control obesity and the related pathologies. Human mesenchymal stem cells (hMSCs), undifferentiated stem cells present in the bone marrow that are physiological precursors of adipocytes, were induced to adipogenic differentiation. The molecular mechanisms on the basis of the adipogenesis were evaluated, focusing on the MAPKinases ERK1 and ERK2, which are involved in many biological and cellular processes. ERK1 and ERK2 phosphorylation was reduced with different timing and intensity for the two isoforms in treated hMSCs in comparison with control cells until day 10 and then at 14-28 days, it reached the level of untreated cultures. The total amount of ERK1 was also decreased up to day 10 and then was induced to the level of untreated cultures, whereas the expression of ERK2 was not changed following adipogenic induction. Treatment with the specific ERK1/2 inhibitor U0126 during the whole differentiation period hampered hMSCs' adipogenic differentiation, as lipid droplets appeared in very few cells and were reduced in number and size. When U0126 was administered only during the initial phase of differentiation, the number of hMSCs recruited to adipogenesis was reduced while, when it was administered later, hMSCs did not acquire a mature adipocytic phenotype. ERK1 and ERK2 are important for hMSC adipogenic differentiation since any alteration to the correct timing of their phosphorylation affects either the recruitment into the differentiation program and the extent of their maturation.

  8. Different origin of adipogenic stem cells influences the response to antiretroviral drugs

    Energy Technology Data Exchange (ETDEWEB)

    Gibellini, Lara; De Biasi, Sara; Nasi, Milena; Carnevale, Gianluca; Pisciotta, Alessandra; Bianchini, Elena; Bartolomeo, Regina [Department of Surgery, Medicine, Dentistry and Morphological Sciences, University of Modena and Reggio Emilia School of Medicine, Via Campi 287, 41125 Modena (Italy); Polo, Miriam [Department of Pharmacology, University of Valencia, Av.da Blasco Ibáñez 15, Valencia (Spain); FISABIO–Hospital Universitario Dr. Peset, Av.da Gaspar Aguilar 90, Valencia (Spain); De Pol, Anto [Department of Surgery, Medicine, Dentistry and Morphological Sciences, University of Modena and Reggio Emilia School of Medicine, Via Campi 287, 41125 Modena (Italy); Dipartimento Sperimentale Interaziendale, Campus San Lazzaro, University of Modena and Reggio Emilia, 42122 Reggio Emilia (Italy); Pinti, Marcello [Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena (Italy); Cossarizza, Andrea, E-mail: andrea.cossarizza@unimore.it [Department of Surgery, Medicine, Dentistry and Morphological Sciences, University of Modena and Reggio Emilia School of Medicine, Via Campi 287, 41125 Modena (Italy); Dipartimento Sperimentale Interaziendale, Campus San Lazzaro, University of Modena and Reggio Emilia, 42122 Reggio Emilia (Italy)

    2015-10-01

    Lipodystrophy (LD) is a main side effect of antiretroviral therapy for HIV infection, and can be provoked by nucleoside reverse transcriptase inhibitors (NRTIs) and protease inhibitors (PIs). LD exists in different forms, characterized by fat loss, accumulation, or both, but its pathogenesis is still unclear. In particular, few data exist concerning the effects of antiretroviral drugs on adipocyte differentiation. Adipose tissue can arise either from mesenchymal stem cells (MSCs), that include bone marrow-derived MSCs (hBM-MSCs), or from ectodermal stem cells, that include dental pulp stem cells (hDPSCs). To analyze whether the embryonal origin of adipocytes might impact the occurrence of different phenotypes in LD, we quantified the effects of several antiretroviral drugs on the adipogenic differentiation of hBM-MSCs and hDPSCs. hBM-MSCs and hDPSCs were isolated from healthy donors. Cells were treated with 10 and 50 μM stavudine (d4T), efavirenz (EFV), atazanavir (ATV), ritonavir (RTV), and ATV-boosted RTV. Viability and adipogenesis were evaluated by staining with propidium iodide, oil red, and adipoRed; mRNA levels of genes involved in adipocyte differentiation, i.e. CCAAT/enhancer-binding protein alpha (CEBPα) and peroxisome proliferator-activated receptor gamma (PPARγ), and in adipocyte functions, i.e. fatty acid synthase (FASN), fatty acid binding protein-4 (FABP4), perilipin-1 (PLIN1) and 1-acylglycerol-3-phosphate O-acyltransferase-2 (AGPAT2), were quantified by real time PCR. We found that ATV, RTV, EFV, and ATV-boosted RTV, but not d4T, caused massive cell death in both cell types. EFV and d4T affected the accumulation of lipid droplets and induced changes in mRNA levels of genes involved in adipocyte functions in hBM-MSCs, while RTV and ATV had little effects. All drugs stimulated the accumulation of lipid droplets in hDPSCs. Thus, the adipogenic differentiation of human stem cells can be influenced by antiretroviral drugs, and depends, at least in

  9. Different origin of adipogenic stem cells influences the response to antiretroviral drugs

    International Nuclear Information System (INIS)

    Lipodystrophy (LD) is a main side effect of antiretroviral therapy for HIV infection, and can be provoked by nucleoside reverse transcriptase inhibitors (NRTIs) and protease inhibitors (PIs). LD exists in different forms, characterized by fat loss, accumulation, or both, but its pathogenesis is still unclear. In particular, few data exist concerning the effects of antiretroviral drugs on adipocyte differentiation. Adipose tissue can arise either from mesenchymal stem cells (MSCs), that include bone marrow-derived MSCs (hBM-MSCs), or from ectodermal stem cells, that include dental pulp stem cells (hDPSCs). To analyze whether the embryonal origin of adipocytes might impact the occurrence of different phenotypes in LD, we quantified the effects of several antiretroviral drugs on the adipogenic differentiation of hBM-MSCs and hDPSCs. hBM-MSCs and hDPSCs were isolated from healthy donors. Cells were treated with 10 and 50 μM stavudine (d4T), efavirenz (EFV), atazanavir (ATV), ritonavir (RTV), and ATV-boosted RTV. Viability and adipogenesis were evaluated by staining with propidium iodide, oil red, and adipoRed; mRNA levels of genes involved in adipocyte differentiation, i.e. CCAAT/enhancer-binding protein alpha (CEBPα) and peroxisome proliferator-activated receptor gamma (PPARγ), and in adipocyte functions, i.e. fatty acid synthase (FASN), fatty acid binding protein-4 (FABP4), perilipin-1 (PLIN1) and 1-acylglycerol-3-phosphate O-acyltransferase-2 (AGPAT2), were quantified by real time PCR. We found that ATV, RTV, EFV, and ATV-boosted RTV, but not d4T, caused massive cell death in both cell types. EFV and d4T affected the accumulation of lipid droplets and induced changes in mRNA levels of genes involved in adipocyte functions in hBM-MSCs, while RTV and ATV had little effects. All drugs stimulated the accumulation of lipid droplets in hDPSCs. Thus, the adipogenic differentiation of human stem cells can be influenced by antiretroviral drugs, and depends, at least in

  10. Genomic profiling reveals that transient adipogenic activation is a hallmark of mouse models of skeletal muscle regeneration.

    Directory of Open Access Journals (Sweden)

    Laura Lukjanenko

    Full Text Available The marbling of skeletal muscle by ectopic adipose tissue is a hallmark of many muscle diseases, including sarcopenia and muscular dystrophies, and generally associates with impaired muscle regeneration. Although the etiology and the molecular mechanisms of ectopic adipogenesis are poorly understood, fatty regeneration can be modeled in mice using glycerol-induced muscle damage. Using comprehensive molecular and histological profiling, we compared glycerol-induced fatty regeneration to the classical cardiotoxin (CTX-induced regeneration model previously believed to lack an adipogenic response in muscle. Surprisingly, ectopic adipogenesis was detected in both models, but was stronger and more persistent in response to glycerol. Importantly, extensive differential transcriptomic profiling demonstrated that glycerol induces a stronger inflammatory response and promotes adipogenic regulatory networks while reducing fatty acid β-oxidation. Altogether, these results provide a comprehensive mapping of gene expression changes during the time course of two muscle regeneration models, and strongly suggest that adipogenic commitment is a hallmark of muscle regeneration, which can lead to ectopic adipocyte accumulation in response to specific physio-pathological challenges.

  11. Perilipin Expression Reveals Adipogenic Potential of hADSCs inside Superporous Polymeric Cellular Delivery Systems

    Directory of Open Access Journals (Sweden)

    Sorina Dinescu

    2014-01-01

    Full Text Available Recent progress in tissue engineering and regenerative medicine envisages the use of cell-scaffold bioconstructs to best mimic the natural in vivo microenvironment. Our aim was not only to develop novel 3D porous scaffolds for regenerative applications by the association of gelatin (G, alginate (A, and polyacrylamide (PAA major assets but also to evaluate their in vitro potential to support human adipose-derived stem cells (hADSCs adipogenesis. G-A-PAA biomatrix investigated in this work is an interesting substrate combining the advantages of the three individual constituents, namely, biodegradability of G, hydrophilicity of A and PAA, superior elasticity at compression with respect to the G-A and PAA controls, and the capacity to generate porous scaffolds. hADSCs inside these novel interpenetrating polymer networks (IPNs were able to populate the entire scaffold structure and to display their characteristic spindle-like shape as a consequence of a good interaction with G component of the matrices. Additionally, hADSCs proved to display the capacity to differentiate towards mature adipocytes, to accumulate lipids inside their cytoplasm, and to express perilipin late adipogenic marker inside novel IPNs described in this study. On long term, this newly designed biomatrix aims to represent a stem cell delivery system product dedicated for modern regenerative strategies.

  12. Protocols for in vitro Differentiation of Human Mesenchymal Stem Cells into Osteogenic, Chondrogenic and Adipogenic Lineages.

    Science.gov (United States)

    Ciuffreda, Maria Chiara; Malpasso, Giuseppe; Musarò, Paola; Turco, Valentina; Gnecchi, Massimiliano

    2016-01-01

    Mesenchymal stem cells (MSC) possess high plasticity and the potential to differentiate into several different cell types; this characteristic has implications for cell therapy and reparative biotechnologies. MSC have been originally isolated from the bone marrow (BM-MSC), but they have been found also in other tissues such as adipose tissue, cord blood, synovium, skeletal muscle, and lung. MSC are able to differentiate in vitro and in vivo into several cell types such as bone, osteocytes, chondrocytes, adipocytes, and skeletal myocytes, just to name a few.During the last two decades, an increasing number of studies have proven the therapeutic potential of MSC for the treatment of neurodegenerative diseases, spinal cord and brain injuries, cardiovascular diseases, diabetes mellitus, and diseases of the skeleton. Their immuno-privileged profile allows both autologous and allogeneic use. For all these reasons, the scientific appeal of MSC is constantly on the rise.The identity of MSC is currently based on three main criteria: plastic-adherence capacity, defined epitope profile, and capacity to differentiate in vitro into osteocytes, chondrocytes, and adipocytes. Here, we describe standard protocols for the differentiation of BM-MSC into the osteogenic, chondrogenic, and adipogenic lineages. PMID:27236670

  13. Momordica charantia (bitter melon inhibits primary human adipocyte differentiation by modulating adipogenic genes

    Directory of Open Access Journals (Sweden)

    Nerurkar Vivek R

    2010-06-01

    Full Text Available Abstract Background Escalating trends of obesity and associated type 2 diabetes (T2D has prompted an increase in the use of alternative and complementary functional foods. Momordica charantia or bitter melon (BM that is traditionally used to treat diabetes and complications has been demonstrated to alleviate hyperglycemia as well as reduce adiposity in rodents. However, its effects on human adipocytes remain unknown. The objective of our study was to investigate the effects of BM juice (BMJ on lipid accumulation and adipocyte differentiation transcription factors in primary human differentiating preadipocytes and adipocytes. Methods Commercially available cryopreserved primary human preadipocytes were treated with and without BMJ during and after differentiation. Cytotoxicity, lipid accumulation, and adipogenic genes mRNA expression was measured by commercial enzymatic assay kits and semi-quantitative RT-PCR (RT-PCR. Results Preadipocytes treated with varying concentrations of BMJ during differentiation demonstrated significant reduction in lipid content with a concomitant reduction in mRNA expression of adipocyte transcription factors such as, peroxisome proliferator-associated receptor γ (PPARγ and sterol regulatory element-binding protein 1c (SREBP-1c and adipocytokine, resistin. Similarly, adipocytes treated with BMJ for 48 h demonstrated reduced lipid content, perilipin mRNA expression, and increased lipolysis as measured by the release of glycerol. Conclusion Our data suggests that BMJ is a potent inhibitor of lipogenesis and stimulator of lipolysis activity in human adipocytes. BMJ may therefore prove to be an effective complementary or alternative therapy to reduce adipogenesis in humans.

  14. Lipid Profiling of In Vitro Cell Models of Adipogenic Differentiation: Relationships With Mouse Adipose Tissues.

    Science.gov (United States)

    Liaw, Lucy; Prudovsky, Igor; Koza, Robert A; Anunciado-Koza, Rea V; Siviski, Matthew E; Lindner, Volkhard; Friesel, Robert E; Rosen, Clifford J; Baker, Paul R S; Simons, Brigitte; Vary, Calvin P H

    2016-09-01

    Our objective was to characterize lipid profiles in cell models of adipocyte differentiation in comparison to mouse adipose tissues in vivo. A novel lipid extraction strategy was combined with global lipid profiling using direct infusion and sequential precursor ion fragmentation, termed MS/MS(ALL) . Perirenal and inguinal white adipose tissue and interscapular brown adipose tissues from adult C57BL/6J mice were analyzed. 3T3-L1 preadipocytes, ear mesenchymal progenitor cells, and brown adipose-derived BAT-C1 cells were also characterized. Over 3000 unique lipid species were quantified. Principal component analysis showed that perirenal versus inguinal white adipose tissues varied in lipid composition of triacyl- and diacylglycerols, sphingomyelins, glycerophospholipids and, notably, cardiolipin CL 72:3. In contrast, hexosylceramides and sphingomyelins distinguished brown from white adipose. Adipocyte differentiation models showed broad differences in lipid composition among themselves, upon adipogenic differentiation, and with adipose tissues. Palmitoyl triacylglycerides predominate in 3T3-L1 differentiation models, whereas cardiolipin CL 72:1 and SM 45:4 were abundant in brown adipose-derived cell differentiation models, respectively. MS/MS(ALL) data suggest new lipid biomarkers for tissue-specific lipid contributions to adipogenesis, thus providing a foundation for using in vitro models of adipogenesis to reflect potential changes in adipose tissues in vivo. J. Cell. Biochem. 117: 2182-2193, 2016. © 2016 Wiley Periodicals, Inc.

  15. Adipogenic role of alternatively activated macrophages in β-adrenergic remodeling of white adipose tissue.

    Science.gov (United States)

    Lee, Yun-Hee; Kim, Sang-Nam; Kwon, Hyun-Jung; Maddipati, Krishna Rao; Granneman, James G

    2016-01-01

    De novo brown adipogenesis involves the proliferation and differentiation of progenitors, yet the mechanisms that guide these events in vivo are poorly understood. We previously demonstrated that treatment with a β3-adrenergic receptor (ADRB3) agonist triggers brown/beige adipogenesis in gonadal white adipose tissue following adipocyte death and clearance by tissue macrophages. The close physical relationship between adipocyte progenitors and tissue macrophages suggested that the macrophages that clear dying adipocytes might generate proadipogenic factors. Flow cytometric analysis of macrophages from mice treated with CL 316,243 identified a subpopulation that contained elevated lipid and expressed CD44. Lipidomic analysis of fluorescence-activated cell sorting-isolated macrophages demonstrated that CD44+ macrophages contained four- to five-fold higher levels of the endogenous peroxisome-proliferator activated receptor gamma (PPARγ) ligands 9-hydroxyoctadecadienoic acid (HODE), and 13-HODE compared with CD44- macrophages. Gene expression profiling and immunohistochemistry demonstrated that ADRB3 agonist treatment upregulated expression of ALOX15, the lipoxygenase responsible for generating 9-HODE and 13-HODE. Using an in vitro model of adipocyte efferocytosis, we found that IL-4-primed tissue macrophages accumulated lipid from dying fat cells and upregulated expression of Alox15. Furthermore, treatment of differentiating adipocytes with 9-HODE and 13-HODE potentiated brown/beige adipogenesis. Collectively, these data indicate that noninflammatory removal of adipocyte remnants and coordinated generation of PPARγ ligands by M2 macrophages provides localized adipogenic signals to support de novo brown/beige adipogenesis.

  16. Multiphoton fluorescence lifetime imaging of metabolic status in mesenchymal stem cell during adipogenic differentiation

    Science.gov (United States)

    Meleshina, A. V.; Dudenkova, V. V.; Shirmanova, M. V.; Bystrova, A. S.; Zagaynova, E. V.

    2016-03-01

    Non-invasive imaging of cell metabolism is a valuable approach to assess the efficacy of stem cell therapy and understand the tissue development. In this study we analyzed metabolic trajectory of the mesenchymal stem cells (MCSs) during differentiation into adipocytes by measuring fluorescence lifetimes of free and bound forms of the reduced nicotinamide adenine dinucleotide (NAD(P)H) and flavine adenine dinucleotide (FAD). Undifferentiated MSCs and MSCs on the 5, 12, 19, 26 days of differentiation were imaged on a Zeiss 710 microscope with fluorescence lifetime imaging (FLIM) system B&H (Germany). Fluorescence of NAD(P)H and FAD was excited at 750 nm and 900 nm, respectively, by a femtosecond Ti:sapphire laser and detected in a range 455-500 nm and 500-550 nm, correspondingly. We observed the changes in the NAD(P)H and FAD fluorescence lifetimes and their relative contributions in the differentiated adipocytes compare to undifferentiated MSCs. Increase of fluorescence lifetimes of the free and bound forms of NAD(P)H and the contribution of protein-bound NAD(P)H was registered, that can be associated with a metabolic switch from glycolysis to oxidative phosphorylation and/or synthesis of lipids in adipogenically differentiated MSCs. We also found that the contribution of protein-bound FAD decreased during differentiation. After carrying out appropriate biochemical measurements, the observed changes in cellular metabolism can potentially serve to monitor stem cell differentiation by FLIM.

  17. Cell-mediated remodeling of biomimetic encapsulating hydrogels triggered by adipogenic differentiation of adipose stem cells

    Science.gov (United States)

    Clevenger, Tracy N; Luna, Gabriel; Boctor, Daniel; Fisher, Steven K; Clegg, Dennis O

    2016-01-01

    One of the most common regenerative therapies is autologous fat grafting, which frequently suffers from unexpected volume loss. One approach is to deliver adipose stem cells encapsulated in the engineered hydrogels supportive of cell survival, differentiation, and integration after transplant. We describe an encapsulating, biomimetic poly(ethylene)-glycol hydrogel, with embedded peptides for attachment and biodegradation. Poly(ethylene)-glycol hydrogels containing an Arg–Gly–Asp attachment sequence and a matrix metalloprotease 3/10 cleavage site supported adipose stem cell survival and showed remodeling initiated by adipogenic differentiation. Arg–Gly–Asp–matrix metalloprotease 3/10 cleavage site hydrogels showed an increased number and area of lacunae or holes after adipose stem cell differentiation. Image analysis of adipose stem cells in Arg–Gly–Asp–matrix metalloprotease 3/10 cleavage site hydrogels showed larger Voronoi domains, while cell density remained unchanged. The differentiated adipocytes residing within these newly remodeled spaces express proteins and messenger RNAs indicative of adipocytic differentiation. These engineered scaffolds may provide niches for stem cell differentiation and could prove useful in soft tissue regeneration. PMID:27733898

  18. Adipogenic role of alternatively activated macrophages in β-adrenergic remodeling of white adipose tissue.

    Science.gov (United States)

    Lee, Yun-Hee; Kim, Sang-Nam; Kwon, Hyun-Jung; Maddipati, Krishna Rao; Granneman, James G

    2016-01-01

    De novo brown adipogenesis involves the proliferation and differentiation of progenitors, yet the mechanisms that guide these events in vivo are poorly understood. We previously demonstrated that treatment with a β3-adrenergic receptor (ADRB3) agonist triggers brown/beige adipogenesis in gonadal white adipose tissue following adipocyte death and clearance by tissue macrophages. The close physical relationship between adipocyte progenitors and tissue macrophages suggested that the macrophages that clear dying adipocytes might generate proadipogenic factors. Flow cytometric analysis of macrophages from mice treated with CL 316,243 identified a subpopulation that contained elevated lipid and expressed CD44. Lipidomic analysis of fluorescence-activated cell sorting-isolated macrophages demonstrated that CD44+ macrophages contained four- to five-fold higher levels of the endogenous peroxisome-proliferator activated receptor gamma (PPARγ) ligands 9-hydroxyoctadecadienoic acid (HODE), and 13-HODE compared with CD44- macrophages. Gene expression profiling and immunohistochemistry demonstrated that ADRB3 agonist treatment upregulated expression of ALOX15, the lipoxygenase responsible for generating 9-HODE and 13-HODE. Using an in vitro model of adipocyte efferocytosis, we found that IL-4-primed tissue macrophages accumulated lipid from dying fat cells and upregulated expression of Alox15. Furthermore, treatment of differentiating adipocytes with 9-HODE and 13-HODE potentiated brown/beige adipogenesis. Collectively, these data indicate that noninflammatory removal of adipocyte remnants and coordinated generation of PPARγ ligands by M2 macrophages provides localized adipogenic signals to support de novo brown/beige adipogenesis. PMID:26538237

  19. Nickel and cobalt resistance engineered in Escherichia coli by overexpression of serine acetyltransferase from the nickel hyperaccumulator plant Thlaspi goesingense.

    Science.gov (United States)

    Freeman, John L; Persans, Michael W; Nieman, Ken; Salt, David E

    2005-12-01

    The overexpression of serine acetyltransferase from the Ni-hyperaccumulating plant Thlaspi goesingense causes enhanced nickel and cobalt resistance in Escherichia coli. Furthermore, overexpression of T. goesingense serine acetyltransferase results in enhanced sensitivity to cadmium and has no significant effect on resistance to zinc. Enhanced nickel resistance is directly related to the constitutive overactivation of sulfur assimilation and glutathione biosynthesis, driven by the overproduction of O-acetyl-L-serine, the product of serine acetyltransferase and a positive regulator of the cysteine regulon. Nickel in the serine acetyltransferase-overexpressing strains is not detoxified by coordination or precipitation with sulfur, suggesting that glutathione is involved in reducing the oxidative damage imposed by nickel. PMID:16332856

  20. The histone acetyltransferase p300 inhibitor C646 reduces pro-inflammatory gene expression and inhibits histone deacetylases

    NARCIS (Netherlands)

    van den Bosch, Thea; Boichenko, Alexander; Leus, Niek G J; Ourailidou, Maria Eleni; Wapenaar, Hannah; Rotili, Dante; Mai, Antonello; Imhof, Axel; Bischoff, Rainer; Haisma, Hidde J; Dekker, Frank J

    2016-01-01

    Lysine acetylations are reversible posttranslational modifications of histone and non-histone proteins that play important regulatory roles in signal transduction cascades and gene expression. Lysine acetylations are regulated by histone acetyltransferases as writers and histone deacetylases as eras

  1. Inhibition of Lysine Acetyltransferase KAT3B/p300 Activity by a Naturally Occurring Hydroxynaphthoquinone, Plumbagin*

    OpenAIRE

    Ravindra, Kodihalli C.; Selvi, B. Ruthrotha; Arif, Mohammed; Reddy, B. A. Ashok; Thanuja, Gali R.; Agrawal, Shipra; Pradhan, Suman Kalyan; Nagashayana, Natesh; Dasgupta, Dipak; Tapas K. Kundu

    2009-01-01

    Lysine acetyltransferases (KATs), p300 (KAT3B), and its close homologue CREB-binding protein (KAT3A) are probably the most widely studied KATs with well documented roles in various cellular processes. Hence, the dysfunction of p300 may result in the dysregulation of gene expression leading to the manifestation of many disorders. The acetyltransferase activity of p300/CREB-binding protein is therefore considered as a target for new generation therapeutics. We describe here a natural compound, ...

  2. Purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3

    DEFF Research Database (Denmark)

    Kubiak, Xavier Jean Philippe; Pluvinage, Benjamin; Li de la Sierra-Gallay, Inès;

    2012-01-01

    Arylamine N-acetyltransferases (NATs) are xenobiotic metabolizing enzymes (XMEs) that catalyze the acetylation of arylamines. All functional NATs described to date possess a strictly conserved Cys-His-Asp catalytic triad. Here, the purification, crystallization and preliminary X-ray characterizat......Arylamine N-acetyltransferases (NATs) are xenobiotic metabolizing enzymes (XMEs) that catalyze the acetylation of arylamines. All functional NATs described to date possess a strictly conserved Cys-His-Asp catalytic triad. Here, the purification, crystallization and preliminary X...

  3. Expression profiling of S. pombe acetyltransferase mutants identifies redundant pathways of gene regulation

    Directory of Open Access Journals (Sweden)

    Wright Anthony PH

    2010-01-01

    Full Text Available Abstract Background Histone acetyltransferase enzymes (HATs are implicated in regulation of transcription. HATs from different families may overlap in target and substrate specificity. Results We isolated the elp3+ gene encoding the histone acetyltransferase subunit of the Elongator complex in fission yeast and characterized the phenotype of an Δelp3 mutant. We examined genetic interactions between Δelp3 and two other HAT mutants, Δmst2 and Δgcn5 and used whole genome microarray analysis to analyze their effects on gene expression. Conclusions Comparison of phenotypes and expression profiles in single, double and triple mutants indicate that these HAT enzymes have overlapping functions. Consistent with this, overlapping specificity in histone H3 acetylation is observed. However, there is no evidence for overlap with another HAT enzyme, encoded by the essential mst1+ gene.

  4. Histone acetyltransferases and deacetylases: molecular and clinical implications to gastrointestinal carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Wei-Jian Sun; Xiang Zhou; Ji-Hang Zheng; Ming-Dong Lu; Jian-Yun Nie; Xiang-Jiao Yang; Zhi-Qiang Zheng

    2012-01-01

    Histone acetyltransferases and deacetylases are two groups of enzymes whose opposing activities govern the dynamic levels of reversible acetylation on specific lysine residues of histones and many other proteins.Gastrointestinal (GI) carcinogenesis is a major cause of morbidity and mortality worldwide.In addition to genetic and environmental factors,the role of epigenetic abnormalities such as aberrant histone acetylation has been recognized to be pivotal in regulating benign tumorigenesis and eventual malignant transformation.Here we provide an overview of histone acetylation,list the major groups of histone acetyltransferases and deacetylases,and cover in relatively more details the recent studies that suggest the links of these enzymes to GI carcinogenesis.As potential novel therapeutics for GI and other cancers,histone deacetylase inhibitors are also discussed.

  5. [Histochemistry and choline acetyltransferase in cat spinal cord and spinal ganglia].

    Science.gov (United States)

    Motavkin, P A; Okhotin, V E

    1978-09-01

    Cytochemical activity of choline acetyltransferase has been studied in the pericaryon of motor neurons of the spinal enlargement and sensitive neurocytes of the intervertebral ganglia in the cat by means of Burt's method. It has been demonstrated that cytoplasm of all motor neurons positively reacts with acetyl KoA. According to the activity of choline acetyltransferase, four groups of neurons have been determined. In cerebrospinal ganglia, the enzyme is present in 58% of pseudounipolar cells, which seem to be cholinergic neurocytes. It has been stated that for all nonspecific reactions the presence of massive and dense residue in all the neurons, walls of small blood vessels and sometimes in astrocytes is a characteristic feature. PMID:718431

  6. Atypical antipsychotics induce both proinflammatory and adipogenic gene expression in human adipocytes in vitro

    International Nuclear Information System (INIS)

    Highlights: • Antipsychotics modulate the expression of adipogenic genes in human adipocytes. • Secretion of proinflammatory cytokine IL8 and MCP-1 is induced by antipsychotics. • Adipocyte-dependent inflammatory abnormality could develop during chronic treatment. • Infiltrated macrophages would further enhance proinflammatory cytokine production. - Abstract: Schizophrenia requires lifelong treatment, potentially causing systemic changes in metabolic homeostasis. In the clinical setting, antipsychotic treatment may differentially lead to weight gain among individual patients, although the molecular determinants of such adverse effects are currently unknown. In this study, we investigated changes in the expression levels of critical regulatory genes of adipogenesis, lipid metabolism and proinflammatory genes during the differentiation of primary human adipose-derived stem cells (ADSCs). These cells were isolated from patients with body mass indices <25 and treated with the second-generation antipsychotics olanzapine, ziprasidone, clozapine, quetiapine, aripiprazole and risperidone and the first-generation antipsychotic haloperidol. We found that antipsychotics exhibited a marked effect on key genes involved in the regulation of cell cycle, signal transduction, transcription factors, nuclear receptors, differentiation markers and metabolic enzymes. In particular, we observed an induction of the transcription factor NF-KB1 and NF-KB1 target genes in adipocytes in response to these drugs, including the proinflammatory cytokines TNF-α, IL-1β, IL-8 and MCP-1. In addition, enhanced secretion of both IL8 and MCP-1 was observed in the supernatant of these cell cultures. In addition to their remarkable stimulatory effects on proinflammatory gene transcription, three of the most frequently prescribed antipsychotic drugs, clozapine, quetiapine and aripiprazole, also induced the expression of essential adipocyte differentiation genes and the adipocyte hormones leptin

  7. Distinct populations of adipogenic and myogenic Myf5-lineage progenitors in white adipose tissues.

    Science.gov (United States)

    Shan, Tizhong; Liang, Xinrong; Bi, Pengpeng; Zhang, Pengpeng; Liu, Weiyi; Kuang, Shihuan

    2013-08-01

    Brown adipose tissues (BAT) are derived from a myogenic factor 5 (Myf5)-expressing cell lineage and white adipose tissues (WAT) predominantly arise from non-Myf5 lineages, although a subpopulation of adipocytes in some WAT depots can be derived from the Myf5 lineage. However, the functional implication of the Myf5- and non-Myf5-lineage cells in WAT is unclear. We found that the Myf5-lineage constitution in subcutaneous WAT depots is negatively correlated to the expression of classical BAT and newly defined beige/brite adipocyte-specific genes. Consistently, fluorescent-activated cell sorting (FACS)-purified Myf5-lineage adipo-progenitors give rise to adipocytes expressing lower levels of BAT-specific Ucp1, Prdm16, Cidea, and Ppargc1a genes and beige adipocyte-specific CD137, Tmem26, and Tbx1 genes compared with the non-Myf5-lineage adipocytes from the same depots. Ablation of the Myf5-lineage progenitors in WAT stromal vascular cell (SVC) cultures leads to increased expression of BAT and beige cell signature genes. Strikingly, the Myf5-lineage cells in WAT are heterogeneous and contain distinct adipogenic [stem cell antigen 1(Sca1)-positive] and myogenic (Sca1-negative) progenitors. The latter differentiate robustly into myofibers in vitro and in vivo, and they restore dystrophin expression after transplantation into mdx mouse, a model for Duchenne muscular dystrophy. These results demonstrate the heterogeneity and functional differences of the Myf5- and non-Myf5-lineage cells in the white adipose tissue.

  8. Atypical antipsychotics induce both proinflammatory and adipogenic gene expression in human adipocytes in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Sárvári, Anitta K., E-mail: anittasarvari@med.unideb.hu [Department of Biochemistry and Molecular Biology, Medical and Health Science Center, University of Debrecen, Debrecen (Hungary); Veréb, Zoltán, E-mail: jzvereb@gmail.com [Department of Biochemistry and Molecular Biology, Medical and Health Science Center, University of Debrecen, Debrecen (Hungary); Uray, Iván P., E-mail: ipuray@mdanderson.org [Clinical Cancer Prevention Department, The University of Texas, MD Anderson Cancer Center, Houston, TX (United States); Fésüs, László, E-mail: fesus@med.unideb.hu [Department of Biochemistry and Molecular Biology, Medical and Health Science Center, University of Debrecen, Debrecen (Hungary); MTA DE Apoptosis, Genomics and Stem Cell Research Group of the Hungarian Academy of Sciences (Hungary); Balajthy, Zoltán, E-mail: balajthy@med.unideb.hu [Department of Biochemistry and Molecular Biology, Medical and Health Science Center, University of Debrecen, Debrecen (Hungary)

    2014-08-08

    Highlights: • Antipsychotics modulate the expression of adipogenic genes in human adipocytes. • Secretion of proinflammatory cytokine IL8 and MCP-1 is induced by antipsychotics. • Adipocyte-dependent inflammatory abnormality could develop during chronic treatment. • Infiltrated macrophages would further enhance proinflammatory cytokine production. - Abstract: Schizophrenia requires lifelong treatment, potentially causing systemic changes in metabolic homeostasis. In the clinical setting, antipsychotic treatment may differentially lead to weight gain among individual patients, although the molecular determinants of such adverse effects are currently unknown. In this study, we investigated changes in the expression levels of critical regulatory genes of adipogenesis, lipid metabolism and proinflammatory genes during the differentiation of primary human adipose-derived stem cells (ADSCs). These cells were isolated from patients with body mass indices <25 and treated with the second-generation antipsychotics olanzapine, ziprasidone, clozapine, quetiapine, aripiprazole and risperidone and the first-generation antipsychotic haloperidol. We found that antipsychotics exhibited a marked effect on key genes involved in the regulation of cell cycle, signal transduction, transcription factors, nuclear receptors, differentiation markers and metabolic enzymes. In particular, we observed an induction of the transcription factor NF-KB1 and NF-KB1 target genes in adipocytes in response to these drugs, including the proinflammatory cytokines TNF-α, IL-1β, IL-8 and MCP-1. In addition, enhanced secretion of both IL8 and MCP-1 was observed in the supernatant of these cell cultures. In addition to their remarkable stimulatory effects on proinflammatory gene transcription, three of the most frequently prescribed antipsychotic drugs, clozapine, quetiapine and aripiprazole, also induced the expression of essential adipocyte differentiation genes and the adipocyte hormones leptin

  9. Heat stress enhances adipogenic differentiation of subcutaneous fat depot-derived porcine stromovascular cells.

    Science.gov (United States)

    Qu, H; Donkin, S S; Ajuwon, K M

    2015-08-01

    Heat stress (HS) results from excessive heat load on animals such that all adaptive mechanisms used to dissipate the heat do not return the body to normal body temperature. In pigs, HS results in increased fat deposition compared with pair-fed animals in a thermoneutral environment. Although there is evidence that HS increases activity of lipoprotein lipase (LPL) in adipose tissue of heat stressed pigs, the fundamental causes of the increased adiposity are still unknown. It remains unclear whether HS directly alters metabolism in adipocytes. Therefore, to understand the mechanism of HS effects on porcine adipocytes, we used an in vitro adipocyte differentiation model to characterize cellular responses that occur during differentiation of pig adipocytes. Preadipocytes (stromovascular cells) were differentiated for 9 d at a normal (37°C) or HS (41.5°C) temperature under 5% CO. Expressions of HS genes such as heat shock proteins (HSP; HSP27, HSP60, HSP70, and HSP90), adipogenic markers peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding proteins α (C/EBPα), fatty acid synthase (FAS), adipocyte protein 2 (aP2), fatty acid translocase 36 (CD36), fatty acid transport protein 4 (FATP4), fatty acid transport protein 6 (FATP6), LPL, glucose transporter protein type 4 (GLUT4), phosphoenolpyruvate carboxykinase 1 (PCK1 or PEPCK-C), and glycerol kinase (GK) and adipokines (adiponectin and leptin) were determined by real-time-PCR and immunoblotting or ELISA. Cellular triglyceride (TAG) and ATP concentrations were also determined. As expected, HS increased ( CD36, FATP4, FATP6, LPL, GLUT4, PCK1, and GK). This is supported by increased cellular TAG under HS. Therefore, HS promotes increased adipocyte TAG storage, perhaps through upregulation of genes involved in fatty acid uptake and TAG synthesis. PMID:26440163

  10. N-acetyltransferase 2 genetic polymorphism: Effects of carcinogen and haplotype on urinary bladder cancer risk

    OpenAIRE

    Hein, David W.

    2006-01-01

    A role for the N-acetyltransferase 2 (NAT2) genetic polymorphism in cancer risk has been the subject of numerous studies. Although comprehensive reviews of the NAT2 acetylation polymorphism have been published elsewhere, the objective of this paper is to briefly highlight some important features of the NAT2 acetylation polymorphism that are not universally accepted to better understand the role of NAT2 polymorphism in carcinogenic risk assessment. NAT2 slow acetylator phenotype(s) infer a con...

  11. Synthesis of 4′-aminopantetheine and derivatives to probe aminoglycoside N-6′-acetyltransferase

    OpenAIRE

    Yan, Xuxu; Akinnusi, T. Olukayode; Larsen, Aaron T.; Auclair, Karine

    2011-01-01

    A convenient synthesis of 4′-aminopantetheine from commercial D-pantethine is reported. The amino group was introduced by reductive amination in order to avoid substitution at a sterically congested position. Derivatives of 4′-aminopantetheine were also prepared to evaluate the effect of O-to-N substitution on inhibitors of the resistance-causing enzyme aminoglycoside N-6′-acetyltransferase. The biological results combined with docking studies indicate that in spite of its reported unusual fl...

  12. Response of ATP sulfurylase and serine acetyltransferase towards cadmium in hyperaccumulator Sedum alfredii Hance*

    OpenAIRE

    Guo, Wei-Dong; Liang, Jun; Yang, Xiao-e; Chao, Yue-en; Feng, Ying

    2009-01-01

    We studied the responses of the activities of adenosine-triphosphate (ATP) sulfurylase (ATPS) and serine acetyltransferase (SAT) to cadmium (Cd) levels and treatment time in hyperaccumulating ecotype (HE) Sedum alfredii Hance, as compared with its non-hyperaccumulating ecotype (NHE). The results show that plant growth was inhibited in NHE but promoted in HE when exposed to high Cd level. Cd concentrations in leaves and shoots rapidly increased in HE rather than in NHE, and they became much hi...

  13. Muscle-specific Deletion of Carnitine Acetyltransferase Compromises Glucose Tolerance and Metabolic Flexibility

    OpenAIRE

    Muoio, Deborah M.; Noland, Robert C.; Kovalik, Jean-Paul; Seiler, Sarah E.; Davies, Michael N.; DeBalsi, Karen L.; Ilkayeva, Olga R.; Stevens, Robert D.; Kheterpal, Indu; Zhang, Jingying; Jeffrey D Covington; Bajpeyi, Sudip; Ravussin, Eric; Kraus, William; Koves, Timothy R.

    2012-01-01

    The concept of “metabolic inflexibility” was first introduced to describe the failure of insulin resistant human subjects to appropriately adjust mitochondrial fuel selection in response to nutritional cues. This phenomenon has since gained increasing recognition as a core component of the metabolic syndrome, but the underlying mechanisms have remained elusive. Here, we identify an essential role for the mitochondrial matrix enzyme, carnitine acetyltransferase (CrAT), in regulating substrate ...

  14. GCN5 Acetyltransferase Inhibits PGC1α-induced Hepatitis B Virus Biosynthesis

    Institute of Scientific and Technical Information of China (English)

    Xiaohui Tian; Fei Zhao; Zhikui Cheng; Ming Zhou; Xiaoguang Zhi; Jiafu Li; Kanghong Hu

    2013-01-01

    Hepatitis B virus (HBV) biosynthesis is primarily restricted to hepatocytes due to the goveming of liver-enriched nuclear receptors (NRs) on viral RNA synthesis.The liver-enriched NR hepatocyte nuclear factor 4α (HNF4α),the key regulator of genes implicated in hepatic glucose metabolism,is also a primary determinant of HBV pregenomic RNA synthesis and HBV replication.Peroxisome proliferator-activated receptor-γ coactivator lα (PGC1α) coactivates and further enhances the effect of HNF4α on HBV biosynthesis.Here,we showed that the acetyltransferase General Control Non-repressed Protein 5 (GCN5) acetylated PGC1α,leading to alteration of PGC1α from a transcriptionally active state into an inactive state.As a result,the coactivation activity of PGClα on HBV transcription and replication was suppressed.Apparently,an acetylation site mutant of PGC 1α (PGC1αR13) still had coactivation activity as GCN5 could not suppress the coactivation activity of the mutant.Moreover,a catalytically inactive acetyltransferase mutant GCN5m,due to the loss of acetylation activity,failed to inhibit the coactivation function of PGC 1α in HBV biosynthesis.Our results demonstrate that GCN5,through its acetyltransferase activity,inhibits PGClα-induced enhancement of HBV transcription and replication both in vitro and in vivo.

  15. Depletion of histone demethylase KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of stem cells from apical papilla

    International Nuclear Information System (INIS)

    Mesenchymal stem cells (MSCs) are a reliable resource for tissue regeneration, but the molecular mechanism underlying directed differentiation remains unclear; this has restricted potential MSC applications. The histone demethylase, lysine (K)-specific demethylase 2A (KDM2A), is evolutionarily conserved and ubiquitously expressed members of the JmjC-domain-containing histone demethylase family. A previous study determined that KDM2A can regulate the cell proliferation and osteo/dentinogenic differentiation of MSCs. It is not known whether KDM2A is involved in the other cell lineages differentiation of MSCs. Here, we show that depletion of KDM2A by short hairpin RNAs can enhance adipogenic and chondrogenic differentiation potentials in human stem cells from apical papilla (SCAPs). We found that the stemness-related genes, SOX2, and the embryonic stem cell master transcription factor, NANOG were significantly increased after silence of KDM2A in SCAPs. Moreover, we found that knock-down of the KDM2A co-factor, BCOR also up-regulated the mRNA levels of SOX2 and NANOG. Furthermore, Chromatin immunoprecipitation assays demonstrate that silence of KDM2A increased the histone H3 Lysine 4 (H3K4) trimethylation in the SOX2 and NANOG locus and regulates its expression. In conclusion, our results suggested that depletion of KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of SCAPs by up-regulated SOX2 and NANOG, BCOR also involved in this regulation as co-factor, and provided useful information to understand the molecular mechanism underlying directed differentiation in MSCs. - Highlights: • Depletion of KDM2A enhances adipogenic/chondrogenic differentiation in SCAPs. • Depletion of KDM2A enhances the differentiation of SCAPs by activate SOX2 and NANOG. • Silence of KDM2A increases histone H3 Lysine 4 trimethylation in SOX2 and NANOG. • BCOR is co-factor of KDM2A involved in the differentiation regulation

  16. Beta-mecaptoethanol suppresses inflammation and induces adipogenic differentiation in 3T3-F442A murine preadipocytes.

    Directory of Open Access Journals (Sweden)

    Wen Guo

    Full Text Available Preadipocytes are present in adipose tissues throughout adult life that can proliferate and differentiate into mature adipocytes in response to environmental cues. Abnormal increase in adipocyte number or size leads to fat tissue expansion. However, it is now recognized that adipocyte hypertrophy is a greater risk factor for metabolic syndrome whereas fat tissue that continues to produce newer and smaller fat cells through preadipocyte differentiation is "metabolically healthy". Because adipocyte hypertrophy is often associated with increased oxidant stress and low grade inflammation, both are linked to disturbed cellular redox, we tested how preadipocyte differentiation may be regulated by beta-mercaptoethanol (BME, a pharmacological redox regulator and radical scavenger, using murine 3T3-F442A preadipocytes as the cell model. Effects of BME on adipogenesis were measured by microphotography, real-time PCR, and Western analysis. Our data demonstrated that preadipocyte differentiation could be regulated by extracellular BME. At an optimal concentration, BME enhanced expression of adipogenic gene markers and lipid accumulation. This effect was associated with BME-mediated down-regulation of inflammatory cytokine expression during early differentiation. BME also attenuated TNFalpha-induced activation of NFkappaB in differentiating preadipocytes and partially restored TNFalpha-mediated suppression on adipogenesis. Using a non-adipogenic HEK293 cell line transfected with luciferase reporter genes, we demonstrated that BME reduced basal and TNFalpha-induced NFkappaB activity and increased basal and ciglitazone-induced PPARgamma activity; both may contribute to the pro-adipogenic effect of BME in differentiating F442A preadipocytes.

  17. Depletion of histone demethylase KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of stem cells from apical papilla

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Rui [Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China); Yao, Rui [Department of Pediatrics, Stomatological Hospital of Nankai University, Tianjin 300041 (China); Du, Juan [Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China); Wang, Songlin [Molecular Laboratory for Gene Therapy and Tooth Regeneration, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China); Department of Biochemistry and Molecular Biology, Capital Medical University School of Basic Medical Sciences, Beijing 100069 (China); Fan, Zhipeng, E-mail: zpfan@ccmu.edu.cn [Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China)

    2013-11-01

    Mesenchymal stem cells (MSCs) are a reliable resource for tissue regeneration, but the molecular mechanism underlying directed differentiation remains unclear; this has restricted potential MSC applications. The histone demethylase, lysine (K)-specific demethylase 2A (KDM2A), is evolutionarily conserved and ubiquitously expressed members of the JmjC-domain-containing histone demethylase family. A previous study determined that KDM2A can regulate the cell proliferation and osteo/dentinogenic differentiation of MSCs. It is not known whether KDM2A is involved in the other cell lineages differentiation of MSCs. Here, we show that depletion of KDM2A by short hairpin RNAs can enhance adipogenic and chondrogenic differentiation potentials in human stem cells from apical papilla (SCAPs). We found that the stemness-related genes, SOX2, and the embryonic stem cell master transcription factor, NANOG were significantly increased after silence of KDM2A in SCAPs. Moreover, we found that knock-down of the KDM2A co-factor, BCOR also up-regulated the mRNA levels of SOX2 and NANOG. Furthermore, Chromatin immunoprecipitation assays demonstrate that silence of KDM2A increased the histone H3 Lysine 4 (H3K4) trimethylation in the SOX2 and NANOG locus and regulates its expression. In conclusion, our results suggested that depletion of KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of SCAPs by up-regulated SOX2 and NANOG, BCOR also involved in this regulation as co-factor, and provided useful information to understand the molecular mechanism underlying directed differentiation in MSCs. - Highlights: • Depletion of KDM2A enhances adipogenic/chondrogenic differentiation in SCAPs. • Depletion of KDM2A enhances the differentiation of SCAPs by activate SOX2 and NANOG. • Silence of KDM2A increases histone H3 Lysine 4 trimethylation in SOX2 and NANOG. • BCOR is co-factor of KDM2A involved in the differentiation regulation.

  18. Phenolic Composition, Antioxidant Activity and Anti-Adipogenic Effect of Hot Water Extract from Safflower (Carthamus tinctorius L.) Seed

    OpenAIRE

    Seok-Yeong Yu; Young-Jun Lee; Jong-Dai Kim; Suk-Nam Kang; Seong-Kap Lee; Jung-Young Jang; Hyo-Ku Lee; Jeong-Ho Lim; Ok-Hwan Lee

    2013-01-01

    This study was to evaluate the phenolic content and composition of Carthamus tinctorius L. seed extract (CSE) and to further assess its antioxidant and anti-adipogenic activities using various radical scavenging systems and 3T3-L1 cells. Our results show that the total phenolic and flavonoid contents of CSE were 126.0 ± 2.4 mg GAE/g and 62.2 ± 1.9 mg QE/g, respectively. The major phenolic compounds in CSE was (−)-epigallocatechin (109.62 mg/g), with a 4-hydroxy benzhydrazide derivative and ...

  19. Adipogenic Gene Expression in Gilthead Sea Bream Mesenchymal Stem Cells from Different Origin

    Science.gov (United States)

    Salmerón, Cristina; Riera-Heredia, Natàlia; Gutiérrez, Joaquim; Navarro, Isabel; Capilla, Encarnación

    2016-01-01

    During the last decades, adipogenesis has become an emerging field of study in aquaculture due to the relevance of the adipose tissue in many physiological processes and its connection with the endocrine system. In this sense, recent studies have translated into the establishment of preadipocyte culture models from several fish species, sometimes lacking information on the mRNA levels of adipogenic genes. Thus, the aim of this study was to determine the gene expression profile of gilthead sea bream (Sparus aurata) primary cultured mesenchymal stem cells (MSCs) from different origin (adipose tissue and vertebra bone) during adipogenesis. Both cell types differentiated into adipocyte-like cells, accumulating lipids inside their cytoplasm. Adipocyte differentiation of MSCs from adipose tissue resulted in downregulation of several adipocyte-related genes (such as lpl, hsl, pparα, pparγ and gapdh2) at day 4, gapdh1 at day 8, and fas and pparβ at day 12. In contrast, differences in lxrα mRNA expression were not observed, while g6pdh levels increased during adipocyte maturation. Gapdh and Pparγ protein levels were also detected in preadipocyte cultures; however, only the former increased its expression during adipogenesis. Moreover, differentiation of bone-derived cells into adipocytes also resulted in the downregulation of several adipocyte gene markers, such as fas and g6pdh at day 10 and hsl, pparβ, and lxrα at day 15. On the other hand, the osteogenic genes fib1a, mgp, and op remained stable, but an increase in runx2 expression at day 20 was observed. In summary, the present study demonstrates that gilthead sea bream MSCs, from both adipose tissue and bone, differentiate into adipocyte-like cells, although revealed some kind of species- and cell lineage-specific regulation with regards to gene expression. Present data also provide novel insights into some of the potential key genes controlling adipogenesis in gilthead sea bream that can help to better

  20. Adipogenic gene expression in gilthead sea bream mesenchymal stem cells from different origin

    Directory of Open Access Journals (Sweden)

    Cristina Salmerón

    2016-08-01

    Full Text Available During the last decades, adipogenesis has become an emerging field of study in aquaculture due to the relevance of the adipose tissue in many physiological processes and its connection with the endocrine system. In this sense, recent studies have translated into the establishment of preadipocyte culture models from several fish species, lacking sometimes information on the mRNA levels of adipogenic genes. Thus, the aim of this study was to determine the gene expression profile of gilthead sea bream (Sparus aurata primary cultured mesenchymal stem cells (MSCs from different origin (adipose tissue and vertebra bone during adipogenesis. Both cell types differentiated into adipocyte-like cells accumulating lipids inside their cytoplasm. Adipocyte differentiation of MSCs from adipose tissue resulted in down-regulation of several adipocyte-related genes (such as lpl, hsl, pparα, pparγ and gapdh2 at day 4, gapdh1 at day 8, and fas and pparβ at day 12. In contrast, differences in lxrα mRNA expression were not observed, while g6pdh levels increased during adipocyte maturation. Gapdh and Pparγ protein levels were also detected in preadipocyte cultures; however, only the former increased its expression during adipogenesis. Moreover, differentiation of bone-derived cells into adipocytes also resulted in the down-regulation of several adipocyte gene markers such as fas and g6pdh at day 10 and hsl, pparβ and lxrα at day 15. On the other hand, the osteogenic genes fib1a, mgp and op remained stable, but an increase in runx2 expression at day 20 was observed. In summary, the present study demonstrates that gilthead sea bream MSCs from both adipose tissue and bone differentiate into adipocyte-like cells, although revealed some kind of species- and cell lineage-specific regulation with regards to gene expression. Present data also provide novel insights into some of the potential key genes controlling adipogenesis in gilthead sea bream that can help to

  1. Adipogenic Gene Expression in Gilthead Sea Bream Mesenchymal Stem Cells from Different Origin.

    Science.gov (United States)

    Salmerón, Cristina; Riera-Heredia, Natàlia; Gutiérrez, Joaquim; Navarro, Isabel; Capilla, Encarnación

    2016-01-01

    During the last decades, adipogenesis has become an emerging field of study in aquaculture due to the relevance of the adipose tissue in many physiological processes and its connection with the endocrine system. In this sense, recent studies have translated into the establishment of preadipocyte culture models from several fish species, sometimes lacking information on the mRNA levels of adipogenic genes. Thus, the aim of this study was to determine the gene expression profile of gilthead sea bream (Sparus aurata) primary cultured mesenchymal stem cells (MSCs) from different origin (adipose tissue and vertebra bone) during adipogenesis. Both cell types differentiated into adipocyte-like cells, accumulating lipids inside their cytoplasm. Adipocyte differentiation of MSCs from adipose tissue resulted in downregulation of several adipocyte-related genes (such as lpl, hsl, pparα, pparγ and gapdh2) at day 4, gapdh1 at day 8, and fas and pparβ at day 12. In contrast, differences in lxrα mRNA expression were not observed, while g6pdh levels increased during adipocyte maturation. Gapdh and Pparγ protein levels were also detected in preadipocyte cultures; however, only the former increased its expression during adipogenesis. Moreover, differentiation of bone-derived cells into adipocytes also resulted in the downregulation of several adipocyte gene markers, such as fas and g6pdh at day 10 and hsl, pparβ, and lxrα at day 15. On the other hand, the osteogenic genes fib1a, mgp, and op remained stable, but an increase in runx2 expression at day 20 was observed. In summary, the present study demonstrates that gilthead sea bream MSCs, from both adipose tissue and bone, differentiate into adipocyte-like cells, although revealed some kind of species- and cell lineage-specific regulation with regards to gene expression. Present data also provide novel insights into some of the potential key genes controlling adipogenesis in gilthead sea bream that can help to better

  2. The Anti-Adipogenic Potential of COUP-TFII Is Mediated by Downregulation of the Notch Target Gene Hey1.

    Directory of Open Access Journals (Sweden)

    Ilse Scroyen

    Full Text Available Chicken ovalbumin upstream promoter transcription factor II (COUP-TFII belongs to the steroid/thyroid hormone receptor superfamily and may contribute to the pathogenesis of obesity. It has not conclusively been established, however, whether its role is pro- or anti-adipogenic.Gene silencing of Coup-tfII in 3T3-F442A preadipocytes resulted in enhanced differentiation into mature adipocytes. This was associated with upregulation of the Notch signaling target gene Hey1. A functional role of Hey1 was confirmed by gene silencing in 3T3-F442A preadipocytes, resulting in impaired differentiation. In vivo, de novo fat pad formation in NUDE mice was significantly stimulated following injection of preadipocytes with Coup-tfII gene silencing, but impaired with Hey1 gene silencing. Moreover, expression of Coup-tfII was lower and that of Hey1 higher in isolated adipocytes of obese as compared to lean adipose tissue.These in vitro and in vivo data support an anti-adipogenic role of COUP-TFII via downregulating the Notch signaling target gene Hey1.

  3. Effects of canola proteins and hydrolysates on adipogenic differentiation of C3H10T/2 mesenchymal stem cells.

    Science.gov (United States)

    Alashi, Adeola M; Blanchard, Christopher L; Mailer, Rodney J; Agboola, Samson O; Mawson, A John; Aluko, Rotimi E; Strappe, Padraig

    2015-10-15

    This study assessed the ability of canola protein isolate (CPI) and enzymatic hydrolysates (CPHs) to inhibit adipogenic differentiation of C3H10T1/2 murine mesenchymal stem cells in vitro. Cell viability was maintained at concentrations of 60 μg/ml of sample. Cells treated with Alcalase hydrolysate demonstrated a higher reduction in anti-adipogenic differentiation through quantitation by oil-red O staining. qPCR analysis showed that CPI and CPH-treated cells significantly inhibited PPARγ expression, a key transcription factor involved in adipocyte differentiation, as evident in an ∼ 60-80% fold reduction of PPARγ mRNA. Immunofluorescence staining for PPARγ protein also showed a reduced expression in some treated cells when compared to differentiated untreated cells. The 50% inhibition concentration (IC50) of CPI, CPHs and their membrane ultrafiltration fractions on pancreatic lipase (PL) activity ranged between 0.75 and 2.5 mg/ml, (p < 0.05) for the hydrolysed and unhydrolysed samples. These findings demonstrate that CPI and CPHs contain bioactive components which can modulate in vitro adipocyte differentiation. PMID:25952862

  4. Brown-like adipose progenitors derived from human induced pluripotent stem cells: Identification of critical pathways governing their adipogenic capacity

    Science.gov (United States)

    Hafner, Anne-Laure; Contet, Julian; Ravaud, Christophe; Yao, Xi; Villageois, Phi; Suknuntha, Kran; Annab, Karima; Peraldi, Pascal; Binetruy, Bernard; Slukvin, Igor I.; Ladoux, Annie; Dani, Christian

    2016-01-01

    Human induced pluripotent stem cells (hiPSCs) show great promise for obesity treatment as they represent an unlimited source of brown/brite adipose progenitors (BAPs). However, hiPSC-BAPs display a low adipogenic capacity compared to adult-BAPs when maintained in a traditional adipogenic cocktail. The reasons of this feature are unknown and hamper their use both in cell-based therapy and basic research. Here we show that treatment with TGFβ pathway inhibitor SB431542 together with ascorbic acid and EGF were required to promote hiPSCs-BAP differentiation at a level similar to adult-BAP differentiation. hiPSC-BAPs expressed the molecular identity of adult-UCP1 expressing cells (PAX3, CIDEA, DIO2) with both brown (ZIC1) and brite (CD137) adipocyte markers. Altogether, these data highlighted the critical role of TGFβ pathway in switching off hiPSC-brown adipogenesis and revealed novel factors to unlock their differentiation. As hiPSC-BAPs display similarities with adult-BAPs, it opens new opportunities to develop alternative strategies to counteract obesity. PMID:27577850

  5. Brown-like adipose progenitors derived from human induced pluripotent stem cells: Identification of critical pathways governing their adipogenic capacity.

    Science.gov (United States)

    Hafner, Anne-Laure; Contet, Julian; Ravaud, Christophe; Yao, Xi; Villageois, Phi; Suknuntha, Kran; Annab, Karima; Peraldi, Pascal; Binetruy, Bernard; Slukvin, Igor I; Ladoux, Annie; Dani, Christian

    2016-01-01

    Human induced pluripotent stem cells (hiPSCs) show great promise for obesity treatment as they represent an unlimited source of brown/brite adipose progenitors (BAPs). However, hiPSC-BAPs display a low adipogenic capacity compared to adult-BAPs when maintained in a traditional adipogenic cocktail. The reasons of this feature are unknown and hamper their use both in cell-based therapy and basic research. Here we show that treatment with TGFβ pathway inhibitor SB431542 together with ascorbic acid and EGF were required to promote hiPSCs-BAP differentiation at a level similar to adult-BAP differentiation. hiPSC-BAPs expressed the molecular identity of adult-UCP1 expressing cells (PAX3, CIDEA, DIO2) with both brown (ZIC1) and brite (CD137) adipocyte markers. Altogether, these data highlighted the critical role of TGFβ pathway in switching off hiPSC-brown adipogenesis and revealed novel factors to unlock their differentiation. As hiPSC-BAPs display similarities with adult-BAPs, it opens new opportunities to develop alternative strategies to counteract obesity. PMID:27577850

  6. The effect of low static magnetic field on osteogenic and adipogenic differentiation potential of human adipose stromal/stem cells

    Science.gov (United States)

    Marędziak, Monika; Śmieszek, Agnieszka; Tomaszewski, Krzysztof A.; Lewandowski, Daniel; Marycz, Krzysztof

    2016-01-01

    The aim of this work was to investigate the effects of static magnetic field (SMF) on the osteogenic properties of human adipose derived mesenchymal stem cells (hASCs). In this study in seven days viability assay we examined the impact of SMF on cells proliferation rate, population doubling time, and ability to form single-cell derived colonies. We have also examined cells' morphology, ultrastructure and osteogenic properties on the protein as well as mRNA level. We established a complex approach, which enabled us to obtain information about SMF and hASCs potential in the context of differentiation into osteogenic and adipogenic lineages. We demonstrated that SMF enhances both viability and osteogenic properties of hASCs through higher proliferation factor and shorter population doubling time. We have also observed asymmetrically positioned nuclei and organelles after SMF exposition. With regards to osteogenic properties we observed increased levels of osteogenic markers i.e. osteopontin, osteocalcin and increased ability to form osteonodules with positive reaction to Alizarin Red dye. We have also shown that SMF besides enhancing osteogenic properties of hASCs, simultaneously decreases their ability to differentiate into adipogenic lineage. Our results clearly show a direct influence of SMF on the osteogenic potential of hASCs. These results provide key insights into the role of SMF on their cellular fate and properties.

  7. The Wnt-target gene Dlk-1 is regulated by the Prmt5-associated factor Copr5 during adipogenic conversion

    Directory of Open Access Journals (Sweden)

    Conception Paul

    2015-02-01

    Full Text Available Protein arginine methyl transferase 5 (Prmt5 regulates various differentiation processes, including adipogenesis. Here, we investigated adipogenic conversion in cells and mice in which Copr5, a Prmt5- and histone-binding protein, was genetically invalidated. Compared to control littermates, the retroperitoneal white adipose tissue (WAT of Copr5 KO mice was slightly but significantly reduced between 8 and 16 week/old and contained fewer and larger adipocytes. Moreover, the adipogenic conversion of Copr5 KO embryoid bodies (EB and of primary embryo fibroblasts (Mefs was markedly delayed. Differential transcriptomic analysis identified Copr5 as a negative regulator of the Dlk-1 gene, a Wnt target gene involved in the control of adipocyte progenitors cell fate. Dlk-1 expression was upregulated in Copr5 KO Mefs and the Vascular Stromal Fraction (VSF of Copr5 KO WAT. Chromatin immunoprecipitation (ChIP show that the ablation of Copr5 has impaired both the recruitment of Prmt5 and β-catenin at the Dlk-1 promoter. Overall, our data suggest that Copr5 is involved in the transcriptional control exerted by the Wnt pathway on early steps of adipogenesis.

  8. New N-Acetyltransferase Fold in the Structure and Mechanism of the Phosphonate Biosynthetic Enzyme FrbF

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Brian; Cobb, Ryan E.; DeSieno, Matthew A.; Zhao, Huimin; Nair, Satish K. (UIUC)

    2015-10-15

    The enzyme FrbF from Streptomyces rubellomurinus has attracted significant attention due to its role in the biosynthesis of the antimalarial phosphonate FR-900098. The enzyme catalyzes acetyl transfer onto the hydroxamate of the FR-900098 precursors cytidine 5'-monophosphate-3-aminopropylphosphonate and cytidine 5'-monophosphate-N-hydroxy-3-aminopropylphosphonate. Despite the established function as a bona fide N-acetyltransferase, FrbF shows no sequence similarity to any member of the GCN5-like N-acetyltransferase (GNAT) superfamily. Here, we present the 2.0 {angstrom} resolution crystal structure of FrbF in complex with acetyl-CoA, which demonstrates a unique architecture that is distinct from those of canonical GNAT-like acetyltransferases. We also utilized the co-crystal structure to guide structure-function studies that identified the roles of putative active site residues in the acetyltransferase mechanism. The combined biochemical and structural analyses of FrbF provide insights into this previously uncharacterized family of N-acetyltransferases and also provide a molecular framework toward the production of novel N-acyl derivatives of FR-900098.

  9. Epigenetic change in kidney tumor: downregulation of histone acetyltransferase MYST1 in human renal cell carcinoma

    OpenAIRE

    Wang Yong; Zhang Rui; Wu Donglu; Lu Zhihua; Sun Wentao; Cai Yong; Wang Chunxi; Jin Jingji

    2013-01-01

    Abstract Background MYST1 (also known as hMOF), a member of the MYST family of histone acetyltransferases (HATs) as an epigenetic mark of active genes, is mainly responsible for histone H4K16 acetylation in the cells. Recent studies have shown that the abnormal gene expression of hMOF is involved in certain primary cancers. Here we examined the involvement of hMOF expression and histone H4K16 acetylation in primary renal cell carcinoma (RCC). Simultaneously, we investigated the correlation be...

  10. Synthesis of 4′-aminopantetheine and derivatives to probe aminoglycoside N-6′-acetyltransferase

    Science.gov (United States)

    Yan, Xuxu; Akinnusi, T. Olukayode; Larsen, Aaron T.; Auclair, Karine

    2011-01-01

    Summary A convenient synthesis of 4′-aminopantetheine from commercial D-pantethine is reported. The amino group was introduced by reductive amination in order to avoid substitution at a sterically congested position. Derivatives of 4′-aminopantetheine were also prepared to evaluate the effect of O-to-N substitution on inhibitors of the resistance-causing enzyme aminoglycoside N-6′-acetyltransferase. The biological results combined with docking studies indicate that in spite of its reported unusual flexibility and ability to adopt different folds, this enzyme is highly specific for AcCoA. PMID:21225062

  11. Synthesis of 4'-aminopantetheine and derivatives to probe aminoglycoside N-6'-acetyltransferase.

    Science.gov (United States)

    Yan, Xuxu; Akinnusi, T Olukayode; Larsen, Aaron T; Auclair, Karine

    2011-03-01

    A convenient synthesis of 4'-aminopantetheine from commercial D-pantethine is reported. The amino group was introduced by reductive amination in order to avoid substitution at a sterically congested position. Derivatives of 4'-aminopantetheine were also prepared to evaluate the effect of O-to-N substitution on inhibitors of the resistance-causing enzyme aminoglycoside N-6'-acetyltransferase. The biological results combined with docking studies indicate that in spite of its reported unusual flexibility and ability to adopt different folds, this enzyme is highly specific for AcCoA. PMID:21225062

  12. Characterization of an acetyltransferase that detoxifies aromatic chemicals in Legionella pneumophila

    DEFF Research Database (Denmark)

    Kubiak, Xavier Jean Philippe; Dervins-Ravault, Delphine; Pluvinage, Benjamin;

    2012-01-01

    at the molecular and functional levels. In the present paper we report the identification and biochemical and functional characterization of a unique acetyltransferase that metabolizes aromatic amine chemicals in three characterized clinical strains of L. pneumophila (Paris, Lens and Philadelphia). Strain...... to detoxify aromatic amine chemicals and grow in their presence. The present study provides a new enzymatic mechanism by which the opportunistic pathogen L. pneumophila biotransforms and detoxifies toxic aromatic chemicals. These data also emphasize the role of XMEs in the environmental adaptation of certain...

  13. Purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3

    International Nuclear Information System (INIS)

    B. cereus arylamine N-acetyltransferase 3 was expressed, purified and crystallized. X-ray diffraction data were collected to 2.42 Å resolution and the crystals belonged to the monoclinic space group C121. Arylamine N-acetyltransferases (NATs) are xenobiotic metabolizing enzymes (XMEs) that catalyze the acetylation of arylamines. All functional NATs described to date possess a strictly conserved Cys-His-Asp catalytic triad. Here, the purification, crystallization and preliminary X-ray characterization of Bacillus cereus arylamine N-acetyltransferase 3 [(BACCR)NAT3], a putative NAT isoenzyme that possesses a unique catalytic triad containing a glutamate residue, is reported. The crystal diffracted to 2.42 Å resolution and belonged to the monoclinic space group C121, with unit-cell parameters a = 90.44, b = 44.52, c = 132.98 Å, β = 103.8°

  14. Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression.

    Science.gov (United States)

    Warner, Dennis R; Smith, Scott C; Smolenkova, Irina A; Pisano, M Michele; Greene, Robert M

    2016-03-01

    p300 is a multifunctional transcriptional coactivator that interacts with numerous transcription factors and exhibits protein/histone acetyltransferase activity. Loss of p300 function in humans and in mice leads to craniofacial defects. In this study, we demonstrated that inhibition of p300 histone acetyltransferase activity with the compound, C646, altered the expression of several genes, including Cdh1 (E-cadherin) in mouse maxillary mesenchyme cells, which are the cells that give rise to the secondary palate. The increased expression of plasma membrane-bound E-cadherin was associated with reduced cytosolic β-catenin, that led to attenuated signaling through the canonical Wnt pathway. Furthermore, C646 reduced both cell proliferation and the migratory ability of these cells. These results suggest that p300 histone acetyltransferase activity is critical for Wnt-dependent palate mesenchymal cell proliferation and migration, both processes that play a significant role in morphogenesis of the palate.

  15. Germinated brown rice extract inhibits adipogenesis through the down-regulation of adipogenic genes in 3T3-L1 adipocytes.

    Science.gov (United States)

    Ho, Jin-Nyoung; Son, Mi-Eun; Lim, Won-Chul; Lim, Seung-Taik; Cho, Hong-Yon

    2013-09-01

    The aim of this study was to examine the anti-adipogenic effect of germinated brown rice methanol extract (GBR) in 3T3-L1 adipocytes. The GBR inhibited adipocyte differentiation was measured by Oil Red O staining and glycerol-3-phosphate dehydrogenase (GPDH) activity in a dose-dependent manner without initiating any cytotoxicity. The mRNA levels of adipogenic transcription factors such as CCAAT/enhancer binding protein (C/EBPα), proliferator-activated receptorγ (PPARγ), and sterol regulatory element-binding protein-1c (SREBP-1c), and adipogenic genes, such as fatty acid synthase (FAS), adipocyte fatty acid-binding protein (aP2), and lipoprotein lipase (LPL), were significantly down-regulated by treatment with GBR when compared to that of untreated control cells. Moreover, tumor necrosis factor-α (TNF-α) and interlukin-6 (IL-6) mRNA expressions were attenuated by GBR in mature adipocytes. These data suggest that GBR exhibits an anti-adipogenic effect through the suppression of adipogenesis in 3T3-L1 adipocytes.

  16. The WNT/β-catenin pathway is involved in the anti-adipogenic activity of cerebrosides from the sea cucumber Cucumaria frondosa.

    Science.gov (United States)

    Xu, Hui; Wang, Fei; Wang, Jingfeng; Xu, Jie; Wang, Yuming; Xue, Changhu

    2015-07-01

    Both adipocyte hypertrophy and hyperplasia lead to obesity. Here, we isolated cerebrosides from the sea cucumber Cucumaria frondosa (CFC) and examined its anti-adipogenic activity in vitro. CFC inhibited the lipid accumulation of 3T3-L1 cells and suppressed PPARγ and C/EBPα expressions, proving its anti-adipogenic activity. Furthermore, CFC suppressed lipogenesis in mature adipocytes. The WNT/β-catenin pathway acts as an anti-adipogenic factor. CFC enhanced β-catenin expression, promoted its nuclear translocation and up-regulated the expression of CCND1 and c-myc, two target genes of β-catenin. Moreover, after cells were treated with the β-catenin inhibitor 21H7, β-catenin nuclear translocation and transcription activity can be recovered by CFC. These findings suggested that CFC promoted the activation of the WNT/β-catenin pathway. Besides, CFC enhanced the expressions of Fz1, LRP5 and LRP6, while it had no effect on the expressions of Wnt10b and GSK3β. These findings indicated that CFC exhibits anti-adipogenic activity through enhancing the activation of the WNT/β-catenin pathway, which was mediated by FZ and LRPs. PMID:26091058

  17. Mannose-binding dietary lectins induce adipogenic differentiation of the marrow-derived mesenchymal cells via an active insulin-like signaling mechanism.

    Science.gov (United States)

    Bajaj, Manmohan; Hinge, Ashwini; Limaye, Lalita S; Gupta, Rajesh Kumar; Surolia, Avadhesha; Kale, Vaijayanti P

    2011-04-01

    We have recently demonstrated that the mannose-binding lectins, namely banana lectin (BL) and garlic lectin (GL), interacted with the insulin receptors on M210B4 cells--an established mesenchymal cell line of murine marrow origin--and initiate mitogen-activated protein kinase kinase (MEK)-dependent extracellular signal-regulated kinase (ERK) signaling in them. In this study, we show that this lectin-mediated active ERK signaling culminates into an adipogenic differentiation of these cells. Gene expression studies indicate that the effect takes place at the transcriptional level. Experiments carried out with pharmacological inhibitors show that MEK-dependent ERK and phosphatidylinositol 3-kinase-dependent AKT pathways are positive regulators of the lectin- and insulin-mediated adipogenic differentiation, while stress-activated kinase/c-jun N-terminal kinase pathway acts as a negative one. Since both lectins could efficiently substitute for insulin in the standard adipogenic induction medium, they may perhaps serve as molecular tools to study the mechanistic aspects of the adipogenic process that are independent of cell proliferation. Our study clearly demonstrates the ability of BL and GL to activate insulin-like signaling in the mesenchymal cells in vitro leading to their adipocytic differentiation. The dietary origin of these lectins underscores an urgent need to examine their in vivo effects on tissue homeostasis.

  18. Biochemical analysis and structure determination of bacterial acetyltransferases responsible for the biosynthesis of UDP-N,N'-diacetylbacillosamine.

    Science.gov (United States)

    Morrison, Michael J; Imperiali, Barbara

    2013-11-01

    UDP-N,N'-diacetylbacillosamine (UDP-diNAcBac) is a unique carbohydrate produced by a number of bacterial species and has been implicated in pathogenesis. The terminal step in the formation of this important bacterial sugar is catalyzed by an acetyl-CoA (AcCoA)-dependent acetyltransferase in both N- and O-linked protein glycosylation pathways. This bacterial acetyltransferase is a member of the left-handed β-helix family and forms a homotrimer as the functional unit. Whereas previous endeavors have focused on the Campylobacter jejuni acetyltransferase (PglD) from the N-linked glycosylation pathway, structural characterization of the homologous enzymes in the O-linked glycosylation pathways is lacking. Herein, we present the apo-crystal structures of the acetyltransferase domain (ATD) from the bifunctional enzyme PglB (Neisseria gonorrhoeae) and the full-length acetyltransferase WeeI (Acinetobacter baumannii). Additionally, a PglB-ATD structure was solved in complex with AcCoA. Surprisingly, this structure reveals a contrasting binding mechanism for this substrate when compared with the AcCoA-bound PglD structure. A comparison between these findings and the previously solved PglD crystal structures illustrates a dichotomy among N- and O-linked glycosylation pathway enzymes. Based upon these structures, key residues in the UDP-4-amino and AcCoA binding pockets were mutated to determine their effect on binding and catalysis in PglD, PglB-ATD, and WeeI. Last, a phylogenetic analysis of the aforementioned acetyltransferases was employed to illuminate the diversity among N- and O-linked glycosylation pathway enzymes. PMID:24064219

  19. A novel regulatory function of sweet taste-sensing receptor in adipogenic differentiation of 3T3-L1 cells.

    Directory of Open Access Journals (Sweden)

    Yosuke Masubuchi

    Full Text Available BACKGROUND: Sweet taste receptor is expressed not only in taste buds but also in nongustatory organs such as enteroendocrine cells and pancreatic beta-cells, and may play more extensive physiological roles in energy metabolism. Here we examined the expression and function of the sweet taste receptor in 3T3-L1 cells. METHODOLOGY/PRINCIPAL FINDINGS: In undifferentiated preadipocytes, both T1R2 and T1R3 were expressed very weakly, whereas the expression of T1R3 but not T1R2 was markedly up-regulated upon induction of differentiation (by 83.0 and 3.8-fold, respectively at Day 6. The α subunits of Gs (Gαs and G14 (Gα14 but not gustducin were expressed throughout the differentiation process. The addition of sucralose or saccharin during the first 48 hours of differentiation considerably reduced the expression of peroxisome proliferator activated receptor γ (PPARγ and CCAAT/enhancer-binding protein α (C/EBPα at Day 2, the expression of aP2 at Day 4 and triglyceride accumulation at Day 6. These anti-adipogenic effects were attenuated by short hairpin RNA-mediated gene-silencing of T1R3. In addition, overexpression of the dominant-negative mutant of Gαs but not YM-254890, an inhibitor of Gα14, impeded the effects of sweeteners, suggesting a possible coupling of Gs with the putative sweet taste-sensing receptor. In agreement, sucralose and saccharin increased the cyclic AMP concentration in differentiating 3T3-L1 cells and also in HEK293 cells heterologously expressing T1R3. Furthermore, the anti-adipogenic effects of sweeteners were mimicked by Gs activation with cholera toxin but not by adenylate cyclase activation with forskolin, whereas small interfering RNA-mediated knockdown of Gαs had the opposite effects. CONCLUSIONS: 3T3-L1 cells express a functional sweet taste-sensing receptor presumably as a T1R3 homomer, which mediates the anti-adipogenic signal by a Gs-dependent but cAMP-independent mechanism.

  20. REDUCED GLUTEAL EXPRESSION OF ADIPOGENIC AND LIPOGENIC GENES IN BLACK SOUTH AFRICAN WOMEN IS ASSOCIATED WITH OBESITY-RELATED INSULIN RESISTANCE

    Science.gov (United States)

    Goedecke, Julia H.; Evans, Juliet; Keswell, Dheshnie; Stimson, Roland H.; Livingstone, Dawn E.W.; Hayes, Philip; Adams, Kevin; Dave, Joel A.; Victor, Hendriena; Levitt, Naomi S.; Lambert, Estelle V.; Walker, Brian R.; Seckl, Jonathan R.; Olsson, Tommy; Kahn, Steven E.

    2014-01-01

    Context Black South African women are less insulin sensitive than their white counterparts, despite less central and greater peripheral fat deposition. We hypothesized that this paradox may be explained, in part, by differences in the adipogenic capacity of subcutaneous adipose tissue (SAT). Objective To measure adipogenic and lipogenic gene expression in abdominal and gluteal SAT depots, and determine their relationships with insulin sensitivity (SI) in South African women. Design Cross-sectional. Participants 14 normal-weight (BMI 30 kg/m2) black and 13 obese white premenopausal South African women. Main outcomes SI (frequently sampled intravenous glucose tolerance test) in relation to expression of adipogenic and lipogenic genes in abdominal and gluteal SAT depots. Results With increasing BMI, black women had less visceral fat (P=0.03) and more abdominal (P=0.017) and gynoid (P=0.041) SAT but had lower SI (P<0.01) than white women. The expression of adipogenic and lipogenic genes was proportionately lower with obesity in black, but not white women in the gluteal and deep SAT depots (P<0.05 for ethnicity x BMI effect). In black women only, the expression of these genes correlated positively with SI (all P<0.05), independently of age and fat mass. Conclusions Obese black women have reduced SAT expression of adipogenic and lipogenic genes compared to white women, which associates with reduced SI. These findings suggest that obesity in black women impairs SAT adipogenesis and storage, potentially leading to insulin resistance and increased risk of type 2 diabetes. PMID:21956425

  1. Immunolocalization of choline acetyltransferase of common type in the central brain mass of Octopus vulgaris

    Directory of Open Access Journals (Sweden)

    A. Casini

    2012-07-01

    Full Text Available Acetylcholine, the first neurotransmitter to be identified in the vertebrate frog, is widely distributed among the animal kingdom. The presence of a large amount of acetylcholine in the nervous system of cephalopods is well known from several biochemical and physiological studies. However, little is known about the precise distribution of cholinergic structures due to a lack of a suitable histochemical technique for detecting acetylcholine. The most reliable method to visualize the cholinergic neurons is the immunohistochemical localization of the enzyme choline acetyltransferase, the synthetic enzyme of acetylcholine. Following our previous study on the distribution patterns of cholinergic neurons in the Octopus vulgaris visual system, using a novel antibody that recognizes choline acetyltransferase of the common type (cChAT, now we extend our investigation on the octopus central brain mass. When applied on sections of octopus central ganglia, immunoreactivity for cChAT was detected in cell bodies of all central brain mass lobes with the notable exception of the subfrontal and subvertical lobes. Positive varicosed nerves fibers where observed in the neuropil of all central brain mass lobes.

  2. Immunolocalization of choline acetyltransferase of common type in the central brain mass of Octopus vulgaris.

    Science.gov (United States)

    Casini, A; Vaccaro, R; D'Este, L; Sakaue, Y; Bellier, J P; Kimura, H; Renda, T G

    2012-07-19

    Acetylcholine, the first neurotransmitter to be identified in the vertebrate frog, is widely distributed among the animal kingdom. The presence of a large amount of acetylcholine in the nervous system of cephalopods is well known from several biochemical and physiological studies. However, little is known about the precise distribution of cholinergic structures due to a lack of a suitable histochemical technique for detecting acetylcholine. The most reliable method to visualize the cholinergic neurons is the immunohistochemical localization of the enzyme choline acetyltransferase, the synthetic enzyme of acetylcholine. Following our previous study on the distribution patterns of cholinergic neurons in the Octopus vulgaris visual system, using a novel antibody that recognizes choline acetyltransferase of the common type (cChAT), now we extend our investigation on the octopus central brain mass. When applied on sections of octopus central ganglia, immunoreactivity for cChAT was detected in cell bodies of all central brain mass lobes with the notable exception of the subfrontal and subvertical lobes. Positive varicosed nerves fibers where observed in the neuropil of all central brain mass lobes.

  3. The Protein Acetyltransferase PatZ from Escherichia coli Is Regulated by Autoacetylation-induced Oligomerization.

    Science.gov (United States)

    de Diego Puente, Teresa; Gallego-Jara, Julia; Castaño-Cerezo, Sara; Bernal Sánchez, Vicente; Fernández Espín, Vanesa; García de la Torre, José; Manjón Rubio, Arturo; Cánovas Díaz, Manuel

    2015-09-18

    Lysine acetylation is an important post-translational modification in the metabolic regulation of both prokaryotes and eukaryotes. In Escherichia coli, PatZ (formerly YfiQ) is the only known acetyltransferase protein and is responsible for acetyl-CoA synthetase acetylation. In this study, we demonstrated PatZ-positive cooperativity in response to acetyl-CoA and the regulation of acetyl-CoA synthetase activity by the acetylation level. Furthermore, functional analysis of an E809A mutant showed that the conserved glutamate residue is not relevant for the PatZ catalytic mechanism. Biophysical studies demonstrated that PatZ is a stable tetramer in solution and is transformed to its octameric form by autoacetylation. Moreover, this modification is reversed by the sirtuin CobB. Finally, an in silico PatZ tetramerization model based on hydrophobic and electrostatic interactions is proposed and validated by three-dimensional hydrodynamic analysis. These data reveal, for the first time, the structural regulation of an acetyltransferase by autoacetylation in a prokaryotic organism.

  4. Diurnal cycles in serotonin acetyltransferase activity and cyclic GMP content of cultured chick pineal glands.

    Science.gov (United States)

    Wainwright, S D

    1980-06-12

    Levels of serotonin N-acetyltransferase (NAT: acetul CoA:arylamine N-acetyltransferase; EC 2.1.1.5.) activity in the chick pineal gland exhibit a marked diurnal variation in birds kept under a diurnal cycle of ilumination. Activity begins to rise rapidly at the start of the dark phase of the cycle and reaches maximum levels at mid-dark phase about 25-fold greater than the minimum basal level at mid-light phase. Thereafter, the level of activity declines to the basal level about the start of the light phase. This diurnal cycle in chick pineal NAT activity found in vivo has recently been reproduced in vitro with intact glands incubated in organ culture. The mechanism of the 'biological clock' which regulates these variations in level of chick pineal NAT activity is unknown. However, I now report that chick pineal glands cultured under a diurnal cycle of illumination exhibit a diurnal cycle in content of cyclic GMP which roughly parallels the cycles in NAT activity. In contrast, there was no correlation between variations in pineal content of cyclic AMP and in level of NAT activity. PMID:6250035

  5. Different anti-adipogenic effects of bio-compounds on primary visceral pre-adipocytes and adipocytes.

    Science.gov (United States)

    Colitti, Monica; Stefanon, Bruno

    2016-01-01

    Several natural compounds exhibit strong capacity for decreasing triglyceride accumulation, enhancing lipolysis and inducing apoptosis. The present study reports the anti-adipogenic effects of Silybum marianum (SL), Citrus aurantium (CA), Taraxacum officinale (TO), resveratrol (RE), Curcuma longa (CU), caffeine (CF), oleuropein (OL) and docosahexaenoic acid (DHA) in reducing differentiation and increasing lipolysis and apoptosis. Analyses were performed on human primary visceral pre-adipocytes after 10 (P10) and 20 (P20) days of treatment during differentiation and on mature adipocytes after 7 days of treatment (A7). The percentage of apoptosis induced by TO extract in P10 and P20 cells was significantly higher than that induced by all other compounds and in CTRL cells. Triglyceride accumulation was significantly lower in cells treated with DHA, CF, RE in comparison to cells treated with OL and in CTRL cells. Treatments with CF, DHA and OL significantly incremented lipolysis in P20 cells in comparison to other compounds and in CTRL cells. On the contrary, the treatment of A7 cells with OL, CA and TO compounds significantly increased cell lipolysis. The addition of CF in differentiating P20 pre-adipocytes significantly increased the expression of genes involved in inhibition of adipogenesis, such as GATA2, GATA3, WNT1, WNT3A, SFRP5, and DLK1. Genes involved in promoting adipogenesis such as CCND1, CEBPB and SREBF1 were significantly down-regulated by the treatment. The screening of bioactive compounds for anti-adipogenic effects showed that in differentiating cells TO extract was the most effective in inducing apoptosis and CF and DHA extracts were more efficient in inhibition of differentiation and in induction of cell lipolysis. PMID:27540349

  6. The Expression of Adipogenic Genes in Adipose Tissues of Feedlot Steers Fed Supplementary Palm Oil or Soybean Oil.

    Science.gov (United States)

    Choi, Seong Ho; Park, Sung Kwon; Choi, Chang Weon; Li, Xiang Zi; Kim, Kyoung Hoon; Kim, Won Young; Jeong, Joon; Johnson, Bradley J; Zan, Linsen; Smith, Stephen B

    2016-03-01

    We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD) gene expression in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control), with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and α-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha (AMPKα) and peroxisome proliferator-activated receptor gamma (PPARγ) increased between the initial and intermediate biopsies and declined thereafter (padipose tissue than in s.c. adipose tissue (padipose tissue of palm oil-fed steers than in control steers (p = 0.04) and CCAAT enhancer binding protein-beta (CEBPβ) gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (padipose tissue (p = 0.05); SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers. Contrary to our original hypothesis, palm oil did not promote adipogenic gene expression in s.c. and i.m. adipose tissue.

  7. Spot14/Spot14R expression may be involved in MSC adipogenic differentiation in patients with adolescent idiopathic scoliosis

    Science.gov (United States)

    WANG, QIFEI; YANG, JUNLIN; LIN, XIANG; HUANG, ZIFANG; XIE, CHAOFAN; FAN, HENGWEI

    2016-01-01

    The aim of the present study was to evaluate the different expression levels of thyroid hormone responsive (THRSP; Spot14)/S14 related, Mig12 (S14R) during bone marrow mesenchymal stem cell (BM-MSC) adipogenesis in adolescent idiopathic scoliosis (AIS) patients. MSCs were retrospectively isolated from AIS patients and controls, and adipogenic differentiation was induced. Total RNA was extracted for Affymetrix 3′-IVT expression profiling microarrays and compared with the results from healthy controls. The results were confirmed by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) validation and the protein expression levels of Spot14 and its paralogous gene S14R by western blotting and immunohistochemistry. A total of 300 significantly altered mRNAs were detected (111 upregulated and 189 downregulated) and confirmed by RT-qPCR. The mRNA expression levels of seven genes, including Spot14, were altered by >2-fold in AIS patients. Spot14/S14R was selected for further investigation. The results of the western blotting demonstrated that mRNA and protein expression levels of Spot14/S14R were significantly higher in AIS patients than the controls (P<0.05). Immunohistochemistry demonstrated Spot14 was expressed in 85% (17/20 cases) in adipose tissue samples from AIS patients and 23.1% (3/13 cases) of adipose tissue samples from controls. The positive ratio of Spot14 in adipose tissue samples from AIS was significantly higher than the controls (P<0.001). The results of the present study indicated that Spot14/S14R were differently expressed in MSC adipogenesis in AIS patients, and they may be important in the abnormal adipogenic differentiation in AIS. PMID:27082501

  8. Dissociable roles for histone acetyltransferases p300 and PCAF in hippocampus and perirhinal cortex-mediated object memory.

    Science.gov (United States)

    Mitchnick, K A; Creighton, S D; Cloke, J M; Wolter, M; Zaika, O; Christen, B; Van Tiggelen, M; Kalisch, B E; Winters, B D

    2016-07-01

    The importance of histone acetylation for certain types of memory is now well established. However, the specific contributions of the various histone acetyltransferases to distinct memory functions remain to be determined; therefore, we employed selective histone acetyltransferase protein inhibitors and short-interference RNAs to evaluate the roles of CREB-binding protein (CBP), E1A-binding protein (p300) and p300/CBP-associated factor (PCAF) in hippocampus and perirhinal cortex (PRh)-mediated object memory. Rats were tested for short- (STM) and long-term memory (LTM) in the object-in-place task, which relies on the hippocampus and PRh for spatial memory and object identity processing, respectively. Selective inhibition of these histone acetyltransferases by small-interfering RNA and pharmacological inhibitors targeting the HAT domain produced dissociable effects. In the hippocampus, CBP or p300 inhibition impaired long-term but not short-term object memory, while inhibition of PCAF impaired memory at both delays. In PRh, HAT inhibition did not impair STM, and only CBP and PCAF inhibition disrupted LTM; p300 inhibition had no effects. Messenger RNA analyses revealed findings consistent with the pattern of behavioral effects, as all three enzymes were upregulated in the hippocampus (dentate gyrus) following learning, whereas only CBP and PCAF were upregulated in PRh. These results demonstrate, for the first time, the necessity of histone acetyltransferase activity for PRh-mediated object memory and indicate that the specific mnemonic roles of distinctive histone acetyltransferases can be dissociated according to specific brain regions and memory timeframe. PMID:27251651

  9. Association with the origin recognition complex suggests a novel role for histone acetyltransferase Hat1p/Hat2p

    Directory of Open Access Journals (Sweden)

    Greenblatt Jack F

    2007-09-01

    Full Text Available Abstract Background Histone modifications have been implicated in the regulation of transcription and, more recently, in DNA replication and repair. In yeast, a major conserved histone acetyltransferase, Hat1p, preferentially acetylates lysine residues 5 and 12 on histone H4. Results Here, we report that a nuclear sub-complex consisting of Hat1p and its partner Hat2p interacts physically and functionally with the origin recognition complex (ORC. While mutational inactivation of the histone acetyltransferase (HAT gene HAT1 alone does not compromise origin firing or initiation of DNA replication, a deletion in HAT1 (or HAT2 exacerbates the growth defects of conditional orc-ts mutants. Thus, the ORC-associated Hat1p-dependent histone acetyltransferase activity suggests a novel linkage between histone modification and DNA replication. Additional genetic and biochemical evidence points to the existence of partly overlapping histone H3 acetyltransferase activities in addition to Hat1p/Hat2p for proper DNA replication efficiency. Furthermore, we demonstrated a dynamic association of Hat1p with chromatin during S-phase that suggests a role of this enzyme at the replication fork. Conclusion We have found an intriguing new association of the Hat1p-dependent histone acetyltransferase in addition to its previously known role in nuclear chromatin assembly (Hat1p/Hat2p-Hif1p. The participation of a distinct Hat1p/Hat2p sub-complex suggests a linkage of histone H4 modification with ORC-dependent DNA replication.

  10. Dorsal root ganglion progenitors differentiate to gamma-aminobutyric acid- and choline acetyltransferase-positive neurons

    Institute of Scientific and Technical Information of China (English)

    Lingli Yu; Yindi Ding; Ambre Spencer; Ji Ma; Ruisheng Lu; Brian B. Rudkin; Chonggang Yuan

    2012-01-01

    This study examined the isolation and differentiation of dorsal root ganglion progenitor cells for therapeutic use in neurodegenerative diseases.Rat embryonic dorsal root ganglia progenitors were isolated and purified using the differential adhesion method combined with cytosine arabinoside treatment.After culture in serum-free medium supplemented with B27, basic fibroblast growth factor and epidermal growth factor, these cells remained viable and survived for more than 18 months in vitro.Most cells differentiated to neurons that were immunoreactive for gamma-aminobutyric acid and choline acetyltransferase as detected by immunohistochemical staining.In addition, nerve growth factor and neurotrophic tyrosine kinase receptor expression were also observed in dorsal root ganglion progenitors and differentiated cells.K252a, an inhibitor that blocks nerve growth factor-induced signaling, inhibited cell survival, suggesting the possible existence of a nerve growth factor autocrine loop in these proliferating cells.

  11. Integration of Bioorthogonal Probes and Q-FRET for the Detection of Histone Acetyltransferase Activity.

    Science.gov (United States)

    Han, Zhen; Luan, Yepeng; Zheng, Yujun George

    2015-12-01

    Histone acetyltransferases (HATs) are key players in the epigenetic regulation of gene function. The recent discovery of diverse HAT substrates implies a broad spectrum of cellular functions of HATs. Many pathological processes are also intimately associated with the dysregulation of HAT levels and activities. However, detecting the enzymatic activity of HATs has been challenging, and this has significantly impeded drug discovery. To advance the field, we developed a convenient one-pot, mix-and-read strategy that is capable of directly detecting the acylated histone product through a fluorescent readout. The strategy integrates three technological platforms-bioorthogonal HAT substrate labeling, alkyne-azide click chemistry, and quenching FRET-into one system for effective probing of HAT enzyme activity. PMID:26455821

  12. Characterization of two metagenome-derived esterases that reactivate chloramphenicol by counteracting chloramphenicol acetyltransferase.

    Science.gov (United States)

    Tao, Weixin; Lee, Myung Hwan; Yoon, Mi-Young; Kim, Jin-Cheol; Malhotra, Shweta; Wu, Jing; Hwang, Eul Chul; Lee, Seon-Woo

    2011-12-01

    Function-driven metagenomic analysis is a powerful approach to screening for novel biocatalysts. In this study, we investigated lipolytic enzymes selected from an alluvial soil metagenomic library, and identified two novel esterases, EstDL26 and EstDL136. EstDL26 and EstDL136 reactivated chloramphenicol from its acetyl derivates by counteracting the chloramphenicol acetyltransferase (CAT) activity in Escherichia coli. These two enzymes showed only 27% identity in amino acid sequence to each other; however both preferentially hydrolyzed short-chain p-nitrophenyl esters (lipase (HSL), and since chloramphenicol acetate esterase (CAE) activity was detected from two other soil esterases in the HSL family, this suggests a distribution of CAE among the soil microorganisms. The isolation and characterization of EstDL26 and EstDL136 in this study may be helpful in understanding the diversity of CAE enzymes and their potential role in releasing active chloramphenicol in the producing bacteria. PMID:22210605

  13. Interferon-Induced Spermidine-Spermine Acetyltransferase and Polyamine Depletion Restrict Zika and Chikungunya Viruses.

    Science.gov (United States)

    Mounce, Bryan C; Poirier, Enzo Z; Passoni, Gabriella; Simon-Loriere, Etienne; Cesaro, Teresa; Prot, Matthieu; Stapleford, Kenneth A; Moratorio, Gonzalo; Sakuntabhai, Anavaj; Levraud, Jean-Pierre; Vignuzzi, Marco

    2016-08-10

    Polyamines are small, positively charged molecules derived from ornithine and synthesized through an intricately regulated enzymatic pathway. Within cells, they are abundant and play several roles in diverse processes. We find that polyamines are required for the life cycle of the RNA viruses chikungunya virus (CHIKV) and Zika virus (ZIKV). Depletion of spermidine and spermine via type I interferon signaling-mediated induction of spermidine/spermine N1-acetyltransferase (SAT1), a key catabolic enzyme in the polyamine pathway, restricts CHIKV and ZIKV replication. Polyamine depletion restricts these viruses in vitro and in vivo, due to impairment of viral translation and RNA replication. The restriction is released by exogenous replenishment of polyamines, further supporting a role for these molecules in virus replication. Thus, SAT1 and, more broadly, polyamine depletion restrict viral replication and suggest promising avenues for antiviral therapies. PMID:27427208

  14. Cigarette Smoking, N-Acetyltransferase 2 Acetylation Status, and Bladder Cancer Risk

    DEFF Research Database (Denmark)

    Marcus, P.M.; Hayes, R.B.; Vineis, P.;

    2000-01-01

    Tobacco use is an established cause of bladder cancer. The ability to detoxify aromatic amines, which are present in tobacco and are potent bladder carcinogens, is compromised in persons with the N-acetyltransferase 2 slow acetylation polymorphism. The relationship of cigarette smoking with bladder...... cancer risk therefore has been hypothesized to be stronger among slow acetylators. The few studies to formally explore such a possibility have produced inconsistent results, however. To assess this potential gene-environment interaction in as many bladder cancer studies as possible and to summarize...... results, we conducted a meta-analysis using data from 16 bladder cancer studies conducted in the general population (n = 1999 cases), Most had been conducted in European countries. Because control subjects were unavailable for a number of these studies, we used a case-series design, which can be used...

  15. Density Functional Theory Study on the Histidine-assisted Mechanism of Arylamine N-Acetyltransferase Acetylation

    Institute of Scientific and Technical Information of China (English)

    QIAO Qing-An; GAO Shan-Min; JIN Yue-Qing; CHEN Xin; SUN Xiao-Min; YANG Chuan-Lu

    2008-01-01

    Arylamine N-acetyltransferases (NATs, EC 2.3.1.5) catalyze the N-acetylation of primary arylamines, and play a key role in the biotransformation and metabolism of drugs, carcinogens, etc.In this paper, three possible reaction mechanisms are investigated and the results indicate that if the acetyl group directly transfers from the donor to the acceptor, the high activation energies will make it hard to obtain the target products.When using histidine to mediate the acetylation process, these energies will drop in the 15~45 kJ/mol range.If the histidine residue is protonated, the corresponding energies will be decreased by about 35~87 kJ/mol.The calculations predict an enzymatic acetylation mechanism that undergoes a thiolate-imidazolium pair, which agrees with the experimental results very well.

  16. Epigenetic change in kidney tumor: downregulation of histone acetyltransferase MYST1 in human renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Wang Yong

    2013-02-01

    Full Text Available Abstract Background MYST1 (also known as hMOF, a member of the MYST family of histone acetyltransferases (HATs as an epigenetic mark of active genes, is mainly responsible for histone H4K16 acetylation in the cells. Recent studies have shown that the abnormal gene expression of hMOF is involved in certain primary cancers. Here we examined the involvement of hMOF expression and histone H4K16 acetylation in primary renal cell carcinoma (RCC. Simultaneously, we investigated the correlation between the expression of hMOF and clear cell RCC (ccRCC biomarker carbohydrase IX (CA9 in RCC. Materials and methods The frozen RCC tissues and RCC cell lines as materials, the reverse transcription polymerase chain reaction (RT-PCR, western blotting and immunohistochemical staining approaches were used. Results RT-PCR results indicate that hMOF gene expression levels frequently downregulated in 90.5% of patients (19/21 with RCC. The reduction of hMOF protein in both RCC tissues and RCC cell lines is tightly correlated with acetylation of histone H4K16. In addition, overexpression of CA9 was detected in 100% of ccRCC patients (21/21. However, transient transfection of hMOF in ccRCC 786–0 cells did not affect both the gene and protein expression of CA9. Conclusion hMOF as an acetyltransferase of H4K16 might be involved in the pathogenesis of kidney cancer, and this epigenetic changes might be a new CA9-independent RCC diagnostic maker.

  17. The SAGA histone acetyltransferase complex regulates leucine uptake through the Agp3 permease in fission yeast.

    Science.gov (United States)

    Takahashi, Hidekazu; Sun, Xiaoying; Hamamoto, Makiko; Yashiroda, Yoko; Yoshida, Minoru

    2012-11-01

    Metabolic responses of unicellular organisms are mostly acute, transient, and cell-autonomous. Regulation of nutrient uptake in yeast is one such rapid response. High quality nitrogen sources such as NH(4)(+) inhibit uptake of poor nitrogen sources, such as amino acids. Both transcriptional and posttranscriptional mechanisms operate in nutrient uptake regulation; however, many components of this system remain uncharacterized in the fission yeast, Schizosaccharomyces pombe. Here, we demonstrate that the Spt-Ada-Gcn acetyltransferase (SAGA) complex modulates leucine uptake. Initially, we noticed that a branched-chain amino acid auxotroph exhibits a peculiar adaptive growth phenotype on solid minimal media containing certain nitrogen sources. In fact, the growth of many auxotrophic strains is inhibited by excess NH(4)Cl, possibly through nitrogen-mediated uptake inhibition of the corresponding nutrients. Surprisingly, DNA microarray analysis revealed that the transcriptional reprogramming during the adaptation of the branched-chain amino acid auxotroph was highly correlated with reprogramming observed in deletions of the SAGA histone acetyltransferase module genes. Deletion of gcn5(+) increased leucine uptake in the prototrophic background and rendered the leucine auxotroph resistant to NH(4)Cl. Deletion of tra1(+) caused the opposite phenotypes. The increase in leucine uptake in the gcn5Δ mutant was dependent on an amino acid permease gene, SPCC965.11c(+). The closest budding yeast homolog of this permease is a relatively nonspecific amino acid permease AGP3, which functions in poor nutrient conditions. Our analysis identified the regulation of nutrient uptake as a physiological function for the SAGA complex, providing a potential link between cellular metabolism and chromatin regulation.

  18. Function and subcellular localization of Gcn5, a histone acetyltransferase in Candida albicans.

    Science.gov (United States)

    Chang, Peng; Fan, Xueyi; Chen, Jiangye

    2015-08-01

    Candida albicans is an opportunistic fungal pathogen commonly found in humans. It has the ability to switch reversibly between three growth forms: budding yeast, pseudohypha, and hypha. The transition between yeast and hyphal growth forms is critical for the pathogenesis of C. albicans. During the yeast-to-hypha morphologic transition, gene expression is regulated by transcriptional regulators including histone modifying complexes and chromatin remodeling complexes. We previously reported that Esa1, a catalytic subunit in the histone acetyltransferase complex NuA4, is essential for the hyphal development of C. albicans. In this study, we analyzed the functional roles of Gcn5, a catalytic subunit in the histone acetyltransferase complex SAGA, in C. albicans. Gcn5 is required for the invasive and filamentous growth of C. albicans. Deletion of GCN5 impaired hyphal elongation in sensing serum and attenuated the virulence of C. albicans in a mouse systemic infection model. The C. albicans gcn5/gcn5 mutant cells also exhibited sensitivity to cell wall stress. Functional analysis showed that the HAT domain and Bromodomain in Gcn5 play distinct roles in morphogenesis and cell wall stress response of C. albicans. Our results show that the conserved residue Glu188 is crucial for the Gcn5 HAT activity and for Gcn5 function during filamentous growth. In addition, the subcellular distribution of ectopically expressed GFP-Gcn5 correlates with the different growth states of C. albicans. In stationary phase, Gcn5 accumulated in the nucleus, while during vegetative growth it localized in the cytoplasm in a morpha-independent manner. Our results suggest that the nuclear localization of Gcn5 depends on the existence of its N-terminal NLS and HAT domains.

  19. Sulphoacetaldehyde acetyltransferase yields acetyl phosphate: purification from Alcaligenes defragrans and gene clusters in taurine degradation.

    Science.gov (United States)

    Ruff, Jürgen; Denger, Karin; Cook, Alasdair M

    2003-01-15

    The facultatively anaerobic bacterium Alcaligenes defragrans NKNTAU was found to oxidize taurine (2-aminoethanesulphonate) with nitrate as the terminal electron acceptor. Taurine was transaminated to 2-sulphoacetaldehyde. This was not converted into sulphite and acetate by a "sulphoacetaldehyde sulpho-lyase" (EC 4.4.1.12), but into sulphite and acetyl phosphate, which was identified by three methods. The enzyme, which required the addition of phosphate, thiamin diphosphate and Mg(2+) ions for activity, was renamed sulphoacetaldehyde acetyltransferase (Xsc; EC 2.3.1.-). Inducible Xsc was expressed at high levels, and a three-step 11-fold purification yielded an essentially homogeneous soluble protein, which was a homotetramer in its native form; the molecular mass of the subunit was found to be between about 63 kDa (SDS/PAGE) and 65.3 kDa (matrix-assisted laser-desorption ionization-time-of-flight MS). The N-terminal and two internal amino acid sequences were determined, and PCR primers were generated. The xsc gene was amplified and sequenced; the derived molecular mass of the processed protein was 65.0 kDa. The downstream gene presumably encoded the inducible phosphate acetyltransferase (Pta) found in crude extracts. The desulphonative enzymes ("EC 4.4.1.12") from Achromobacter xylosoxidans NCIMB 10751 and Desulfonispora thiosulfatigenes GKNTAU were shown to be Xscs. We detected at least three subclasses of xsc in Proteobacteria and in Gram-positive bacteria, and they comprised a distinct group within the acetohydroxyacid synthase supergene family. Genome sequencing data revealed xsc genes in Burkholderia fungorum (80% sequence identity) and Sinorhizobium meliloti (61%) with closely linked pta genes. Different patterns of regulation for the transport and dissimilation of taurine were hypothesized for S. meliloti and B. fungorum. PMID:12358600

  20. Histone acetyltransferase inhibitor CPTH6 preferentially targets lung cancer stem-like cells.

    Science.gov (United States)

    Di Martile, Marta; Desideri, Marianna; De Luca, Teresa; Gabellini, Chiara; Buglioni, Simonetta; Eramo, Adriana; Sette, Giovanni; Milella, Michele; Rotili, Dante; Mai, Antonello; Carradori, Simone; Secci, Daniela; De Maria, Ruggero; Del Bufalo, Donatella; Trisciuoglio, Daniela

    2016-03-01

    Cancer stem cells (CSCs) play an important role in tumor initiation, progression, therapeutic failure and tumor relapse. In this study, we evaluated the efficacy of the thiazole derivative 3-methylcyclopentylidene-[4-(4'-chlorophenyl)thiazol-2-yl]hydrazone (CPTH6), a novel pCAF and Gcn5 histone acetyltransferase inhibitor, as a small molecule that preferentially targets lung cancer stem-like cells (LCSCs) derived from non-small cell lung cancer (NSCLC) patients. Notably, although CPTH6 inhibits the growth of both LCSC and NSCLC cell lines, LCSCs exhibit greater growth inhibition than established NSCLC cells. Growth inhibitory effect of CPTH6 in LCSC lines is primarily due to apoptosis induction. Of note, differentiated progeny of LCSC lines is more resistant to CPTH6 in terms of loss of cell viability and reduction of protein acetylation, when compared to their undifferentiated counterparts. Interestingly, in LCSC lines CPTH6 treatment is also associated with a reduction of stemness markers. By using different HAT inhibitors we provide clear evidence that inhibition of HAT confers a strong preferential inhibitory effect on cell viability of undifferentiated LCSC lines when compared to their differentiated progeny. In vivo, CPTH6 is able to inhibit the growth of LCSC-derived xenografts and to reduce cancer stem cell content in treated tumors, as evidenced by marked reduction of tumor-initiating capacity in limiting dilution assays. Strikingly, the ability of CPTH6 to inhibit tubulin acetylation is also confirmed in vivo. Overall, our studies propose histone acetyltransferase inhibition as an attractive target for cancer therapy of NSCLC. PMID:26870991

  1. Histone acetyltransferase inhibitor CPTH6 preferentially targets lung cancer stem-like cells

    Science.gov (United States)

    Di Martile, Marta; Desideri, Marianna; De Luca, Teresa; Gabellini, Chiara; Buglioni, Simonetta; Eramo, Adriana; Sette, Giovanni; Milella, Michele; Rotili, Dante; Mai, Antonello; Carradori, Simone; Secci, Daniela; De Maria, Ruggero; Del Bufalo, Donatella; Trisciuoglio, Daniela

    2016-01-01

    Cancer stem cells (CSCs) play an important role in tumor initiation, progression, therapeutic failure and tumor relapse. In this study, we evaluated the efficacy of the thiazole derivative 3-methylcyclopentylidene-[4-(4′-chlorophenyl)thiazol-2-yl]hydrazone (CPTH6), a novel pCAF and Gcn5 histone acetyltransferase inhibitor, as a small molecule that preferentially targets lung cancer stem-like cells (LCSCs) derived from non-small cell lung cancer (NSCLC) patients. Notably, although CPTH6 inhibits the growth of both LCSC and NSCLC cell lines, LCSCs exhibit greater growth inhibition than established NSCLC cells. Growth inhibitory effect of CPTH6 in LCSC lines is primarily due to apoptosis induction. Of note, differentiated progeny of LCSC lines is more resistant to CPTH6 in terms of loss of cell viability and reduction of protein acetylation, when compared to their undifferentiated counterparts. Interestingly, in LCSC lines CPTH6 treatment is also associated with a reduction of stemness markers. By using different HAT inhibitors we provide clear evidence that inhibition of HAT confers a strong preferential inhibitory effect on cell viability of undifferentiated LCSC lines when compared to their differentiated progeny. In vivo, CPTH6 is able to inhibit the growth of LCSC-derived xenografts and to reduce cancer stem cell content in treated tumors, as evidenced by marked reduction of tumor-initiating capacity in limiting dilution assays. Strikingly, the ability of CPTH6 to inhibit tubulin acetylation is also confirmed in vivo. Overall, our studies propose histone acetyltransferase inhibition as an attractive target for cancer therapy of NSCLC. PMID:26870991

  2. Structural and functional characterization of TRI3 trichothecene 15-O-acetyltransferase from Fusarium sporotrichioides

    Energy Technology Data Exchange (ETDEWEB)

    Garvey, Graeme S.; McCormick, Susan P.; Alexander, Nancy J.; Rayment, Ivan; (US-Agriculture); (UW)

    2009-08-14

    Fusarium head blight is a devastating disease of cereal crops whose worldwide incidence is increasing and at present there is no satisfactory way of combating this pathogen or its associated toxins. There is a wide variety of trichothecene mycotoxins and they all contain a 12,13-epoxytrichothecene skeleton but differ in their substitutions. Indeed, there is considerable variation in the toxin profile across the numerous Fusarium species that has been ascribed to differences in the presence or absence of biosynthetic enzymes and their relative activity. This article addresses the source of differences in acetylation at the C15 position of the trichothecene molecule. Here, we present the in vitro structural and biochemical characterization of TRI3, a 15-O-trichothecene acetyltransferase isolated from F. sporotrichioides and the 'in vivo' characterization of Deltatri3 mutants of deoxynivalenol (DON) producing F. graminearum strains. A kinetic analysis shows that TRI3 is an efficient enzyme with the native substrate, 15-decalonectrin, but is inactive with either DON or nivalenol. The structure of TRI3 complexed with 15-decalonectrin provides an explanation for this specificity and shows that Tri3 and Tri101 (3-O-trichothecene acetyltransferase) are evolutionarily related. The active site residues are conserved across all sequences for TRI3 orthologs, suggesting that differences in acetylation at C15 are not due to differences in Tri3. The tri3 deletion mutant shows that acetylation at C15 is required for DON biosynthesis even though DON lacks a C15 acetyl group. The enzyme(s) responsible for deacetylation at the 15 position of the trichothecene mycotoxins have not been identified.

  3. Anti-adipogenic effect of epiberberine is mediated by regulation of the Raf/MEK1/2/ERK1/2 and AMPKα/Akt pathways.

    Science.gov (United States)

    Choi, Jae Sue; Kim, Ji-Hye; Ali, Md Yousof; Jung, Hee Jin; Min, Byung-Sun; Choi, Ran Joo; Kim, Gun-Do; Jung, Hyun Ah

    2015-12-01

    It has been reported that alkaloids derived from Coptis chinensis exert anti-adipogenic activity on 3T3-L1 adipocytes by downregulating peroxisome proliferation-activity receptor-γ (PPAR-γ) and CCAAT/enhancer binding protein-α (C/EBP-α). However, the signaling-based mechanism of the inhibitory role of epiberberine in the early stages of 3T3-L1 adipocyte differentiation is uncharacterized. Here, we show that epiberberine had inhibitory effects on adipocyte differentiation and significantly decreased lipid accumulation by downregulating an adipocyte-specific transcription factor, sterol regulatory element-binding protein-1 (SREBP-1). Furthermore, we observed that epiberberine markedly suppressed the differentiation-mediated phosphorylation of components of both the Raf/mitogen-activated protein kinase 1 (MEK1)/extracellular signal-regulated protein kinase 1/2 (ERK1/2) and AMP-activated protein kinase-α1 (AMPKα)/Akt pathways. In addition, gene expression of fatty acid synthase (FAS) was significantly inhibited by treatment with epiberberine during adipogenesis. These results indicate that the anti-adipogenic mechanism of epiberberine is associated with inhibition of phosphorylation of Raf/MEK1/ERK1/2 and AMPKα/Akt, followed by downregulation of the major transcription factors of adipogenesis, such as PPAR-γ, C/EBP-α, and SREBP-1, and FAS. Taken together, this study suggests that the anti-adipogenic effect of epiberberine is mediated by downregulation of the Raf/MEK1/ERK1/2 and AMPKα/Akt pathways during 3T3-L1 adipocyte differentiation. Moreover, the anti-adipogenic effects of epiberberine were not accompanied by modulation of β-catenin.

  4. Human adipocytes from the subcutaneous superficial layer have greater adipogenic potential and lower PPAR-γ DNA methylation levels than deep layer adipocytes.

    Science.gov (United States)

    Kosaka, Kentaro; Kubota, Yoshitaka; Adachi, Naoki; Akita, Shinsuke; Sasahara, Yoshitaro; Kira, Tomoe; Kuroda, Masayuki; Mitsukawa, Nobuyuki; Bujo, Hideaki; Satoh, Kaneshige

    2016-08-01

    Human subcutaneous fat tissue consists of two layers, superficial adipose tissue (SAT) and deep adipose tissue (DAT). Some recent reports suggest that a disproportionate accumulation of DAT is related to obesity-associated metabolic complications. However, the differences in adipocyte function between SAT and DAT are unclear. To clarify the differences in human adipocyte characteristics between SAT and DAT, human ceiling culture-derived proliferative adipocytes (ccdPAs) were primary cultured from SAT and DAT of three lean female patients. Differences in adipogenic differentiation potential and sensitivity to exogenous adipogenic factors were examined. Epigenetic modification of the CpG island DNA methylation levels of genes related to adipogenesis was measured. In histological analyses, the mean adipocyte size in SAT was significantly larger than that in DAT (8,741 ± 416 vs. 7,732 ± 213 μm(2), P SAT showed significantly greater adipogenesis than did those of DAT. Sensitivity to partial adipogenic stimulation was significantly different between ccdPAs of SAT and DAT. Peroxisome proliferator-activated receptor-γ (PPAR-γ) protein expression and leptin protein secretion from ccdPAs were significantly higher in SAT than DAT. DNA methylation levels of PPAR-γ were significantly lower in ccdPAs of SAT than DAT. Adipocyte size was larger in SAT than DAT in vivo. This is consistent with the findings of an in vitro study that, compared with ccdPAs in DAT, ccdPAs in SAT have higher adipogenic potential and lower DNA methylation levels of PPAR-γ. PMID:27251439

  5. Determination of osteogenic or adipogenic lineages in muscle-derived stem cells (MDSCs) by a collagen-binding peptide (CBP) derived from bone sialoprotein (BSP)

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yoon Jung [Dental Regenerative Biotechnology Major, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749 (Korea, Republic of); Lee, Jue Yeon [Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Lee, Seung Jin [Department of Industrial Pharmacy, College of Pharmacy, Ewha Womans University, Seoul (Korea, Republic of); Chung, Chong-Pyoung, E-mail: ccpperio@snu.ac.kr [Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Department of Periodontology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul (Korea, Republic of); Park, Yoon Jeong, E-mail: parkyj@snu.ac.kr [Dental Regenerative Biotechnology Major, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749 (Korea, Republic of); Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer CBP sequence is identified from BSP and has collagen binding activity. Black-Right-Pointing-Pointer CBP directly activates the MAPK signaling, especially ERK1/2. Black-Right-Pointing-Pointer CBP increase osteoblastic differentiation by the activation of Runx2. Black-Right-Pointing-Pointer CBP decrease adipogenic differentiation by the inhibition of PPAR{gamma}. -- Abstract: Bone sialoprotein (BSP) is a mineralized, tissue-specific, non-collagenous protein that is normally expressed only in mineralized tissues such as bone, dentin, cementum, and calcified cartilage, and at sites of new mineral formation. The binding of BSP to collagen is thought to be important for initiating bone mineralization and bone cell adhesion to the mineralized matrix. Several recent studies have isolated stem cells from muscle tissue, but their functional properties are still unclear. In this study, we examined the effects of a synthetic collagen-binding peptide (CBP) on the differentiation efficiency of muscle-derived stem cells (MDSCs). The CBP sequence (NGVFKYRPRYYLYKHAYFYPHLKRFPVQ) corresponds to residues 35-62 of bone sialoprotein (BSP), which are located within the collagen-binding domain in BSP. Interestingly, this synthetic CBP inhibited adipogenic differentiation but increased osteogenic differentiation in MDSCs. The CBP also induced expression of osteoblastic marker proteins, including alkaline phosphatase (ALP), type I collagen, Runt-related transcription factor 2 (Runx2), and osteocalcin; prevented adipogenic differentiation in MDSCs; and down-regulated adipose-specific mRNAs, such as adipocyte protein 2 (aP2) and peroxisome proliferator-activated receptor {gamma}. The CBP increased Extracellular signal-regulated kinases (ERK) 1/2 protein phosphorylation, which is important in lineage determination. These observations suggest that this CBP determines the osteogenic or adipogenic lineage in MDSCs by activating ERK1/2. Taken together, a

  6. The Expression of Adipogenic Genes in Adipose Tissues of Feedlot Steers Fed Supplementary Palm Oil or Soybean Oil

    Science.gov (United States)

    Choi, Seong Ho; Park, Sung Kwon; Choi, Chang Weon; Li, Xiang Zi; Kim, Kyoung Hoon; Kim, Won Young; Jeong, Joon; Johnson, Bradley J.; Zan, Linsen; Smith, Stephen B.

    2016-01-01

    We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD) gene expression in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control), with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and α-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha (AMPKα) and peroxisome proliferator-activated receptor gamma (PPARγ) increased between the initial and intermediate biopsies and declined thereafter (p<0.03). SCD gene expression did not change between the initial and intermediate biopsies but declined by over 75% by the final period (p = 0.04), and G-coupled protein receptor 43 (GPR43) gene expression was unaffected by diet or time on trial. Soybean oil decreased (p = 0.01) PPARγ gene expression at the intermediate sample time. At the terminal sample time, PPARγ and SCD gene expression was less in i.m. adipose tissue than in s.c. adipose tissue (p<0.05). AMPKα gene expression was less in s.c. adipose tissue of palm oil-fed steers than in control steers (p = 0.04) and CCAAT enhancer binding protein-beta (CEBPβ) gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (p<0.03). Soybean oil decreased SCD gene expression in s.c. adipose tissue (p = 0.05); SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers

  7. The Expression of Adipogenic Genes in Adipose Tissues of Feedlot Steers Fed Supplementary Palm Oil or Soybean Oil.

    Science.gov (United States)

    Choi, Seong Ho; Park, Sung Kwon; Choi, Chang Weon; Li, Xiang Zi; Kim, Kyoung Hoon; Kim, Won Young; Jeong, Joon; Johnson, Bradley J; Zan, Linsen; Smith, Stephen B

    2016-03-01

    We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD) gene expression in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control), with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and α-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha (AMPKα) and peroxisome proliferator-activated receptor gamma (PPARγ) increased between the initial and intermediate biopsies and declined thereafter (p<0.03). SCD gene expression did not change between the initial and intermediate biopsies but declined by over 75% by the final period (p = 0.04), and G-coupled protein receptor 43 (GPR43) gene expression was unaffected by diet or time on trial. Soybean oil decreased (p = 0.01) PPARγ gene expression at the intermediate sample time. At the terminal sample time, PPARγ and SCD gene expression was less in i.m. adipose tissue than in s.c. adipose tissue (p<0.05). AMPKα gene expression was less in s.c. adipose tissue of palm oil-fed steers than in control steers (p = 0.04) and CCAAT enhancer binding protein-beta (CEBPβ) gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (p<0.03). Soybean oil decreased SCD gene expression in s.c. adipose tissue (p = 0.05); SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers

  8. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on adipogenic differentiation and insulin-induced glucose uptake in 3T3-L1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Hsin-Fen [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Zhunan, Miaoli County 35053, Taiwan (China); Tsou, Tsui-Chun, E-mail: tctsou@nhri.org.tw [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Zhunan, Miaoli County 35053, Taiwan (China); Chao, How-Ran [Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Neipu 912, Pingtung, Taiwan (China); Kuo, Ya-Ting; Tsai, Feng-Yuan; Yeh, Szu-Ching [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Zhunan, Miaoli County 35053, Taiwan (China)

    2010-10-15

    Dioxin exposure has been positively associated with human type II diabetes. Because lipophilic dioxins accumulate mainly in adipose tissue, this study aimed to determine if dioxins induce metabolic dysfunction in fat cells. Using 3T3-L1 cells as an in vitro model, we analyzed the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a model dioxin, on adipogenic differentiation, glucose uptake, and lipolysis. TCDD inhibited adipogenic differentiation, as determined by using oil droplet formation and adipogenic marker gene expression, including PPAR{gamma} (peroxisome proliferator-activated receptor {gamma}), C/EBP{alpha} (CCAAT/enhancer-binding protein {alpha}), and Glut4 (glucose transporter type 4). Effects of TCDD on glucose uptake were evaluated using fully differentiated 3T3-L1 adipocytes, revealing that TCDD significantly attenuated insulin-induced glucose uptake dose dependently. Inhibition of aryl hydrocarbon receptor (AhR) by {alpha}-naphthoflavone ({alpha}-NF), an AhR inhibitor, did not prevent the inhibitory effect of TCDD on glucose uptake, suggesting that TCDD attenuates insulin-induced glucose uptake in an AhR-independent manner. Effects of TCDD on lipolysis were determined using glycerol release assay. We found that TCDD had no marked effect on isoproterenol-induced glycerol release in fully differentiated 3T3-L1 adipocytes. These results provide in vitro evidence of TCDD's effects on fat cell metabolism, suggesting dioxin exposure in development of insulin resistance and type II diabetes.

  9. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on adipogenic differentiation and insulin-induced glucose uptake in 3T3-L1 cells

    International Nuclear Information System (INIS)

    Dioxin exposure has been positively associated with human type II diabetes. Because lipophilic dioxins accumulate mainly in adipose tissue, this study aimed to determine if dioxins induce metabolic dysfunction in fat cells. Using 3T3-L1 cells as an in vitro model, we analyzed the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a model dioxin, on adipogenic differentiation, glucose uptake, and lipolysis. TCDD inhibited adipogenic differentiation, as determined by using oil droplet formation and adipogenic marker gene expression, including PPARγ (peroxisome proliferator-activated receptor γ), C/EBPα (CCAAT/enhancer-binding protein α), and Glut4 (glucose transporter type 4). Effects of TCDD on glucose uptake were evaluated using fully differentiated 3T3-L1 adipocytes, revealing that TCDD significantly attenuated insulin-induced glucose uptake dose dependently. Inhibition of aryl hydrocarbon receptor (AhR) by α-naphthoflavone (α-NF), an AhR inhibitor, did not prevent the inhibitory effect of TCDD on glucose uptake, suggesting that TCDD attenuates insulin-induced glucose uptake in an AhR-independent manner. Effects of TCDD on lipolysis were determined using glycerol release assay. We found that TCDD had no marked effect on isoproterenol-induced glycerol release in fully differentiated 3T3-L1 adipocytes. These results provide in vitro evidence of TCDD's effects on fat cell metabolism, suggesting dioxin exposure in development of insulin resistance and type II diabetes.

  10. Molecular Characterization of Equine APRIL and its Expression Analysis During the Adipogenic Differentiation of Equine Adipose-Derived Stem Cell In Vitro.

    Science.gov (United States)

    Wu, Haitao; Bi, Xiaolin; Cao, Fang; Zhu, Cuicui; Liu, Hongzhen; Song, Jinyun; Ma, Lei; Ma, Li; Zhang, Yi; Zhao, Dongwei; Liu, Hongyan; Xu, Xinzhou; Zhang, Shuangquan

    2016-10-01

    A proliferation inducing ligand (APRIL) is a member of the TNF superfamily. It shares two receptors with B-cell activating factor (BAFF), B-cell maturation antigen (BCMA), and transmembrane activator and CAML interactor (TACI). Herein, the equine APRIL was identified from equine adipose-derived stem cell (ASC), and the protein expression of APRIL and its related molecules were detected during the adipogenic differentiation of equine ASC in vitro. The equine APRIL gene was located on chromosome 11, spans 1852 base pairs (bp). Its open reading frame covers 753 bp, encoding a 250-amino acid protein with the typical TNF structure domain. During the two weeks' adipogenic differentiation of equine ASC, although the protein expression of APRIL and TACI had an insignificant change, that of BCMA increased significantly. Moreover, with the addition of recombinant protein His6-sAPRIL, a reduced differentiation of equine ASC toward adipocyte was detected. These results may provide the basis for investigating the role of APRIL in ASC adipogenic differentiation. PMID:27565870

  11. Aminoglycoside 6′-N-Acetyltransferase Variants of the Ib Type with Altered Substrate Profile in Clinical Isolates of Enterobacter cloacae and Citrobacter freundii

    OpenAIRE

    Casin, Isabelle; Bordon, Florence; Bertin, Philippe; Coutrot, Anne; Podglajen, Isabelle; Brasseur, Robert; Collatz, Ekkehard

    1998-01-01

    Three clinical isolates, Enterobacter cloacae EC1562 and EC1563 and Citrobacter freundii CFr564, displayed an aminoglycoside resistance profile evocative of low-level 6′-N acetyltransferase type II [AAC(6′)-II] production, which conferred reduced susceptibility to gentamicin but not to amikacin or isepamicin. Aminoglycoside acetyltransferase assays suggested the synthesis in the three strains of an AAC(6′) which acetylated amikacin practically as well as it acetylated gentamicin in vitro. Bot...

  12. Yin yang 1 and adipogenic gene network expression in longissimus muscle of beef cattle in response to nutritional management.

    Science.gov (United States)

    Moisá, Sonia J; Shike, Daniel W; Meteer, William T; Keisler, Duane; Faulkner, Dan B; Loor, Juan J

    2013-01-01

    Among 36 differentially-expressed genes during growth in longissimus muscle (LM) of Angus steers, Yin Yang 1 (YY1) had the most relationships with other genes including some associated with adipocyte differentiation. The objective of this study was to examine the effect of nutritional management on mRNA expression of YY1 along with its targets genes PPARG, GTF2B, KAT2B, IGFBP5 and STAT5B. Longissimus from Angus and Angus × Simmental steers (7 total/treatment) on early weaning plus high-starch (EWS), normal weaning plus starch creep feeding (NWS), or normal weaning without starch creep feeding (NWN) was biopsied at 0, 96, and 240 days on treatments. Results suggest that YY1 does not exert control of adipogenesis in LM, and its expression is not sensitive to weaning age. Among the YY1-related genes, EWS led to greater IGFBP5 during growing and finishing phases. Pro-adipogenic transcriptional regulation was detected in EWS due to greater PPARG and VDR at 96 and 240 d vs. 0 d. GTF2B and KAT2B expression was lower in response to NWS and EWS than NWN, and was most pronounced at 240 d. The increase in PPARG and GTF2B expression between 96 and 240 d underscored the existence of a molecular programming mechanism that was sensitive to age and dietary starch. Such response partly explains the greater carcass fat deposition observed in response to NWS. PMID:23700364

  13. Adipogenic Activity of Wild Populations of Rhododendron groenlandicum, a Medicinal Shrub from the James Bay Cree Traditional Pharmacopeia

    Directory of Open Access Journals (Sweden)

    Michel Rapinski

    2015-01-01

    Full Text Available The traditional medicinal plant, Labrador tea (Rhododendron groenlandicum (Oeder Kron & Judd; Ericaceae, present in the pharmacopoeia of the Cree of Eeyou Istchee, has shown glitazone-like activity in the 3T3-L1 adipogenesis bioassay. This activity has been attributed to phenolic compounds, which have been shown to vary in this plant as a function of insolation parameters. The goal of this study was to determine if these changes in phenolic content were pharmacologically significant. Leaves were harvested in 2006 throughout the James Bay region of Northern Quebec and ethanol extracts were tested in vitro using the 3T3-L1 murine cell line adipogenesis bioassay. This traditional medicinal plant was found active in the assay. However, there was no detectable spatial pattern in the accumulation of intracellular triglycerides, suggesting that such patterns previously observed in the phenolic profile of Labrador tea were not pharmacologically significant. Nonetheless, a reduction in the adipogenic activity was observed and associated with higher concentrations of quercetin for which selected environmental variables did not appropriately explain its variation.

  14. Phenolic Composition, Antioxidant Activity and Anti-Adipogenic Effect of Hot Water Extract from Safflower (Carthamus tinctorius L. Seed

    Directory of Open Access Journals (Sweden)

    Seok-Yeong Yu

    2013-11-01

    Full Text Available This study was to evaluate the phenolic content and composition of Carthamus tinctorius L. seed extract (CSE and to further assess its antioxidant and anti-adipogenic activities using various radical scavenging systems and 3T3-L1 cells. Our results show that the total phenolic and flavonoid contents of CSE were 126.0 ± 2.4 mg GAE/g and 62.2 ± 1.9 mg QE/g, respectively. The major phenolic compounds in CSE was (−-epigallocatechin (109.62 mg/g, with a 4-hydroxy benzhydrazide derivative and gallocatechin present at 18.28 mg/g and 17.02 mg/g, respectively. CSE exhibited remarkable radical scavenging activities, FRAP (ferric reducing antioxidant power and reducing power in a dose-dependent manner. Moreover, the oxygen radical absorbance capacity (ORAC value of CSE (0.1 mg/mL was 62.9 ± 4.7 μM TE (trolox equivalent/g. During adipogenesis, CSE significantly inhibited fat accumulation in 3T3-L1 cells compared with control cells. Overall, these results indicate that CSE might be a valuable source of bioactive compounds that impart functional food and natural antioxidant properties.

  15. Mechanism of Butyrate Stimulation of Triglyceride Storage and Adipokine Expression during Adipogenic Differentiation of Porcine Stromovascular Cells.

    Directory of Open Access Journals (Sweden)

    Hui Yan

    Full Text Available Short chain fatty acids (SCFA, products of microbial fermentation of dietary fiber, exert multiple metabolic effects in cells. Previously, we had demonstrated that soluble fiber influenced fat mass accumulation, gut microbial community structure and SCFA production in pigs. The current study was designed to identify effects of SCFA treatment during adipogenic differentiation of porcine stromovascular cells on lipid metabolism and adipokine expression. Differentiating cells were treated with varying concentrations of butyrate. Results show that butyrate treatment enhanced adipogenesis and lipid accumulation, perhaps through upregulation of glucose uptake and de novo lipogenesis and other mechanisms that include induction of SREBP-1c, C/EBPα/β, GLUT4, LPL, PPARγ, GPAT4, DGAT1 and DGAT2 expression. In addition, butyrate induced adiponectin expression, resulting in activation of downstream target genes, such as AMPK and AKT. Activation of AMPK by butyrate led to phosphorylation of ACC. Although increased ACO gene expression was seen with butyrate treatment, experiments with the peroxisomal fatty acid inhibitor, thioridazine, suggest that butyrate may have an inhibitory effect on peroxisomal fatty acid oxidation. Our studies also provide evidence that butyrate may inhibit lipolysis, perhaps in an FFAR3-dependent manner. Therefore, this study presents a novel paradigm for butyrate action in adipocytes and shows that adipocytes are capable of utilizing butyrate, leading to increased expression of adiponectin for enhanced glucose uptake and improved insulin sensitivity.

  16. Heat Shock Protein Augmentation of Angelica gigas Nakai Root Hot Water Extract on Adipogenic Differentiation in Murine 3T3-L1 Preadipocytes.

    Science.gov (United States)

    Lumbera, Wenchie Marie L; Dela Cruz, Joseph; Yang, Seung-Hak; Hwang, Seong Gu

    2016-03-01

    There is a high association of heat shock on the alteration of energy and lipid metabolism. The alterations associated with thermal stress are composed of gene expression changes and adaptation through biochemical responses. Previous study showed that Angelica gigas Nakai (AGN) root extract promoted adipogenic differentiation in murine 3T3-L1 preadipocytes under the normal temperature condition. However, its effect in heat shocked 3T3-L1 cells has not been established. In this study, we investigated the effect of AGN root hot water extract in the adipogenic differentiation of murine 3T3-L1 preadipocytes following heat shock and its possible mechanism of action. Thermal stress procedure was executed within the same stage of preadipocyte confluence (G0) through incubation at 42°C for one hour and then allowed to recover at normal incubation temperature of 37°C for another hour before AGN treatment for both cell viability assay and Oil Red O. Cell viability assay showed that AGN was able to dose dependently (0 to 400 μg/mL) increase cell proliferation under normal incubation temperature and also was able to prevent cytotoxicity due to heat shock accompanied by cell proliferation. Confluent preadipocytes were subjected into heat shock procedure, recovery and then AGN treatment prior to stimulation with the differentiation solution. Heat shocked preadipocytes exhibited reduced differentiation as supported by decreased amount of lipid accumulation in Oil Red O staining and triglyceride measurement. However, those heat shocked preadipocytes that then were given AGN extract showed a dose dependent increase in lipid accumulation as shown by both evaluation procedures. In line with these results, real-time polymerase chain reaction (RT-PCR) and Western blot analysis showed that AGN increased adipogenic differentiation by upregulating heat shock protection related genes and proteins together with the adipogenic markers. These findings imply the potential of AGN in heat

  17. Mutation of the CH1 Domain in the Histone Acetyltransferase CREBBP Results in Autism-Relevant Behaviors in Mice

    OpenAIRE

    Fei Zheng; Lawryn H Kasper; Bedford, David C.; Stephanie Lerach; Teubner, Brett J.W.; Brindle, Paul K.

    2016-01-01

    Autism spectrum disorders (ASDs) are a group of neurodevelopmental afflictions characterized by repetitive behaviors, deficits in social interaction, and impaired communication skills. For most ASD patients, the underlying causes are unknown. Genetic mutations have been identified in about 25 percent of ASD cases, including mutations in epigenetic regulators, suggesting that dysregulated chromatin or DNA function is a critical component of ASD. Mutations in the histone acetyltransferase CREB ...

  18. Co-expression of G2-EPSPS and glyphosate acetyltransferase GAT genes conferring high tolerance to glyphosate in soybean

    OpenAIRE

    Guo, Bingfu; Guo, Yong; Hong, Huilong; Jin, Longguo; Zhang, Lijuan; Chang, Ru-Zhen; Lu, Wei; Lin, Min; Qiu, Li-Juan

    2015-01-01

    Glyphosate is a widely used non-selective herbicide with broad spectrum of weed control around the world. At present, most of the commercial glyphosate tolerant soybeans utilize glyphosate tolerant gene CP4-EPSPS or glyphosate acetyltransferase gene GAT separately. In this study, both glyphosate tolerant gene G2-EPSPS and glyphosate degraded gene GAT were co-transferred into soybean and transgenic plants showed high tolerance to glyphosate. Molecular analysis including PCR, Sothern blot, qRT-...

  19. Cohesin acetyltransferase Esco2 is a cell viability factor and is required for cohesion in pericentric heterochromatin

    OpenAIRE

    Whelan, Gabriela; Kreidl, Emanuel; Wutz, Gordana; Egner, Alexander; Peters, Jan-Michael; Eichele, Gregor

    2012-01-01

    Sister chromatid cohesion, mediated by cohesin and regulated by Sororin, is essential for chromosome segregation. In mammalian cells, cohesion establishment and Sororin recruitment to chromatin‐bound cohesin depends on the acetyltransferases Esco1 and Esco2. Mutations in Esco2 cause Roberts syndrome, a developmental disease in which mitotic chromosomes have a ‘railroad’ track morphology. Here, we show that Esco2 deficiency leads to termination of mouse development at pre‐ and post‐implantatio...

  20. N-Acetyltransferase 1 (NAT1) Genotype: A Risk Factor for Urinary Bladder Cancer in a Lebanese Population

    OpenAIRE

    Yassine, Ibrahim A.; Loulou Kobeissi; Jabbour, Michel E.; Dhaini, Hassan R

    2012-01-01

    In Lebanon, bladder cancer is the second most incident cancer among men. This study investigates a possible association between N-acetyltransferase 1 (NAT1) genotype, a drug-metabolizing enzyme coding gene, and bladder cancer in Lebanese men. A case-control study (54 cases and 105 hospital-based controls) was conducted in two major hospitals in Beirut. Cases were randomly selected from patients diagnosed in the period of 2002–2008. Controls were conveniently identified and selected from the s...

  1. Homologues of xenobiotic metabolizing N-acetyltransferases in plant-associated fungi: Novel functions for an old enzyme family

    OpenAIRE

    Karagianni, Eleni P.; Evanthia Kontomina; Britton Davis; Barbara Kotseli; Theodora Tsirka; Vasiliki Garefalaki; Edith Sim; Glenn, Anthony E; Sotiria Boukouvala

    2015-01-01

    Plant-pathogenic fungi and their hosts engage in chemical warfare, attacking each other with toxic products of secondary metabolism and defending themselves via an arsenal of xenobiotic metabolizing enzymes. One such enzyme is homologous to arylamine N-acetyltransferase (NAT) and has been identified in Fusarium infecting cereal plants as responsible for detoxification of host defence compound 2-benzoxazolinone. Here we investigate functional diversification of NAT enzymes in crop-compromising...

  2. The histone acetyltransferase p300 inhibitor C646 reduces pro-inflammatory gene expression and inhibits histone deacetylases

    Science.gov (United States)

    van den Bosch, Thea; Boichenko, Alexander; Leus, Niek G. J.; Eleni Ourailidou, Maria; Wapenaar, Hannah; Rotili, Dante; Mai, Antonello; Imhof, Axel; Bischoff, Rainer; Haisma, Hidde J.; Dekker, Frank J.

    2016-01-01

    Lysine acetylations are reversible posttranslational modifications of histone and non-histone proteins that play important regulatory roles in signal transduction cascades and gene expression. Lysine acetylations are regulated by histone acetyltransferases as writers and histone deacetylases as erasers. Because of their role in signal transduction cascades, these enzymes are important players in inflammation. Therefore, applications of histone acetyltransferase inhibitors to reduce inflammatory responses are interesting. Among the few histone acetyltransferase inhibitors described, C646 is one of the most potent (Ki of 0.4 μM for histone acetyltransferase p300). C646 was described to regulate the NF-κB pathway; an important pathway in inflammatory responses, which is regulated by acetylation. Interestingly, this pathway has been implicated in asthma and COPD. Therefore we hypothesized that via regulation of the NF-κB signaling pathway, C646 can inhibit pro-inflammatory gene expression, and have potential for the treatment of inflammatory lung diseases. In line with this, here we demonstrate that C646 reduces pro-inflammatory gene expression in RAW264.7 murine macrophages and murine precision-cut lung slices. To unravel its effects on cellular substrates we applied mass spectrometry and found, counterintuitively, a slight increase in acetylation of histone H3. Based on this finding, and structural features of C646, we presumed inhibitory activity of C646 on histone deacetylases, and indeed found inhibition of histone deacetylases from 7 μM and higher concentrations. This indicates that C646 has potential for further development towards applications in the treatment of inflammation, however, its newly discovered lack of selectivity at higher concentrations needs to be taken into account. PMID:26718586

  3. Two N-Terminal Acetyltransferases Antagonistically Regulate the Stability of a Nod-Like Receptor in Arabidopsis

    Science.gov (United States)

    Li, Lin; Gannon, Patrick; Linster, Eric; Huber, Monika; Kapos, Paul; Bienvenut, Willy; Giglione, Carmela; Zhang, Yuelin; Chen, She

    2015-01-01

    Nod-like receptors (NLRs) serve as immune receptors in plants and animals. The stability of NLRs is tightly regulated, though its mechanism is not well understood. Here, we show the crucial impact of N-terminal acetylation on the turnover of one plant NLR, Suppressor of NPR1, Constitutive 1 (SNC1), in Arabidopsis thaliana. Genetic and biochemical analyses of SNC1 uncovered its multilayered regulation by different N-terminal acetyltransferase (Nat) complexes. SNC1 exhibits a few distinct N-terminal isoforms generated through alternative initiation and N-terminal acetylation. Its first Met is acetylated by N-terminal acetyltransferase complex A (NatA), while the second Met is acetylated by N-terminal acetyltransferase complex B (NatB). Unexpectedly, the NatA-mediated acetylation serves as a degradation signal, while NatB-mediated acetylation stabilizes the NLR protein, thus revealing antagonistic N-terminal acetylation of a single protein substrate. Moreover, NatA also contributes to the turnover of another NLR, RESISTANCE TO P. syringae pv maculicola 1. The intricate regulation of protein stability by Nats is speculated to provide flexibility for the target protein in maintaining its homeostasis. PMID:25966763

  4. Identification of critical residues of the serotype modifying O-acetyltransferase of Shigella flexneri

    Directory of Open Access Journals (Sweden)

    Thanweer Farzaana

    2012-07-01

    Full Text Available Abstract Background Thirteen serotypes of Shigella flexneri (S. flexneri have been recognised, all of which are capable of causing bacillary dysentery or shigellosis. With the emergence of the newer S. flexneri serotypes, the development of an effective vaccine has only become more challenging. One of the factors responsible for the generation of serotype diversity is an LPS O-antigen modifying, integral membrane protein known as O-acetyltransferase or Oac. Oac functions by adding an acetyl group to a specific O-antigen sugar, thus changing the antigenic signature of the parent S. flexneri strain. Oac is a membrane protein, consisting of hydrophobic and hydrophilic components. Oac bears homology to several known and predicted acetyltransferases with most homology existing in the N-terminal transmembrane (TM regions. Results In this study, the conserved motifs in the TM regions and in hydrophilic loops of S. flexneri Oac were targeted for mutagenesis with the aim of identifying the amino acid residues essential for the function of Oac. We previously identified three critical arginines–R73, R75 and R76 in the cytoplasmic loop 3 of Oac. Re-establishing that these arginines are critical, in this study we suggest a catalytic role for R73 and a structural role for R75 and R76 in O-acetylation. Serine-glycine motifs (SG 52–53, GS 138–139 and SYG 274–276, phenylalanine-proline motifs (FP 78–79 and FPV 282–84 and a tryptophan-threonine motif (WT141-142 found in TM segments and residues RK 110–111, GR 269–270 and D333 found in hydrophilic loops were also found to be critical to Oac function. Conclusions By studying the effect of the mutations on Oac’s function and assembly, an insight into the possible roles played by the chosen amino acids in Oac was gained. The transmembrane serine-glycine motifs and hydrophilic residues (RK 110–111, GR 269–270 and D333 were shown to have an affect on Oac assembly which suggests a structural role

  5. Acetyl Coenzyme A Acetyltransferase of Rhizobium sp. (Cicer) Strain CC 1192.

    Science.gov (United States)

    Kim, S A; Copeland, L

    1997-09-01

    To investigate why Rhizobium sp. (Cicer) strain CC 1192 cells accumulate poly-R-3-hydroxybutyrate in the free-living state but not as bacteroids in nodules on chickpea (Cicer arietinum L.) plants, we have examined the kinetic properties of acetyl coenzyme A (acetyl-CoA) acetyltransferase (also known as acetoacetyl-CoA thiolase and 3-ketothiolase [EC 2.3.1.9]) from both types of cells. The enzyme had a native molecular mass of 180 (plusmn) 4 kDa, and the subunit molecular mass was 44 (plusmn) 1 kDa. The seven amino acids from the N terminus were Lys-Ala-Ser-Ile-Val-Ile-Ala. Thiolysis and condensation activity of the enzyme from free-living CC 1192 cells were optimal at pHs 7.8 and 8.1, respectively. The relationship between substrate concentrations and initial velocity for the thiolysis reaction were hyperbolic and gave K(infm) values for acetoacetyl-CoA and CoA of 42 and 56 (mu)M, respectively. The maximum velocity in the condensation direction was approximately 10% of that of the thiolysis reaction. With highly purified preparations of the enzyme, a value of approximately 1 mM was determined for the apparent K(infm) for acetyl-CoA. However, with partially purified enzyme preparations or when N-ethylmaleimide was included in reaction mixtures the apparent K(infm) for acetyl-CoA was close to 0.3 mM. In the condensation direction, CoA was a potent linear competitive inhibitor with an inhibition constant of 11 (mu)M. The much higher affinity of the enzyme for the product CoA than the substrate acetyl-CoA could have significance in view of metabolic differences between bacteroid and free-living cells of CC 1192. We propose that in free-living CC 1192 cells, the acetyl-CoA/CoA ratio reaches a value that allows condensation activity of acetyl-CoA acetyltransferase, but that in CC 1192 bacteroids, the ratio is poised so that the formation of acetoacetyl-CoA is not favored.

  6. Novel ligands of Choline Acetyltransferase designed by in silico molecular docking, hologram QSAR and lead optimization.

    Science.gov (United States)

    Kumar, Rajnish; Långström, Bengt; Darreh-Shori, Taher

    2016-01-01

    Recent reports have brought back the acetylcholine synthesizing enzyme, choline acetyltransferase in the mainstream research in dementia and the cholinergic anti-inflammatory pathway. Here we report, a specific strategy for the design of novel ChAT ligands based on molecular docking, Hologram Quantitative Structure Activity Relationship (HQSAR) and lead optimization. Molecular docking was performed on a series of ChAT inhibitors to decipher the molecular fingerprint of their interaction with the active site of ChAT. Then robust statistical fragment HQSAR models were developed. A library of novel ligands was generated based on the pharmacophoric and shape similarity scoring function, and evaluated in silico for their molecular interactions with ChAT. Ten of the top scoring invented compounds are reported here. We confirmed the activity of α-NETA, the only commercially available ChAT inhibitor, and one of the seed compounds in our model, using a new simple colorimetric ChAT assay (IC50 ~ 88 nM). In contrast, α-NETA exhibited an IC50 of ~30 μM for the ACh-degrading cholinesterases. In conclusion, the overall results may provide useful insight for discovering novel ChAT ligands and potential positron emission tomography tracers as in vivo functional biomarkers of the health of central cholinergic system in neurodegenerative disorders, such as Alzheimer's disease.

  7. N-Acetyltransferase 2 genotype, exfoliated urothelial cells and benzidine exposure.

    Science.gov (United States)

    Ma, Qing-wen; Lin, Guo-fang; Chen, Ji-gang; Guo, Wei-Chao; Qin, Yi-qiu; Golka, Klaus; Shen, Jian-hua

    2012-01-01

    Most studies report an association of the slow N-acetyltransferase 2 (NAT2) status with elevated bladder cancer risk. In this study, NAT2 genotypes and the decades-long records of Papanicolaou's grading of exfoliated urothelial cells in a former benzidine-exposed cohort of the Shanghai dyestuff industry (29 bladder cancer patients; 307 non-cancer cohort members, some of them presenting different grades of pre-malignant alterations of exfoliated urothelial cells) were investigated. The cohort members had been enrolled in regular medical surveillance since mid-1980s. No overall increase of slow NAT2 genotypes in the former benzidine-exposed bladder cancer patients was found, compared with non-diseased members of the same cohort. A lower presentation of the homozygous wild genotype NAT2 4/4 was observed in bladder cancer patients, compared with non-diseased members with averaged Papanicolaou's grading (APG)3 II (OR=0.31, 95 percent CI 0.10-0.96, p=0.034) or with APG less than II (OR=0.36,95 percent CI 0.12-1.10, p=0.063). Nevertheless, neither a protective influence of rapid NAT2 genotypes on bladder cancer risk nor on pre-malignant cytological alterations could be confirmed by the present data.

  8. Human Neural Stem Cells Overexpressing Choline Acetyltransferase Restore Unconditioned Fear in Rats with Amygdala Injury

    Directory of Open Access Journals (Sweden)

    Kyungha Shin

    2016-01-01

    Full Text Available Amygdala is involved in the fear memory that recognizes certain environmental cues predicting threatening events. Manipulation of neurotransmission within the amygdala affects the expression of conditioned and unconditioned emotional memories such as fear freezing behaviour. We previously demonstrated that F3.ChAT human neural stem cells (NSCs overexpressing choline acetyltransferase (ChAT improve cognitive function of Alzheimer’s disease model rats with hippocampal or cholinergic nerve injuries by increasing acetylcholine (ACh level. In the present study, we examined the effect of F3.ChAT cells on the deficit of unconditioned fear freezing. Rats given N-methyl-d-aspartate (NMDA in their amygdala 2 weeks prior to cat odor exposure displayed very short resting (freezing time compared to normal animals. NMDA induced neuronal degeneration in the amygdala, leading to a decreased ACh concentration in cerebrospinal fluid. However, intracerebroventricular transplantation of F3.ChAT cells attenuated amygdala lesions 4 weeks after transplantation. The transplanted cells were found in the NMDA-injury sites and produced ChAT protein. In addition, F3.ChAT-receiving rats recuperated freezing time staying remote from the cat odor source, according to the recovery of brain ACh concentration. The results indicate that human NSCs overexpressing ChAT may facilitate retrieval of unconditioned fear memory by increasing ACh level.

  9. Human Neural Stem Cells Overexpressing Choline Acetyltransferase Restore Unconditioned Fear in Rats with Amygdala Injury.

    Science.gov (United States)

    Shin, Kyungha; Cha, Yeseul; Kim, Kwang Sei; Choi, Ehn-Kyoung; Choi, Youngjin; Guo, Haiyu; Ban, Young-Hwan; Kim, Jong-Choon; Park, Dongsun; Kim, Yun-Bae

    2016-01-01

    Amygdala is involved in the fear memory that recognizes certain environmental cues predicting threatening events. Manipulation of neurotransmission within the amygdala affects the expression of conditioned and unconditioned emotional memories such as fear freezing behaviour. We previously demonstrated that F3.ChAT human neural stem cells (NSCs) overexpressing choline acetyltransferase (ChAT) improve cognitive function of Alzheimer's disease model rats with hippocampal or cholinergic nerve injuries by increasing acetylcholine (ACh) level. In the present study, we examined the effect of F3.ChAT cells on the deficit of unconditioned fear freezing. Rats given N-methyl-d-aspartate (NMDA) in their amygdala 2 weeks prior to cat odor exposure displayed very short resting (freezing) time compared to normal animals. NMDA induced neuronal degeneration in the amygdala, leading to a decreased ACh concentration in cerebrospinal fluid. However, intracerebroventricular transplantation of F3.ChAT cells attenuated amygdala lesions 4 weeks after transplantation. The transplanted cells were found in the NMDA-injury sites and produced ChAT protein. In addition, F3.ChAT-receiving rats recuperated freezing time staying remote from the cat odor source, according to the recovery of brain ACh concentration. The results indicate that human NSCs overexpressing ChAT may facilitate retrieval of unconditioned fear memory by increasing ACh level. PMID:27087745

  10. Andrographolide: A potent antituberculosis compound that targets Aminoglycoside 2'-N-acetyltransferase in Mycobacterium tuberculosis.

    Science.gov (United States)

    Prabu, Amudha; Hassan, Sameer; Prabuseenivasan; Shainaba, A S; Hanna, L E; Kumar, Vanaja

    2015-09-01

    Tuberculosis (TB) still remains a major challenging infectious disease. The increased rate of emergence of multi-drug resistant and extensively-drug resistant strains of the organism has further complicated the situation, resulting in an urgent need for new anti-TB drugs. Antimycobacterial activity of Andrographis paniculata was evaluated using a rapid LRP assay and the probable targets were identified by docking analysis. The methanolic extract of A. paniculata showed maximum antimycobacterial activity at 250μg/ml against all the tested strains of M. tuberculosis (H37Rv, MDR, and drug sensitive). Based on bioassay guided fractionation, andrographolide was identified as the potent molecule. With the docking analysis, both ICDH (Isocitrate Dehydrogenase) and AAC (Aminoglycoside 2'-N-acetyltransferase) were predicted as targets of andrographolide in M. tuberculosis. Molecular simulation revealed that, ICDH showed low binding affinity to andrographolide. However, for AAC, the andrographolide was observed to be well within the active site after 10ns of molecular simulation. This suggests that ACC (PDB ID 1M4I) could be the probable target for andrographolide. PMID:26245695

  11. Structural Analysis of a Putative Aminoglycoside N-Acetyltransferase from Bacillus anthracis

    Energy Technology Data Exchange (ETDEWEB)

    Klimecka, Maria M.; Chruszcz, Maksymilian; Font, Jose; Skarina, Tatiana; Shumilin, Igor; Onopryienko, Olena; Porebski, Przemyslaw J.; Cymborowski, Marcin; Zimmerman, Matthew D.; Hasseman, Jeremy; Glomski, Ian J.; Lebioda, Lukasz; Savchenko, Alexei; Edwards, Aled; Minor, Wladek (SC); (Toronto); (UV)

    2012-02-15

    For the last decade, worldwide efforts for the treatment of anthrax infection have focused on developing effective vaccines. Patients that are already infected are still treated traditionally using different types of standard antimicrobial agents. The most popular are antibiotics such as tetracyclines and fluoroquinolones. While aminoglycosides appear to be less effective antimicrobial agents than other antibiotics, synthetic aminoglycosides have been shown to act as potent inhibitors of anthrax lethal factor and may have potential application as antitoxins. Here, we present a structural analysis of the BA2930 protein, a putative aminoglycoside acetyltransferase, which may be a component of the bacterium's aminoglycoside resistance mechanism. The determined structures revealed details of a fold characteristic only for one other protein structure in the Protein Data Bank, namely, YokD from Bacillus subtilis. Both BA2930 and YokD are members of the Antibiotic-NAT superfamily (PF02522). Sequential and structural analyses showed that residues conserved throughout the Antibiotic-NAT superfamily are responsible for the binding of the cofactor acetyl coenzyme A. The interaction of BA2930 with cofactors was characterized by both crystallographic and binding studies.

  12. The Aspergillus flavus Histone Acetyltransferase AflGcnE Regulates Morphogenesis, Aflatoxin Biosynthesis, and Pathogenicity

    Science.gov (United States)

    Lan, Huahui; Sun, Ruilin; Fan, Kun; Yang, Kunlong; Zhang, Feng; Nie, Xin Y.; Wang, Xiunai; Zhuang, Zhenhong; Wang, Shihua

    2016-01-01

    Histone acetyltransferases (HATs) help regulate fungal development and the production of secondary metabolites. In this study, we determined that the HAT AflGcnE influenced morphogenesis and aflatoxin biosynthesis in Aspergillus flavus. We observed that AflGcnE localized to the nucleus and cytoplasm during the conidial production and germination stages, while it was located mainly in the nucleus during the hyphal development stage. Deletion of AflgcnE inhibited the growth of A. flavus and decreased the hydrophobicity of the cell surface. The ΔAflgcnE mutant exhibited a lack of asexual sporulation and was unable to generate sclerotia. Additionally, AflgcnE was required to maintain cell wall integrity and genotoxic stress responses. Importantly, the ΔAflgcnE mutant did not produce aflatoxins, which was consistent with a significant down-regulation of aflatoxin gene expression levels. Furthermore, our data revealed that AflgcnE is a pathogenicity factor required for colonizing maize seeds. In summary, we revealed that A. flavus AflGcnE is crucial for morphological development, aflatoxin biosynthesis, stress responses, and pathogenicity. Our findings help clarify the functional divergence of GcnE orthologs, and may provide a possible target for controlling A. flavus infections of agriculturally important crops. PMID:27625637

  13. The lysine acetyltransferase activator Brpf1 governs dentate gyrus development through neural stem cells and progenitors.

    Directory of Open Access Journals (Sweden)

    Linya You

    2015-03-01

    Full Text Available Lysine acetylation has recently emerged as an important post-translational modification in diverse organisms, but relatively little is known about its roles in mammalian development and stem cells. Bromodomain- and PHD finger-containing protein 1 (BRPF1 is a multidomain histone binder and a master activator of three lysine acetyltransferases, MOZ, MORF and HBO1, which are also known as KAT6A, KAT6B and KAT7, respectively. While the MOZ and MORF genes are rearranged in leukemia, the MORF gene is also mutated in prostate and other cancers and in four genetic disorders with intellectual disability. Here we show that forebrain-specific inactivation of the mouse Brpf1 gene causes hypoplasia in the dentate gyrus, including underdevelopment of the suprapyramidal blade and complete loss of the infrapyramidal blade. We trace the developmental origin to compromised Sox2+ neural stem cells and Tbr2+ intermediate neuronal progenitors. We further demonstrate that Brpf1 loss deregulates neuronal migration, cell cycle progression and transcriptional control, thereby causing abnormal morphogenesis of the hippocampus. These results link histone binding and acetylation control to hippocampus development and identify an important epigenetic regulator for patterning the dentate gyrus, a brain structure critical for learning, memory and adult neurogenesis.

  14. Environmental History Modulates Arabidopsis Pattern-Triggered Immunity in a HISTONE ACETYLTRANSFERASE1-Dependent Manner.

    Science.gov (United States)

    Singh, Prashant; Yekondi, Shweta; Chen, Po-Wen; Tsai, Chia-Hong; Yu, Chun-Wei; Wu, Keqiang; Zimmerli, Laurent

    2014-06-24

    In nature, plants are exposed to a fluctuating environment, and individuals exposed to contrasting environmental factors develop different environmental histories. Whether different environmental histories alter plant responses to a current stress remains elusive. Here, we show that environmental history modulates the plant response to microbial pathogens. Arabidopsis thaliana plants exposed to repetitive heat, cold, or salt stress were more resistant to virulent bacteria than Arabidopsis grown in a more stable environment. By contrast, long-term exposure to heat, cold, or exposure to high concentrations of NaCl did not provide enhanced protection against bacteria. Enhanced resistance occurred with priming of Arabidopsis pattern-triggered immunity (PTI)-responsive genes and the potentiation of PTI-mediated callose deposition. In repetitively stress-challenged Arabidopsis, PTI-responsive genes showed enrichment for epigenetic marks associated with transcriptional activation. Upon bacterial infection, enrichment of RNA polymerase II at primed PTI marker genes was observed in environmentally challenged Arabidopsis. Finally, repetitively stress-challenged histone acetyltransferase1-1 (hac1-1) mutants failed to demonstrate enhanced resistance to bacteria, priming of PTI, and increased open chromatin states. These findings reveal that environmental history shapes the plant response to bacteria through the development of a HAC1-dependent epigenetic mark characteristic of a primed PTI response, demonstrating a mechanistic link between the primed state in plants and epigenetics.

  15. Molecular Evolution of Multiple Arylalkylamine N-Acetyltransferase (AANAT in Fish

    Directory of Open Access Journals (Sweden)

    Bina Zilberman-Peled

    2011-05-01

    Full Text Available Arylalkylamine N-acetyltransferase (AANAT catalyzes the transfer of an acetyl group from acetyl coenzyme A (AcCoA to arylalkylamines, including indolethylamines and phenylethylamines. Multiple aanats are present in teleost fish as a result of whole genome and gene duplications. Fish aanat1a and aanat2 paralogs display different patterns of tissue expression and encode proteins with different substrate preference: AANAT1a is expressed in the retina, and acetylates both indolethylamines and phenylethylamines; while AANAT2 is expressed in the pineal gland, and preferentially acetylates indolethylamines. The two enzymes are therefore thought to serve different roles. Here, the molecular changes that led to their specialization were studied by investigating the structure-function relationships of AANATs in the gilthead seabream (sb, Sperus aurata. Acetylation activity of reciprocal mutated enzymes pointed to specific residues that contribute to substrate specificity of the enzymes. Inhibition tests followed by complementary analyses of the predicted three-dimensional models of the enzymes, suggested that both phenylethylamines and indolethylamines bind to the catalytic pocket of both enzymes. These results suggest that substrate selectivity of AANAT1a and AANAT2 is determined by the positioning of the substrate within the catalytic pocket, and its accessibility to catalysis. This illustrates the evolutionary process by which enzymes encoded by duplicated genes acquire different activities and play different biological roles.

  16. Crystal Structures of Murine Carnitine Acetyltransferase in Ternary Complexes with Its Substrates

    Energy Technology Data Exchange (ETDEWEB)

    Hsiao,Y.; Jogl, G.; Tong, L.

    2006-01-01

    Carnitine acyltransferases catalyze the reversible exchange of acyl groups between coenzyme A (CoA) and carnitine. They have important roles in many cellular processes, especially the oxidation of long-chain fatty acids in the mitochondria for energy production, and are attractive targets for drug discovery against diabetes and obesity. To help define in molecular detail the catalytic mechanism of these enzymes, we report here the high resolution crystal structure of wild-type murine carnitine acetyltransferase (CrAT) in a ternary complex with its substrates acetyl-CoA and carnitine, and the structure of the S554A/M564G double mutant in a ternary complex with the substrates CoA and hexanoylcarnitine. Detailed analyses suggest that these structures may be good mimics for the Michaelis complexes for the forward and reverse reactions of the enzyme, representing the first time that such complexes of CrAT have been studied in molecular detail. The structural information provides significant new insights into the catalytic mechanism of CrAT and possibly carnitine acyltransferases in general.

  17. Purification of phosphinothricin acetyltransferase using Reactive brown 10 affinity in a single chromatography step.

    Science.gov (United States)

    Wang, Cunxi; Lee, Thomas C; Crowley, Kathleen S; Bell, Erin

    2013-08-01

    The expression of phosphinothricin N-acetyltransferase (PAT) protein in transgenic plants confers tolerance to the herbicide glufosinate. To enable the characterization of PAT protein expressed in plants, it is necessary to obtain high purity PAT protein from the transgenic grain. Because transgenically expressed proteins are typical present at very low levels (i.e. 0.1-50 μg protein/g grain), a highly specific and efficient purification protocol is required to purify them. Based on the physicochemical properties of PAT, we developed a novel purification method that is simple, time-saving, inexpensive and reproducible. The novel method employs a single chromatography step using a reactive dye resin, Reactive brown 10-agarose. Reactive brown 10 preferentially binds the PAT protein, which can then be specifically released by one of its substrates, acetyl-CoA. Using Reactive brown 10-agarose, PAT protein was purified to homogeneity from cottonseed with high recovery efficiency. As expected, the Reactive brown 10-produced PAT was enzymatically active. Other applications of the method on protein expression and purification, and development of PAT enzymatic inhibitors were also discussed. PMID:23748142

  18. Structural Basis for Microcin C7 Inactivation by the MccE Acetyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Vinayak; Metlitskaya, Anastasiya; Severinov, Konstantin; Nair, Satish K. (Rutgers); (Russ. Acad. Sci.); (UIUC)

    2015-10-15

    The antibiotic microcin C7 (McC) acts as a bacteriocide by inhibiting aspartyl-tRNA synthetase and stalling the protein translation machinery. McC is synthesized as a heptapeptide-nucleotide conjugate, which is processed by cellular peptidases within target strains to yield the biologically active compound. As unwanted processing of intact McC can result in self-toxicity, producing strains utilize multiple mechanisms for autoimmunity against processed McC. We have shown previously that the mccE gene within the biosynthetic cluster can inactivate processed McC by acetylating the antibiotic. Here, we present the characterization of this acetylation mechanism through biochemical and structural biological studies of the MccE acetyltransferase domain (MccE{sup AcTase}). We have also determined five crystal structures of the MccE-acetyl-CoA complex with bound substrates, inhibitor, and reaction product. The structural data reveal an unexpected mode of substrate recognition through p-stacking interactions similar to those found in cap-binding proteins and nucleotidyltransferases. These studies provide a rationale for the observation that MccE{sup AcTase} can detoxify a range of aminoacylnucleotides, including those that are structurally distinct from microcin C7.

  19. An aminoglycoside sensing riboswitch controls the expression of aminoglycoside resistance acetyltransferase and adenyltransferases.

    Science.gov (United States)

    Chen, Dongrong; Murchie, Alastair I H

    2014-10-01

    The emergence of antibiotic resistance in human pathogens is an increasing threat to public health. The fundamental mechanisms that control the high levels of expression of antibiotic resistance genes are not yet completely understood. The aminoglycosides are one of the earliest classes of antibiotics that were introduced in the 1940s. In the clinic aminoglycoside resistance is conferred most commonly through enzymatic modification of the drug although resistance through enzymatic modification of the target rRNA through methylation or the overexpression of efflux pumps is also appearing. An aminoglycoside sensing riboswitch has been identified that controls expression of the aminoglycoside resistance genes that encode the aminoglycoside acetyltransferase (AAC) and aminoglycoside nucleotidyltransferase (ANT) (adenyltransferase (AAD)) enzymes. AAC and ANT cause resistance to aminoglycoside antibiotics through modification of the drugs. Expression of the AAC and ANT resistance genes is regulated by aminoglycoside binding to the 5' leader RNA of the aac/aad genes. The aminoglycoside sensing RNA is also associated with the integron cassette system that captures antibiotic resistance genes. Specific aminoglycoside binding to the leader RNA induces a structural transition in the leader RNA, and consequently induction of resistance protein expression. Reporter gene expression, direct measurements of drug RNA binding, chemical probing and UV cross-linking combined with mutational analysis demonstrated that the leader RNA functioned as an aminoglycoside sensing riboswitch in which drug binding to the leader RNA leads to the induction of aminoglycoside antibiotic resistance. This article is part of a Special Issue entitled: Riboswitches. PMID:24631585

  20. Response of ATP sulfurylase and serine acetyltransferase towards cadmium in hyperaccumulator Sedum alfredii Hance.

    Science.gov (United States)

    Guo, Wei-dong; Liang, Jun; Yang, Xiao-e; Chao, Yue-en; Feng, Ying

    2009-04-01

    We studied the responses of the activities of adenosine-triphosphate (ATP) sulfurylase (ATPS) and serine acetyltransferase (SAT) to cadmium (Cd) levels and treatment time in hyperaccumulating ecotype (HE) Sedum alfredii Hance, as compared with its non-hyperaccumulating ecotype (NHE). The results show that plant growth was inhibited in NHE but promoted in HE when exposed to high Cd level. Cd concentrations in leaves and shoots rapidly increased in HE rather than in NHE, and they became much higher in HE than in NHE along with increasing treatment time and Cd supply levels. ATPS activity was higher in HE than in NHE in all Cd treatments, and increased with increasing Cd supply levels in both HE and NHE when exposed to Cd treatment within 8 h. However, a marked difference of ATPS activity between HE and NHE was found with Cd treatment for 168 h, where ATPS activity increased in HE but decreased in NHE. Similarly, SAT activity was higher in HE than in NHE at all Cd treatments, but was more sensitive in NHE than in HE. Both ATPS and SAT activities in NHE leaves tended to decrease with increasing treatment time after 8 h at all Cd levels. The results reveal the different responses in sulfur assimilation enzymes and Cd accumulation between HE and NHE. With increasing Cd stress, the activities of sulfur assimilation enzymes (ATPS and SAT) were induced in HE, which may contribute to Cd accumulation in the hyperaccumulator Sedum alfredii Hance. PMID:19353742

  1. Response of ATP sulfurylase and serine acetyltransferase towards cadmium in hyperaccumulator Sedum alfredii Hance

    Institute of Scientific and Technical Information of China (English)

    Wei-dong GUO; Jun LIANG; Xiao-e YANG; Yue-en CHAO; Ying FENG

    2009-01-01

    We studied the responses of the activities of adenosine-triphosphate (ATP) sulfurylase (ATPS) and serine acetyl-transferase (SAT) to cadmium (Cd) levels and treatment time in hyperaccumulating ecotype (HE) Sedum alfredii Hance, as compared with its non-hyperaccumulating ecotype (NHE). The results show that plant growth was inhibited in NHE but promoted in HE when exposed to high Cd level. Cd concentrations in leaves and shoots rapidly increased in HE rather than in NHE, and they became much higher in HE than in NHE along with increasing treatment time and Cd supply levels. ATPS activity was higher in HE than in NHE in all Cd treatments, and increased with increasing Cd supply levels in both HE and NHE when exposed to Cd treatment within 8 h. However, a marked difference of ATPS activity between HE and NHE was found with Cd treatment for 168 h, where ATPS activity increased in HE but decreased in NHE. Similarly, SAT activity was higher in HE than in NHE at all Cd treatments, but was more sensitive in NHE than in HE. Both ATPS and SAT activities in NHE leaves tended to decrease with increasing treatment time after 8 h at all Cd levels. The results reveal the different responses in sulfur assimilation enzymes and Cd accumulation between HE and NHE. With increasing Cd stress, the activities of sulfur assimilation enzymes (ATPS and SAT) were induced in HE, which may contribute to Cd accumulation in the hyperaccumulator Sedum alfredii Hance.

  2. Response of ATP sulfurylase and serine acetyltransferase towards cadmium in hyperaccumulator Sedum alfredii Hance*

    Science.gov (United States)

    Guo, Wei-dong; Liang, Jun; Yang, Xiao-e; Chao, Yue-en; Feng, Ying

    2009-01-01

    We studied the responses of the activities of adenosine-triphosphate (ATP) sulfurylase (ATPS) and serine acetyltransferase (SAT) to cadmium (Cd) levels and treatment time in hyperaccumulating ecotype (HE) Sedum alfredii Hance, as compared with its non-hyperaccumulating ecotype (NHE). The results show that plant growth was inhibited in NHE but promoted in HE when exposed to high Cd level. Cd concentrations in leaves and shoots rapidly increased in HE rather than in NHE, and they became much higher in HE than in NHE along with increasing treatment time and Cd supply levels. ATPS activity was higher in HE than in NHE in all Cd treatments, and increased with increasing Cd supply levels in both HE and NHE when exposed to Cd treatment within 8 h. However, a marked difference of ATPS activity between HE and NHE was found with Cd treatment for 168 h, where ATPS activity increased in HE but decreased in NHE. Similarly, SAT activity was higher in HE than in NHE at all Cd treatments, but was more sensitive in NHE than in HE. Both ATPS and SAT activities in NHE leaves tended to decrease with increasing treatment time after 8 h at all Cd levels. The results reveal the different responses in sulfur assimilation enzymes and Cd accumulation between HE and NHE. With increasing Cd stress, the activities of sulfur assimilation enzymes (ATPS and SAT) were induced in HE, which may contribute to Cd accumulation in the hyperaccumulator Sedum alfredii Hance. PMID:19353742

  3. Inflammatory cytokines suppress arylamine N-acetyltransferase 1 in cholangiocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To evaluate the effect of inflammatory cytokines on arylamine N-acetyltransferase 1 (NAT1), which is a phase-Ⅱ enzyme involved in the biotransformation of aromatic and heterocyclic amines found in food, drugs and the environment.METHODS: Human cholangiocarcinoma KKU-100 cells were treated with a mixture of proinflammatory cytokines (interferon-y, interleukin-1β and tumor necrosis factor-α)for 48 h, and the effect on NAT1 activity was assessed by high performance liquid chromatography, while NAT1 expression was determined by reverse-transcription polymerase chain reaction. The oxidative stress on the cells was examined by the formation of nitric oxide,superoxide anion and glutathione (GSH) levels. The cells were also treated with S-nitroso-glutathione (GSNO), a nitric oxide donor, to see if the responses were similar to those obtained with the inflammatory cytokines.RESULTS: Cytokines suppressed NAT1 activity,reducing the Vmax without affecting the Km. Cytokines also had a significant impact on the induction of nitric oxide production and in reducing the redox ratios of glutathione (GSH) and GSH disulfide. Treatment with GSNO for 2-48 h reduced NAT1 activity without affecting the GSH ratio. Moreover, inflammatory cytokines and GSNO suppressed NAT1 mRNA expression.CONCLUSION: These findings indicate an association between inflammation and suppression of NAT1, which perhaps contributes to chemical-mediated toxicity and carcinogenesis.

  4. Novel ligands of Choline Acetyltransferase designed by in silico molecular docking, hologram QSAR and lead optimization.

    Science.gov (United States)

    Kumar, Rajnish; Långström, Bengt; Darreh-Shori, Taher

    2016-01-01

    Recent reports have brought back the acetylcholine synthesizing enzyme, choline acetyltransferase in the mainstream research in dementia and the cholinergic anti-inflammatory pathway. Here we report, a specific strategy for the design of novel ChAT ligands based on molecular docking, Hologram Quantitative Structure Activity Relationship (HQSAR) and lead optimization. Molecular docking was performed on a series of ChAT inhibitors to decipher the molecular fingerprint of their interaction with the active site of ChAT. Then robust statistical fragment HQSAR models were developed. A library of novel ligands was generated based on the pharmacophoric and shape similarity scoring function, and evaluated in silico for their molecular interactions with ChAT. Ten of the top scoring invented compounds are reported here. We confirmed the activity of α-NETA, the only commercially available ChAT inhibitor, and one of the seed compounds in our model, using a new simple colorimetric ChAT assay (IC50 ~ 88 nM). In contrast, α-NETA exhibited an IC50 of ~30 μM for the ACh-degrading cholinesterases. In conclusion, the overall results may provide useful insight for discovering novel ChAT ligands and potential positron emission tomography tracers as in vivo functional biomarkers of the health of central cholinergic system in neurodegenerative disorders, such as Alzheimer's disease. PMID:27507101

  5. Muscle-specific deletion of carnitine acetyltransferase compromises glucose tolerance and metabolic flexibility.

    Science.gov (United States)

    Muoio, Deborah M; Noland, Robert C; Kovalik, Jean-Paul; Seiler, Sarah E; Davies, Michael N; DeBalsi, Karen L; Ilkayeva, Olga R; Stevens, Robert D; Kheterpal, Indu; Zhang, Jingying; Covington, Jeffrey D; Bajpeyi, Sudip; Ravussin, Eric; Kraus, William; Koves, Timothy R; Mynatt, Randall L

    2012-05-01

    The concept of "metabolic inflexibility" was first introduced to describe the failure of insulin-resistant human subjects to appropriately adjust mitochondrial fuel selection in response to nutritional cues. This phenomenon has since gained increasing recognition as a core component of the metabolic syndrome, but the underlying mechanisms have remained elusive. Here, we identify an essential role for the mitochondrial matrix enzyme, carnitine acetyltransferase (CrAT), in regulating substrate switching and glucose tolerance. By converting acetyl-CoA to its membrane permeant acetylcarnitine ester, CrAT regulates mitochondrial and intracellular carbon trafficking. Studies in muscle-specific Crat knockout mice, primary human skeletal myocytes, and human subjects undergoing L-carnitine supplementation support a model wherein CrAT combats nutrient stress, promotes metabolic flexibility, and enhances insulin action by permitting mitochondrial efflux of excess acetyl moieties that otherwise inhibit key regulatory enzymes such as pyruvate dehydrogenase. These findings offer therapeutically relevant insights into the molecular basis of metabolic inflexibility. PMID:22560225

  6. Deletion of host histone acetyltransferases and deacetylases strongly affects Agrobacterium-mediated transformation of Saccharomyces cerevisiae.

    Science.gov (United States)

    Soltani, Jalal; van Heusden, Gerard Paul H; Hooykaas, Paul J J

    2009-09-01

    Agrobacterium tumefaciens is a plant pathogen that genetically transforms plant cells by transferring a part of its Ti-plasmid, the T-strand, to the host cell. Under laboratory conditions, it can also transform cells from many different nonplant organisms, including the yeast Saccharomyces cerevisiae. Collections of S. cerevisiae strains have been developed with systematic deletion of all coding sequences. Here, we used these collections to identify genes involved in the Agrobacterium-mediated transformation (AMT) of S. cerevisiae. We found that deletion of genes (GCN5, NGG1, YAF9 and EAF7) encoding subunits of the SAGA, SLIK, ADA and NuA4 histone acetyltransferase complexes highly increased the efficiency of AMT, while deletion of genes (HDA2, HDA3 and HST4) encoding subunits of histone deacetylase complexes decreased AMT. These effects are specific for AMT as the efficiency of chemical (lithium acetate) transformation was not or only slightly affected by these deletions. Our data are consistent with a positive role of host histone deacetylation in AMT.

  7. N-acetyltransferase Mpr1 confers ethanol tolerance on Saccharomyces cerevisiae by reducing reactive oxygen species

    Energy Technology Data Exchange (ETDEWEB)

    Du, Xiaoyi [Fukui Prefectural Univ., Fukui (Japan). Dept. of Bioscience; Takagi, Hiroshi [Nara Inst. of Science and Technology, Ikoma, Nara (Japan). Graduate School of Biological Sciences

    2007-07-15

    N-Acetyltransferase Mpr1 of Saccharomyces cerevisiae can reduce intracellular oxidation levels and protect yeast cells under oxidative stress, including H{sub 2}O{sub 2}, heat-shock, or freeze-thaw treatment. Unlike many antioxidant enzyme genes induced in response to oxidative stress, the MPR1 gene seems to be constitutively expressed in yeast cells. Based on a recent report that ethanol toxicity is correlated with the production of reactive oxygen species (ROS), we examined here the role of Mpr1 under ethanol stress conditions. The null mutant of the MPR1 and MPR2 genes showed hypersensitivity to ethanol stress, and the expression of the MPR1 gene conferred stress tolerance. We also found that yeast cells exhibited increased ROS levels during exposure to ethanol stress, and that Mpr1 protects yeast cells from ethanol stress by reducing intracellular ROS levels. When the MPR1 gene was overexpressed in antioxidant enzyme-deficient mutants, increased resistance to H{sub 2}O{sub 2} or heat shock was observed in cells lacking the CTA1, CTT1, or GPX1 gene encoding catalase A, catalase T, or glutathione peroxidase, respectively. These results suggest that Mpr1 might compensate the function of enzymes that detoxify H{sub 2}O{sub 2}. Hence, Mpr1 has promising potential for the breeding of novel ethanol-tolerant yeast strains. (orig.)

  8. Transcriptomics comparison between porcine adipose and bone marrow mesenchymal stem cells during in vitro osteogenic and adipogenic differentiation.

    Directory of Open Access Journals (Sweden)

    Elisa Monaco

    Full Text Available Bone-marrow mesenchymal stem cells (BMSC are considered the gold standard for use in tissue regeneration among mesenchymal stem cells (MSC. The abundance and ease of harvest make the adipose-derived stem cells (ASC an attractive alternative to BMSC. The aim of the present study was to compare the transcriptome of ASC and BMSC, respectively isolated from subcutaneous adipose tissue and femur of 3 adult pigs, during in vitro osteogenic and adipogenic differentiation for up to four weeks. At 0, 2, 7, and 21 days of differentiation RNA was extracted for microarray analysis. A False Discovery Rate ≤0.05 for overall interactions effect and P<0.001 between comparisons were used to determine differentially expressed genes (DEG. Ingenuity Pathway Analysis and DAVID performed the functional analysis of the DEG. Functional analysis of highest expressed genes in MSC and genes more expressed in MSC vs. fully differentiated tissues indicated low immunity and high angiogenic capacity. Only 64 genes were differentially expressed between ASC and BMSC before differentiation. The functional analysis uncovered a potential larger angiogenic, osteogenic, migration, and neurogenic capacity in BMSC and myogenic capacity in ASC. Less than 200 DEG were uncovered between ASC and BMSC during differentiation. Functional analysis also revealed an overall greater lipid metabolism in ASC, while BMSC had a greater cell growth and proliferation. The time course transcriptomic comparison between differentiation types uncovered <500 DEG necessary to determine cell fate. The functional analysis indicated that osteogenesis had a larger cell proliferation and cytoskeleton organization with a crucial role of G-proteins. Adipogenesis was driven by PPAR signaling and had greater angiogenesis, lipid metabolism, migration, and tumorigenesis capacity. Overall the data indicated that the transcriptome of the two MSC is relatively similar across the conditions studied. In addition

  9. HDAC-regulated myomiRs control BAF60 variant exchange and direct the functional phenotype of fibro-adipogenic progenitors in dystrophic muscles

    Science.gov (United States)

    Saccone, Valentina; Consalvi, Silvia; Giordani, Lorenzo; Mozzetta, Chiara; Barozzi, Iros; Sandoná, Martina; Ryan, Tammy; Rojas-Muñoz, Agustin; Madaro, Luca; Fasanaro, Pasquale; Borsellino, Giovanna; De Bardi, Marco; Frigè, Gianmaria; Termanini, Alberto; Sun, Xin; Rossant, Janet; Bruneau, Benoit G.; Mercola, Mark; Minucci, Saverio; Puri, Pier Lorenzo

    2014-01-01

    Fibro-adipogenic progenitors (FAPs) are important components of the skeletal muscle regenerative environment. Whether FAPs support muscle regeneration or promote fibro-adipogenic degeneration is emerging as a key determinant in the pathogenesis of muscular diseases, including Duchenne muscular dystrophy (DMD). However, the molecular mechanism that controls FAP lineage commitment and activity is currently unknown. We show here that an HDAC–myomiR–BAF60 variant network regulates the fate of FAPs in dystrophic muscles of mdx mice. Combinatorial analysis of gene expression microarray, genome-wide chromatin remodeling by nuclease accessibility (NA) combined with next-generation sequencing (NA-seq), small RNA sequencing (RNA-seq), and microRNA (miR) high-throughput screening (HTS) against SWI/SNF BAF60 variants revealed that HDAC inhibitors (HDACis) derepress a “latent” myogenic program in FAPs from dystrophic muscles at early stages of disease. Specifically, HDAC inhibition induces two core components of the myogenic transcriptional machinery, MYOD and BAF60C, and up-regulates the myogenic miRs (myomiRs) (miR-1.2, miR-133, and miR-206), which target the alternative BAF60 variants BAF60A and BAF60B, ultimately directing promyogenic differentiation while suppressing the fibro-adipogenic phenotype. In contrast, FAPs from late stage dystrophic muscles are resistant to HDACi-induced chromatin remodeling at myogenic loci and fail to activate the promyogenic phenotype. These results reveal a previously unappreciated disease stage-specific bipotency of mesenchimal cells within the regenerative environment of dystrophic muscles. Resolution of such bipotency by epigenetic intervention with HDACis provides a molecular rationale for the in situ reprogramming of target cells to promote therapeutic regeneration of dystrophic muscles. PMID:24682306

  10. Effect of Dy3+ on osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells and adipocytic trans-differentiation of mouse primary osteoblasts

    Institute of Scientific and Technical Information of China (English)

    ZHANG dinChao; LIU DanDan; SUN ding; ZHANG DaWei; SHEN ShiGang; YANG MengSu

    2009-01-01

    A series of experimental methods including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bro-mide (MTT) test,alkaline phosphatase (ALP) activity measurement,mineralized function,Oil Red O stain and measurement were employed to assess the effect of Dy3+ on the osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells (BMSCs) and the adipogenic trans-differ-entiation of mouse primary osteoblasts (Obs).The results showed that Dy3+ had no effect on BMSC proliferation at concentrations of 1×10-8 and 1×10-5 mol/L,but inhibited BMSC proliferation at other concentrations.Dy3+ had no effect on OB proliferation at concentrations of 1×10-10 and 1×10-9 mol/L,but inhibited OB proliferation at other concentrations.Dy3+ had no effect on the osteogenic differentia-tion of BMSCs at concentrations of 1×10-9 and 1×10-7 mol/L,and promoted osteogenic differentiation of BMSCs at other concentrations at the 7th day.The osteogenic differentiation of BMSCs was inhibited by Dy3+ at concentration of 1×10-5 mol/L at the 14th day,but promoted osteogenic differentiation of BMSCs at concentrations of 1×10-9,1×10-8,1×10-7 and 1×10-6 mol/L with the maximal effect at concen-tration of 10-6 mol/L.Dy3+ promoted mineralized function of BMSCs at any concentration.Dy3+ had no effect on adipogenic differentiation of BMSCs at concentration of 1×10-7 mol/L,but inhibited adipogenic differentiation of BMSCs at other concentrations.Dy3+ inhibited adipocytic trans-differentiation of Obs at any concentration,suggesting that Dy3+ had protective effect on bone and the protective effect on bone may be mediated by modulating differentiation of BMSCs away from the adipocyte and inhibiting adipocytic trans-differentiation of Obs which may promote differentiation and mineralization of Obs.These results may be valuable for better understanding the mechanism of the effect of Dy3+ on pathogenesis of osteoporosis.

  11. [Clinical relevance of N-acetyltransferase type 2 (NAT2) genetic polymorphism].

    Science.gov (United States)

    Furet, Y; Bechtel, Y; Le Guellec, C; Bechtel, P R; Autret-Leca, E; Paintaud, G

    2002-01-01

    Polymorphic N-acetyltransferase (NAT2) is involved in the metabolism of several compounds relevant in pharmacology or toxicology, with diverse clinical consequences. Inter-ethnic variations in distribution of the acetylation phenotype are significant. The caffeine test is most often used to assess the acetylation phenotype and to identify rapid and slow acetylators. The NAT2 phenotype could account for the increased risk of certain side effects in slow acetylators treated with isoniazid (particularly peripheral neuropathies and lupus erythematosus), although therapeutic efficacy seems to be independent of the acetylation status. Hypersensibility reactions with sulfonamides (including Lyell and Stevens-Johnson syndromes) are more frequent in slow acetylators, who also show poor tolerance to sulfasalazine and dapsone. In contrast, myelotoxicity induced by amonafide is more frequent in rapid acetylators, probably because of increased production of a toxic metabolite of the drug. In carcinogenesis, NAT2 may play a protective role against bladder cancer, although studies have shown contradictory results. Slow acetylators may have a risk of developing primitive liver cancer. For lung cancer, data are not conclusive, but slow acetylation status may predispose to mesothelioma in subjects exposed to asbestos. No relation has been found between acetylation phenotype and breast cancer. Contradictory results were reported on its role in colorectal cancer. Non-smoking type 1 diabetics may be at increased risk of nephropathy if they are rapid acetylators. Parkinson's disease may be more frequent among slow acetylators, but again, data have shown contradictory results. Finally, a poor acetylator phenotype may predispose to atopic diseases. PMID:12611196

  12. The Spt-Ada-Gcn5 Acetyltransferase (SAGA complex in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Paraskevi Georgakopoulos

    Full Text Available A mutation screen in Aspergillus nidulans uncovered mutations in the acdX gene that led to altered repression by acetate, but not by glucose. AcdX of A. nidulans is highly conserved with Spt8p of Saccharomyces cerevisiae, and since Spt8p is a component of the Spt-Ada-Gcn5 Acetyltransferase (SAGA complex, the SAGA complex may have a role in acetate repression in A. nidulans. We used a bioinformatic approach to identify genes encoding most members of the SAGA complex in A. nidulans, and a proteomic analysis to confirm that most protein components identified indeed exist as a complex in A. nidulans. No apparent compositional differences were detected in mycelia cultured in acetate compared to glucose medium. The methods used revealed apparent differences between Yeast and A. nidulans in the deubiquitination (DUB module of the complex, which in S. cerevisiae consists of Sgf11p, Sus1p, and Ubp8p. Although a convincing homologue of S. cerevisiae Ubp8p was identified in the A. nidulans genome, there were no apparent homologues for Sus1p and Sgf11p. In addition, when the SAGA complex was purified from A. nidulans, members of the DUB module were not co-purified with the complex, indicating that functional homologues of Sus1p and Sgf11p were not part of the complex. Thus, deubiquitination of H2B-Ub in stress conditions is likely to be regulated differently in A. nidulans compared to S. cerevisiae.

  13. Arylamine N-acetyltransferase 2 (NAT2 genetic diversity and traditional subsistence: a worldwide population survey.

    Directory of Open Access Journals (Sweden)

    Audrey Sabbagh

    Full Text Available Arylamine N-acetyltransferase 2 (NAT2 is involved in human physiological responses to a variety of xenobiotic compounds, including common therapeutic drugs and exogenous chemicals present in the diet and the environment. Many questions remain about the evolutionary mechanisms that have led to the high prevalence of slow acetylators in the human species. Evidence from recent surveys of NAT2 gene variation suggests that NAT2 slow-causing variants might have become targets of positive selection as a consequence of the shift in modes of subsistence and lifestyle in human populations in the last 10,000 years. We aimed to test more extensively the hypothesis that slow acetylation prevalence in humans is related to the subsistence strategy adopted by the past populations. To this end, published frequency data on the most relevant genetic variants of NAT2 were collected from 128 population samples (14,679 individuals representing different subsistence modes and dietary habits, allowing a thorough analysis at both a worldwide and continent scale. A significantly higher prevalence of the slow acetylation phenotype was observed in populations practicing farming (45.4% and herding (48.2% as compared to populations mostly relying on hunting and gathering (22.4% (P = 0.0007. This was closely mirrored by the frequency of the slow 590A variant that was found to occur at a three-fold higher frequency in food producers (25% as compared to hunter-gatherers (8%. These findings are consistent with the hypothesis that the Neolithic transition to subsistence economies based on agricultural and pastoral resources modified the selective regime affecting the NAT2 acetylation pathway. Furthermore, the vast amount of data collected enabled us to provide a comprehensive and up-to-date description of NAT2 worldwide genetic diversity, thus building up a useful resource of frequency data for further studies interested in epidemiological or anthropological research

  14. N-acetyltransferase 1 in colon and rectal cancer cases from an industrialized area.

    Science.gov (United States)

    Roemer, Hermann C; Weistenhofer, Wobbeke; Lohlein, Dietrich; Geller, Frank; Blomeke, Brunhilde; Golka, Klaus

    2008-01-01

    Colon and rectal cancers are both associated with genetic as well as nutritional, occupational, and environmental factors. Aromatic amines and heterocyclic amines are established colorectal carcinogens. The polymorphic enzyme N-acetyltransferase 1 (NAT1) contributes to heterocyclic amine metabolism in the human colon. Thereby, NAT1 may influence the risk for development of colorectal cancer. The distribution of NAT1 genotypes was determined in 107 colon cancer cases, 77 rectal cancer cases, and 185 controls (suffering from nonmalignant diseases) by standard methods. In addition, possible occupational and nonoccupational risk factors were determined by a personal interview. Cancer cases and controls were derived from an area of former coal, iron, and steel industries, which is known for elevated colon cancer mortality. The proportions of NAT1*4/*4 genotype were 72% in controls, 75% in rectal cancer cases, and 72% in colon cancer cases. The proportions of the NAT1*4/*10 genotype were 17.8% in controls, 12.9% in rectal cancer cases, and 14% in colon cancer cases. Combinations of the determined NAT1 alleles *3/*3, *3/*10, *4/*3, *4/*11, *10/*10 and *11/*11 contributed to 10.2% of the genotypes in controls, 12.1% in rectal cancer cases, and 14% in colon cancer cases. In contrast to another study on healthy German volunteers, the NAT1*4/*4 genotype (wild type) is overrepresented. This might be due to the variation in the proportion of NAT1 alleles in the general population. The present study does not support a relevant impact of the NAT1 genotype on colorectal cancer risk development in the study area.

  15. Garcinol, a Histone Acetyltransferase Inhibitor, Radiosensitizes Cancer Cells by Inhibiting Non-Homologous End Joining

    Energy Technology Data Exchange (ETDEWEB)

    Oike, Takahiro [Division of Multistep Carcinogenesis, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma (Japan); Ogiwara, Hideaki [Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Torikai, Kohta [Gunma University Heavy Ion Medical Center, Maebashi, Gunma (Japan); Nakano, Takashi [Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma (Japan); Yokota, Jun [Division of Multistep Carcinogenesis, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Kohno, Takashi, E-mail: tkkohno@ncc.go.jp [Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)

    2012-11-01

    Purpose: Non-homologous end joining (NHEJ), a major pathway used to repair DNA double-strand breaks (DSBs) generated by ionizing radiation (IR), requires chromatin remodeling at DSB sites through the acetylation of histones by histone acetyltransferases (HATs). However, the effect of compounds with HAT inhibitory activities on the DNA damage response (DDR), including the NHEJ and cell cycle checkpoint, as well as on the radiosensitivity of cancer cells, remains largely unclear. Here, we investigated whether garcinol, a HAT inhibitor found in the rinds of Garcinia indica fruit (called mangosteens), has effects on DDR, and whether it can be used for radiosensitization. Methods and Materials: The following assays were used to examine the effect of garcinol on the inhibition of DSB repair, including the following: a conventional neutral comet assay; a cell-based assay recently developed by us, in which NHEJ repair of DSBs on chromosomal DNA was evaluated; the micrococcal nuclease sensitivity assay; and immunoblotting for autophosphorylation of DNA-dependent protein kinase catalytic subunit (DNA-PKcs). We assessed the effect of garcinol on the cell cycle checkpoint after IR treatment by analyzing the phosphorylation levels of checkpoint kinases CHK1 and CHK2 and histone H3, and by cell cycle profile analysis using flow cytometry. The radiosensitizing effect of garcinol was assessed by a clonogenic survival assay, whereas its effects on apoptosis and senescence were examined by annexin V and senescence-associated {beta}-galactosidase (SA-{beta}-Gal) staining, respectively. Results: We found that garcinol inhibits DSB repair, including NHEJ, without affecting cell cycle checkpoint. Garcinol radiosensitized A549 lung and HeLa cervical carcinoma cells with dose enhancement ratios (at 10% surviving fraction) of 1.6 and 1.5, respectively. Cellular senescence induced by IR was enhanced by garcinol. Conclusion: These results suggest that garcinol is a radiosensitizer that

  16. N-Acetyltransferase 2 gene polymorphism in a group of senile dementia patients in Shanghai suburb

    Institute of Scientific and Technical Information of China (English)

    Wei-chao GUO; Guo-fang LIN; Yong-lin ZHA; Ke-jian LOU; Qing-wen MA; Jian-hua SHEN

    2004-01-01

    AIM: To investigate the possible association of hereditary polymorphism of N-acetyltransferase 2 (NAT2) gene with the susceptibility towards senile dementia in farmer population of Shanghai suburb. METHODS: NAT2 gene genotyping was performed at 7 major polymorphic loci (G191A, C282T, T341C, C481T, G590A, A803G, and .G857A) with a polymerase chain reaction-based restriction fragment length polymorphism based procedure in 2 groups of farmer subjects in Shanghai suburb. A group of 51 diagnosed dementia patients [comprising 29 sporadic Alzheimer disease(AD) patients and 22 sporadic vascular dementia (VD) patients] and a group of 112 healthy individuals were in the same area. RESULTS: The homogenous rapid genotypes (R/R, including*4/*4, *13/*13, and *4/*13) was found over-present in both groups of patients, compared with healthy individuals, for all farmer dementia patients, 52.9 %vs 33.0 %, P=0.016, OR (95 % CI): 2.28(1.16-4.48); for AD group only, 51.7 % vs 33.0 %, P=0.063, OR (95 %CI): 2.18 (0.95-4.97); for VD group 54.5 % vs 33.0 %, P=0.055, OR (95 % CI): 2.43 (0.96-2.43). The significant frequency difference of genotype *4/* 7B between farmer dementia patients and healthy individuals, and that of solo-alleles *13, and *7B were observed between the healthy individuals and both groups of dementia patients.CONCLUSION: Our data suggest the involvement of various NAT2 rapid-acetylating genotypes in the individual susceptibility to senile dementia. Variant genotypes of NAT2 might serve as a hereditary risk factor for AD and VD in Chinese population.

  17. Benzodiazepines: rat pinealocyte binding sites and augmentation of norepinephrine-stimulated N-acetyltransferase activity

    Energy Technology Data Exchange (ETDEWEB)

    Matthew, E.; Parfitt, A.G.; Sugden, D.; Engelhardt, D.L.; Zimmerman, E.A.; Klein, D.C.

    1984-02-01

    Studies of (/sup 3/H)diazepam binding to intact rat pineal cells were carried out in tissue culture preparations. The binding was saturable, reversible and proportional to the number of cells used. Scatchard analysis resulted in a linear plot (Kd . 23 nM, maximum binding sites (Bmax) . 1.56 pmol/mg of protein for cells in monolayer culture; Kd . 7 nM, Bmax . 1.3 pmol/mg of protein for cells in suspension culture). Inhibition constants (Ki) for clonazepam (500 nM), flunitrazepam (38 nM) and Ro-5-4864 (5 nM) indicated that the binding sites were probably of the ''peripheral'' type. In addition, the effects of diazepam on norepinephrine-stimulated N-acetyltransferase (NAT) activity were studied in organ culture and dissociated cell culture. Diazepam (10-50 microM) both prolonged and increased the magnitude of the norepinephrine-induced increase in NAT activity but did not affect the initial rate of rise of enzyme activity. The effect was dose-dependent and was also seen with clonazepam, flunitrazepam and Ro-5-4864, but not with Ro-15-1788. Diazepam, by itself, at these concentrations, had no effect on NAT, but enzyme activity was increased by higher concentrations (0.1-1 mM). Although a relationship between the (/sup 3/H)diazepam binding sites described here and the effect of benzodiazepines on NAT cannot be established from these studies, the data suggest that the benzodiazepines may alter melatonin levels through their action on NAT.

  18. Benzodiazepines: rat pinealocyte binding sites and augmentation of norepinephrine-stimulated N-acetyltransferase activity

    International Nuclear Information System (INIS)

    Studies of [3H]diazepam binding to intact rat pineal cells were carried out in tissue culture preparations. The binding was saturable, reversible and proportional to the number of cells used. Scatchard analysis resulted in a linear plot [Kd . 23 nM, maximum binding sites (Bmax) . 1.56 pmol/mg of protein for cells in monolayer culture; Kd . 7 nM, Bmax . 1.3 pmol/mg of protein for cells in suspension culture]. Inhibition constants (Ki) for clonazepam (500 nM), flunitrazepam (38 nM) and Ro-5-4864 (5 nM) indicated that the binding sites were probably of the ''peripheral'' type. In addition, the effects of diazepam on norepinephrine-stimulated N-acetyltransferase (NAT) activity were studied in organ culture and dissociated cell culture. Diazepam (10-50 microM) both prolonged and increased the magnitude of the norepinephrine-induced increase in NAT activity but did not affect the initial rate of rise of enzyme activity. The effect was dose-dependent and was also seen with clonazepam, flunitrazepam and Ro-5-4864, but not with Ro-15-1788. Diazepam, by itself, at these concentrations, had no effect on NAT, but enzyme activity was increased by higher concentrations (0.1-1 mM). Although a relationship between the [3H]diazepam binding sites described here and the effect of benzodiazepines on NAT cannot be established from these studies, the data suggest that the benzodiazepines may alter melatonin levels through their action on NAT

  19. N-Acetyltransferase 2 genetic polymorphisms and risk of colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Tiago Donizetti da Silva; Aledson Vitor Felipe; Jacqueline Miranda de Lima; Celina Tizuko Fujiyama Oshima; Nora Manoukian Forones

    2011-01-01

    AIM: To investigate the possible association between meat intake, cigarette smoking and N-acetyltransferase 2 (NAT2) genetic polymorphisms on colorectal cancer (CRC) risk.METHODS: Patients with CRC were matched for gender and age to healthy controls. Meat intake and cigarette smoking were assessed using a specific frequency questionnaire. DNA was extracted from peripheral blood and the genotypes of the polymorphism were assessed by polymerase chain reaction-restriction fragment length polymorphism. Five NAT2 alleles were studied (WT, M1,M2, M3 and M4) using specific digestion enzymes.RESULTS: A total of 147 patients with colorectal cancer (76 women and 90 men with colon cancer) and 212 controls were studied. The mean age of the two groups was 62 years. More than half the subjects (59.8% in the case group and 51.9% in the control group) were NAT2 slow acetylators. The odds ratio for colorectal cancer was 1.38 (95% CI: 0.90-2.12) in slow acetylators. Although the number of women was small (n = 76 in the case group),the cancer risk was found to be lower in intermediate (W/Mx) acetylators [odds ratio (OR): 0.55, 95% confidence interval (95% CI): 0.29-1.02]. This difference was not observed in men (OR: 0.56, 95% CI: 0.16-2.00). Among NAT2 fast acetylators (W/W or W/Mx), meat consumption more than 3 times a week increased the risk of colorectal cancer (OR: 2.05, 95% CI: 1.01-4.16). In contrast,cigarette smoking increased the risk of CRC among slow acetylators (OR: 1.97, 95% CI: 1.02-3.79).CONCLUSION: The risk of CRC was higher among fast acetylators who reported a higher meat intake. Slow NAT2 acetylation was associated with an increased risk of CRC.

  20. Garcinol, a Histone Acetyltransferase Inhibitor, Radiosensitizes Cancer Cells by Inhibiting Non-Homologous End Joining

    International Nuclear Information System (INIS)

    Purpose: Non-homologous end joining (NHEJ), a major pathway used to repair DNA double-strand breaks (DSBs) generated by ionizing radiation (IR), requires chromatin remodeling at DSB sites through the acetylation of histones by histone acetyltransferases (HATs). However, the effect of compounds with HAT inhibitory activities on the DNA damage response (DDR), including the NHEJ and cell cycle checkpoint, as well as on the radiosensitivity of cancer cells, remains largely unclear. Here, we investigated whether garcinol, a HAT inhibitor found in the rinds of Garcinia indica fruit (called mangosteens), has effects on DDR, and whether it can be used for radiosensitization. Methods and Materials: The following assays were used to examine the effect of garcinol on the inhibition of DSB repair, including the following: a conventional neutral comet assay; a cell-based assay recently developed by us, in which NHEJ repair of DSBs on chromosomal DNA was evaluated; the micrococcal nuclease sensitivity assay; and immunoblotting for autophosphorylation of DNA-dependent protein kinase catalytic subunit (DNA-PKcs). We assessed the effect of garcinol on the cell cycle checkpoint after IR treatment by analyzing the phosphorylation levels of checkpoint kinases CHK1 and CHK2 and histone H3, and by cell cycle profile analysis using flow cytometry. The radiosensitizing effect of garcinol was assessed by a clonogenic survival assay, whereas its effects on apoptosis and senescence were examined by annexin V and senescence-associated β-galactosidase (SA-β-Gal) staining, respectively. Results: We found that garcinol inhibits DSB repair, including NHEJ, without affecting cell cycle checkpoint. Garcinol radiosensitized A549 lung and HeLa cervical carcinoma cells with dose enhancement ratios (at 10% surviving fraction) of 1.6 and 1.5, respectively. Cellular senescence induced by IR was enhanced by garcinol. Conclusion: These results suggest that garcinol is a radiosensitizer that inhibits NHEJ

  1. Histone acetyltransferase GCN5 interferes with the miRNA pathway in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Wanhui Kim; Moussa Benhamed; Caroline Servet; David Latrasse; Wei Zhang; Marianne Delarue; Dao-Xiu Zhou

    2009-01-01

    MicroRNAs (miRNA) that guide sequence-specific posttranscriptional gene silencing play an important role in gene expression required for both developmental processes and responses to environmental conditions in plants. However, little is known about the transcriptional and posttranscriptional regulation of miRNA expression. Histone acetylation plays an important role in chromatin remodeling and is required for gene activation. By analyzing the accumulation of subset of miRNAs and the corresponding primary miRNAs in mutants of Arabidopsis, we show that histone acetyltransferase GCN5 (General control non-repressed protein5) has a general repressive effect on miRNA production, while it is required for the expression of a subset of (e.g. stress-inducible) MIRNA genes. The general negative function of GCN5 in miRNA production is likely achieved through an indirect repression of the miRNA ma-chinery genes such as DICER LIKE1 (DCLI), SERRATE (SE), HYPONASTIC LEAVES1 (HYL1) and ARGONAUTE1(AGOI). Chromatin immunoprecipitation assays revealed that GCN5 targets to a subset of MIRNA genes and is required for acetylation of histone H3 lysine 14 at these loci. Moreover, inhibition of histone deacetylation by trichos-tatin A treatment or in histone deacetylase gene mutants impaired the accumulation of certain miRNAs. These data together suggest that Arabidopsis GCN5 interferes with the miRNA pathway at both the transcriptional and post-transcriptional levels and histone acetylation/deacetylation is an epigenetic mechanism involved in the regulation of miRNA production.

  2. N-acetyltransferase 2, exposure to aromatic and heterocyclic amines, and receptor-defined breast cancer.

    Science.gov (United States)

    Rabstein, Sylvia; Brüning, Thomas; Harth, Volker; Fischer, Hans-Peter; Haas, Susanne; Weiss, Tobias; Spickenheuer, Anne; Pierl, Christiane; Justenhoven, Christina; Illig, Thomas; Vollmert, Caren; Baisch, Christian; Ko, Yon-Dschun; Hamann, Ute; Brauch, Hiltrud; Pesch, Beate

    2010-03-01

    The role of N-acetyltransferase 2 (NAT2) polymorphism in breast cancer is still unclear. We explored the associations between potential sources of exposure to aromatic and heterocyclic amines (AHA), acetylation status and receptor-defined breast cancer in 1020 incident cases and 1047 population controls of the German GENICA study. Acetylation status was assessed as slow or fast. Therefore, NAT2 haplotypes were estimated using genotype information from six NAT2 polymorphisms. Most probable haplotypes served as alleles for the deduction of NAT2 acetylation status. The risks of developing estrogen receptor alpha (ER) and progesterone receptor (PR)-positive or negative tumors were estimated for tobacco smoking, consumption of red meat, grilled food, coffee, and tea, as well as expert-rated occupational exposure to AHA with logistic regression conditional on age and adjusted for potential confounders. Joint effects of these factors and NAT2 acetylation status were investigated. Frequent consumption of grilled food and coffee showed higher risks in slow acetylators for receptor-negative tumors [grilled food: ER-: odds ratio (OR) 2.57, 95% confidence interval (CI) 1.07-6.14 for regular vs. rare; coffee: ER-: OR 2.55, 95% CI 1.22-5.33 for >or=4 vs. 0 cups/day]. We observed slightly higher risks for never smokers that are fast acetylators for receptor-positive tumors compared with slow acetylators (ER-: OR 1.32, 95% CI 1.00-1.73). Our results support differing risk patterns for receptor-defined breast cancer. However, the modifying role of NAT2 for receptor-defined breast cancer is difficult to interpret in the light of complex mixtures of exposure to AHA. PMID:19996973

  3. Estrogen intervention in microvascular morphology and choline acetyltransferase expression in rat hippocampal neurons in chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Zhenjun Yang; Hongwei Yan; Guomin Zhang; Zhihong Chen; Jingfeng Xue

    2011-01-01

    We observed dynamic changes in microvessels and a protective effect of estrogen on chronic cerebral ischemia ovariectomized rat models established through permanent occlusion of bilateral carotid arteries at 7, 14 and 21 days. The results revealed that estrogen improved microvasculature in the hippocampus of chronic cerebral ischemic rats, upregulated Bcl-2 protein expression, downregulated Bax protein expression, increased choline acetyltransferase expression in hippocampal cholinergic neurons, and suppressed hippocampal neuronal apoptosis. These findings indicate that estrogen can protect hippocampal neurons in rats with chronic cerebral ischemia.

  4. RKIP phosphorylation-dependent ERK1 activation stimulates adipogenic lipid accumulation in 3T3-L1 preadipocytes overexpressing LC3.

    Science.gov (United States)

    Hahm, Jong Ryeal; Ahmed, Mahmoud; Kim, Deok Ryong

    2016-09-01

    3T3-L1 preadipocytes undergo adipogenesis in response to treatment with dexamethaxone, 1-methyl-3-isobutylxanthine, and insulin (DMI) through activation of several adipogenic transcription factors. Many autophagy-related proteins are also highly activated in the earlier stages of adipogenesis, and the LC3 conjugation system is required for formation of lipid droplets. Here, we investigated the effect of overexpression of green fluorescent protein (GFP)-LC3 fusion protein on adipogenesis. Overexpression of GFP-LC3 in 3T3-L1 preadipocytes using poly-l-lysine-assisted adenoviral GFP-LC3 transduction was sufficient to produce intracellular lipid droplets. Indeed, GFP-LC3 overexpression stimulated expression of some adipogenic transcription factors (e.g., C/EBPα or β, PPARγ, SREBP2). In particular, SREBP2 was highly activated in preadipocytes transfected with adenoviral GFP-LC3. Also, phosphorylation of Raf kinase inhibitory protein (RKIP) at serine 153, consequently stimulating extracellular-signal regulated kinase (ERK)1 activity, was significantly increased during adipogenesis induced by either poly-l-lysine-assisted adenoviral GFP-LC3 transduction or culture in the presence of dexamethasone, 1-methyl-3-isobutylxanthine, and insulin. Furthermore, RKIP knockdown promoted ERK1 and PPARγ activation, and significantly increased the intracellular accumulation of triacylglycerides in DMI-induced adipogenesis. In conclusion, GFP-LC3 overexpression in 3T3-L1 preadipocytes stimulates adipocyte differentiation via direct modulation of RKIP-dependent ERK1 activity.

  5. Inhibition of Lysine-Specific Demethylase-1 (LSD1/KDM1A) Promotes the Adipogenic Differentiation of hESCs Through H3K4 Methylation.

    Science.gov (United States)

    Xiong, Yujing; Wang, Enyin; Huang, Yan; Guo, Xiaoyi; Yu, Yiping; Du, Qingyun; Ding, Xiaoyan; Sun, Yingpu

    2016-06-01

    Given their totipotency, human embryonic stem cells (hESCs) can differentiate into all types of cells, including adipocytes, and provide an excellent research model for studying diseases associated with the metabolism of adipocytes, such as obesity and diabetes mellitus. Epigenetic regulation, including DNA methylation and histone modification, plays an essential role in the development and differentiation of hESCs. Lysine-specific demethylase 1 (LSD1), a well-characterized histone-modifying enzyme, demethylates dimethylated histone H3 lysine 4 (H3K4) through a flavin adenine dinucleotide (FAD)-dependent oxidative reaction. LSD1 affects the growth and differentiation of human and mouse ES cells, and the deletion of this gene in mice leads to embryonic lethality. Here, we investigated the functional role of LSD1 during the adipogenic differentiation of hESCs involving the demethylation of H3K4. We also found that treating hESCs with the LSD1 inhibitor CBB1007 promotes the adipogenic differentiation of hESCs. PMID:27059868

  6. Effects of gentamicin on choline acetyltransferase expression in paraolivary nucleus neurons of guinea pigs

    Institute of Scientific and Technical Information of China (English)

    Mingguang Zhao; Xiaochen Wang; Yong Liang; Peng Xie; Xuejun Guo; Jinjiang Li; Wei Wang

    2008-01-01

    BACKGROUND: It is generally accepted that gentamicin can damage the cochlear nerve and acoustic nerve. In recent years, scholars have focused on neuronal changes and neurochemical information in the brainstem primary auditory center. OBJECTIVE: To explore morphological changes of choline acetyltransferase (ChAT)-positive neurons in the paraolivary nucleus (PON) of guinea pigs, and the effect on hearing following gentamicin injection. DESIGN, TIME AND SETTING: Randomized grouping and morphological observational study was performed at Animal Experimental Center of General Hospital of Shenyang Military Area Command of Chinese PLA from January to August 2007. MATERIALS: A total of 48 healthy guinea pigs were randomly divided into model (n = 40) and control (n = 8) groups. The model group was divided into five subgroups at five time points of I and 3 days, 1, 2, and 3 weeks. METHODS: Guinea pigs in the model group were intraperitoneally injected with gentamicin, and those in the control group were intraperitoneally injected with the same volume of saline. MAIN OUTCOME MEASURES: Auditory brainstem-evoked potential was used to record auditory threshold; distribution and morphological changes of ChAT-positive neurons in the PON were observed with immunohistochemistry; section area and gray value of ChAT-positive neurons were measured with Quantimet 570 image-analyzing system. RESULTS: ChAT-positive neurons were diffusedly distributed in the PON. The majority was composed of large, round cells, with positive neurites that could be clearly observed. Following gentamicin injection, the positive neurons displayed an irregular outline, and their neurites began to shorten and disappear. The gray value increased with prolonged gentamicin administration (P < 0.05). In addition, the somatic cross-sectional area was enlarged in the model group at 1 and 3 days after injection (P < 0.05), whereas cell number significantly decreased at three weeks after injection (P < 0.05). Starting

  7. Plasmodium falciparum Histone Acetyltransferase, a Yeast GCN5 Homologue Involved in Chromatin Remodeling

    Institute of Scientific and Technical Information of China (English)

    QiFan; LijiaAn; LiwangCui

    2005-01-01

    The yeast transcriptional coactivator GCN5 (yGCN5), a histone acetyltransferase (HAT), is part of large multimeric complexes that are required for chromatin remodeling and transcriptional activation. Like other eukaryotes, the malaria parasite DNA is organized into nucleosomes and the genome encodes components of chromatin-remodeling complexes. Here we show that GCN5 is conserved in Plasmodium species and that the most homologous regions are within the HAT domain and the bromodomain. The Plasmodiumfalclparum GCN5 homologue (PfGCN5) is spliced with three introns, encoding a protein of 1,464 residues. Mapping of the ends of the PfGCN5 transcript suggests that the mRNA is 5.2 to 5.4 kb, consistent with the result from Northern analysis. Using free core histones, we determined that recombinant PfGCN5 proteins have conserved HAT activity with a substrate preference for histone H3. Using substrate-specific antibodies, we determined that both Lys-8 and -14 of H3 were acetylated by the recombinant PfGCN5. In eukaryotes, GCN5 homologues interact with yeast ADA2 homologues and form large multiprotein HAT complexes. We have identified an ADA2 homologue in P. falciparum, PfADA2. Yeast two-hybrid and in vitro binding assays verified the interactions between PfGCN5 and PfADA2, suggesting that they may be associated with each other in vivo. The conserved function of the HAT domain in PfGCN5 was further illustrated with yeast complementation experiments, which showed that the PfGCN5 region corresponding to the full-length yGCN5 could partially complement the yGCN5 deletion mutation. Furthermore, a chimera comprising the PfGCN5 HAT domain fused to the remainder of yeast GCN5 (yGCN5) fully rescued the yGCN5 deletion mutant. These data demonstrate that PfGCN5 is an authentic GCN5 family member and may exist in chromatin-remodeling complexes to regulate gene expression in P. falciparum.

  8. Facilitated interaction between the pyruvate dehydrogenase kinase isoform 2 and the dihydrolipoyl acetyltransferase.

    Science.gov (United States)

    Hiromasa, Yasuaki; Roche, Thomas E

    2003-09-01

    The dihydrolipoyl acetyltransferase (E2) has an enormous impact on pyruvate dehydrogenase kinase (PDK) phosphorylation of the pyruvate dehydrogenase (E1) component by acting as a mobile binding framework and in facilitating and mediating regulation of PDK activity. Analytical ultracentrifugation (AUC) studies established that the soluble PDK2 isoform is a stable dimer. The interaction of PDK2 with the lipoyl domains of E2 (L1, L2) and the E3-binding protein (L3) were characterized by AUC. PDK2 interacted very weakly with L2 (Kd approximately 175 microM for 2 L2/PDK2) but much tighter with dimeric glutathione S-transferase (GST)-L2 (Kd approximately 3 microM), supporting the importance of bifunctional binding. Reduction of lipoyl groups resulted in approximately 8-fold tighter binding of PDK2 to GST-L2red, which was approximately 300-fold tighter than binding of 2 L2red and also much tighter than binding by GST-L1red and GST-L3red. The E2 60-mer bound approximately 18 PDK2 dimers with a Kd similar to GST-L2. E2.E1 bound more PDK2 (approximately 27.6) than E2 with approximately 2-fold tighter affinity. Lipoate reduction fostered somewhat tighter binding at more sites by E2 and severalfold tighter binding at the majority of sites on E2.E1. ATP and ADP decreased the affinity of PDK2 for E2 by 3-5-fold and adenosine 5'-(beta,gamma-imino)triphosphate or phosphorylation of E1 similarly reduced PDK2 binding to E2.E1. Reversible bifunctional binding to L2 with the mandatory singly held transition fits the proposed "hand-over-hand" movement of a kinase dimer to access E1 without dissociating from the complex. The gain in binding interactions upon lipoate reduction likely aids reduction-engendered stimulation of PDK2 activity; loosening of binding as a result of adenine nucleotides and phosphorylation may instigate movement of lipoyl domain-held kinase to a new E1 substrate. PMID:12816949

  9. Choline acetyltransferase expressed by radial neuroglia cells in the development of telencephalon: A validated study

    Institute of Scientific and Technical Information of China (English)

    Li Zhou; Lingling Ding; Zhisuo Xiao; Yuanyuan Qin; Guibin Li

    2007-01-01

    BACKGROUND: Cholinergic neuron directly participants in human motion, learning and memory and is a target cell for multiple degenerative diseases of central nervous system.OBJECTIVE: To investigate whether the mitotic cell is the radial glial cell expressing choline acetyltransferase (ChAT) in ventricle zone (VZ) of telencephalon and whether cholinergic neuron is derived from radial glial cell in ventricle zone of telencephalon.DESIGN: Observational study.SETTING: Department of Histology and Embryology, Basic Medical College of Jilin University.MATERIALS: Nine healthy Wistar rats included 6 females and 3 male. Male and female rats were mated routinely, and the day when spermatozoa or vaginal plug were found was regarded as embryonic 0 (E0).Primary monoclonal antibodies ChAT and vimentin were provided respectively by Wuhan Boster Company,and Biogenex Company, USA.METHODS: The experiment was carried out in the Laboratory of Cell Culture and Immunohistochemistry,Department of Histology and Embryology from march 2002 to January 2003. Firstly, fluorescence-activated cell sorting (FACS) was used to confirm the time of generation of cholinergic neuron; secondly,telencephalons of rats at embryonic 14 days (E14) were performed coronary sections, then immunohistochemistry double staining for vimentin (a protein marker of radial neuroglia cell) and ChAT (a protein marker of cholinergic neuron) were used to test whether ChAT was expressed in the radial neuroglia cells.results of immunohistochemistry double staining.RESULTS: It is confirmed using by flow cytometer that embryogenesis time of cholinergic neuron was at E12, and shown the population of cells in VZ of dorsal telencephalon of E14 rat co-expressed vimentin and ChAT through immunohistochemistry double staining. A lot of vimentin-positive cells and ChAT-positive cells respectively were observed in VZ of lateral ganglionic eminence.CONCLUSION: Cholinergic neuron in cerebral cortex is derived from radial glial cells in VZ

  10. N-acetylglucosamine sensing by a GCN5-related N-acetyltransferase induces transcription via chromatin histone acetylation in fungi

    Science.gov (United States)

    Su, Chang; Lu, Yang; Liu, Haoping

    2016-01-01

    N-acetylglucosamine (GlcNAc) exists ubiquitously as a component of the surface on a wide range of cells, from bacteria to humans. Many fungi are able to utilize environmental GlcNAc to support growth and induce cellular development, a property important for their survival in various host niches. However, how the GlcNAc signal is sensed and subsequently transduced is largely unknown. Here, we identify a gene that is essential for GlcNAc signalling (NGS1) in Candida albicans, a commensal and pathogenic yeast of humans. Ngs1 can bind GlcNAc through the N-terminal β-N-acetylglucosaminidase homology domain. This binding activates N-acetyltransferase activity in the C-terminal GCN5-related N-acetyltransferase domain, which is required for GlcNAc-induced promoter histone acetylation and transcription. Ngs1 is targeted to the promoters of GlcNAc-inducible genes constitutively by the transcription factor Rep1. Ngs1 is conserved in diverse fungi that have GlcNAc catabolic genes. Thus, fungi use Ngs1 as a GlcNAc-sensor and transducer for GlcNAc-induced transcription. PMID:27694804

  11. Biochemical evidence for relaxed substrate specificity of Nα-acetyltransferase (Rv3420c/rimI) of Mycobacterium tuberculosis

    Science.gov (United States)

    Pathak, Deepika; Bhat, Aadil Hussain; Sapehia, Vandana; Rai, Jagdish; Rao, Alka

    2016-01-01

    Nα-acetylation is a naturally occurring irreversible modification of N-termini of proteins catalyzed by Nα-acetyltransferases (NATs). Although present in all three domains of life, it is little understood in bacteria. The functional grouping of NATs into six types NatA - NatF, in eukaryotes is based on subunit requirements and stringent substrate specificities. Bacterial orthologs are phylogenetically divergent from eukaryotic NATs, and only a couple of them are characterized biochemically. Accordingly, not much is known about their substrate specificities. Rv3420c of Mycobacterium tuberculosis is a NAT ortholog coding for RimIMtb. Using in vitro peptide-based enzyme assays and mass-spectrometry methods, we provide evidence that RimIMtb is a protein Nα-acetyltransferase of relaxed substrate specificity mimicking substrate specificities of eukaryotic NatA, NatC and most competently that of NatE. Also, hitherto unknown acetylation of residues namely, Asp, Glu, Tyr and Leu by a bacterial NAT (RimIMtb) is elucidated, in vitro. Based on in vivo acetylation status, in vitro assay results and genetic context, a plausible cellular substrate for RimIMtb is proposed. PMID:27353550

  12. The human serotonin N-acetyltransferase (EC 2.3.1.87) gene (AANAT): Structure, chromosomal localization, and tissue expression

    Energy Technology Data Exchange (ETDEWEB)

    Coon, S.L.; Bernard, M.; Roseboom, P.H. [National Institutes of Health, Bethesda, MD (United States)] [and others

    1996-05-15

    Serotonin N-acetyltransferase (arylalkylamine N-acetyltransferase, AA-NAT, HGMW-approved symbol AANAT;EC 2.3.1.87) is the penultimate enzyme in melatonin synthesis and controls the night/day rhythm in melatonin production in the vertebrate pineal gland. We have found that the human AA-NAT gene spans {approx}2.5 kb, contains four exons, and is located at chromosome 17q25. The open reading frame encodes a 23.2-kDa protein that is {approx}80% identical to sheep and rat AA-NAT. The AA-NAT transcript ({approx}1 kb) is highly abundant in the pineal gland and is expressed at lower levels in the retina and in the Y79 retinoblastoma cell line. AA-NAT mRNA is also detectable at low levels in several brain regions and the pituitary gland, but not in several peripheral tissues examined. Brain and pituitary AA-NAT could modulate serotonin-dependent aspects of human behavior and pituitary function. 31 refs., 5 figs.

  13. Polymorphisms in the Human Cytochrome P450 and Arylamine N-Acetyltransferase: Susceptibility to Head and Neck Cancers

    Directory of Open Access Journals (Sweden)

    Rim Khlifi

    2013-01-01

    Full Text Available The occurrence of head and neck cancer (HNC is associated with smoking and alcohol drinking. Tobacco smoking exposes smokers to a series of carcinogenic chemicals. Cytochrome P450 enzymes (CYP450s, such as CYP1A1, CYP1B1, and CYP2D6, usually metabolize carcinogens to their inactive derivatives, but they occasionally convert the chemicals to more potent carcinogens. In addition, via CYP450 (CYP2E1 oxidase, alcohol is metabolized to acetaldehyde, a highly toxic compound, which plays an important role in carcinogenesis. Furthermore, two N-acetyltransferase isozymes (NATs, NAT1 and NAT2, are polymorphic and catalyze both N-acetylation and O-acetylation of aromatic and heterocyclic amine carcinogens. Genetic polymorphisms are associated with a number of enzymes involved in the metabolism of carcinogens important in the induction of HNC. It has been suggested that such polymorphisms may be linked to cancer susceptibility. In this paper, we select four cytochrome P450 enzymes (CYP1A1, CYP1BA1, CYP2D6, and CYP2E1, and two N-acetyltransferase isozymes (NAT1 and NAT2 in order to summarize and analyze findings from the literature related to HNC risk by focusing on (i the interaction between these genes and the environment, (ii the impact of genetic defect on protein activity and/or expression, and (iii the eventual involvement of race in such associations.

  14. The UmGcn5 gene encoding histone acetyltransferase from Ustilago maydis is involved in dimorphism and virulence.

    Science.gov (United States)

    González-Prieto, Juan Manuel; Rosas-Quijano, Raymundo; Domínguez, Angel; Ruiz-Herrera, José

    2014-10-01

    We isolated a gene encoding a histone acetyltransferase from Ustilago maydis (DC.) Cda., which is orthologous to the Saccharomyces cerevisiae GCN5 gene. The gene was isolated from genomic clones identified by their specific hybridization to a gene fragment obtained by the polymerase chain reaction (PCR). This gene (Umgcn5; um05168) contains an open reading frame (ORF) of 1421bp that encodes a putative protein of 473 amino acids with a Mr. of 52.6kDa. The protein exhibits a high degree of homology with histone acetyltransferases from different organisms. Null a2b2 ΔUmgcn5 mutants were constructed by substitution of the region encoding the catalytic site with a hygromycin B resistance cassette. Null a1b1 ΔUmgcn5 mutants were isolated from genetic crosses of a2b2 ΔUmgcn5 and a1b1 wild-type strains in maize. Mutants displayed a slight reduction in growth rate under different conditions, and were more sensitive than the wild type to stress conditions, but more important, they grew as long mycelial cells, and formed fuzz-like colonies under all conditions where wild-type strains grew in the yeast-like morphology and formed smooth colonies. This phenotype was not reverted by cAMP addition. Mutants were not virulent to maize plants, and were unable to form teliospores. These phenotypic alterations of the mutants were reverted by their transformation with the wild-type gene.

  15. Cloning and analysis of a Toxoplasma gondii histone acetyltransferase: a novel chromatin remodelling factor in Apicomplexan parasites.

    Science.gov (United States)

    Hettmann, C; Soldati, D

    1999-11-15

    The yeast transcriptional adaptor GCN5 functions as a histone acetyltransferase, directly linking chromatin modification to transcriptional regulation. Homologues of yeast GCN5 have been found in Tetrahymena, Drosophila, Arabidopsis and human, suggesting that this pathway of chromatin remodelling is evolutionarily conserved. Consistent with this view, we have identified the Toxoplasma gondii homologue, referred to here as TgGCN5. The gene codes for a protein of 474 amino acids with an estimated molecular mass of 53 kDa. The protein reveals two regions of close similarity with the GCN5 family members, the HAT domain and the bromodomain. Tg GCN5 occurs in a single copy in the T.gondii genome. The introduction of a second copy of TgGCN5 in T.gondii tachyzoites is toxic unless the HAT activity is disrupted by a single point mutation. Full TgGCN5 does not complement the growth defect in a yeast gcn5 (-)mutant strain, but a chimera comprising the T.gondii HAT domain fused to the remainder of yGCN5 does. These data show that T.gondii GNC5 is a histone acetyltransferase attesting to the significance of chromatin remodelling in gene regulation of Apicomplexa.

  16. Patterns of Direct Projections from the Hippocampus to the Medial Septum-Diagonal Band Complex : Anterograde Tracing with Phaseolus vulgaris Leucoagglutinin Combined with Immunohistochemistry of Choline Acetyltransferase

    NARCIS (Netherlands)

    Gaykema, R.P.A.; Kuil, J. van der; Hersh, L.B.; Luiten, P.G.M.

    1991-01-01

    The projections from the Ammon's horn to the cholinergic cell groups in the medial septal and diagonal band nuclei were investigated with anterograde tracing of Phaseolus vulgaris leucoagglutinin combined with immunocytochemical detection of choline acetyltransferase, in the rat. Tracer injections w

  17. Urinary acetylated metabolites and N-acetyltransferase-2 genotype in human subjects treated with a para-phenylenediamine-containing oxidative hair dye

    NARCIS (Netherlands)

    Nohynek, G.J.; Skare, J.A.; Meuling, W.J.A.; Hein, D.W.; Bie, A.T.H.J. de; Toutain, H.

    2004-01-01

    In the organism of mammals, important detoxification pathways of arylamines are catalysed by N-acetyltransferase 2 (NAT2). A recent case-control epidemiology study suggested that human NAT2 slow acetylators exposed to oxidative hair dyes may be at greater risk to develop bladder cancer. We therefore

  18. Effects of chronic renal failure rat serum on histone acetyltransferase p300 and activation of activating transcription factor 4 of arterial smooth muscle cells cultured in vitro

    Institute of Scientific and Technical Information of China (English)

    张耀全

    2014-01-01

    Objective To investigate the effects of the rat serum with chronic renal failure(CRF)on ubiquitin-proteasome pathway,histone acetyltransferase p300 and activation of activating transcription factor 4(ATF4)of rat arterial vascular smooth muscle cells(VSMCs)cultured in vitro,and explore the possible mechanism.Methods Objective To establish the rat model of

  19. Dehydrodiconiferyl alcohol isolated from Cucurbita moschata shows anti-adipogenic and anti-lipogenic effects in 3T3-L1 cells and primary mouse embryonic fibroblasts.

    Science.gov (United States)

    Lee, Junghun; Kim, Donghyun; Choi, Jonghyun; Choi, Hyounjeong; Ryu, Jae-Ha; Jeong, Jinhyun; Park, Eun-Jin; Kim, Seon-Hee; Kim, Sunyoung

    2012-03-16

    A water-soluble extract from the stems of Cucurbita moschata, code named PG105, was previously found to contain strong anti-obesity activities in a high fat diet-induced obesity mouse model. One of its biological characteristics is that it inhibits 3T3-L1 adipocyte differentiation. To isolate the biologically active compound(s), conventional solvent fractionation was performed, and the various fractions were tested for anti-adipogenic activity using Oil Red O staining method. A single spot on thin layer chromatography of the chloroform fraction showed a potent anti-adipogenic activity. When purified, the structure of its major component was resolved as dehydrodiconiferyl alcohol (DHCA), a lignan, by NMR and mass spectrometry analysis. In 3T3-L1 cells, synthesized DHCA significantly reduced the expression of several adipocyte marker genes, including peroxisome proliferator-activated receptor γ (Pparg), CCAAT/enhancer-binding protein α (Cebpa), fatty acid-binding protein 4 (Fabp4), sterol response element-binding protein-1c (Srebp1c), and stearoyl-coenzyme A desaturase-1 (Scd), and decreased lipid accumulation without affecting cell viability. DHCA also suppressed the mitotic clonal expansion of preadipocytes (an early event of adipogenesis), probably by suppressing the DNA binding activity of C/EBPβ, and lowered the production level of cyclinA and cyclin-dependent kinase 2 (Cdk2), coinciding with the decrease in DNA synthesis and cell division. In addition, DHCA directly inhibited the expression of SREBP-1c and SCD-1. Similar observations were made, using primary mouse embryonic fibroblasts. Taken together, our data indicate that DHCA may contain dual activities, affecting both adipogenesis and lipogenesis.

  20. Extraction of Flavonoids from the Flowers of Abelmoschus manihot (L. Medic by Modified Supercritical CO2 Extraction and Determination of Antioxidant and Anti-Adipogenic Activity

    Directory of Open Access Journals (Sweden)

    Jingjing Li

    2016-06-01

    Full Text Available Abelmoschus manihot (L. Medic has been used for many years in Chinese traditional medicine. In this study, supercritical CO2 plus a modifier was utilized to extract flavonoids from the flowers of Abelmoschus manihot (L. Medic. The effects of temperature (40 °C–60 °C, pressure (10–30 MPa and different concentrations of ethanol as modifier (60%–90%, ethanol:water, v/v on major flavonol content and the antioxidant activity of the extracts were studied by response surface methodology (RSM using a Box-Behnken design. The flavonol content was calculated as the sum of the concentrations of seven major flavonoids, namely rutin, hyperin, isoquercetin, hibifolin, myricetin, quercetin-3′-O-glucoside and quercetin, which were simultaneously determined by a HPLC method. The antioxidant activity was evaluated by a 2,2-diphenyl-1-picrylhydarzyl (DPPH free radical-scavenging assay. The results showed that three factors and their interactions could be well fitted to second-order polynomial models (p < 0.05. At the optimal extraction conditions for flavonol content (20 MPa, 52 °C, and 85% ethanol content, the yield of flavonoids was 41.96 mg/g and the IC50 value was 0.288 mg/mL, respectively, suggesting the extract has high antioxidant activity. Furthermore, the anti-adipogenic activity of the extract on the 3T3-L1 cell line was investigated. The results indicated that it can downregulate PPARγ and C/EBPα expression at mRNA. In summary, in this study, we have established a cost-effective method for the extraction of flavonoids from the flowers of Abelmoschus manihot (L. Medic using supercritical fluid extraction and the extracts exhibited potent antioxidant and anti-adipogenic effects, suggesting a possible therapeutic approach for the prevention and treatment of obesity.

  1. Effect of decellularized adipose tissue particle size and cell density on adipose-derived stem cell proliferation and adipogenic differentiation in composite methacrylated chondroitin sulphate hydrogels.

    Science.gov (United States)

    Brown, Cody F C; Yan, Jing; Han, Tim Tian Y; Marecak, Dale M; Amsden, Brian G; Flynn, Lauren E

    2015-08-01

    An injectable composite scaffold incorporating decellularized adipose tissue (DAT) as a bioactive matrix within a hydrogel phase capable of in situ polymerization would be advantageous for adipose-derived stem cell (ASC) delivery in the filling of small or irregular soft tissue defects. Building on previous work, the current study investigates DAT milling methods and the effects of DAT particle size and cell seeding density on the response of human ASCs encapsulated in photo-cross-linkable methacrylated chondroitin sulphate (MCS)-DAT composite hydrogels. DAT particles were generated by milling lyophilized DAT and the particle size was controlled through the processing conditions with the goal of developing composite scaffolds with a tissue-specific 3D microenvironment tuned to enhance adipogenesis. ASC proliferation and adipogenic differentiation were assessed in vitro in scaffolds incorporating small (average diameter of 38   ±   6 μm) or large (average diameter of 278   ±   3 μm) DAT particles in comparison to MCS controls over a period of up to 21 d. Adipogenic differentiation was enhanced in the composites incorporating the smaller DAT particles and seeded at the higher density of 5   ×   10(5) ASCs/scaffold, as measured by glycerol-3-phosphate dehydrogenase (GPDH) enzyme activity, semi-quantitative analysis of perilipin expression and oil red O staining of intracellular lipid accumulation. Overall, this study demonstrates that decellularized tissue particle size can impact stem cell differentiation through cell-cell and cell-matrix interactions, providing relevant insight towards the rational design of composite biomaterial scaffolds for adipose tissue engineering. PMID:26225549

  2. Effect of decellularized adipose tissue particle size and cell density on adipose-derived stem cell proliferation and adipogenic differentiation in composite methacrylated chondroitin sulphate hydrogels.

    Science.gov (United States)

    Brown, Cody F C; Yan, Jing; Han, Tim Tian Y; Marecak, Dale M; Amsden, Brian G; Flynn, Lauren E

    2015-07-30

    An injectable composite scaffold incorporating decellularized adipose tissue (DAT) as a bioactive matrix within a hydrogel phase capable of in situ polymerization would be advantageous for adipose-derived stem cell (ASC) delivery in the filling of small or irregular soft tissue defects. Building on previous work, the current study investigates DAT milling methods and the effects of DAT particle size and cell seeding density on the response of human ASCs encapsulated in photo-cross-linkable methacrylated chondroitin sulphate (MCS)-DAT composite hydrogels. DAT particles were generated by milling lyophilized DAT and the particle size was controlled through the processing conditions with the goal of developing composite scaffolds with a tissue-specific 3D microenvironment tuned to enhance adipogenesis. ASC proliferation and adipogenic differentiation were assessed in vitro in scaffolds incorporating small (average diameter of 38   ±   6 μm) or large (average diameter of 278   ±   3 μm) DAT particles in comparison to MCS controls over a period of up to 21 d. Adipogenic differentiation was enhanced in the composites incorporating the smaller DAT particles and seeded at the higher density of 5   ×   10(5) ASCs/scaffold, as measured by glycerol-3-phosphate dehydrogenase (GPDH) enzyme activity, semi-quantitative analysis of perilipin expression and oil red O staining of intracellular lipid accumulation. Overall, this study demonstrates that decellularized tissue particle size can impact stem cell differentiation through cell-cell and cell-matrix interactions, providing relevant insight towards the rational design of composite biomaterial scaffolds for adipose tissue engineering.

  3. Extraction of Flavonoids from the Flowers of Abelmoschus manihot (L.) Medic by Modified Supercritical CO₂ Extraction and Determination of Antioxidant and Anti-Adipogenic Activity.

    Science.gov (United States)

    Li, Jingjing; Zhang, Juan; Wang, Min

    2016-01-01

    Abelmoschus manihot (L.) Medic has been used for many years in Chinese traditional medicine. In this study, supercritical CO₂ plus a modifier was utilized to extract flavonoids from the flowers of Abelmoschus manihot (L.) Medic. The effects of temperature (40 °C-60 °C), pressure (10-30 MPa) and different concentrations of ethanol as modifier (60%-90%, ethanol:water, v/v) on major flavonol content and the antioxidant activity of the extracts were studied by response surface methodology (RSM) using a Box-Behnken design. The flavonol content was calculated as the sum of the concentrations of seven major flavonoids, namely rutin, hyperin, isoquercetin, hibifolin, myricetin, quercetin-3'-O-glucoside and quercetin, which were simultaneously determined by a HPLC method. The antioxidant activity was evaluated by a 2,2-diphenyl-1-picrylhydarzyl (DPPH) free radical-scavenging assay. The results showed that three factors and their interactions could be well fitted to second-order polynomial models (p extraction conditions for flavonol content (20 MPa, 52 °C, and 85% ethanol content), the yield of flavonoids was 41.96 mg/g and the IC50 value was 0.288 mg/mL, respectively, suggesting the extract has high antioxidant activity. Furthermore, the anti-adipogenic activity of the extract on the 3T3-L1 cell line was investigated. The results indicated that it can downregulate PPARγ and C/EBPα expression at mRNA. In summary, in this study, we have established a cost-effective method for the extraction of flavonoids from the flowers of Abelmoschus manihot (L.) Medic using supercritical fluid extraction and the extracts exhibited potent antioxidant and anti-adipogenic effects, suggesting a possible therapeutic approach for the prevention and treatment of obesity. PMID:27347916

  4. Caveolin-1, Caveolin-2 and Cavin-1 are strong predictors of adipogenic differentiation in human tumors and cell lines of liposarcoma.

    Science.gov (United States)

    Codenotti, Silvia; Vezzoli, Marika; Poliani, Pietro Luigi; Cominelli, Manuela; Bono, Federica; Kabbout, Hadi; Faggi, Fiorella; Chiarelli, Nicola; Colombi, Marina; Zanella, Isabella; Biasiotto, Giorgio; Montanelli, Alessandro; Caimi, Luigi; Monti, Eugenio; Fanzani, Alessandro

    2016-08-01

    Caveolins (Cav-1, -2 and -3) and Cavins (Cavin-1, -2, -3 and -4) are two protein families controlling the biogenesis and function of caveolae, plasma membrane omega-like invaginations representing the primary site of important cellular processes like endocytosis, cholesterol homeostasis and signal transduction. Caveolae are especially abundant in fat tissue, playing a consistent role in a number of processes, such as the insulin-dependent glucose uptake and transmembrane transport of lipids underlying differentiation, maintenance and adaptive hypertrophy of adipocytes. Based on this premise, in this work we have investigated the expression of caveolar protein components in liposarcoma (LPS), an adipocytic soft tissue sarcoma affecting adults categorized in well-differentiated, dedifferentiated, myxoid and pleomorphic histotypes. By performing an extensive microarray data analysis followed by immunohistochemistry on human LPS tumors, we demonstrated that Cav-1, Cav-2 and Cavin-1 always cluster in all the histotypes, reaching the highest expression in well-differentiated LPS, the least aggressive of the malignant forms composed by tumor cells with a morphology resembling mature adipocytes. In vitro experiments carried out using two human LPS cell lines showed that the expression levels of Cav-1, Cav-2 and Cavin-1 proteins were faintly detectable during cell growth, becoming consistently increased during the accumulation of intracellular lipid droplets characterizing the adipogenic differentiation. Moreover, in differentiated LPS cells the three proteins were also found to co-localize and form molecular aggregates at the plasma membrane, as shown via immunofluorescence and immunoprecipitation analysis. Overall, these data indicate that Cav-1, Cav-2 and Cavin-1 may be considered as reliable markers for identification of LPS tumors characterized by consistent adipogenic differentiation. PMID:27168348

  5. The ATM-related domain of TRRAP is required for histone acetyltransferase recruitment and Myc-dependent oncogenesis

    Science.gov (United States)

    Park, Jeonghyeon; Kunjibettu, Sudeesha; McMahon, Steven B.; Cole, Michael D.

    2001-01-01

    The ATM-related TRRAP protein is a component of several different histone acetyltransferase (HAT) complexes but lacks the kinase activity characteristic of other ATM family members. We identified a novel function for this evolutionarily conserved domain in its requirement for the assembly of a functional HAT complex. Ectopic expression of TRRAP protein with a mutation in the ATM-related domain inhibits Myc-mediated oncogenic transformation. The Myc-binding region of TRRAP maps to a separable domain, and ectopic expression of this domain inhibits cell growth. These findings demonstrate that the ATM-related domain of TRRAP forms a structural core for the assembly and recruitment of HAT complexes by transcriptional activators. PMID:11445536

  6. Genetic variants in microsomal epoxide hydrolase and N-acetyltransferase 2 in susceptibility of IBD in the Danish population

    DEFF Research Database (Denmark)

    Ernst, Anja; Andersen, Vibeke; Østergaard, Mette;

    Introduction. Inflammatory bowel disease (IBD) is characterised by recurrent inflammation of the intestinal mucosa, however the exact mechanism is unknown. Reactive molecules play a central role in the disruption of the mucosa increasing the permeability across the intestinal barrier, which may...... induce or sustain an immune response. Changes in detoxification of substances that causes epithelial damage may confer susceptibility to IBD. Hence, polymorphic enzymes involved in the detoxification processes may be risk factors of IBD. Methods. The two biotransformation enzymes microsomal epoxide......-acetyltransferase 2 acetylator status and IBD. An association between high activity of microsomal epoxide hydrolase and disease diagnosis before age 40 in CD with an OR of 2.2(1.1- 4.2) P=0.02) was found. No other phenotypic associations were found for the two enzymes and IBD, regarding age at onset, disease location...

  7. Single neuron transcriptomics identify SRSF/SR protein B52 as a regulator of axon growth and Choline acetyltransferase splicing

    Science.gov (United States)

    Liu, Boyin; Bossing, Torsten

    2016-01-01

    We removed single identified neurons from living Drosophila embryos to gain insight into the transcriptional control of developing neuronal networks. The microarray analysis of the transcriptome of two sibling neurons revealed seven differentially expressed transcripts between both neurons (threshold: log21.4). One transcript encodes the RNA splicing factor B52. Loss of B52 increases growth of axon branches. B52 function is also required for Choline acetyltransferase (ChAT ) splicing. At the end of embryogenesis, loss of B52 function impedes splicing of ChAT, reduces acetylcholine synthesis, and extends the period of uncoordinated muscle twitches during larval hatching. ChAT regulation by SRSF proteins may be a conserved feature since changes in SRSF5 expression and increased acetylcholine levels in brains of bipolar disease patients have been reported recently. PMID:27725692

  8. Mutation of the CH1 Domain in the Histone Acetyltransferase CREBBP Results in Autism-Relevant Behaviors in Mice.

    Science.gov (United States)

    Zheng, Fei; Kasper, Lawryn H; Bedford, David C; Lerach, Stephanie; Teubner, Brett J W; Brindle, Paul K

    2016-01-01

    Autism spectrum disorders (ASDs) are a group of neurodevelopmental afflictions characterized by repetitive behaviors, deficits in social interaction, and impaired communication skills. For most ASD patients, the underlying causes are unknown. Genetic mutations have been identified in about 25 percent of ASD cases, including mutations in epigenetic regulators, suggesting that dysregulated chromatin or DNA function is a critical component of ASD. Mutations in the histone acetyltransferase CREB binding protein (CBP, CREBBP) cause Rubinstein-Taybi Syndrome (RTS), a developmental disorder that includes ASD-like symptoms. Recently, genomic studies involving large numbers of ASD patient families have theoretically modeled CBP and its paralog p300 (EP300) as critical hubs in ASD-associated protein and gene interaction networks, and have identified de novo missense mutations in highly conserved residues of the CBP acetyltransferase and CH1 domains. Here we provide animal model evidence that supports this notion that CBP and its CH1 domain are relevant to autism. We show that mice with a deletion mutation in the CBP CH1 (TAZ1) domain (CBPΔCH1/ΔCH1) have an RTS-like phenotype that includes ASD-relevant repetitive behaviors, hyperactivity, social interaction deficits, motor dysfunction, impaired recognition memory, and abnormal synaptic plasticity. Our results therefore indicate that loss of CBP CH1 domain function contributes to RTS, and possibly ASD, and that this domain plays an essential role in normal motor function, cognition and social behavior. Although the key physiological functions affected by ASD-associated mutation of epigenetic regulators have been enigmatic, our findings are consistent with theoretical models involving CBP and p300 in ASD, and with a causative role for recently described ASD-associated CBP mutations.

  9. Mutation of the CH1 Domain in the Histone Acetyltransferase CREBBP Results in Autism-Relevant Behaviors in Mice.

    Directory of Open Access Journals (Sweden)

    Fei Zheng

    Full Text Available Autism spectrum disorders (ASDs are a group of neurodevelopmental afflictions characterized by repetitive behaviors, deficits in social interaction, and impaired communication skills. For most ASD patients, the underlying causes are unknown. Genetic mutations have been identified in about 25 percent of ASD cases, including mutations in epigenetic regulators, suggesting that dysregulated chromatin or DNA function is a critical component of ASD. Mutations in the histone acetyltransferase CREB binding protein (CBP, CREBBP cause Rubinstein-Taybi Syndrome (RTS, a developmental disorder that includes ASD-like symptoms. Recently, genomic studies involving large numbers of ASD patient families have theoretically modeled CBP and its paralog p300 (EP300 as critical hubs in ASD-associated protein and gene interaction networks, and have identified de novo missense mutations in highly conserved residues of the CBP acetyltransferase and CH1 domains. Here we provide animal model evidence that supports this notion that CBP and its CH1 domain are relevant to autism. We show that mice with a deletion mutation in the CBP CH1 (TAZ1 domain (CBPΔCH1/ΔCH1 have an RTS-like phenotype that includes ASD-relevant repetitive behaviors, hyperactivity, social interaction deficits, motor dysfunction, impaired recognition memory, and abnormal synaptic plasticity. Our results therefore indicate that loss of CBP CH1 domain function contributes to RTS, and possibly ASD, and that this domain plays an essential role in normal motor function, cognition and social behavior. Although the key physiological functions affected by ASD-associated mutation of epigenetic regulators have been enigmatic, our findings are consistent with theoretical models involving CBP and p300 in ASD, and with a causative role for recently described ASD-associated CBP mutations.

  10. Mutation of the CH1 Domain in the Histone Acetyltransferase CREBBP Results in Autism-Relevant Behaviors in Mice.

    Science.gov (United States)

    Zheng, Fei; Kasper, Lawryn H; Bedford, David C; Lerach, Stephanie; Teubner, Brett J W; Brindle, Paul K

    2016-01-01

    Autism spectrum disorders (ASDs) are a group of neurodevelopmental afflictions characterized by repetitive behaviors, deficits in social interaction, and impaired communication skills. For most ASD patients, the underlying causes are unknown. Genetic mutations have been identified in about 25 percent of ASD cases, including mutations in epigenetic regulators, suggesting that dysregulated chromatin or DNA function is a critical component of ASD. Mutations in the histone acetyltransferase CREB binding protein (CBP, CREBBP) cause Rubinstein-Taybi Syndrome (RTS), a developmental disorder that includes ASD-like symptoms. Recently, genomic studies involving large numbers of ASD patient families have theoretically modeled CBP and its paralog p300 (EP300) as critical hubs in ASD-associated protein and gene interaction networks, and have identified de novo missense mutations in highly conserved residues of the CBP acetyltransferase and CH1 domains. Here we provide animal model evidence that supports this notion that CBP and its CH1 domain are relevant to autism. We show that mice with a deletion mutation in the CBP CH1 (TAZ1) domain (CBPΔCH1/ΔCH1) have an RTS-like phenotype that includes ASD-relevant repetitive behaviors, hyperactivity, social interaction deficits, motor dysfunction, impaired recognition memory, and abnormal synaptic plasticity. Our results therefore indicate that loss of CBP CH1 domain function contributes to RTS, and possibly ASD, and that this domain plays an essential role in normal motor function, cognition and social behavior. Although the key physiological functions affected by ASD-associated mutation of epigenetic regulators have been enigmatic, our findings are consistent with theoretical models involving CBP and p300 in ASD, and with a causative role for recently described ASD-associated CBP mutations. PMID:26730956

  11. Choline acetyltransferase and organic cation transporters are responsible for synthesis and propionate-induced release of acetylcholine in colon epithelium.

    Science.gov (United States)

    Bader, Sandra; Klein, Jochen; Diener, Martin

    2014-06-15

    Acetylcholine is not only a neurotransmitter, but is found in a variety of non-neuronal cells. For example, the enzyme choline acetyltransferase (ChAT), catalyzing acetylcholine synthesis, is expressed by the colonic epithelium of different species. These cells release acetylcholine across the basolateral membrane after luminal exposure to propionate, a short-chain fatty acid. The functional consequence is the induction of chloride secretion, measurable as increase in short-circuit current (Isc) in Ussing chamber experiments. It is unclear how acetylcholine is produced and released by colonic epithelium. Therefore, the aim of the present study was the identification (on mRNA and protein level) and functional characterization (in Ussing chamber experiments combined with HPLC detection of acetylcholine) of transporters/enzymes in the cholinergic system of rat colonic epithelium. Immunohistochemical staining as well as RT-PCR revealed the expression of high-affinity choline transporter, ChAT, carnitine acetyltransferase (CarAT), vesicular acetylcholine transporter (VAChT), and organic cation transporters (OCT 1, 2, 3) in colonic epithelium. In contrast to blockade of ChAT with bromoacetylcholine, inhibition of CarAT with mildronate did not inhibit the propionate-induced increase in Isc, suggesting a predominant synthesis of epithelial acetylcholine by ChAT. Although being expressed, blockade of VAChT with vesamicol was ineffective, whereas inhibition of OCTs with omeprazole and corticosterone inhibited propionate-induced Isc and the release of acetylcholine into the basolateral compartment. In summary, OCTs seem to be involved in regulated acetylcholine release by colonic epithelium, which is assumed to be involved in chemosensing of luminal short-chain fatty acids by the intestinal epithelium.

  12. Dissecting the Molecular Roles of Histone Chaperones in Histone Acetylation by Type B Histone Acetyltransferases (HAT-B).

    Science.gov (United States)

    Haigney, Allison; Ricketts, M Daniel; Marmorstein, Ronen

    2015-12-18

    The HAT-B enzyme complex is responsible for acetylating newly synthesized histone H4 on lysines K5 and K12. HAT-B is a multisubunit complex composed of the histone acetyltransferase 1 (Hat1) catalytic subunit and the Hat2 (rbap46) histone chaperone. Hat1 is predominantly localized in the nucleus as a member of a trimeric NuB4 complex containing Hat1, Hat2, and a histone H3-H4 specific histone chaperone called Hif1 (NASP). In addition to Hif1 and Hat2, Hat1 interacts with Asf1 (anti-silencing function 1), a histone chaperone that has been reported to be involved in both replication-dependent and -independent chromatin assembly. To elucidate the molecular roles of the Hif1 and Asf1 histone chaperones in HAT-B histone binding and acetyltransferase activity, we have characterized the stoichiometry and binding mode of Hif1 and Asf1 to HAT-B and the effect of this binding on the enzymatic activity of HAT-B. We find that Hif1 and Asf1 bind through different modes and independently to HAT-B, whereby Hif1 binds directly to Hat2, and Asf1 is only capable of interactions with HAT-B through contacts with histones H3-H4. We also demonstrate that HAT-B is significantly more active against an intact H3-H4 heterodimer over a histone H4 peptide, independent of either Hif1 or Asf1 binding. Mutational studies further demonstrate that HAT-B binding to the histone tail regions is not sufficient for this enhanced activity. Based on these data, we propose a model for HAT-B/histone chaperone assembly and acetylation of H3-H4 complexes.

  13. From arylamine N-acetyltransferase to folate-dependent acetyl CoA hydrolase: impact of folic acid on the activity of (HUMAN)NAT1 and its homologue (MOUSE)NAT2.

    Science.gov (United States)

    Laurieri, Nicola; Dairou, Julien; Egleton, James E; Stanley, Lesley A; Russell, Angela J; Dupret, Jean-Marie; Sim, Edith; Rodrigues-Lima, Fernando

    2014-01-01

    Acetyl Coenzyme A-dependent N-, O- and N,O-acetylation of aromatic amines and hydrazines by arylamine N-acetyltransferases is well characterised. Here, we describe experiments demonstrating that human arylamine N-acetyltransferase Type 1 and its murine homologue (Type 2) can also catalyse the direct hydrolysis of acetyl Coenzyme A in the presence of folate. This folate-dependent activity is exclusive to these two isoforms; no acetyl Coenzyme A hydrolysis was found when murine arylamine N-acetyltransferase Type 1 or recombinant bacterial arylamine N-acetyltransferases were incubated with folate. Proton nuclear magnetic resonance spectroscopy allowed chemical modifications occurring during the catalytic reaction to be analysed in real time, revealing that the disappearance of acetyl CH3 from acetyl Coenzyme A occurred concomitantly with the appearance of a CH3 peak corresponding to that of free acetate and suggesting that folate is not acetylated during the reaction. We propose that folate is a cofactor for this reaction and suggest it as an endogenous function of this widespread enzyme. Furthermore, in silico docking of folate within the active site of human arylamine N-acetyltransferase Type 1 suggests that folate may bind at the enzyme's active site, and facilitate acetyl Coenzyme A hydrolysis. The evidence presented in this paper adds to our growing understanding of the endogenous roles of human arylamine N-acetyltransferase Type 1 and its mouse homologue and expands the catalytic repertoire of these enzymes, demonstrating that they are by no means just xenobiotic metabolising enzymes but probably also play an important role in cellular metabolism. These data, together with the characterisation of a naphthoquinone inhibitor of folate-dependent acetyl Coenzyme A hydrolysis by human arylamine N-acetyltransferase Type 1/murine arylamine N-acetyltransferase Type 2, open up a range of future avenues of exploration, both for elucidating the developmental role of these

  14. From arylamine N-acetyltransferase to folate-dependent acetyl CoA hydrolase: impact of folic acid on the activity of (HUMANNAT1 and its homologue (MOUSENAT2.

    Directory of Open Access Journals (Sweden)

    Nicola Laurieri

    Full Text Available Acetyl Coenzyme A-dependent N-, O- and N,O-acetylation of aromatic amines and hydrazines by arylamine N-acetyltransferases is well characterised. Here, we describe experiments demonstrating that human arylamine N-acetyltransferase Type 1 and its murine homologue (Type 2 can also catalyse the direct hydrolysis of acetyl Coenzyme A in the presence of folate. This folate-dependent activity is exclusive to these two isoforms; no acetyl Coenzyme A hydrolysis was found when murine arylamine N-acetyltransferase Type 1 or recombinant bacterial arylamine N-acetyltransferases were incubated with folate. Proton nuclear magnetic resonance spectroscopy allowed chemical modifications occurring during the catalytic reaction to be analysed in real time, revealing that the disappearance of acetyl CH3 from acetyl Coenzyme A occurred concomitantly with the appearance of a CH3 peak corresponding to that of free acetate and suggesting that folate is not acetylated during the reaction. We propose that folate is a cofactor for this reaction and suggest it as an endogenous function of this widespread enzyme. Furthermore, in silico docking of folate within the active site of human arylamine N-acetyltransferase Type 1 suggests that folate may bind at the enzyme's active site, and facilitate acetyl Coenzyme A hydrolysis. The evidence presented in this paper adds to our growing understanding of the endogenous roles of human arylamine N-acetyltransferase Type 1 and its mouse homologue and expands the catalytic repertoire of these enzymes, demonstrating that they are by no means just xenobiotic metabolising enzymes but probably also play an important role in cellular metabolism. These data, together with the characterisation of a naphthoquinone inhibitor of folate-dependent acetyl Coenzyme A hydrolysis by human arylamine N-acetyltransferase Type 1/murine arylamine N-acetyltransferase Type 2, open up a range of future avenues of exploration, both for elucidating the

  15. Inhibition of Viability, Proliferation, Cytokines Secretion, Surface Antigen Expression, and Adipogenic and Osteogenic Differentiation of Adipose-Derived Stem Cells by Seven-Day Exposure to 0.5 T Static Magnetic Fields

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2016-01-01

    Full Text Available After seven-day exposure to 0.5-Tesla Static Magnetic Field (SMF, Adipose-derived Stem Cells (ASCs and those labeled by superparamagnetic iron oxide (SPIO nanoparticles were examined for viability by methyl thiazol tetrazolium (MTT assay, proliferation by cell counting and bromodeoxyuridine (BrdU incorporation, DNA integrity by single cell gel electrophoresis, surface antigen by flow cytometry analysis, and the expression of cytokines and genetic markers by reverse transcription-PCR and underwent adipogenic and osteogenic differentiation assessed by quantifying related specific genes expression. The SMF slightly reduced cell viability and proliferation and inhibited the expression of CD49d, CD54, and CD73 but did not damage DNA integrity. The SMF slightly downregulated the expression of cytokines including Vascular Endothelial Growth Factor (VEGF, Insulin-like Growth Factor-1 (IGF-1, Transforming Growth Factor Beta 1 (TGF-β1, genetic markers comprising Stem Cell Antigen-1 (Sca1, Octamer-4 (Oct-4, ATP-binding Cassette Subfamily B Member 1 (ABCB1, adipogenic marker genes containing Lipoprotein Lipase (LPL, Peroxisome Proliferator-Activated Receptor Gamma (PPAR-γ, and osteogenic marker genes including Secreted Phosphor-protein 1 (SPP1 and Osterix (OSX. Exposure to 0.5 T SMF for seven days inhibited viability, proliferation, surface antigen expression, cytokine secretion, stem cell genetic marker expression, and adipogenic and osteogenic differentiation but did not affect the DNA integrity in ASCs with or without SPIO labeling.

  16. p300 exerts an epigenetic role in chronic neuropathic pain through its acetyltransferase activity in rats following chronic constriction injury (CCI

    Directory of Open Access Journals (Sweden)

    Zhu Xiao-Yan

    2012-11-01

    Full Text Available Abstract Background Neuropathic pain is detrimental to human health; however, its pathogenesis still remains largely unknown. Overexpression of pain-associated genes and increased nociceptive somato-sensitivity are well observed in neuropathic pain. The importance of epigenetic mechanisms in regulating the expression of pro- or anti-nociceptive genes has been revealed by studies recently, and we hypothesize that the transcriptional coactivator and the histone acetyltransferase E1A binding protein p300 (p300, as a part of the epigenetic mechanisms of gene regulation, may be involved in the pathogenesis of neuropathic pain induced by chronic constriction injury (CCI. To test this hypothesis, two different approaches were used in this study: (I down-regulating p300 with specific small hairpin RNA (shRNA and (II chemical inhibition of p300 acetyltransferase activity by a small molecule inhibitor, C646. Results Using the CCI rat model, we found that the p300 expression was increased in the lumbar spinal cord on day 14 after CCI. The treatment with intrathecal p300 shRNA reversed CCI-induced mechanical allodynia and thermal hyperalgesia, and suppressed the expression of cyclooxygenase-2 (COX-2, a neuropathic pain-associated factor. Furthermore, C646, an inhibitor of p300 acetyltransferase, also attenuated mechanical allodynia and thermal hyperalgesia, accompanied by a suppressed COX-2 expression, in the spinal cord. Conclusions The results suggest that, through its acetyltransferase activity in the spinal cord after CCI, p300 epigenetically plays an important role in neuropathic pain. Inhibiting p300, using interfering RNA or C646, may be a promising approach to the development of new neuropathic pain therapies.

  17. Development of highly glyphosate-tolerant tobacco by coexpression of glyphosate acetyltransferase gat and EPSPS G2-aroA genes

    OpenAIRE

    Baoqing Dun; Xujing Wang; Wei Lu; Ming Chen; Wei Zhang; Shuzhen Ping; Zhixing Wang; Baoming Zhang; Min Lin

    2014-01-01

    The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Glyphosate acetyltransferase (GAT) effectively detoxifies glyphosate by N-acetylation. With the aim of identifying a new strategy for development of glyphosate-tolerant crops, the plant expression vector pG2-GAT harboring gat and G2-aroA (encoding EPSPS) has been transformed into tobacco (Nicotiana tabacum) to develop novel plants with higher tolerance to glyphosate. Results from Southern and Wes...

  18. Repression of c-Myc and inhibition of G1 exit in cells conditionally overexpressing p300 that is not dependent on its histone acetyltransferase activity

    OpenAIRE

    Baluchamy, Sudhakar; Rajabi, Hasan N.; Thimmapaya, Rama; Navaraj, Arunasalam; Thimmapaya, Bayar

    2003-01-01

    p300 and cAMP response element binding protein (CREB)-binding protein (CBP) are two highly homologous, conserved transcriptional coactivators, and histone acetyltransferases (HATs) that link chromatin remodeling with transcription. Cell transformation by viral oncogene products such as adenovirus E1A and SV40 large T antigen depends on their ability to inactivate p300 and CBP. To investigate the role of p300 in cell-cycle progression, we constructed stable rat cell lin...

  19. Flavour formation in fungi: characterisation of KlAtf, the Kluyveromyces lactis orthologue of the Saccharomyces cerevisiae alcohol acetyltransferases Atf1 and Atf2.

    Science.gov (United States)

    Van Laere, Stijn D M; Saerens, Sofie M G; Verstrepen, Kevin J; Van Dijck, Patrick; Thevelein, Johan M; Delvaux, Freddy R

    2008-04-01

    Volatile aroma-active esters are responsible for the fruity character of fermented alcoholic beverages, such as beer and wine. In the brewers' yeast Saccharomyces cerevisiae, the major part of these esters is formed by two alcohol acetyltransferases, Atf1 and Atf2. In this paper, the existence of orthologues of these S. cerevisiae alcohol acetyltransferases in several ascomycetous fungi was investigated. Bioinformatic analysis of sequenced fungal genomes revealed the presence of multiple orthologues. The Saccharomyces sensu stricto yeasts all have two genes coding for orthologues. More distantly related fungi like Saccharomyces castelii, Candida glabrata, Kluyveromyces waltii and Kluyveromyces lactis have only one orthologue in their genome. The homology between the identified proteins and the S. cerevisiae alcohol acetyltransferases suggests a role for these orthologues in the aroma-active ester formation. To verify this, the K. lactis orthologue KlAtf was cloned and expressed in S. cerevisiae. Gas chromatographic analysis of small-scale fermentations with the transformant strains showed that, while S. cerevisiae ATF1 overexpression resulted in a substantial increase in acetate ester levels, S. cerevisiae ATF2 and K. lactis ATF overexpression only caused a moderate increase in acetate esters. This study is the first report of the presence of an ester synthesis gene in K. lactis.

  20. Structural analysis of PseH, the Campylobacter jejuni N-acetyltransferase involved in bacterial O-linked glycosylation

    Energy Technology Data Exchange (ETDEWEB)

    Song, Wan Seok; Nam, Mi Sun; Namgung, Byeol [Department of Systems Immunology, College of Biomedical Science, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Yoon, Sung-il, E-mail: sungil@kangwon.ac.kr [Department of Systems Immunology, College of Biomedical Science, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2015-03-20

    Campylobacter jejuni is a bacterium that uses flagella for motility and causes worldwide acute gastroenteritis in humans. The C. jejuni N-acetyltransferase PseH (cjPseH) is responsible for the third step in flagellin O-linked glycosylation and plays a key role in flagellar formation and motility. cjPseH transfers an acetyl group from an acetyl donor, acetyl coenzyme A (AcCoA), to the amino group of UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine to produce UDP-2,4-diacetamido-2,4,6-trideoxy-β-L-altropyranose. To elucidate the catalytic mechanism of cjPseH, crystal structures of cjPseH alone and in complex with AcCoA were determined at 1.95 Å resolution. cjPseH folds into a single-domain structure of a central β-sheet decorated by four α-helices with two continuously connected grooves. A deep groove (groove-A) accommodates the AcCoA molecule. Interestingly, the acetyl end of AcCoA points toward an open space in a neighboring shallow groove (groove-S), which is occupied by extra electron density that potentially serves as a pseudosubstrate, suggesting that the groove-S may provide a substrate-binding site. Structure-based comparative analysis suggests that cjPseH utilizes a unique catalytic mechanism of acetylation that has not been observed in other glycosylation-associated acetyltransferases. Thus, our studies on cjPseH will provide valuable information for the design of new antibiotics to treat C. jejuni-induced gastroenteritis. - Highlights: • cjPseH adopts a single-domain structure of a central β-sheet decorated by α-helices. • cjPseH features two continuously connected grooves on the protein surface. • Acetyl coenzyme A (AcCoA) binds into a deep groove of cjPseH in an ‘L’ shape. • The acetyl end of AcCoA points to a wide groove, a potential substrate-binding site.

  1. N-acetyltransferase 8, a positional candidate for blood pressure and renal regulation: resequencing, association and in silico study

    Directory of Open Access Journals (Sweden)

    Rosenberg Mai

    2008-04-01

    Full Text Available Abstract Background Kidneys have an important function in blood pressure (BP regulation and elevated BP may lead to kidney failure. Chr2p12-p13 region linked to BP traits in multiple studies harbours a potential candidate for BP and renal function, N-acetyltransferase 8 (NAT8 expressed in embryonic and adult kidney and associated with nephrotoxicity response. Methods/Results We report the first study exploring NAT8 as a potential candidate gene for blood pressure and kidney function. The resequencing (n = 42, random Estonian samples identified 15 NAT8 polymorphisms, including 6 novel variants. The diversity of NAT8 5' upstream region (π/bp = 0.00320 exceeded up to 10 times the variation in the NAT8 genic region (π/bp = 0.00037 as well as the average variation (π/bp = 0.00040 for the promoters of 29 reference genes associated with hypertension. We suggest that a potential source for such high variation could be an active gene conversion process from NAT8B duplicate gene to NAT8. Similarly to NAT8, several reference genes with the most variable upstream regions have also duplicate copies. The NAT8 promoter SNPs were targeted with pilot quantitative association studies for blood pressure (n = 137, healthy unrelated individuals and for the index of kidney function – estimated glomerular filtration rate (eGFR; n = 157 hypertensives with and without nephropathy. Minor alleles of these polymorphisms revealed a significant protective effect against elevated systolic BP as well as kidney failure in hypertension patients (p Conclusion The full resequencing and pilot association study of a novel positional candidate gene for blood pressure and renal function, human N-acetyltransferase 8, suggested a contribution of highly variable NAT8 promoter polymorphisms in determination of systolic blood pressure and eGFR. Based on in silico analysis, we raise the hypothesis that the alternative SNP alleles of the NAT8 upstream region may have differential effect

  2. Sex-biased transcription enhancement by a 5' tethered Gal4-MOF histone acetyltransferase fusion protein in Drosophila

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    Belikoff Esther J

    2010-11-01

    Full Text Available Abstract Background In male Drosophila melanogaster, the male specific lethal (MSL complex is somehow responsible for a two-fold increase in transcription of most X-linked genes, which are enriched for histone H4 acetylated at lysine 16 (H4K16ac. This acetylation requires MOF, a histone acetyltransferase that is a component of the MSL complex. MOF also associates with the non-specific lethal or NSL complex. The MSL complex is bound within active genes on the male X chromosome with a 3' bias. In contrast, the NSL complex is enriched at promoter regions of many autosomal and X-linked genes in both sexes. In this study we have investigated the role of MOF as a transcriptional activator. Results MOF was fused to the DNA binding domain of Gal4 and targeted to the promoter region of UAS-reporter genes in Drosophila. We found that expression of a UAS-red fluorescent protein (DsRed reporter gene was strongly induced by Gal4-MOF. However, DsRed RNA levels were about seven times higher in female than male larvae. Immunostaining of polytene chromosomes showed that Gal4-MOF co-localized with MSL1 to many sites on the X chromosome in male but not female nuclei. However, in female nuclei that express MSL2, Gal4-MOF co-localized with MSL1 to many sites on polytene chromosomes but DsRed expression was reduced. Mutation of conserved active site residues in MOF (Glu714 and Cys680 reduced HAT activity in vitro and UAS-DsRed activation in Drosophila. In the presence of Gal4-MOF, H4K16ac levels were enriched over UAS-lacZ and UAS-arm-lacZ reporter genes. The latter utilizes the constitutive promoter from the arm gene to drive lacZ expression. In contrast to the strong induction of UAS-DsRed expression, UAS-arm-lacZ expression increased by about 2-fold in both sexes. Conclusions Targeting MOF to reporter genes led to transcription enhancement and acetylation of histone H4 at lysine 16. Histone acetyltransferase activity was required for the full transcriptional

  3. Adipogenic placenta-derived mesenchymal stem cells are not lineage restricted by withdrawing extrinsic factors: developing a novel visual angle in stem cell biology

    Science.gov (United States)

    Hu, C; Cao, H; Pan, X; Li, J; He, J; Pan, Q; Xin, J; Yu, X; Li, J; Wang, Y; Zhu, D; Li, L

    2016-01-01

    Current evidence implies that differentiated bone marrow mesenchymal stem cells (BMMSCs) can act as progenitor cells and transdifferentiate across lineage boundaries. However, whether this unrestricted lineage has specificities depending on the stem cell type is unknown. Placental-derived mesenchymal stem cells (PDMSCs), an easily accessible and less invasive source, are extremely useful materials in current stem cell therapies. No studies have comprehensively analyzed the transition in morphology, surface antigens, metabolism and multilineage potency of differentiated PDMSCs after their dedifferentiation. In this study, we showed that after withdrawing extrinsic factors, adipogenic PDMSCs reverted to a primitive cell population and retained stem cell characteristics. The mitochondrial network during differentiation and dedifferentiation may serve as a marker of absent or acquired pluripotency in various stem cell models. The new population proliferated faster than unmanipulated PDMSCs and could be differentiated into adipocytes, osteocytes and hepatocytes. The cell adhesion molecules (CAMs) signaling pathway and extracellular matrix (ECM) components modulate cell behavior and enable the cells to proliferate or differentiate during the differentiation, dedifferentiation and redifferentiation processes in our study. These observations indicate that the dedifferentiated PDMSCs are distinguishable from the original PDMSCs and may serve as a novel source in stem cell biology and cell-based therapeutic strategies. Furthermore, whether PDMSCs differentiated into other lineages can be dedifferentiated to a primitive cell population needs to be investigated. PMID:26986509

  4. Immobilization of cross linked Col-I–OPN bone matrix protein on aminolysed PCL surfaces enhances initial biocompatibility of human adipogenic mesenchymal stem cells (hADMSC)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Hee; Jyoti, Md. Anirban; Song, Ho-Yeon, E-mail: songmic@sch.ac.kr

    2014-06-01

    In bone tissue engineering surface modification is considered as one of the important ways of fabricating successful biocompatible material. Addition of biologically active functionality on the surfaces has been tried for improving the overall biocompatibility of the system. In this study poly-ε-caprolactone film surfaces have been modified through aminolysis and immobilization process. Collagen type I (COL-I) and osteopontin (OPN), which play an important role in osteogenesis, was immobilized onto PCL films followed by aminolysis treatment using 1,6-hexanediamine. Characterization of animolysed and immobilized surfaces were done by a number techniques using scanning electron microscopy (SEM), FT-IR, XPS, ninhydrin staining, SDS-PAGE and confocal microscopy and compared between the modified and un-modified surfaces. Results of the successive experiments showed that aminolysis treatment was homogeneously achieved which helped to entrap or immobilize Col-I–OPN proteins on surfaces of PCL film. In vitro studies with human adipogenic mesenchymal stem cells (hADMSC) also confirmed the attachment and proliferation of cells was better in modified PCL surfaces than the unmodified surfaces. SEM, confocal microscopy and MTT assay showed a significant increase in cell spreading, attachment and proliferations on the biofunctionalized surfaces compared to the unmodified PCL surfaces at all-time points indicating the success of surface biofunctionalization.

  5. Impaired expression of mitochondrial and adipogenic genes in adipose tissue from a patient with acquired partial lipodystrophy (Barraquer-Simons syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Guallar Jordi P

    2008-08-01

    Full Text Available Abstract Introduction Acquired partial lipodystrophy or Barraquer-Simons syndrome is a rare form of progressive lipodystrophy. The etiopathogenesis of adipose tissue atrophy in these patients is unknown. Case presentation This is a case report of a 44-year-old woman with acquired partial lipodystrophy. To obtain insight into the molecular basis of lipoatrophy in acquired partial lipodystrophy, we examined gene expression in adipose tissue from this patient newly diagnosed with acquired partial lipodystrophy. A biopsy of subcutaneous adipose tissue was obtained from the patient, and DNA and RNA were extracted in order to evaluate mitochondrial DNA abundance and mRNA expression levels. Conclusion The expression of marker genes of adipogenesis and adipocyte metabolism, including the master regulator PPARγ, was down-regulated in subcutaneous adipose tissue from this patient. Adiponectin mRNA expression was also reduced but leptin mRNA levels were unaltered. Markers of local inflammatory status were unaltered. Expression of genes related to mitochondrial function was reduced despite unaltered levels of mitochondrial DNA. It is concluded that adipogenic and mitochondrial gene expression is impaired in adipose tissue in this patient with acquired partial lipodystrophy.

  6. Efficient delivery of C/EBP beta gene into human mesenchymal stem cells via polyethylenimine-coated gold nanoparticles enhances adipogenic differentiation

    Science.gov (United States)

    Joydeep, Das; Choi, Yun-Jung; Yasuda, Hideyo; Han, Jae Woong; Park, Chankyu; Song, Hyuk; Bae, Hojae; Kim, Jin-Hoi

    2016-01-01

    The controlled differentiation of stem cells via the delivery of specific genes encoding appropriate differentiation factors may provide useful models for regenerative medicine and aid in developing therapies for human patients. However, the majority of non-viral vectors are not efficient enough to manipulate difficult-to-transfect adult human stem cells in vitro. Herein, we report the first use of 25 kDa branched polyethylenimine-entrapped gold nanoparticles (AuPEINPs) and covalently bound polyethylenimine-gold nanoparticles (AuMUAPEINPs) as carriers for efficient gene delivery into human mesenchymal stem cells (hMSCs). We determined a functional application of these nanoparticles by transfecting hMSCs with the C/EBP beta gene, fused to EGFP, to induce adipogenic differentiation. Transfection efficacy with AuPEINPs and AuMUAPEINPs was 52.3% and 40.7%, respectively, which was 2.48 and 1.93 times higher than that by using Lipofectamine 2000. Luciferase assay results also demonstrated improved gene transfection efficiency of AuPEINPs/AuMUAPEINPs over Lipofectamine 2000 and polyethylenimine. Overexpression of exogenous C/EBP beta significantly enhanced adipogenesis in hMSCs as indicated by both of Oil Red O staining and mRNA expression analyses. Nanoparticle/DNA complexes exhibited favorable cytocompatibility in hMSCs. Taken together, AuPEINPs and AuMUAPEINPs potentially represent safe and highly efficient vehicles for gene delivery to control hMSC differentiation and for therapeutic gene delivery applications. PMID:27677463

  7. A review on adipogenic differentiation of adipose-derived stem cells%脂肪干细胞成脂分化的研究进展

    Institute of Scientific and Technical Information of China (English)

    陈犹白; 陈聪慧(综述); Qixu Zhang; 韩岩(审校)

    2016-01-01

    Soft tissue defect results from trauma and tumor resection is the common problem in plastic surgery. Existing methods such as tissue flap transplantation, artificial material filling and fat transplantation are not perfect. Adipose-derived stem cells (ASCs) are multipotent stem cells isolated from adipose tissue. Stem cell therapy and adipose tissue engineering based on the adipogenic differentiation capacity of ASCs are promising in plastic and aesthetic surgery and regenerative medicine. The in vitro induction of ASCs differentiation towards adipocyte using medication and chemical was well established. Previous studies showed that various scaffold including decellularized adipose tissue scaffold facilitated ASCs adhesion, proliferation and adipogenic differentiation through mimicking in vivo microenvironment, however its mechanism is not well understood. Factors which could affect ASCs adipocyte differentiation include donor factors such as species, age, gender, anatomic site, and harvesting technique; experimental factors such as cell subpopulation, cell passage, culture condition, and cryopreservation;growth factors such as epidermal growth factor, fibroblast growth factor, vascular endothelial growth factor, insulin-like growth factor, bone morphogenetic proteins, and Nel-like type 1 molecule; hormones such as insulin, glucocorticoids, estrogen, growth hormone, and leptin; chemical like IBMX, paclitaxel and glucagon-like peptide-1;physical factors like radiation and laser; other factors such as Toll-like receptors, platelet-rich plasma and fibrin, human adenovirus-36,and core binding factorα1. Therefore, it is crucial to combine the abovementioned factors and scaffold for improvement of ASCs proliferation and specific differentiation. This review focused on the induction and verification methods, factors and their mechanisms of ASCs adipogenic differentiation. We also introduced our experience and looked forward the future research interest of ASCs adipogenic

  8. Adipogenic placenta-derived mesenchymal stem cells are not lineage restricted by withdrawing extrinsic factors: developing a novel visual angle in stem cell biology.

    Science.gov (United States)

    Hu, C; Cao, H; Pan, X; Li, J; He, J; Pan, Q; Xin, J; Yu, X; Li, J; Wang, Y; Zhu, D; Li, L

    2016-01-01

    Current evidence implies that differentiated bone marrow mesenchymal stem cells (BMMSCs) can act as progenitor cells and transdifferentiate across lineage boundaries. However, whether this unrestricted lineage has specificities depending on the stem cell type is unknown. Placental-derived mesenchymal stem cells (PDMSCs), an easily accessible and less invasive source, are extremely useful materials in current stem cell therapies. No studies have comprehensively analyzed the transition in morphology, surface antigens, metabolism and multilineage potency of differentiated PDMSCs after their dedifferentiation. In this study, we showed that after withdrawing extrinsic factors, adipogenic PDMSCs reverted to a primitive cell population and retained stem cell characteristics. The mitochondrial network during differentiation and dedifferentiation may serve as a marker of absent or acquired pluripotency in various stem cell models. The new population proliferated faster than unmanipulated PDMSCs and could be differentiated into adipocytes, osteocytes and hepatocytes. The cell adhesion molecules (CAMs) signaling pathway and extracellular matrix (ECM) components modulate cell behavior and enable the cells to proliferate or differentiate during the differentiation, dedifferentiation and redifferentiation processes in our study. These observations indicate that the dedifferentiated PDMSCs are distinguishable from the original PDMSCs and may serve as a novel source in stem cell biology and cell-based therapeutic strategies. Furthermore, whether PDMSCs differentiated into other lineages can be dedifferentiated to a primitive cell population needs to be investigated. PMID:26986509

  9. Role of C/EBPβ-LAP and C/EBPβ-LIP in early adipogenic differentiation of human white adipose-derived progenitors and at later stages in immature adipocytes.

    Science.gov (United States)

    Lechner, Stefan; Mitterberger, Maria C; Mattesich, Monika; Zwerschke, Werner

    2013-01-01

    We investigated the role of the major isoforms of CCAAT enhancer binding protein β (C/EBPβ), C/EBPβ-LAP and C/EBPβ-LIP, in adipogenesis of human white adipose-derived stromal/progenitor cells (ASC). C/EBPβ gene expression was transiently induced early in adipogenesis. At later stages, in immature adipocytes, the C/EBPβ mRNA and protein levels declined. The C/EBPβ-LIP protein steady-state level decreased considerably stronger than the C/EBPβ-LAP level and the C/EBPβ-LIP half-life was significantly shorter than the C/EBPβ-LAP half-life. The turn-over of both C/EBPβ-isoforms was regulated by ubiquitin/proteasome-dependent degradation. These data suggest that the protein stability of the C/EBPβ-isoforms is differentially regulated in the course of adipogenesis and in immature adipocytes. Constitutive overexpression of C/EBPβ-LIP had antiadipogenic activity in human ASC. C/EBPβ-LAP, which promotes adipogenesis in mouse 3T3-L1 preadipocytes by directly activating expression of the adipogenic keyregulator PPARγ2, induced the expression of PPARγ2 and of the adipocyte differentiation gene product FABP4 in confluent ASC in the absence of adipogenic hormones. At later stages after hormone cocktail-induced adipogenesis, in immature adipocytes, constitutive overexpression of C/EBPβ-LAP led to reduced expression of PPARγ2 and FABP4, C/EBPα expression was downregulated and the expression of the adipocyte differentiation gene products adiponectin and leptin was impaired. These findings suggest that constitutive overexpression of C/EBPβ-LAP induces adipogenesis in human ASC and negatively regulates the expression of adipogenic regulators and certain adipocyte differentiation gene products in immature adipocytes. We conclude the regulation of both C/EBPβ gene expression and C/EBPβ-LIP and C/EBPβ-LAP protein turn-over plays an important role for the expression of adipogenic regulators and/or adipocyte differentiation genes in early adipogenic differentiation of

  10. Insights into the O-Acetylation Reaction of Hydroxylated Heterocyclic Amines by Human Arylamine N-Acetyltransferases: A Computational Study

    Energy Technology Data Exchange (ETDEWEB)

    Lau, E Y; Felton, J S; Lightstone, F C

    2006-06-06

    A computational study was performed to better understand the differences between human arylamine N-acetyltransferase (NAT) 1 and 2. Homology models were constructed from available crystal structures and comparisons of the active site residues 125, 127, and 129 for these two enzymes provide insight into observed substrate differences. The NAT2 model provided a basis for understanding how some of the common mutations may affect the structure of the protein. Molecular dynamics simulations of the human NAT models and the template structure (NAT from Mycobacterium smegmatis) were performed and showed the models to be stable and reasonable. Docking studies of hydroxylated heterocyclic amines in the models of NAT1 and NAT2 probed the differences exhibited by these two proteins with mutagenic agents. The hydroxylated heterocyclic amines were only able to fit into the NAT2 active site, and an alternative binding site by the P-loop was found using our models and will be discussed. Additionally, quantum mechanical calculations were performed to study the O-acetylation reaction of the hydroxylated heterocyclic amines N-OH MeIQx and N-OH PhIP. This study has given us insight into why there are substrate differences among isoenzymes and explains some of the polymorphic activity differences.

  11. N-acetyltransferase-2 and medical history in bladder cancer cases with a suspected occupational disease (BK 1301) in Germany.

    Science.gov (United States)

    Weistenhofer, Wobbeke; Blaszkewicz, Meinolf; Bolt, Hermann M; Golka, Klaus

    2008-01-01

    In 187 bladder cancer cases reported to the employers' liability insurance association in Germany as suspected cases of an occupational disease produced by aromatic amines, N- acetyltransferase-2 (NAT2) activity status, occupational exposure data, period of latency, and clinical parameters were determined. In 83 out of 187 cases surveyed within the period 1991-1999, the NAT2 acetylator status was investigated by determining the molar ratio of an acetylated and a nonacetylated caffeine metabolite in urine (phenotyping) and/or by NAT2 genotyping according to standard polymerase chain reaction (PCR) protocol. The proportion of slow NAT2 acetylators in the surveyed 83 bladder cancer cases was 67%. In the entire group of surveyed 187 cases, mean duration of exposure was 17.6 yr and mean period of latency was 34.7 yr. Occupational exposures to potential bladder carcinogens were observed in 73 occupations, including chemical industry (25%), and occupations as a painter and/or varnisher (23%) were most often encountered. In 12% of the surveyed bladder cancer cases, a second primary malignancy was observed. The NAT2 distribution observed in the 83 cases is comparable to the proportion in 40 occupationally exposed bladder cancer cases in a Department of Urology located close to a former German production site of benzidine-based azo dyes, but higher than in most studies involving NAT2 genetic status in bladder cancer cases.

  12. Absence of Rtt109p, a fungal-specific histone acetyltransferase, results in improved acetic acid tolerance of Saccharomyces cerevisiae.

    Science.gov (United States)

    Cheng, Cheng; Zhao, Xinqing; Zhang, Mingming; Bai, Fengwu

    2016-03-01

    RTT109 is a histone acetyltransferase for the acetylation of histone H3. It is still not clear whether RTT109 plays a role in regulation of gene expression under environmental stresses. In this study, the involvement of RTT109 in acetic acid stress tolerance of Saccharomyces cerevisiae was investigated. It was revealed that the absence of RTT109 enhanced resistance to 5.5 g L(-1) acetic acid, which was indicated by improved growth of RTT109Δ mutant compared with that of the wild-type BY4741 strain. Meanwhile, the lag phase was shortened for 48 h and glucose consumption completed 36 h in advance for RTT109Δ mutant compared to the wild-type strain, with ethanol production rate increased from 0.39 to 0.60 g L(-1) h(-1). Significantly, elevated transcription levels of HSP12, CTT1 and GSH1, as well as increased activities of antioxidant enzymes were observed in RTT109Δ under acetic acid stress. Improved flocculation of RTT109Δ compared to that of the control strain BY4741 under the acetic acid stress was also observed. These results suggest that the absence of RTT109 not only activates transcription of stress responsive genes, but also improves resistance to oxidative stress, which ultimately contributes to improved acetic acid tolerance in S. cerevisiae.

  13. Crohn's disease in Japanese is associated with a SNP-haplotype of N-acetyltransferase 2 gene

    Institute of Scientific and Technical Information of China (English)

    Haruhisa Machida; Ikuo Murata; Shigeru Kohno; Chen-Yang Wen; Kazuhiro Tsukamoto; Chun-Yang Wen; Saburou Shikuwa; Hajime Isomoto; Yohei Mizuta; Fuminao Takeshima; Kunihiko Murase; Naomichi Matsumoto

    2005-01-01

    AIM: To investigate the frequency and distribution of N-acetyltransferase 2 (NAT2) and uridine 5′-diphosphate (UDP)-glucuronosyltransferase 1A7 (UGT1A7) genes in patients with ulcerative colitis (UC) and Crohn's disease (CD).METHODS: Frequencies and distributions of NAT2 and UGT1A7SNPs as well as their haplotypes were investigated in 95 patients with UC, 60 patients with CD, and 200gender-matched, unrelated, healthy, control volunteers by PCR-restriction fragment length polymorphism (RFLP),PCR-denaturing high-performance liquid chromatography (DHPLC), and direct DNA sequencing.RESULTS: Multiple logistic regression analysis revealed that the frequency of haplotype, NAT2*7B, significantly increased in CD patients, compared to that in controls (P= 0.0130, OR = 2.802, 95%CI = 1.243-6.316). However,there was no association between NAT2 haplotypes and UC, or between any UGT1A7haplotypes and inflammatory bowel disease (IBD).CONCLUSION: It is likely that the NAT2 gene is one of the determinants for CD in Japanese. Alternatively, a new CD determinant may exist in the 8p22 region, whereNAT2is located.

  14. Method to produce acetyldiacylglycerols (ac-TAGs) by expression of an acetyltransferase gene isolated from Euonymus alatus (burning bush)

    Energy Technology Data Exchange (ETDEWEB)

    Durrett, Timothy; Ohlrogge, John; Pollard, Michael

    2016-05-03

    The present invention relates to novel diacylglycerol acyltransferase genes and proteins, and methods of their use. In particular, the invention describes genes encoding proteins having diacylglycerol acetyltransferase activity, specifically for transferring an acetyl group to a diacylglycerol substrate to form acetyl-Triacylglycerols (ac-TAGS), for example, a 3-acetyl-1,2-diacyl-sn-glycerol. The present invention encompasses both native and recombinant wild-type forms of the transferase, as well as mutants and variant forms. The present invention also relates to methods of using novel diacylglycerol acyltransferase genes and proteins, including their expression in transgenic organisms at commercially viable levels, for increasing production of 3-acetyl-1,2-diacyl-sn-glycerols in plant oils and altering the composition of oils produced by microorganisms, such as yeast, by increasing ac-TAG production. Additionally, oils produced by methods of the present inventions comprising genes and proteins are contemplated for use as biodiesel fuel, in polymer production and as naturally produced food oils with reduced calories.

  15. A naturally-occurring histone acetyltransferase inhibitor derived from Garcinia indica impairs newly acquired and reactivated fear memories.

    Directory of Open Access Journals (Sweden)

    Stephanie A Maddox

    Full Text Available The study of the cellular and molecular mechanisms underlying the consolidation and reconsolidation of traumatic fear memories has progressed rapidly in recent years, yet few compounds have emerged that are readily useful in a clinical setting for the treatment of anxiety disorders such as post-traumatic stress disorder (PTSD. Here, we use a combination of biochemical, behavioral, and neurophysiological methods to systematically investigate the ability of garcinol, a naturally-occurring histone acetyltransferase (HAT inhibitor derived from the rind of the fruit of the Kokum tree (Garcina indica, to disrupt the consolidation and reconsolidation of Pavlovian fear conditioning, a widely studied rodent model of PTSD. We show that local infusion of garcinol into the rat lateral amygdala (LA impairs the training and retrieval-related acetylation of histone H3 in the LA. Further, we show that either intra-LA or systemic administration of garcinol within a narrow window after either fear conditioning or fear memory retrieval significantly impairs the consolidation and reconsolidation of a Pavlovian fear memory and associated neural plasticity in the LA. Our findings suggest that a naturally-occurring compound derived from the diet that regulates chromatin function may be useful in the treatment of newly acquired or recently reactivated traumatic memories.

  16. Prevalence of the N-Acetyltransferase (NAT2 gene polymorphism 282C>T in Peruvian population and health implications

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    Salazar-Granara Alberto

    2016-03-01

    Full Text Available Objective: To determine the frequency of the C282T polymorphism of the NAT2 gene (N acetyltransferase in Peruvian populations. Field work, focused on exploring genetic risk factor in Peruvian populations, which has influence in the response to drugs and malignancies aetiology. Material and Methods: Cross-sectional study. 166 voluntaries from Lima, Lambayeque, Apurimac, Puno, San Martin, Amazonas and Loreto were enrolled. The sampling was done by convenience and it was use the RFLP-PCR conventional technique was used. Results: The allele frequency were 54% (n=126 for C282 and 46% (n=106 for T282. For the T allele, by its orign , stand out 2 those which origins were Lima 42% (n=25, Amazonas 47% (n=16, San Martin 74% (n=28 and Apurimac 50% (n=13 (X , p>0.05. A global genotype frequency were 26.7% (n=31 for C282/C282, 56.0% (n=65 for C282/T282 and 17.2% (n=20 for T282/T282 (Hardy Weinberg Test p>0.05. By origin, Puno presented allelic imbalance (Hardy Weinberg test p0.05. Conclusion: The overall frequency of NAT2 allele T282 was 46%; San Martin had the highest prevalence (74%. The T282 allele is linked to neoplastic diseases and adverse reactions to anti-TB drugs, these results will be used for the application of pharmacogenetics in Peru

  17. The Acetyl Group Buffering Action of Carnitine Acetyltransferase Offsets Macronutrient-Induced Lysine Acetylation of Mitochondrial Proteins

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    Michael N. Davies

    2016-01-01

    Full Text Available Lysine acetylation (AcK, a posttranslational modification wherein a two-carbon acetyl group binds covalently to a lysine residue, occurs prominently on mitochondrial proteins and has been linked to metabolic dysfunction. An emergent theory suggests mitochondrial AcK occurs via mass action rather than targeted catalysis. To test this hypothesis, we performed mass spectrometry-based acetylproteomic analyses of quadriceps muscles from mice with skeletal muscle-specific deficiency of carnitine acetyltransferase (CrAT, an enzyme that buffers the mitochondrial acetyl-CoA pool by converting short-chain acyl-CoAs to their membrane permeant acylcarnitine counterparts. CrAT deficiency increased tissue acetyl-CoA levels and susceptibility to diet-induced AcK of broad-ranging mitochondrial proteins, coincident with diminished whole body glucose control. Sub-compartment acetylproteome analyses of muscles from obese mice and humans showed remarkable overrepresentation of mitochondrial matrix proteins. These findings reveal roles for CrAT and L-carnitine in modulating the muscle acetylproteome and provide strong experimental evidence favoring the nonenzymatic carbon pressure model of mitochondrial AcK.

  18. Adolescent, but not adult, binge ethanol exposure leads to persistent global reductions of choline acetyltransferase expressing neurons in brain.

    Directory of Open Access Journals (Sweden)

    Ryan P Vetreno

    Full Text Available During the adolescent transition from childhood to adulthood, notable maturational changes occur in brain neurotransmitter systems. The cholinergic system is composed of several distinct nuclei that exert neuromodulatory control over cognition, arousal, and reward. Binge drinking and alcohol abuse are common during this stage, which might alter the developmental trajectory of this system leading to long-term changes in adult neurobiology. In Experiment 1, adolescent intermittent ethanol (AIE; 5.0 g/kg, i.g., 2-day on/2-day off from postnatal day [P] 25 to P55 treatment led to persistent, global reductions of choline acetyltransferase (ChAT expression. Administration of the Toll-like receptor 4 agonist lipopolysaccharide to young adult rats (P70 produced a reduction in ChAT+IR that mimicked AIE. To determine if the binge ethanol-induced ChAT decline was unique to the adolescent, Experiment 2 examined ChAT+IR in the basal forebrain following adolescent (P28-P48 and adult (P70-P90 binge ethanol exposure. Twenty-five days later, ChAT expression was reduced in adolescent, but not adult, binge ethanol-exposed animals. In Experiment 3, expression of ChAT and vesicular acetylcholine transporter expression was found to be significantly reduced in the alcoholic basal forebrain relative to moderate drinking controls. Together, these data suggest that adolescent binge ethanol decreases adult ChAT expression, possibly through neuroimmune mechanisms, which might impact adult cognition, arousal, or reward sensitivity.

  19. Severe congenital myasthenia gravis of the presynaptic type with choline acetyltransferase mutation in a Chinese infant with respiratory failure.

    Science.gov (United States)

    Yeung, Wai L; Lam, Ching W; Fung, Lai W E; Hon, Kam L E; Ng, Pak C

    2009-01-01

    We report a severe case of congenital myasthenia gravis in a Chinese newborn who presented with complete ptosis, severe hypotonia, dysphagia and respiratory insufficiency with recurrent apnea that required mechanical ventilatory support since birth. Routine neurophysiologic studies, including the 3-Hz repetitive stimulation test and electromyogram were normal. Neostigmine and edrophonium tests were also negative. However, decremental response to 3-Hz stimulation became apparent after depleting the muscles with trains of 10-Hz stimuli for 10 min. The infant was subsequently confirmed to have heterozygous mutations in the choline acetyltransferase genes, p.T553N and p.S704P. Both missense mutations are novel mutations. The child remained on positive pressure ventilation at 3 years of age despite treatment with high-dose anticholinesterase. This case highlights the difficulty of making an early diagnosis based on clinical presentation and routine electrophysiologic tests, especially when neonatologists are not familiar with this condition. Further, as there are different genetic defects causing different types of congenital myasthenia gravis, anticholinesterase therapy may be beneficial to some but detrimental to others. Therefore, the exact molecular diagnosis is an important guide to therapy. A high index of suspicion coupled with extended electrodiagnostic tests in clinically suspected patients will ensure the selection of appropriate genetic molecular study for confirming the diagnosis. PMID:18797171

  20. Co-expression of G2-EPSPS and glyphosate acetyltransferase GAT genes conferring high tolerance to glyphosate in soybean

    Directory of Open Access Journals (Sweden)

    Bingfu eGuo

    2015-10-01

    Full Text Available Glyphosate is a widely used non-selective herbicide with broad spectrum of weed control around the world. At present, most of the commercial glyphosate tolerant soybeans utilize glyphosate tolerant gene CP4-EPSPS or glyphosate acetyltransferase gene GAT separately. In this study, both glyphosate tolerant gene G2-EPSPS and glyphosate degraded gene GAT were co-transferred into soybean and transgenic plants showed high tolerance to glyphosate. Molecular analysis including PCR, Sothern blot, qRT-PCR and Western blot revealed that target genes have been integrated into genome and expressed effectively at both mRNA and protein levels. Furthermore, the glyphosate tolerance analysis showed that no typical symptom was observed when compared with a glyphosate tolerant line HJ06-698 derived from GR1 transgenic soybean even at four-fold labeled rate of Roundup. Chlorophyll and shikimic acid content analysis of transgenic plant also revealed that these two indexes were not significantly altered after glyphosate application. These results indicated that co-expression of G2-EPSPS and GAT conferred high tolerance to the herbicide glyphosate in soybean. Therefore, combination of tolerant and degraded genes provides a new strategy for developing glyphosate tolerant transgenic crops.

  1. What a Role did Histidine Residue Play in Arylamine N-Acetyltransferase 2 Acetylation? A Quantum Chemistry Study

    Institute of Scientific and Technical Information of China (English)

    QIAO Qing-An; CAI Zheng-Ting; YANG Chuan-Lu; WANG Mei-Shan

    2006-01-01

    Arylamine N-acetyltransferases (NATs, EC 2.3.1.5) catalyze an acetyl group transfer from acetyl coenzyme A (AcCoA) to primary arylamines and play a very important role in the metabolism and bioactivation of drugs and carcinogens. Experiments revealed that His-107 was likely the residues responsible for mediating acetyl transfer.The full catalytic mechanism of acetylation process has been examined by density functional theory. The results indicate that, if the acetyl group is directly transferred from the donor, p-nitrophenyl acetate, to the acceptor, cysteine,the high activation energy will be a great hindrance. These energies have dropped in a little range of 20-25 k J/mol when His-107 assisted the transfer process. However, when protonated His-107 mediated the reaction, the activation energies have been dropped about 73-85 kJ/mol. Our calculations strongly supported an enzyme acetylation mechanism that experiences a thiolate-imidazolium pair, and verified the presumption from experiments.

  2. Melatonin production in Escherichia coli by dual expression of serotonin N-acetyltransferase and caffeic acid O-methyltransferase.

    Science.gov (United States)

    Byeon, Yeong; Back, Kyoungwhan

    2016-08-01

    Melatonin is a well-known bioactive molecule produced in animals and plants and a well-studied natural compound. Two enzymatic steps are required for the biosynthesis of melatonin from serotonin. First, serotonin N-acetyltransferase (SNAT) catalyzes serotonin to N-acetylserotonin (NAS) followed by the action of N-acetylserotonin O-methyltransferase (ASMT), resulting in the synthesis of O-methylated NAS, also known as melatonin. Attempts to document melatonin production in Escherichia coli have been unsuccessful to date due to either low enzyme activity or inactive ASMT expression. Here, we employed caffeic acid O-methyltransferase (COMT) instead of ASMT, as COMT is a multifunctional enzyme that has ASMT activity as well. Among several combinations of dual expression cassettes, recombinant E. coli that expressed sheep SNAT with rice COMT produced a high quantity of melatonin, which was measured in a culture medium (1.46 mg/L in response to 1 mM serotonin). This level was several orders of magnitude higher than that produced in transgenic rice and tomato overexpressing sheep SNAT and ASMT, respectively. This heterologous expression system can be widely employed to screen various putative SNAT or ASMT genes from animals and plants as well as to overproduce melatonin in various useful microorganisms. PMID:27005412

  3. N-Acetyltransferase 1 (NAT1) Genotype: A Risk Factor for Urinary Bladder Cancer in a Lebanese Population

    Science.gov (United States)

    Yassine, Ibrahim A.; Kobeissi, Loulou; Jabbour, Michel E.; Dhaini, Hassan R.

    2012-01-01

    In Lebanon, bladder cancer is the second most incident cancer among men. This study investigates a possible association between N-acetyltransferase 1 (NAT1) genotype, a drug-metabolizing enzyme coding gene, and bladder cancer in Lebanese men. A case-control study (54 cases and 105 hospital-based controls) was conducted in two major hospitals in Beirut. Cases were randomly selected from patients diagnosed in the period of 2002–2008. Controls were conveniently identified and selected from the same settings. Data was collected using interview questionnaire and blood analysis. NAT1 genotypes were determined by PCR-RFLP. Statistical analysis revolved around univariate, bivariate, and multivariate logistic regression models, along with checks for effect modification. Results showed NAT1∗14A allele, smoking, occupational exposure to combustion fumes, and prostate-related symptoms, to be risk factors for bladder cancer. The odds of carrying at least one NAT1∗14A allele are 7 times higher in cases compared to controls (OR = 7.86, 95% CI: 1.53–40.39). A gene-environment interaction was identified for NAT1∗14A allele with occupational exposure to combustion fumes. Among carriers of NAT1∗14A allele, the odds of bladder cancer dropped to 2.03 from 3.72. Our study suggests NAT1∗14A allele as a possible biomarker for bladder cancer. Further research is recommended to confirm this association. PMID:22956951

  4. N-Acetyltransferase 1 (NAT1 Genotype: A Risk Factor for Urinary Bladder Cancer in a Lebanese Population

    Directory of Open Access Journals (Sweden)

    Ibrahim A. Yassine

    2012-01-01

    Full Text Available In Lebanon, bladder cancer is the second most incident cancer among men. This study investigates a possible association between N-acetyltransferase 1 (NAT1 genotype, a drug-metabolizing enzyme coding gene, and bladder cancer in Lebanese men. A case-control study (54 cases and 105 hospital-based controls was conducted in two major hospitals in Beirut. Cases were randomly selected from patients diagnosed in the period of 2002–2008. Controls were conveniently identified and selected from the same settings. Data was collected using interview questionnaire and blood analysis. NAT1 genotypes were determined by PCR-RFLP. Statistical analysis revolved around univariate, bivariate, and multivariate logistic regression models, along with checks for effect modification. Results showed NAT1∗14A allele, smoking, occupational exposure to combustion fumes, and prostate-related symptoms, to be risk factors for bladder cancer. The odds of carrying at least one NAT1∗14A allele are 7 times higher in cases compared to controls (OR=7.86, 95% CI: 1.53–40.39. A gene-environment interaction was identified for NAT1∗14A allele with occupational exposure to combustion fumes. Among carriers of NAT1∗14A allele, the odds of bladder cancer dropped to 2.03 from 3.72. Our study suggests NAT1∗14A allele as a possible biomarker for bladder cancer. Further research is recommended to confirm this association.

  5. Raman and surface enhanced Raman spectroscopic studies of specific, small molecule activator of histone acetyltransferase p300

    Science.gov (United States)

    Kundu, Partha P.; Pavan Kumar, G. V.; Mantelingu, Kempegowda; Kundu, Tapas K.; Narayana, Chandrabhas

    2011-07-01

    We report for the first time, the Raman and surface enhanced Raman scattering (SERS) studies of N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-benzamide (CTB). This molecule is specific activator of human histone acetyltransferase (HAT), p300, and serves as lead molecule to design anti-neoplastic therapeutics. A detailed Raman and SERS band assignments have been performed for CTB, which are compared with the density functional theory calculations. The observed red shift of N sbnd H stretching frequency from the computed wavenumber indicates the weakening of N sbnd H bond resulting from proton transfer to the neighboring oxygen atom. We observe Ag sbnd N vibrational mode at 234 cm -1 in SERS of CTB. This indicates there is a metal-molecule bond leading to chemical enhancement in SERS. We also observe, enhancement in the modes pertaining to substituted benzene rings and methyl groups. Based on SERS analysis we propose the adsorption sites and the orientation of CTB on silver surface.

  6. Homologues of xenobiotic metabolizing N-acetyltransferases in plant-associated fungi: Novel functions for an old enzyme family.

    Science.gov (United States)

    Karagianni, Eleni P; Kontomina, Evanthia; Davis, Britton; Kotseli, Barbara; Tsirka, Theodora; Garefalaki, Vasiliki; Sim, Edith; Glenn, Anthony E; Boukouvala, Sotiria

    2015-01-01

    Plant-pathogenic fungi and their hosts engage in chemical warfare, attacking each other with toxic products of secondary metabolism and defending themselves via an arsenal of xenobiotic metabolizing enzymes. One such enzyme is homologous to arylamine N-acetyltransferase (NAT) and has been identified in Fusarium infecting cereal plants as responsible for detoxification of host defence compound 2-benzoxazolinone. Here we investigate functional diversification of NAT enzymes in crop-compromising species of Fusarium and Aspergillus, identifying three groups of homologues: Isoenzymes of the first group are found in all species and catalyse reactions with acetyl-CoA or propionyl-CoA. The second group is restricted to the plant pathogens and is active with malonyl-CoA in Fusarium species infecting cereals. The third group generates minimal activity with acyl-CoA compounds that bind non-selectively to the proteins. We propose that fungal NAT isoenzymes may have evolved to perform diverse functions, potentially relevant to pathogen fitness, acetyl-CoA/propionyl-CoA intracellular balance and secondary metabolism. PMID:26245863

  7. Structure and nucleosome interaction of the yeast NuA4 and Piccolo-NuA4 histone acetyltransferase complexes.

    Science.gov (United States)

    Chittuluru, Johnathan R; Chaban, Yuriy; Monnet-Saksouk, Julie; Carrozza, Michael J; Sapountzi, Vasileia; Selleck, William; Huang, Jiehuan; Utley, Rhea T; Cramet, Myriam; Allard, Stephane; Cai, Gang; Workman, Jerry L; Fried, Michael G; Tan, Song; Côté, Jacques; Asturias, Francisco J

    2011-10-09

    We have used EM and biochemistry to characterize the structure of NuA4, an essential yeast histone acetyltransferase (HAT) complex conserved throughout eukaryotes, and we have determined the interaction of NuA4 with the nucleosome core particle (NCP). The ATM-related Tra1 subunit, which is shared with the SAGA coactivator complex, forms a large domain joined to a second region that accommodates the catalytic subcomplex Piccolo and other NuA4 subunits. EM analysis of a NuA4-NCP complex shows the NCP bound at the periphery of NuA4. EM characterization of Piccolo and Piccolo-NCP provided further information about subunit organization and confirmed that histone acetylation requires minimal contact with the NCP. A small conserved region at the N terminus of Piccolo subunit enhancer of Polycomb-like 1 (Epl1) is essential for NCP interaction, whereas the subunit yeast homolog of mammalian Ing1 2 (Yng2) apparently positions Piccolo for efficient acetylation of histone H4 or histone H2A tails. Taken together, these results provide an understanding of the NuA4 subunit organization and the NuA4-NCP interactions.

  8. The acetyltransferase HAT1 moderates the NF-κB response by regulating the transcription factor PLZF.

    Science.gov (United States)

    Sadler, Anthony J; Suliman, Bandar A; Yu, Liang; Yuan, Xiangliang; Wang, Die; Irving, Aaron T; Sarvestani, Soroush T; Banerjee, Ashish; Mansell, Ashley S; Liu, Jun-Ping; Gerondakis, Steve; Williams, Bryan R G; Xu, Dakang

    2015-01-01

    To date, the activities of protein kinases have formed the core of our understanding of cell signal transduction. Comprehension of the extent of protein acetylation has raised expectations that this alternate post-transcriptional modification will be shown to rival phosphorylation in its importance in mediating cellular responses. However, limited instances have been identified. Here we show that signalling from Toll-like or TNF-α receptors triggers the calcium/calmodulin-dependent protein kinase (CaMK2) to activate histone acetyltransferase-1 (HAT1), which then acetylates the transcriptional regulator PLZF. Acetylation of PLZF promotes the assembly of a repressor complex incorporating HDAC3 and the NF-κB p50 subunit that limits the NF-κB response. Accordingly, diminishing the activity of CaMK2, the expression levels of PLZF or HAT1, or mutating key residues that are covalently modified in PLZF and HAT1, curtails control of the production of inflammatory cytokines. These results identify a central role for acetylation in controlling the inflammatory NF-κB transcriptional programme. PMID:25865065

  9. Phenyllactic Acid from Lactobacillus plantarum PromotesAdipogenic Activity in 3T3-L1 Adipocyte via Up-Regulationof PPAR-γ2

    Directory of Open Access Journals (Sweden)

    Soundharrajan Ilavenil

    2015-08-01

    Full Text Available Synthetic drugs are commonly used to cure various human ailments at present. However, the uses of synthetic drugs are strictly regulated because of their adverse effects. Thus, naturally occurring molecules may be more suitable for curing disease without unfavorable effects. Therefore, we investigated phenyllactic acid (PLA from Lactobacillus plantarum with respect to its effects on adipogenic genes and their protein expression in 3T3-L1 pre-adipocytes by qPCR and western blot techniques. PLA enhanced differentiation and lipid accumulation in 3T3-L1 cells at the concentrations of 25, 50, and 100 μM. Maximum differentiation and lipid accumulation were observed at a concentration of 100 μM of PLA, as compared with control adipocytes (p < 0.05. The mRNA and protein expression of PPAR-γ2, C/EBP‑α, adiponectin, fatty acid synthase (FAS, and SREBP-1 were increased by PLA treatment as compared with control adipocytes (p < 0.05. PLA stimulates PPAR-γ mRNA expression in a concentration dependent manner, but this expression was lesser than agonist (2.83 ± 0.014 fold of PPAR-γ2. Moreover, PLA supplementation enhances glucose uptake in 3T3-L1 pre-adipocytes (11.81 ± 0.17 mM compared to control adipocytes, but this glucose uptake was lesser than that induced by troglitazone (13.75 ± 0.95 mM and insulin treatment (15.49 ± 0.20 mM. Hence, we conclude that PLA treatment enhances adipocyte differentiation and glucose uptake via activation of PPAR-γ2, and PLA may thus be the potential candidate for preventing Type 2 Diabetes Mellitus (T2DM.

  10. Immunohistochemical localization of two types of choline acetyltransferase in neurons and sensory cells of the octopus arm.

    Science.gov (United States)

    Sakaue, Yuko; Bellier, Jean-Pierre; Kimura, Shin; D'Este, Loredana; Takeuchi, Yoshihiro; Kimura, Hiroshi

    2014-01-01

    Cholinergic structures in the arm of the cephalopod Octopus vulgaris were studied by immunohistochemistry using specific antisera for two types (common and peripheral) of acetylcholine synthetic enzyme choline acetyltransferase (ChAT): antiserum raised against the rat common type ChAT (cChAT), which is cross-reactive with molluscan cChAT, and antiserum raised against the rat peripheral type ChAT (pChAT), which has been used to delineate peripheral cholinergic structures in vertebrates, but not previously in invertebrates. Western blot analysis of octopus extracts revealed a single pChAT-positive band, suggesting that pChAT antiserum is cross-reactive with an octopus counterpart of rat pChAT. In immunohistochemistry, only neuronal structures of the octopus arm were stained by cChAT and pChAT antisera, although the pattern of distribution clearly differed between the two antisera. cChAT-positive varicose nerve fibers were observed in both the cerebrobrachial tract and neuropil of the axial nerve cord, while pChAT-positive varicose fibers were detected only in the neuropil of the axial nerve cord. After epitope retrieval, pChAT-positive neuronal cells and their processes became visible in all ganglia of the arm, including the axial and intramuscular nerve cords, and in ganglia of suckers. Moreover, pChAT-positive structures also became detectable in nerve fibers connecting the different ganglia, in smooth nerve fibers among muscle layers and dermal connective tissues, and in sensory cells of the suckers. These results suggest that the octopus arm has two types of cholinergic nerves: cChAT-positive nerves from brain ganglia and pChAT-positive nerves that are intrinsic to the arm.

  11. Choline acetyltransferase expression in rat prefrontal cortex and hippocampus after acute and chronic exposure to amisulpride, haloperidol, and risperidone.

    Science.gov (United States)

    Huang, Guang-Biao; Zhao, Tong; Li, Chun-Rong; Sui, Zhi-Yan; Kang, Nam-In; Han, Eui-Hyeog; Chung, Young-Chul

    2012-10-24

    Recently, there has been an increasing concern that atypical antipsychotics as well as typical ones may cause detrimental effects on cognitive function. Supporting evidence comes from many preclinical studies demonstrating that long-term administration of haloperidol, risperidone, and ziprasidone reduced choline acetyltransferase (ChAT) expression in rat hippocampus (HIP). However, to the best of our knowledge, no studies have examined the effects of amisulpride on ChAT expression in rats. Therefore, the aim of this study was to investigate the effects of acute and chronic administration of amisulpride, haloperidol, and risperidone on ChAT expression in the rat prefrontal cortex (PFC) and HIP. Animals received daily intraperitoneal (i.p.) injections of amisulpride (5 or 100mg/kg), haloperidol (1 or 2mg/kg), risperidone (1 or 2mg/kg) or vehicle for 7 or 45 days. One day after the last injection, rats were sacrificed. ChAT immunoreactivity was assessed with immunofluorescence staining. Target areas of brain were PFC and HIP (CA1, CA3 and DG). The short-term administration of haloperidol and risperidone produced significant decrease of ChAT immunoreactivity in the PFC and HIP compared to vehicle whereas amisulpride had no effects on ChAT immunoreactivity in the PFC and HIP. In long-term study, haloperidol and risperidone decreased ChAT-positive cells and/or fiber pixel density in the PFC and HIP whereas amisulpride decreased ChAT-positive cells in the PFC and had no effects on fiber pixel density of ChAT in the HIP. The results suggest that both short-term and long-term administration of haloperidol and risperidone, and long-term administration of amisulpride may produce detrimental effects on cognitive function by reducing ChAT expression in the PFC and/or HIP.

  12. Catalytic Mechanism of Perosamine N-Acetyltransferase Revealed by High-Resolution X-ray Crystallographic Studies and Kinetic Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Thoden, James B.; Reinhardt, Laurie A.; Cook, Paul D.; Menden, Patrick; Cleland, W.W.; Holden, Hazel M. (UW); (Mount Union); (UW-MED)

    2012-09-17

    N-Acetylperosamine is an unusual dideoxysugar found in the O-antigens of some Gram-negative bacteria, including the pathogenic Escherichia coli strain O157:H7. The last step in its biosynthesis is catalyzed by PerB, an N-acetyltransferase belonging to the left-handed {beta}-helix superfamily of proteins. Here we describe a combined structural and functional investigation of PerB from Caulobacter crescentus. For this study, three structures were determined to 1.0 {angstrom} resolution or better: the enzyme in complex with CoA and GDP-perosamine, the protein with bound CoA and GDP-N-acetylperosamine, and the enzyme containing a tetrahedral transition state mimic bound in the active site. Each subunit of the trimeric enzyme folds into two distinct regions. The N-terminal domain is globular and dominated by a six-stranded mainly parallel {beta}-sheet. It provides most of the interactions between the protein and GDP-perosamine. The C-terminal domain consists of a left-handed {beta}-helix, which has nearly seven turns. This region provides the scaffold for CoA binding. On the basis of these high-resolution structures, site-directed mutant proteins were constructed to test the roles of His 141 and Asp 142 in the catalytic mechanism. Kinetic data and pH-rate profiles are indicative of His 141 serving as a general base. In addition, the backbone amide group of Gly 159 provides an oxyanion hole for stabilization of the tetrahedral transition state. The pH-rate profiles are also consistent with the GDP-linked amino sugar substrate entering the active site in its unprotonated form. Finally, for this investigation, we show that PerB can accept GDP-3-deoxyperosamine as an alternative substrate, thus representing the production of a novel trideoxysugar.

  13. Modification of N-acetyltransferases and glutathione S-transferases by coffee components: possible relevance for cancer risk.

    Science.gov (United States)

    Huber, Wolfgang W; Parzefall, Wolfram

    2005-01-01

    Enzymes of xenobiotic metabolism are involved in the activation and detoxification of carcinogens and can play a pivotal role in the susceptibility of individuals toward chemically induced cancer. Differences in such susceptibility are often related to genetically predetermined enzyme polymorphisms but may also be caused by enzyme induction or inhibition through environmental factors or in the frame of chemopreventive intervention. In this context, coffee consumption, as an important lifestyle factor, has been under thorough investigation. Whereas the data on a potential procarcinogenic effect in some organs remained inconclusive, epidemiology has clearly revealed coffee drinkers to be at a lower risk of developing cancers of the colon and the liver and possibly of several other organs. The underlying mechanisms of such chemoprotection, modifications of xenobiotic metabolism in particular, were further investigated in rodent and in vitro models, as a result of which several individual chemoprotectants out of the >1000 constituents of coffee were identified as well as some strongly metabolized individual carcinogens against which they specifically protected. This chapter discusses the chemoprotective effects of several coffee components and whole coffee in association with modifications of the usually protective glutathione-S-transferase (GST) and the more ambivalent N-acetyltransferase (NAT). A key role is played by kahweol and cafestol (K/C), two diterpenic constituents of the unfiltered beverage that were found to reduce mutagenesis/tumorigenesis by strongly metabolized compounds, such as 2-amino-1-methyl-6-phenylimidazo-[4,5-b]pyridine, 7,12-dimethylbenz[a]anthracene, and aflatoxin B(1), and to cause various modifications of xenobiotic metabolism that were overwhelmingly beneficial, including induction of GST and inhibition of NAT. Other coffee components such as polyphenols and K/C-free coffee are also capable of increasing GST and partially of inhibiting NAT

  14. The histone acetyltransferase GcnE (GCN5) plays a central role in the regulation of Aspergillus asexual development.

    Science.gov (United States)

    Cánovas, David; Marcos, Ana T; Gacek, Agnieszka; Ramos, María S; Gutiérrez, Gabriel; Reyes-Domínguez, Yazmid; Strauss, Joseph

    2014-08-01

    Acetylation of histones is a key regulatory mechanism of gene expression in eukaryotes. GcnE is an acetyltransferase of Aspergillus nidulans involved in the acetylation of histone H3 at lysine 9 and lysine 14. Previous works have demonstrated that deletion of gcnE results in defects in primary and secondary metabolism. Here we unveil the role of GcnE in development and show that a ∆gcnE mutant strain has minor growth defects but is impaired in normal conidiophore development. No signs of conidiation were found after 3 days of incubation, and immature and aberrant conidiophores were found after 1 week of incubation. Centroid linkage clustering and principal component (PC) analysis of transcriptomic data suggest that GcnE occupies a central position in Aspergillus developmental regulation and that it is essential for inducing conidiation genes. GcnE function was found to be required for the acetylation of histone H3K9/K14 at the promoter of the master regulator of conidiation, brlA, as well as at the promoters of the upstream developmental regulators of conidiation flbA, flbB, flbC, and flbD (fluffy genes). However, analysis of the gene expression of brlA and the fluffy genes revealed that the lack of conidiation originated in a complete absence of brlA expression in the ∆gcnE strain. Ectopic induction of brlA from a heterologous alcA promoter did not remediate the conidiation defects in the ∆gcnE strain, suggesting that additional GcnE-mediated mechanisms must operate. Therefore, we conclude that GcnE is the only nonessential histone modifier with a strong role in fungal development found so far.

  15. No evidence for role of extracellular choline-acetyltransferase in generation of gamma oscillations in rat hippocampal slices in vitro.

    Science.gov (United States)

    Hollnagel, J O; ul Haq, R; Behrens, C J; Maslarova, A; Mody, I; Heinemann, U

    2015-01-22

    Acetylcholine (ACh) is well known to induce persistent γ-oscillations in the hippocampus when applied together with physostigmine, an inhibitor of the ACh degrading enzyme acetylcholinesterase (AChE). Here we report that physostigmine alone can also dose-dependently induce γ-oscillations in rat hippocampal slices. We hypothesized that this effect was due to the presence of choline in the extracellular space and that this choline is taken up into cholinergic fibers where it is converted to ACh by the enzyme choline-acetyltransferase (ChAT). Release of ACh from cholinergic fibers in turn may then induce γ-oscillations. We therefore tested the effects of the choline uptake inhibitor hemicholinium-3 (HC-3) on persistent γ-oscillations either induced by physostigmine alone or by co-application of ACh and physostigmine. We found that HC-3 itself did not induce γ-oscillations and also did not prevent physostigmine-induced γ-oscillation while washout of physostigmine and ACh-induced γ-oscillations was accelerated. It was recently reported that ChAT might also be present in the extracellular space (Vijayaraghavan et al., 2013). Here we show that the effect of physostigmine was prevented by the ChAT inhibitor (2-benzoylethyl)-trimethylammonium iodide (BETA) which could indicate extracellular synthesis of ACh. However, when we tested for effects of extracellularly applied acetyl-CoA, a substrate of ChAT for synthesis of ACh, physostigmine-induced γ-oscillations were attenuated. Together, these findings do not support the idea that ACh can be synthesized by an extracellularly located ChAT. PMID:25453770

  16. Characterization of N-acetyltransferase 1 and 2 polymorphisms and haplotype analysis for inflammatory bowel disease and sporadic colorectal carcinoma

    Directory of Open Access Journals (Sweden)

    Cobbs Gary A

    2007-05-01

    Full Text Available Abstract Background N-acetyltransferase 1 (NAT1 and 2 (NAT2 are polymorphic isoenzymes responsible for the metabolism of numerous drugs and carcinogens. Acetylation catalyzed by NAT1 and NAT2 are important in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. Inflammatory bowel diseases (IBD consist of Crohn's disease (CD and ulcerative colitis (UC, both are associated with increased colorectal cancer (CRC risk. We hypothesized that NAT1 and/or NAT2 polymorphisms contribute to the increased cancer evident in IBD. Methods A case control study was performed with 729 Caucasian participants, 123 CRC, 201 CD, 167 UC, 15 IBD dysplasia/cancer and 223 controls. NAT1 and NAT2 genotyping were performed using Taqman based techniques. Eight single nucleotide polymorphisms (SNPs were characterized for NAT1 and 7 SNPs for NAT2. Haplotype frequencies were estimated using an Expectation-Maximization (EM method. Disease groups were compared to a control group for the frequencies at each individual SNP separately. The same groups were compared for the frequencies of NAT1 and NAT2 haplotypes and deduced NAT2 phenotypes. Results No statistically significant differences were found for any comparison. Strong linkage disequilibrium was present among both the NAT1 SNPs and the NAT2 SNPs. Conclusion This study did not demonstrate an association between NAT1 and NAT2 polymorphisms and IBD or sporadic CRC, although power calculations indicate this study had sufficient sample size to detect differences in frequency as small as 0.05 to 0.15 depending on SNP or haplotype.

  17. Cloning and characterization of the serotonin N-acetyltransferase-2 gene (SNAT2) in rice (Oryza sativa).

    Science.gov (United States)

    Byeon, Yeong; Lee, Hyoung Yool; Back, Kyoungwhan

    2016-09-01

    The penultimate enzyme in melatonin synthesis is serotonin N-acetyltransferase (SNAT), which exists as a single copy in mammals and plants. Our recent studies of the Arabidopsis snat-knockout mutant and SNAT RNAi rice (Oryza sativa) plants predicted the presence of at least one other SNAT isogene in plants; that is, the snat-knockout mutant of Arabidopsis and the SNAT RNAi rice plants still produced melatonin, even in the absence or the suppression of SNAT expression. Here, we report a molecular cloning of an SNAT isogene (OsSNAT2) from rice. The mature amino acid sequences of SNAT proteins indicated that OsSNAT2 and OsSNAT1 proteins had 39% identity values and 60% similarity. The Km and Vmax values of the purified recombinant OsSNAT2 were 371 μm and 4700 pmol/min/mg protein, respectively; the enzyme's optimal activity temperature was 45°C. Confocal microscopy showed that the OsSNAT2 protein was localized to both the cytoplasm and chloroplasts. The in vitro enzyme activity of OsSNAT2 was severely inhibited by melatonin, but the activities of sheep SNAT (OaSNAT) and rice OsSNAT1 proteins were not. The enzyme activity of OsSNAT2 was threefold higher than that of OsSNAT1, but 232-fold lower than that of OaSNAT. The OsSNAT1 and OsSNAT2 transcripts were similarly suppressed in rice leaves during the melatonin induction after cadmium treatment. Phylogenetic analyses indicated that OsSNAT1 and OsSNAT2 are distantly related, suggesting that they evolved independently from Cyanobacteria prior to the endosymbiosis event. PMID:27121038

  18. Spt-Ada-Gcn5-Acetyltransferase (SAGA Complex in Plants: Genome Wide Identification, Evolutionary Conservation and Functional Determination.

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    Rakesh Srivastava

    Full Text Available The recruitment of RNA polymerase II on a promoter is assisted by the assembly of basal transcriptional machinery in eukaryotes. The Spt-Ada-Gcn5-Acetyltransferase (SAGA complex plays an important role in transcription regulation in eukaryotes. However, even in the advent of genome sequencing of various plants, SAGA complex has been poorly defined for their components and roles in plant development and physiological functions. Computational analysis of Arabidopsis thaliana and Oryza sativa genomes for SAGA complex resulted in the identification of 17 to 18 potential candidates for SAGA subunits. We have further classified the SAGA complex based on the conserved domains. Phylogenetic analysis revealed that the SAGA complex proteins are evolutionary conserved between plants, yeast and mammals. Functional annotation showed that they participate not only in chromatin remodeling and gene regulation, but also in different biological processes, which could be indirect and possibly mediated via the regulation of gene expression. The in silico expression analysis of the SAGA components in Arabidopsis and O. sativa clearly indicates that its components have a distinct expression profile at different developmental stages. The co-expression analysis of the SAGA components suggests that many of these subunits co-express at different developmental stages, during hormonal interaction and in response to stress conditions. Quantitative real-time PCR analysis of SAGA component genes further confirmed their expression in different plant tissues and stresses. The expression of representative salt, heat and light inducible genes were affected in mutant lines of SAGA subunits in Arabidopsis. Altogether, the present study reveals expedient evidences of involvement of the SAGA complex in plant gene regulation and stress responses.

  19. Enteric plexuses of two choline-acetyltransferase transgenic mouse lines: chemical neuroanatomy of the fluorescent protein-expressing nerve cells.

    Science.gov (United States)

    Wilhelm, Márta; Lawrence, J Josh; Gábriel, Robert

    2015-02-01

    We studied cholinergic circuit elements in the enteric nervous system (ENS) of two distinct transgenic mouse lines in which fluorescent protein expression was driven by the choline-acetyltransferase (ChAT) promoter. In the first mouse line, green fluorescent protein was fused to the tau gene. This construct allowed the visualization of the fiber tracts and ganglia, however the nerve cells were poorly resolved. In the second mouse line (ChATcre-YFP), CRE/loxP recombination yielded cytosolic expression of yellow fluorescent protein (YFP). In these preparations the morphology of enteric neurons could be well studied. We also determined the neurochemical identity of ENS neurons in muscular and submucous layers using antibodies against YFP, calretinin (CALR), calbindin (CALB), and vasoactive intestinal peptide (VIP). Confocal microscopic imaging was used to visualize fluorescently-conjugated secondary antibodies. In ChATcre-YFP preparations, YFP was readily apparent in somatodendritic regions of ENS neurons. In the myenteric plexus, YFP/CALR/VIP staining revealed that 34% of cholinergic cells co-labeled with CALR. Few single-stained CR-positive cells were observed. Neither YFP nor CALR co-localized with VIP. In GFP/CALB/CALR staining, all co-localization combinations were represented. In the submucosal plexus, YFP/CALR/VIP staining revealed discrete neuronal populations. However, in separate preparations, double labeling was observed for YFP/CALR and CALR/VIP. In YFP/CALR/CALB staining, all combinations of double staining and triple labeling were verified. In conclusion, the neurochemical coding of ENS neurons in these mouse lines is consistent with many observations in non-transgenic animals. Thus, they provide useful tools for physiological and pharmacological studies on distinct neurochemical subtypes of ENS neurons. PMID:25592616

  20. Epigenetic regulation of proliferation and invasion in hepatocellular carcinoma cells by CBP/p300 histone acetyltransferase activity.

    Science.gov (United States)

    Inagaki, Yuji; Shiraki, Katsuya; Sugimoto, Kazushi; Yada, Takazumi; Tameda, Masahiko; Ogura, Suguru; Yamamoto, Norihiko; Takei, Yoshiyuki; Ito, Masaaki

    2016-02-01

    Altered epigenetic control of gene expression plays a substantial role in tumor development and progression. Accumulating studies suggest that somatic mutations of CREB binding proteins (CBP)/p300 occur in some cancer cells. CBP/p300 possess histone acetyltransferase (HAT) activity, and are involved in many cellular processes. In this study, we investigated the expression and functional role of CBP/p300 in hepatocellular carcinoma (HCC) using the specific inhibitor C646 of CBP/p300 HAT activity. We examined its effect on several apoptosis-related proteins and invasion-related genes. The results showed that CBP/p300 were highly expressed in HCC tissues and that expression of p300, but not of CBP, was strongly correlated with the malignant character of HCC. C646 inhibited proliferation of HCC cell lines in a dose dependent manner. C646 significantly augmented TRAIL-induced apoptotic sensitivity, which was accompanied by reduced levels of survivin, in HepG2, HLE and SK-HEP1 cells. C646 significantly inhibited invasion of Huh7, HLE and SK-HEP1 cells. The level of matrix metallopeptidase 15 (MMP15) mRNA expression was significantly reduced, whereas the level of laminin alpha 3 (LAMA3) and secreted phosphoprotein 1 (SPP1) mRNA expression was significantly increased in Huh7 cells following exposure to C646. In conclusion, our results suggest that CBP/p300 HAT activity has an important role in malignant transformation, proliferation, apoptotic sensitivity and invasion in HCC. CBP/p300 could be a promising therapeutic target in HCC. PMID:26676548

  1. Valproic acid exposure decreases Cbp/p300 protein expression and histone acetyltransferase activity in P19 cells.

    Science.gov (United States)

    Lamparter, Christina L; Winn, Louise M

    2016-09-01

    The teratogenicity of the antiepileptic drug valproic acid (VPA) is well established and its inhibition of histone deacetylases (HDAC) is proposed as an initiating factor. Recently, VPA-mediated HDAC inhibition was demonstrated to involve transcriptional downregulation of histone acetyltransferases (HATs), which was proposed to compensate for the increased acetylation resulting from HDAC inhibition. Cbp and p300 are HATs required for embryonic development and deficiencies in either are associated with congenital malformations and embryolethality. The objective of the present study was to characterize Cbp/p300 following VPA exposure in P19 cells. Consistent with previous studies, exposure to 5mM VPA over 24h induced a moderate decrease in Cbp/p300 mRNA, which preceded a strong decrease in total cellular protein mediated by ubiquitin-proteasome degradation. Nuclear Cbp/p300 protein was also decreased following VPA exposure, although to a lesser extent. Total cellular and nuclear p300 HAT activity was reduced proportionately to p300 protein levels, however while total cellular HAT activity also decreased, nuclear HAT activity was unaffected. Using the Cbp/p300 HAT inhibitor C646, we demonstrated that HAT inhibition similarly affected many of the same endpoints as VPA, including increased reactive oxygen species and caspase-3 cleavage, the latter of which could be attenuated by pre-treatment with the antioxidant catalase. C646 exposure also decreased NF-κB/p65 protein, which was not due to reduced mRNA and was not attenuated with catalase pre-treatment. This study provides support for an adaptive HAT response following VPA exposure and suggests that reduced Cbp/p300 HAT activity could contribute to VPA-mediated alterations. PMID:27381264

  2. Histone-modifying enzymes, histone modifications and histone chaperones in nucleosome assembly: Lessons learned from Rtt109 histone acetyltransferases.

    Science.gov (United States)

    Dahlin, Jayme L; Chen, Xiaoyue; Walters, Michael A; Zhang, Zhiguo

    2015-01-01

    During DNA replication, nucleosomes ahead of replication forks are disassembled to accommodate replication machinery. Following DNA replication, nucleosomes are then reassembled onto replicated DNA using both parental and newly synthesized histones. This process, termed DNA replication-coupled nucleosome assembly (RCNA), is critical for maintaining genome integrity and for the propagation of epigenetic information, dysfunctions of which have been implicated in cancers and aging. In recent years, it has been shown that RCNA is carefully orchestrated by a series of histone modifications, histone chaperones and histone-modifying enzymes. Interestingly, many features of RCNA are also found in processes involving DNA replication-independent nucleosome assembly like histone exchange and gene transcription. In yeast, histone H3 lysine K56 acetylation (H3K56ac) is found in newly synthesized histone H3 and is critical for proper nucleosome assembly and for maintaining genomic stability. The histone acetyltransferase (HAT) regulator of Ty1 transposition 109 (Rtt109) is the sole enzyme responsible for H3K56ac in yeast. Much research has centered on this particular histone modification and histone-modifying enzyme. This Critical Review summarizes much of our current understanding of nucleosome assembly and highlights many important insights learned from studying Rtt109 HATs in fungi. We highlight some seminal features in nucleosome assembly conserved in mammalian systems and describe some of the lingering questions in the field. Further studying fungal and mammalian chromatin assembly may have important public health implications, including deeper understandings of human cancers and aging as well as the pursuit of novel anti-fungal therapies.

  3. Mechanism of action of peptidoglycan O-acetyltransferase B involves a Ser-His-Asp catalytic triad.

    Science.gov (United States)

    Moynihan, Patrick J; Clarke, Anthony J

    2014-10-01

    The O-acetylation of the essential cell wall polymer peptidoglycan is essential in many bacteria for their integrity and survival, and it is catalyzed by peptidoglycan O-acetlytransferase B (PatB). Using PatB from Neisseria gonorrhoeae as the model, we have shown previously that the enzyme has specificity for polymeric muropeptides that possess tri- and tetrapeptide stems and that rates of reaction increase with increasing degrees of polymerization. Here, we present the catalytic mechanism of action of PatB, the first to be described for an O-acetyltransferase of any bacterial exopolysaccharide. The influence of pH on PatB activity was investigated, and pKa values of 6.4-6.45 and 6.25-6.35 for the enzyme-substrate complex (kcat vs pH) and the free enzyme (kcat·KM(-1) vs pH), respectively, were determined for the respective cosubstrates. The enzyme is partially inactivated by sulfonyl fluorides but not by EDTA, suggesting the participation of a serine residue in its catalytic mechanism. Alignment of the known and hypothetical PatB amino acid sequences identified Ser133, Asp302, and His305 as three invariant amino acid residues that could potentially serve as a catalytic triad. Replacement of Asp302 with Ala resulted in an enzyme with less than 20% residual activity, whereas activity was barely detectable with (His305 → Ala)PatB and (Ser133 → Ala)PatB was totally inactive. The reaction intermediate of the transferase reaction involving acetyl- and propionyl-acyl donors was trapped on both the wild-type and (Asp302 → Ala) enzymes and LC-MS/MS analysis of tryptic peptides identified Ser133 as the catalytic nucleophile. A transacetylase mechanism is proposed based on the mechanism of action of serine esterases. PMID:25215566

  4. Conversion of deoxynivalenol to 3-acetyldeoxynivalenol in barley-derived fuel ethanol co-products with yeast expressing trichothecene 3-O-acetyltransferases

    Directory of Open Access Journals (Sweden)

    Brooks Wynse S

    2011-09-01

    Full Text Available Abstract Background The trichothecene mycotoxin deoxynivalenol (DON may be concentrated in distillers dried grains with solubles (DDGS; a co-product of fuel ethanol fermentation when grain containing DON is used to produce fuel ethanol. Even low levels of DON (≤ 5 ppm in DDGS sold as feed pose a significant threat to the health of monogastric animals. New and improved strategies to reduce DON in DDGS need to be developed and implemented to address this problem. Enzymes known as trichothecene 3-O-acetyltransferases convert DON to 3-acetyldeoxynivalenol (3ADON, and may reduce its toxicity in plants and animals. Results Two Fusarium trichothecene 3-O-acetyltransferases (FgTRI101 and FfTRI201 were cloned and expressed in yeast (Saccharomyces cerevisiae during a series of small-scale ethanol fermentations using barley (Hordeum vulgare. DON was concentrated 1.6 to 8.2 times in DDGS compared with the starting ground grain. During the fermentation process, FgTRI101 converted 9.2% to 55.3% of the DON to 3ADON, resulting in DDGS with reductions in DON and increases in 3ADON in the Virginia winter barley cultivars Eve, Thoroughbred and Price, and the experimental line VA06H-25. Analysis of barley mashes prepared from the barley line VA04B-125 showed that yeast expressing FfTRI201 were more effective at acetylating DON than those expressing FgTRI101; DON conversion for FfTRI201 ranged from 26.1% to 28.3%, whereas DON conversion for FgTRI101 ranged from 18.3% to 21.8% in VA04B-125 mashes. Ethanol yields were highest with the industrial yeast strain Ethanol Red®, which also consumed galactose when present in the mash. Conclusions This study demonstrates the potential of using yeast expressing a trichothecene 3-O-acetyltransferase to modify DON during commercial fuel ethanol fermentation.

  5. The Bacillus anthracis arylamine N-acetyltransferase ((BACAN)NAT1) that inactivates sulfamethoxazole, reveals unusual structural features compared with the other NAT isoenzymes

    DEFF Research Database (Denmark)

    Pluvinage, Benjamin; Li de la Sierra-Gallay, Inés; Kubiak, Xavier Jean Philippe;

    2011-01-01

    Arylamine N-acetyltransferases (NATs) are xenobiotic-metabolizing enzymes that biotransform arylamine drugs. The Bacillus anthracis (BACAN)NAT1 enzyme affords increased resistance to the antibiotic sulfamethoxazole through its acetylation. We report the structure of (BACAN)NAT1. Unexpectedly......, endogenous coenzymeA was present in the active site. The structure suggests that, contrary to the other prokaryotic NATs, (BACAN)NAT1 possesses a 14-residue insertion equivalent to the "mammalian insertion", a structural feature considered unique to mammalian NATs. Moreover, (BACAN)NAT1 structure shows...

  6. C646, a Novel p300/CREB-Binding Protein-Specific Inhibitor of Histone Acetyltransferase, Attenuates Influenza A Virus Infection.

    Science.gov (United States)

    Zhao, Dongming; Fukuyama, Satoshi; Sakai-Tagawa, Yuko; Takashita, Emi; Shoemaker, Jason E; Kawaoka, Yoshihiro

    2016-03-01

    New strategies to develop novel broad-spectrum antiviral drugs against influenza virus infections are needed due to the emergence of antigenic variants and drug-resistant viruses. Here, we evaluated C646, a novel p300/CREB-binding protein-specific inhibitor of histone acetyltransferase (HAT), as an anti-influenza virus agent in vitro and in vivo and explored how C646 affects the viral life cycle and host response. Our studies highlight the value of targeting HAT activity for anti-influenza drug development. PMID:26711748

  7. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants

    Directory of Open Access Journals (Sweden)

    Silvia eTavares

    2015-02-01

    Full Text Available In higher plants cysteine biosynthesis is catalyzed by O-acetylserine(thiollyase (OASTL and represents the last step of the assimilatory sulfate reduction pathway. It is mainly regulated by provision of O-acetylserine (OAS, the nitrogen/carbon containing backbone for fixation of reduced sulfur. OAS is synthesized by Serine acetyltransferase (SERAT, which reversibly interacts with OASTL in the cysteine synthase complex (CSC. In this study we identify and characterize the SERAT protein family of the crop plant Vitis vinifera. The identified four members of the VvSERAT gene family are assigned to three distinct groups upon their sequence similarities to Arabidopsis SERATs. Expression of fluorescently labelled VvSERAT proteins uncover that the sub-cellular localization of VvSERAT1;1 and VvSERAT3;1 is the cytosol and that VvSERAT2;1 and VvSERAT2;2 localize in addition in plastids and mitochondria, respectively. The purified VvSERATs of group 1 and 2 have higher enzymatic activity than VvSERAT3;1, which display a characteristic C-terminal extension also present in AtSERAT3;1. VvSERAT1;1 and VvSERAT2;2 are evidenced to form the CSC. CSC formation activates VvSERAT2;2, by releasing CSC-associated VvSERAT2;2 from cysteine inhibition. Thus, subcellular distribution of SERAT isoforms and CSC formation in cytosol and mitochondria is conserved between Arabidopsis and grapevine. Surprisingly, VvSERAT2;1 lack the canonical C-terminal tail of plant SERATs, does not form the CSC and is almost insensitive to cysteine inhibition (IC50 = 1.9 mM cysteine. Upon sulfate depletion VvSERAT2;1 is strongly induced at the transcriptional level, while transcription of other VvSERATs is almost unaffected in sulfate deprived grapevine cell suspension cultures. Application of abiotic stresses to soil grown grapevine plants revealed isoform-specific induction of VvSERAT2;1 in leaves upon drought, whereas high light- or temperature- stress hardly trigger VvSERAT2;1 transcription.

  8. Effects of single nucleotide polymorphisms on human N-acetyltransferase 2 structure and dynamics by molecular dynamics simulation.

    Directory of Open Access Journals (Sweden)

    M Rajasekaran

    Full Text Available BACKGROUND: Arylamine N-acetyltransferase 2 (NAT2 is an important catalytic enzyme that metabolizes the carcinogenic arylamines, hydrazine drugs and chemicals. This enzyme is highly polymorphic in different human populations. Several polymorphisms of NAT2, including the single amino acid substitutions R64Q, I114T, D122N, L137F, Q145P, R197Q, and G286E, are classified as slow acetylators, whereas the wild-type NAT2 is classified as a fast acetylator. The slow acetylators are often associated with drug toxicity and efficacy as well as cancer susceptibility. The biological functions of these 7 mutations have previously been characterized, but the structural basis behind the reduced catalytic activity and reduced protein level is not clear. METHODOLOGY/PRINCIPAL FINDINGS: We performed multiple molecular dynamics simulations of these mutants as well as NAT2 to investigate the structural and dynamical effects throughout the protein structure, specifically the catalytic triad, cofactor binding site, and the substrate binding pocket. None of these mutations induced unfolding; instead, their effects were confined to the inter-domain, domain 3 and 17-residue insert region, where the flexibility was significantly reduced relative to the wild-type. Structural effects of these mutations propagate through space and cause a change in catalytic triad conformation, cofactor binding site, substrate binding pocket size/shape and electrostatic potential. CONCLUSIONS/SIGNIFICANCE: Our results showed that the dynamical properties of all the mutant structures, especially in inter-domain, domain 3 and 17-residue insert region were affected in the same manner. Similarly, the electrostatic potential of all the mutants were altered and also the functionally important regions such as catalytic triad, cofactor binding site, and substrate binding pocket adopted different orientation and/or conformation relative to the wild-type that may affect the functions of the mutants

  9. Chemical and genetic blockade of HDACs enhances osteogenic differentiation of human adipose tissue-derived stem cells by oppositely affecting osteogenic and adipogenic transcription factors

    Energy Technology Data Exchange (ETDEWEB)

    Maroni, Paola [Istituto Ortopedico Galeazzi, Milano (Italy); Brini, Anna Teresa [Istituto Ortopedico Galeazzi, Milano (Italy); Dipartimento di Scienze Biomediche, Chirurgiche ed Odontoiatriche, Universita degli Studi di Milano, Milano (Italy); Arrigoni, Elena [Dipartimento di Scienze Biomediche, Chirurgiche ed Odontoiatriche, Universita degli Studi di Milano, Milano (Italy); Girolamo, Laura de [Istituto Ortopedico Galeazzi, Milano (Italy); Niada, Stefania [Istituto Ortopedico Galeazzi, Milano (Italy); Dipartimento di Scienze Biomediche, Chirurgiche ed Odontoiatriche, Universita degli Studi di Milano, Milano (Italy); Matteucci, Emanuela; Bendinelli, Paola [Dipartimento di Scienze Biomediche per la Salute, Molecular Pathology Laboratory, Universita degli Studi di Milano, Milano (Italy); Desiderio, Maria Alfonsina, E-mail: a.desiderio@unimi.it [Dipartimento di Scienze Biomediche per la Salute, Molecular Pathology Laboratory, Universita degli Studi di Milano, Milano (Italy)

    2012-11-16

    Highlights: Black-Right-Pointing-Pointer Acetylation affected hASCs osteodifferentiation through Runx2-PPAR{gamma}. Black-Right-Pointing-Pointer HDACs knocking-down favoured the commitment effect of osteogenic medium. Black-Right-Pointing-Pointer HDACs silencing early activated Runx2 and ALP. Black-Right-Pointing-Pointer PPAR{gamma} reduction and calcium/collagen deposition occurred later. Black-Right-Pointing-Pointer Runx2/PPAR{gamma} target genes were modulated in line with HDACs role in osteo-commitment. -- Abstract: The human adipose-tissue derived stem/stromal cells (hASCs) are an interesting source for bone-tissue engineering applications. Our aim was to clarify in hASCs the role of acetylation in the control of Runt-related transcription factor 2 (Runx2) and Peroxisome proliferator activated receptor (PPAR) {gamma}. These key osteogenic and adipogenic transcription factors are oppositely involved in osteo-differentiation. The hASCs, committed or not towards bone lineage with osteoinductive medium, were exposed to HDACs chemical blockade with Trichostatin A (TSA) or were genetically silenced for HDACs. Alkaline phosphatase (ALP) and collagen/calcium deposition, considered as early and late osteogenic markers, were evaluated concomitantly as index of osteo-differentiation. TSA pretreatment, useful experimental protocol to analyse pan-HDAC-chemical inhibition, and switch to osteogenic medium induced early-osteoblast maturation gene Runx2, while transiently decreased PPAR{gamma} and scarcely affected late-differentiation markers. Time-dependent effects were observed after knocking-down of HDAC1 and 3: Runx2 and ALP underwent early activation, followed by late-osteogenic markers increase and by PPAR{gamma}/ALP activity diminutions mostly after HDAC3 silencing. HDAC1 and 3 genetic blockade increased and decreased Runx2 and PPAR{gamma} target genes, respectively. Noteworthy, HDACs knocking-down favoured the commitment effect of osteogenic medium. Our results reveal

  10. Adipogenic changes of hepatocytes in a high-fat diet-induced fatty liver mice model and non-alcoholic fatty liver disease patients.

    Science.gov (United States)

    Pan, Xiaoli; Wang, Pei; Luo, Jinzhuo; Wang, Zhijun; Song, Yuhu; Ye, Jin; Hou, Xiaohua

    2015-04-01

    adipogenic changes in hepatocytes are involved in pathogenesis of NAFLD. PMID:25138963

  11. The Methionine Transamination Pathway Controls Hepatic Glucose Metabolism through Regulation of the GCN5 Acetyltransferase and the PGC-1α Transcriptional Coactivator.

    Science.gov (United States)

    Tavares, Clint D J; Sharabi, Kfir; Dominy, John E; Lee, Yoonjin; Isasa, Marta; Orozco, Jose M; Jedrychowski, Mark P; Kamenecka, Theodore M; Griffin, Patrick R; Gygi, Steven P; Puigserver, Pere

    2016-05-13

    Methionine is an essential sulfur amino acid that is engaged in key cellular functions such as protein synthesis and is a precursor for critical metabolites involved in maintaining cellular homeostasis. In mammals, in response to nutrient conditions, the liver plays a significant role in regulating methionine concentrations by altering its flux through the transmethylation, transsulfuration, and transamination metabolic pathways. A comprehensive understanding of how hepatic methionine metabolism intersects with other regulatory nutrient signaling and transcriptional events is, however, lacking. Here, we show that methionine and derived-sulfur metabolites in the transamination pathway activate the GCN5 acetyltransferase promoting acetylation of the transcriptional coactivator PGC-1α to control hepatic gluconeogenesis. Methionine was the only essential amino acid that rapidly induced PGC-1α acetylation through activating the GCN5 acetyltransferase. Experiments employing metabolic pathway intermediates revealed that methionine transamination, and not the transmethylation or transsulfuration pathways, contributed to methionine-induced PGC-1α acetylation. Moreover, aminooxyacetic acid, a transaminase inhibitor, was able to potently suppress PGC-1α acetylation stimulated by methionine, which was accompanied by predicted alterations in PGC-1α-mediated gluconeogenic gene expression and glucose production in primary murine hepatocytes. Methionine administration in mice likewise induced hepatic PGC-1α acetylation, suppressed the gluconeogenic gene program, and lowered glycemia, indicating that a similar phenomenon occurs in vivo These results highlight a communication between methionine metabolism and PGC-1α-mediated hepatic gluconeogenesis, suggesting that influencing methionine metabolic flux has the potential to be therapeutically exploited for diabetes treatment.

  12. Structure-based molecular design for thermostabilization of N-acetyltransferase Mpr1 involved in a novel pathway of L-arginine synthesis in yeast.

    Science.gov (United States)

    Nasuno, Ryo; Hirase, Saeka; Norifune, Saki; Watanabe, Daisuke; Takagi, Hiroshi

    2016-02-01

    Previously, N-Acetyltransferase Mpr1 was suggested to be involved in a novel pathway of L-arginine biosynthesis in yeast. Our recent crystallographic analysis demonstrated that the overall structure of Mpr1 is a typical folding among proteins in the Gcn5-related N-acetyltransferase superfamily, and also provided clues to the design of mutations for improvement of the enzymatic functions. Here, we constructed new stable variants, Asn203Lys- and Asn203Arg-Mpr1, which exhibited 2.4-fold and 2.2-fold longer activity half-lives than wild-type Mpr1, respectively, by structure-based molecular design. The replacement of Asn203 with a basic amino acid was suggested to stabilize α-helix 2, which is important for the Mpr1 structure, probably by neutralizing its dipole. In addition, the combination of two amino acid substitutions at positions 65 and 203 in Mpr1, Phe65Leu, which was previously isolated by the screening from PCR random mutagenesis library of MPR1, and Asn203Lys or Asn203Arg, led to further stabilization of Mpr1. Our growth assay suggests that overexpression of the stable Mpr1 variants increase L-arginine synthesis in yeast cells. Our finding is the first report on the rational engineering of Mpr1 for thermostabilization and could be useful in the construction of new yeast strains with higher L-arginine synthetic activity and also improved fermentation ability.

  13. Delphinidin, a specific inhibitor of histone acetyltransferase, suppresses inflammatory signaling via prevention of NF-{kappa}B acetylation in fibroblast-like synoviocyte MH7A cells

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Ah-Reum; Yoo, Jung-Yoon; Choi, KyungChul [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Lee, Mee-Hee [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University, College of Medicine, Seoul (Korea, Republic of); Lee, Yoo-Hyun [Department of Food Science and Nutrition, The University of Suwon, Kyunggi-do (Korea, Republic of); Lee, Jeongmin [Department of Medical Nutrition, Kyung Hee University, Kyunggi-do (Korea, Republic of); Jun, Woojin [Department of Food and Nutrition, Chonnam National University, Gwangju (Korea, Republic of); Kim, Sunoh, E-mail: sunoh@korea.ac.kr [Jeollanamdo Institute of Natural Resources Research, Jeonnam (Korea, Republic of); Yoon, Ho-Geun, E-mail: yhgeun@yuhs.ac [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University, College of Medicine, Seoul (Korea, Republic of)

    2011-07-08

    Highlights: {yields} Delphinidin is a novel inhibitor of p300/CBP histone acetyltransferase. {yields} Delphinidin prevents the hyperacetylation of p65 by inhibiting the HAT activity of p300/CBP. {yields} Delphinidin efficiently suppresses the expression of inflammatory cytokines in MH7A cells via hypoacetylation of NF-{kappa}B. {yields} Delphinidin inhibits cytokine release in the Jurkat T lymphocyte cell line. -- Abstract: Histone acetyltransferase (HAT) inhibitors (HATi) isolated from dietary compounds have been shown to suppress inflammatory signaling, which contributes to rheumatoid arthritis. Here, we identified a novel HATi in Punica granatum L. known as delphinidin (DP). DP did not affect the activity of other epigenetic enzymes (histone deacetylase, histone methyltransferase, or sirtuin1). DP specifically inhibited the HAT activities of p300/CBP. It also inhibited p65 acetylation in MH7A cells, a human rheumatoid arthritis synovial cell line. DP-induced hypoacetylation was accompanied by cytosolic accumulation of p65 and nuclear localization of IKB{alpha}. Accordingly, DP treatment inhibited TNF{alpha}-stimulated increases in NF-{kappa}B function and expression of NF-{kappa}B target genes in these cells. Importantly, DP suppressed lipopolysaccharide-induced pro-inflammatory cytokine expression in Jurkat T lymphocytes, demonstrating that HATi efficiently suppresses cytokine-mediated immune responses. Together, these results show that the HATi activity of DP counters anti-inflammatory signaling by blocking p65 acetylation and that this compound may be useful in preventing inflammatory arthritis.

  14. Delphinidin, a specific inhibitor of histone acetyltransferase, suppresses inflammatory signaling via prevention of NF-κB acetylation in fibroblast-like synoviocyte MH7A cells

    International Nuclear Information System (INIS)

    Highlights: → Delphinidin is a novel inhibitor of p300/CBP histone acetyltransferase. → Delphinidin prevents the hyperacetylation of p65 by inhibiting the HAT activity of p300/CBP. → Delphinidin efficiently suppresses the expression of inflammatory cytokines in MH7A cells via hypoacetylation of NF-κB. → Delphinidin inhibits cytokine release in the Jurkat T lymphocyte cell line. -- Abstract: Histone acetyltransferase (HAT) inhibitors (HATi) isolated from dietary compounds have been shown to suppress inflammatory signaling, which contributes to rheumatoid arthritis. Here, we identified a novel HATi in Punica granatum L. known as delphinidin (DP). DP did not affect the activity of other epigenetic enzymes (histone deacetylase, histone methyltransferase, or sirtuin1). DP specifically inhibited the HAT activities of p300/CBP. It also inhibited p65 acetylation in MH7A cells, a human rheumatoid arthritis synovial cell line. DP-induced hypoacetylation was accompanied by cytosolic accumulation of p65 and nuclear localization of IKBα. Accordingly, DP treatment inhibited TNFα-stimulated increases in NF-κB function and expression of NF-κB target genes in these cells. Importantly, DP suppressed lipopolysaccharide-induced pro-inflammatory cytokine expression in Jurkat T lymphocytes, demonstrating that HATi efficiently suppresses cytokine-mediated immune responses. Together, these results show that the HATi activity of DP counters anti-inflammatory signaling by blocking p65 acetylation and that this compound may be useful in preventing inflammatory arthritis.

  15. Crystal Structure of the Golgi-Associated Human Nα-Acetyltransferase 60 Reveals the Molecular Determinants for Substrate-Specific Acetylation.

    Science.gov (United States)

    Støve, Svein Isungset; Magin, Robert S; Foyn, Håvard; Haug, Bengt Erik; Marmorstein, Ronen; Arnesen, Thomas

    2016-07-01

    N-Terminal acetylation is a common and important protein modification catalyzed by N-terminal acetyltransferases (NATs). Six human NATs (NatA-NatF) contain one catalytic subunit each, Naa10 to Naa60, respectively. In contrast to the ribosome-associated NatA to NatE, NatF/Naa60 specifically associates with Golgi membranes and acetylates transmembrane proteins. To gain insight into the molecular basis for the function of Naa60, we developed an Naa60 bisubstrate CoA-peptide conjugate inhibitor, determined its X-ray structure when bound to CoA and inhibitor, and carried out biochemical experiments. We show that Naa60 adapts an overall fold similar to that of the catalytic subunits of ribosome-associated NATs, but with the addition of two novel elongated loops that play important roles in substrate-specific binding. One of these loops mediates a dimer to monomer transition upon substrate-specific binding. Naa60 employs a catalytic mechanism most similar to Naa50. Collectively, these data reveal the molecular basis for Naa60-specific acetyltransferase activity with implications for its Golgi-specific functions.

  16. 3D structure prediction of histone acetyltransferase (HAC proteins of the p300/CBP family and their interactome in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Amar Cemanovic

    2014-09-01

    Full Text Available Histone acetylation is an important posttranslational modification correlated with gene activation. In Arabidopsis thaliana the histone acetyltransferase (HAC proteins of the CBP family are homologous to animal p300/CREB (cAMP-responsive element-binding proteins, which are important histone acetyltransferases participating in many physiological processes, including proliferation, differentiation, and apoptosis. In this study the 3-D structure of all HAC protein subunits in Arabidopsis thaliana: HAC1, HAC2, HAC4, HAC5 and HAC12 is predicted by homology modeling and confirmed by Ramachandran plot analysis. The amino acid sequences HAC family members are highly similar to the sequences of the homologous human p300/CREB protein. Conservation of p300/CBP domains among the HAC proteins was examined further by sequence alignment and pattern search. The domains of p300/CBP required for the HAC function, such as PHD, TAZ and ZZ domains, are conserved in all HAC proteins. Interactome analysis revealed that HAC1, HAC5 and HAC12 proteins interact with S-adenosylmethionine-dependent methyltransferase domaincontaining protein that shows methyltransferase activity, suggesting an additional function of the HAC proteins. Additionally, HAC5 has a strong interaction value for the putative c-myb-like transcription factor MYB3R-4, which suggests that it also may have a function in regulation of DNA replication.

  17. Ethanol extract of lotus (Nelumbo nucifera) root exhibits an anti-adipogenic effect in human pre-adipocytes and anti-obesity and anti-oxidant effects in rats fed a high-fat diet.

    Science.gov (United States)

    You, Jeong Soon; Lee, Yun Ju; Kim, Kyoung Soo; Kim, Sung Hoon; Chang, Kyung Ja

    2014-03-01

    Lotus (Nelumbo Nucifera) root, a well-known medicinal plant in Asia, is reported to have various therapeutic benefits, including anti-diabetes, anti-hypertension, and anti-hyperlipidaemia. We hypothesized that the ethanol extract of lotus root (ELR) would exhibit an anti-adipogenic effect in human pre-adipocytes as well as anti-obesity and anti-oxidant effects in rats fed a high-fat diet. Treatment with ELR in human pre-adipocytes resulted in inhibition of lipid accumulation and attenuated expression of adipogenic transcription factors such as peroxisome proliferator-activated receptor gamma and adipocyte marker genes, such as glucose transporter 4 and leptin. Administration of ELR resulted in a significant decrease in relative weights of adipose tissues in rats fed a high-fat diet. Consumption of a high-fat diet resulted in an increase in serum total cholesterol (TC) and triglyceride (TG) levels; however, administration of ELR resulted in a decrease in the levels of TC and TG. Administration of ELR resulted in a decrease in the level of serum leptin and insulin. Administration of ELR in rats fed a high-fat diet resulted in a decrease in hepatic thiobarbituric acid reactive substance content, elevated by a high-fat diet and an increase in superoxide dismutase activity and hepatic glutathione content. These results suggest that lotus root exerts anti-oxidant and anti-obesity effects and could be used as a functional and nutraceutical ingredient in combatting obesity-related diseases.

  18. Phenotypic variability in 49 cases of ESCO2 mutations, including novel missense and codon deletion in the acetyltransferase domain, correlates with ESCO2 expression and establishes the clinical criteria for Roberts syndrome

    DEFF Research Database (Denmark)

    Vega, H; Trainer, A H; Gordillo, M;

    2010-01-01

    Roberts syndrome (RBS) and SC phocomelia are caused by mutations in ESCO2, which codes for an acetyltransferase involved in the regulation of sister chromatid cohesion. Of 26 mutations described to date, only one missense mutation has been reported and all others are predicted to be truncating mu...

  19. 人脂肪干细胞脂向分化中长非编码RNA的差异表达%Differentially expressed long non-coding RNAs in adipogenic differentiation of human adipose-derived stem cells

    Institute of Scientific and Technical Information of China (English)

    岳文峻; 王香梅; 张芹; 黄海华; 韦有万; 彭智

    2014-01-01

    BACKGROUND:The obesity has led to a plenty of diseases including hypertension, coronary heart disease, fatty liver, hyperlipidemia, and type 2 diabetes. Therefore, understanding the mechanism of adipocyte differentiation is of far-reaching significance to the prevention and treatment of obesity. For the current studies of the mechanism of adipocyte differentiation pay more attention to microRNA, rather than long non-coding RNAs (lncRNAs). OBJECTIVE:To obtain the lncRNAs whose fold change was apparent during adipogenic differentiation, and to further screen the lncRNAs that possibly play a crucial role in adipogenic differentiation for verification. METHODS:Subcutaneous fat was obtained from human abdomen. Adipose-derived stem cells were col ected using tissue culture method. The third passage of adipose-derived stem cells was used for adipogenic differentiation. Through microarray technology, the expression levels of lncRNAs and mRNA were analyzed at 0, 5 and 12 days in adipogenic differentiation. Combining with bioinformatics report, lncRNAs apparently presented fold change were screened and verified by qRT-PCR. RESULTS AND CONCLUSION:Fold change 1.5 (P<0.05) was considered as a criterion during adipogenic differentiation. The number of up-regulated lncRNAs was 748 for 5 days versus 0 day, 847 for 12 days versus 0 days, 593 for 12 days versus 5 days. At the same time, the down-regulated number was 828 for 5 days versus 0 day, 1 113 for 12 days versus 0 day, 750 for 12 days versus 5 days during adipogenic differentiation. In combination with bioinformatics analysis results, 3 of 28 lncRNAs were related to lipid metabolism:AK304548, BP216319 and DA852857, according to the standard that fold change in 0, 5 and 12 days was higher, and the target genes were known to be associated with adipogenesis-related genes. PCR results showed that the expression of AK304548 and BP216319 and its target gene presented an up-down trend, which is consistent with the microarray

  20. A novel method to quantify the activity of alcohol acetyltransferase Using a SnO2-based sensor of electronic nose.

    Science.gov (United States)

    Hu, Zhongqiu; Li, Xiaojing; Wang, Huxuan; Niu, Chen; Yuan, Yahong; Yue, Tianli

    2016-07-15

    Alcohol acetyltransferase (AATFase) extensively catalyzes the reactions of alcohols to acetic esters in microorganisms and plants. In this work, a novel method has been proposed to quantify the activity of AATFase using a SnO2-based sensor of electronic nose, which was determined on the basis of its higher sensitivity to the reducing alcohol than the oxidizing ester. The maximum value of the first-derivative of the signals from the SnO2-based sensor was therein found to be an eigenvalue of isoamyl alcohol concentration. Quadratic polynomial regression perfectly fitted the correlation between the eigenvalue and the isoamyl alcohol concentration. The method was used to determine the AATFase activity in this type of reaction by calculating the conversion rate of isoamyl alcohol. The proposed method has been successfully applied to determine the AATFase activity of a cider yeast strain. Compared with GC-MS, the method shows promises with ideal recovery and low cost. PMID:26948643

  1. Acetylation of retinal histones in diabetes increases inflammatory proteins: effects of minocycline and manipulation of histone acetyltransferase (HAT) and histone deacetylase (HDAC).

    Science.gov (United States)

    Kadiyala, Chandra Sekhar Rao; Zheng, Ling; Du, Yunpeng; Yohannes, Elizabeth; Kao, Hung-Ying; Miyagi, Masaru; Kern, Timothy S

    2012-07-27

    Histone acetylation was significantly increased in retinas from diabetic rats, and this acetylation was inhibited in diabetics treated with minocycline, a drug known to inhibit early diabetic retinopathy in animals. Histone acetylation and expression of inflammatory proteins that have been implicated in the pathogenesis of diabetic retinopathy were increased likewise in cultured retinal Müller glia grown in a diabetes-like concentration of glucose. Both the acetylation and induction of the inflammatory proteins in elevated glucose levels were significantly inhibited by inhibitors of histone acetyltransferase (garcinol and antisense against the histone acetylase, p300) or activators of histone deacetylase (theophylline and resveratrol) and were increased by the histone deacetylase inhibitor, suberolylanilide hydroxamic acid. We conclude that hyperglycemia causes acetylation of retinal histones (and probably other proteins) and that the acetylation contributes to the hyperglycemia-induced up-regulation of proinflammatory proteins and thereby to the development of diabetic retinopathy.

  2. Structures and functions of insect arylalkylamine N-acetyltransferase (iaaNAT; a key enzyme for physiological and behavioral switch in arthropods

    Directory of Open Access Journals (Sweden)

    Susumu eHiragaki

    2015-04-01

    Full Text Available The evolution of N-acetyltransfeases (NATs seems complex. Vertebrate arylalkylamine N-acetyltransferase (aaNAT has been extensively studied since it Leads to the synthesis of melatonin, a multifunctional neurohormone prevalent in photoreceptor cells, and is known as as a chemical token of the night. Melatonin also serves as a scavenger for reactive oxygen species. This is also true with invertebrates. NAT therefore has distinct functional implications in circadian function, as timezymes (aaNAT, and also xenobiotic reactions (arylamine NAT or simply NAT. NATs belong to a broader enzyme group, the GCN5-related N-acetyltransferase superfamily. Due to low sequence homology and a seemingly fast rate of structural differentiation, the nomenclature for NATs can be confusing. The advent of bioinformatics, however, has helped to classify this group of enzymes; vertebrates have two distinct subgroups, the timezyme type and the xenobiotic type, which has a wider substrate range including imidazolamine, pharmacological drugs, environmental toxicants and even histone. Insect aaNAT (iaaNAT form their own clade in the phylogeny, distinct from vertebrate aaNATs. Arthropods are unique, since the phylum has exoskeleton in which quinones derived from N-acetylated monoamines function in coupling chitin and arthropodins. Monoamine oxidase (MAO activity is limited in insects, but NAT-mediated degradation prevails. However, unexpectedly iaaNAT occurs not only among arthropods but also among basal deuterostomia, and is therefore more apomorphic. Our analyses illustrate that iaaNATs has unique physiological roles but at the same time it plays a role in a timezyme function, at least in photoperiodism. Photoperiodism has been considered as a function of circadian system but the detailed molecular mechanism is not well understood. We propose a molecular hypothesis for photoperiodism in Antheraea pernyi based on the transcription regulation of NAT interlocked by the

  3. N-acetyltransferase 2 (NAT2) gene polymorphism as a predisposing factor for phenytoin intoxication in tuberculous meningitis or tuberculoma patients having seizures - A pilot study

    Science.gov (United States)

    Adole, Prashant S.; Kharbanda, Parampreet S.; Sharma, Sadhna

    2016-01-01

    Background & objectives: Simultaneous administration of phenytoin and isoniazid (INH) in tuberculous meningitis (TBM) or tuberculoma patients with seizures results in higher plasma phenytoin level and thus phenytoin intoxication. N-acetyltransferase 2 (NAT2) enzyme catalyses two acetylation reactions in INH metabolism and NAT2 gene polymorphism leads to slow and rapid acetylators. The present study was aimed to evaluate the effect of allelic variants of N-acetyltransferase 2 (NAT2) gene as a predisposing factor for phenytoin toxicity in patients with TBM or tuberculoma having seizures, and taking INH and phenytoin simultaneously. Methods: Sixty patients with TBM or tuberculoma with seizures and taking INH and phenytoin simultaneously for a minimum period of seven days were included in study. Plasma phenytoin was measured by high performance liquid chromatography. NAT2 gene polymorphism was studied using restriction fragment length polymorphism and allele specific PCR. Results: The patients were grouped into those having phenytoin intoxication and those with normal phenytoin level, and also classified as rapid or slow acetylators by NAT2 genotyping. Genotypic analysis showed that of the seven SNPs (single nucleotide polymorphisms) of NAT2 gene studied, six mutations were found to be associated with phenytoin intoxication. For rs1041983 (C282T), rs1799929 (C481T), rs1799931 (G857A), rs1799930 (G590A), rs1208 (A803G) and rs1801280 (T341C) allelic variants, the proportion of homozygous mutant was higher in phenytoin intoxicated group than in phenytoin non-intoxicated group. Interpretation & conclusions: Homozygous mutant allele of NAT2 gene at 481site may act as a predisposing factor for phenytoin intoxication among TBM or tuberculoma patients having seizures. PMID:27488001

  4. Expression levels of the yeast alcohol acetyltransferase genes ATF1, Lg-ATF1, and ATF2 control the formation of a broad range of volatile esters.

    Science.gov (United States)

    Verstrepen, Kevin J; Van Laere, Stijn D M; Vanderhaegen, Bart M P; Derdelinckx, Guy; Dufour, Jean-Pierre; Pretorius, Isak S; Winderickx, Joris; Thevelein, Johan M; Delvaux, Freddy R

    2003-09-01

    Volatile aroma-active esters are responsible for the fruity character of fermented alcoholic beverages such as beer and wine. Esters are produced by fermenting yeast cells in an enzyme-catalyzed intracellular reaction. In order to investigate and compare the roles of the known Saccharomyces cerevisiae alcohol acetyltransferases, Atf1p, Atf2p and Lg-Atf1p, in volatile ester production, the respective genes were either deleted or overexpressed in a laboratory strain and a commercial brewing strain. Subsequently, the ester formation of the transformants was monitored by headspace gas chromatography and gas chromatography combined with mass spectroscopy (GC-MS). Analysis of the fermentation products confirmed that the expression levels of ATF1 and ATF2 greatly affect the production of ethyl acetate and isoamyl acetate. GC-MS analysis revealed that Atf1p and Atf2p are also responsible for the formation of a broad range of less volatile esters, such as propyl acetate, isobutyl acetate, pentyl acetate, hexyl acetate, heptyl acetate, octyl acetate, and phenyl ethyl acetate. With respect to the esters analyzed in this study, Atf2p seemed to play only a minor role compared to Atf1p. The atf1Delta atf2Delta double deletion strain did not form any isoamyl acetate, showing that together, Atf1p and Atf2p are responsible for the total cellular isoamyl alcohol acetyltransferase activity. However, the double deletion strain still produced considerable amounts of certain other esters, such as ethyl acetate (50% of the wild-type strain), propyl acetate (50%), and isobutyl acetate (40%), which provides evidence for the existence of additional, as-yet-unknown ester synthases in the yeast proteome. Interestingly, overexpression of different alleles of ATF1 and ATF2 led to different ester production rates, indicating that differences in the aroma profiles of yeast strains may be partially due to mutations in their ATF genes. PMID:12957907

  5. FA1 Induces Pro-Inflammatory and Anti-Adipogenic Pathways/Markers in Human Myotubes Established from Lean, Obese, and Type 2 Diabetic Subjects but Not Insulin Resistance

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Beck-Nielsen, Henning; Gaster, Michael

    2013-01-01

    /FA1 in insulin resistance and type 2 diabetes in human subjects, we studied the effects of chronic FA1 on the intermediary metabolism in myotubes established from lean, obese, and type 2 diabetic (T2D) subjects. Methods: Myotube cultures were established from lean and obese control subjects, and...... established from lean, obese, and T2D subjects. Instead, chronic FA1 exposure induced pro-inflammatory cytokines expression (IL-6 and CCL2) in association with reducing adipogenic markers (ADD1, AP2, CD36, and PPARg2) in myotubes. Consistent with this observation, addition of FA1 to cultured myotubes was show...... to significantly inhibit their differentiation into adipocyte. Conclusion: Our results exclude direct effects of FA1 on glucose and lipid metabolism in cultured myotubes established from lean, obese, and T2D subjects. Therefore, the pathogenesis of FA1-induced IR might mainly be mediated via the FA1...

  6. Genome-wide characterisation of the Gcn5 histone acetyltransferase in budding yeast during stress adaptation reveals evolutionarily conserved and diverged roles

    Directory of Open Access Journals (Sweden)

    Brodin David

    2010-03-01

    Full Text Available Abstract Background Gcn5 is a transcriptional coactivator with histone acetyltransferase activity that is conserved with regard to structure as well as its histone substrates throughout the eukaryotes. Gene regulatory networks within cells are thought to be evolutionarily diverged. The use of evolutionarily divergent yeast species, such as S. cerevisiae and S. pombe, which can be studied under similar environmental conditions, provides an opportunity to examine the interface between conserved regulatory components and their cellular applications in different organisms. Results We show that Gcn5 is important for a common set of stress responses in evolutionarily diverged yeast species and that the activity of the conserved histone acetyltransferase domain is required. We define a group of KCl stress response genes in S. cerevisiae that are specifically dependent on Gcn5. Gcn5 is localised to many Gcn5-dependent genes including Gcn5 repressed targets such as FLO8. Gcn5 regulates divergent sets of KCl responsive genes in S. cerevisiae and S. pombe. Genome-wide localization studies showed a tendency for redistribution of Gcn5 during KCl stress adaptation in S. cerevisiae from short genes to the transcribed regions of long genes. An analogous redistribution was not observed in S. pombe. Conclusions Gcn5 is required for the regulation of divergent sets of KCl stress-response genes in S. cerevisiae and S. pombe even though it is required a common group of stress responses, including the response to KCl. Genes that are physically associated with Gcn5 require its activity for their repression or activation during stress adaptation, providing support for a role of Gcn5 as a corepressor as well as a coactivator. The tendency of Gcn5 to re-localise to the transcribed regions of long genes during KCl stress adaptation suggests that Gcn5 plays a specific role in the expression of long genes under adaptive conditions, perhaps by regulating transcriptional

  7. Differences in Enzymatic Properties of the Saccharomyces kudriavzevii and Saccharomyces uvarum Alcohol Acetyltransferases and Their Impact on Aroma-Active Compounds Production

    Science.gov (United States)

    Stribny, Jiri; Querol, Amparo; Pérez-Torrado, Roberto

    2016-01-01

    Higher alcohols and acetate esters belong to the most important yeast secondary metabolites that significantly contribute to the overall flavor and aroma profile of fermented products. In Saccharomyces cerevisiae, esterification of higher alcohols is catalyzed mainly by the alcohol acetyltransferases encoded by genes ATF1 and ATF2. Previous investigation has shown other Saccharomyces species, e.g., S. kudriavzevii and S. uvarum, to vary in aroma-active higher alcohols and acetate esters formation when compared to S. cerevisiae. Here, we aimed to analyze the enzymes encoded by the ATF1 and ATF2 genes from S. kudriavzevii (SkATF1, SkATF2) and S. uvarum (SuATF1, SuATF2). The heterologous expression of the individual ATF1 and ATF2 genes in a host S. cerevisiae resulted in the enhanced production of several higher alcohols and acetate esters. Particularly, an increase of 2-phenylethyl acetate production by the strains that harbored ATF1 and ATF2 genes from S. kudriavzevii and S. uvarum was observed. When grown with individual amino acids as the nitrogen source, the strain that harbored SkATF1 showed particularly high 2-phenylethyl acetate production and the strains with introduced SkATF2 or SuATF2 revealed increased production of isobutyl acetate, isoamyl acetate, and 2-phenylethyl acetate compared to the reference strains with endogenous ATF genes. The alcohol acetyltransferase activities of the individual Atf1 and Atf2 enzymes measured in the cell extracts of the S. cerevisiae atf1 atf2 iah1 triple-null strain were detected for all the measured substrates. This indicated that S. kudriavzevii and S. uvarum Atf enzymes had broad range substrate specificity as S. cerevisiae Atf enzymes. Individual Atf1 enzymes exhibited markedly different kinetic properties since SkAtf1p showed c. twofold higher and SuAtf1p c. threefold higher Km for isoamyl alcohol than ScAtf1p. Together these results indicated that the differences found among the three Saccharomyces species during the

  8. Transgenic tobacco simultaneously overexpressing glyphosate N-acetyltransferase and 5-enolpyruvylshikimate-3-phosphate synthase are more resistant to glyphosate than those containing one gene.

    Science.gov (United States)

    Liu, Yunjun; Cao, Gaoyi; Chen, Rongrong; Zhang, Shengxue; Ren, Yuan; Lu, Wei; Wang, Jianhua; Wang, Guoying

    2015-08-01

    5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) and glyphosate N-acetyltransferase (GAT) can detoxify glyphosate by alleviating the suppression of shikimate pathway. In this study, we obtained transgenic tobacco plants overexpressing AM79 aroA, GAT, and both of them, respectively, to evaluate whether overexpression of both genes could confer transgenic plants with higher glyphosate resistance. The transgenic plants harboring GAT or AM79 aroA, respectively, showed good glyphosate resistance. As expected, the hybrid plants containing both GAT and AM79 aroA exhibited improved glyphosate resistance than the transgenic plants overexpressing only a single gene. When grown on media with high concentration of glyphosate, seedlings containing a single gene were severely inhibited, whereas plants expressing both genes were affected less. When transgenic plants grown in the greenhouse were sprayed with glyphosate, less damage was observed for the plants containing both genes. Metabolomics analysis showed that transgenic plants containing two genes could maintain the metabolism balance better than those containing one gene after glyphosate treatment. Glyphosate treatment did not lead to a huge increase of shikimate contents of tobacco leaves in transgenic plants overexpressing two genes, whereas significant increase of shikimate contents in transgenic plants containing only a single gene was observed. These results demonstrated that pyramiding both aroA and GAT in transgenic plants can enhance glyphosate resistance, and this strategy can be used for the development of transgenic glyphosate-resistant crops.

  9. Development of highly glyphosate-tolerant tobacco by coexpression of glyphosate acetyltransferase gat and EPSPS G2-aroA genes

    Institute of Scientific and Technical Information of China (English)

    Baoqing; Dun; Xujing; Wang; Wei; Lu; Ming; Chen; Wei; Zhang; Shuzhen; Ping; Zhixing; Wang; Baoming; Zhang; Min; Lin

    2014-01-01

    The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS).Glyphosate acetyltransferase(GAT)effectively detoxifies glyphosate by N-acetylation.With the aim of identifying a new strategy for development of glyphosate-tolerant crops,the plant expression vector pG2-GAT harboring gat and G2-aroA(encoding EPSPS)has been transformed into tobacco(Nicotiana tabacum)to develop novel plants with higher tolerance to glyphosate.Results from Southern and Western blotting analyses indicated that the target genes were integrated into tobacco chromosomes and expressed effectively at the protein level.Glyphosate tolerance was compared among transgenic tobacco plants containing gat,G2-aroA,or both genes.Plants containing both gat and G2-aroA genes were the most glyphosate-tolerant.This study has shown that a combination of different strategies may result in higher tolerance in transgenic crops,providing a new approach for development of glyphosate-tolerant crops.

  10. Modeling the Interaction between β-Amyloid Aggregates and Choline Acetyltransferase Activity and Its Relation with Cholinergic Dysfunction through Two-Enzyme/Two-Compartment Model

    Directory of Open Access Journals (Sweden)

    Hedia Fgaier

    2015-01-01

    Full Text Available The effect of β-amyloid aggregates on activity of choline acetyltransferase (ChAT which is responsible for synthesizing acetylcholine (ACh in human brain is investigated through the two-enzyme/two-compartment (2E2C model where the presynaptic neuron is considered as compartment 1 while both the synaptic cleft and the postsynaptic neuron are considered as compartment 2 through suggesting three different kinetic mechanisms for the inhibition effect. It is found that the incorporation of ChAT inhibition by β-amyloid aggregates into the 2E2C model is able to yield dynamic solutions for concentrations of generated β-amyloid, ACh, choline, acetate, and pH in addition to the rates of ACh synthesis and ACh hydrolysis in compartments 1 and 2. It is observed that ChAT activity needs a high concentration of β-amyloid aggregates production rate. It is found that ChAT activity is reduced significantly when neurons are exposed to high levels of β-amyloid aggregates leading to reduction in levels of ACh which is one of the most significant physiological symptoms of AD. Furthermore, the system of ACh neurocycle is dominated by the oscillatory behavior when ChAT enzyme is completely inhibited by β-amyloid. It is observed that the direct inactivation of ChAT by β-amyloid aggregates may be a probable mechanism contributing to the development of AD.

  11. The histone acetyltransferase domains of CREB-binding protein (CBP) and p300/CBP-associated factor are not necessary for cooperativity with the class II transactivator.

    Science.gov (United States)

    Harton, J A; Zika, E; Ting, J P

    2001-10-19

    The class II transactivator (CIITA) is a transcriptional co-activator regulating the constitutive and interferon-gamma-inducible expression of class II major histocompatibility complex (MHC) and related genes. Promoter remodeling occurs following CIITA induction, suggesting the involvement of chromatin remodeling factors. Transcription of numerous genes requires the histone acetyltransferase (HAT) activities of CREB-binding protein (CBP), p300, and/or p300/CBP-associated factor (pCAF). These co-activators cooperate with CIITA and are hypothesized to promote class II major histocompatibility complex transcription through their HAT activity. To directly test this, we used HAT-defective CBP and pCAF. We demonstrate that cooperation between CIITA and CBP is independent of CBP HAT activity. Further, although pCAF enhances CIITA-mediated transcription, pCAF HAT domain dependence appears contingent upon the concentration of available CIITA. When HAT-defective CBP and pCAF are both present, cooperativity with CIITA is maintained. Consistent with a recent report, we show that nuclear localization of CIITA is enhanced by lysine 144, an in vitro target of pCAF-mediated HAT. Yet we find that neither mutation of lysine 144 nor deletion of residues 132-209 affects transcriptional cooperation with CBP or pCAF. Thus, acetylation of this residue may not be the primary mechanism for pCAF/CBP cooperation with CIITA. In conclusion, the HAT activities of the co-activators are not necessary for cooperation with CIITA.

  12. Small molecule inhibition of arylamine N-acetyltransferase Type I inhibits proliferation and invasiveness of MDA-MB-231 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tiang, Jacky M. [School of Biomedical Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia); Butcher, Neville J., E-mail: n.butcher@uq.edu.au [School of Biomedical Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia); Minchin, Rodney F. [School of Biomedical Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia)

    2010-02-26

    Arylamine N-acetyltransferase 1 is a phase II metabolizing enzyme that has been associated with certain breast cancer subtypes. While it has been linked to breast cancer risk because of its role in the metabolic activation and detoxification of carcinogens, recent studies have suggested it may be important in cell growth and survival. To address the possible importance of NAT1 in breast cancer, we have used a novel small molecule inhibitor (Rhod-o-hp) of the enzyme to examine growth and invasion of the breast adenocarcinoma line MDA-MB-231. The inhibitor significantly reduced cell growth by increasing the percent of cells in G2/M phase of the cell cycle. Rhod-o-hp also reduced the ability of the MDA-MB-231 cells to grow in soft agar. Using an in vitro invasion assay, the inhibitor significantly reduced the invasiveness of the cells. To test whether this effect was due to inhibition of NAT1, the enzyme was knocked down using a lentivirus-based shRNA approach and invasion potential was significantly reduced. Taken together, the results of this study demonstrate that NAT1 activity may be important in breast cancer growth and metastasis. The study suggests that NAT1 is a novel target for breast cancer treatment.

  13. Reduced expression of choline acetyltransferase in vagal motoneurons and gastric motor dysfunction in a 6-OHDA rat model of Parkinson's disease.

    Science.gov (United States)

    Zheng, Li-Fei; Wang, Zhi-Yong; Li, Xiao-feng; Song, Jin; Hong, Feng; Lian, Hui; Wang, Qian; Feng, Xiao-Yan; Tang, Yuan-yuan; Zhang, Yue; Zhu, Jin-Xia

    2011-10-28

    Parkinson's disease (PD) has been characterized by dopaminergic neuron degeneration in the substantia nigra (SN) accompanied by pathology of the dorsal motor nucleus of the vagus (DMV). PD patients have often experienced gastrointestinal dysfunctions, such as gastroparesis. However, the mechanism underlying these symptoms in PD patients is not clear. In the present study, we investigated alterations of cholinergic and catecholaminergic neurons in the DMV and gastric motor function in rats microinjected with 6-hydroxydopamine (6-OHDA) bilaterally into the SN (referred to as 6-OHDA rats) and explored possible mechanisms. A strain gauge force transducer was used to record gastric motility in vivo. Expression of choline acetyltransferase (ChAT) and tyrosine hydroxylase (TH) was evaluated by immunofluorescence and western blot analysis. Acetylcholine (Ach) content was measured using ultra-performance liquid chromatography tandem mass spectrometry (UPLC/MS/MS) analysis. After treatment with 6-OHDA for 6weeks, 6-OHDA rats exhibited decreased ChAT and enhanced TH expression in the DMV and decreased Ach content in the gastric muscular layer. Delayed gastric emptying and impaired gastric motility in vivo were observed in 6-OHDA rats. The results of the present study indicated that decreased ChAT and enhanced TH expression in the DMV may be correlated with the development of delayed gastric emptying and impaired gastric motility, which may be partly due to the decreased Ach release from the vagus. PMID:21955729

  14. Isolation of Two Unknown Genes Potentially Involved in Differentiation of the Hematopoietic Pathway, and Studies of Spermidine/Spermine Acetyltransferase Regulation

    Energy Technology Data Exchange (ETDEWEB)

    Kubera, C.; Gavin, I.; Huberman, E.

    2002-01-01

    Differential display identified a number of candidate genes involved with growth and differentiation in the human leukemia cell lines HL-60 and HL-525. Two of these genes were previously unknown, and one is the gene for the enzyme spermidine/spermine acetyltransferase (SSAT). One of our objectives is to isolate and sequence the unknown genes, 631A1 and 510C1, in order to characterize them and determine their functions. The other is to determine how SSAT is regulated, and look at how the polyamines that SSAT regulates effect macrophage differentiation. By screening the CEM T-cell DNA library and the fetal brain library, we were able to identify clones that had inserts with homology to the 631A1 cDNA probe sequence. The insert was amplified using the polymerase chain reaction (PCR) and is currently being sent to the University of Chicago for automated sequencing. The library screens for 510C1 are currently underway, but hybridization of the 510C1 cDNA probe with nylon membranes containing CEM library phage DNA produced strong signal, indicating the gene is there. SSAT experiments identified that the rate-limiting enzyme that marks the polyamines spermidine and spermine for degradation is regulated by PKC and a transcription factor called Nrf2. The knowledge of regulation and function of these genes involved in macrophage differentiation will provide new insight into this cellular process, potentially making it possible to discover the roots of the problems that cause cancerous diseases.

  15. Transcription Factors Ets2 and Sp1 Act Synergistically with Histone Acetyltransferase p300 in Activating Human Interleukin-12 p40 Promoter

    Institute of Scientific and Technical Information of China (English)

    Hai-Jing SUN; Xin XU; Xiu-Li WANG; Liang WEI; Fen LI; Jun LU; Bai-Qu HUANG

    2006-01-01

    There has been considerable interest in researching the regulatory mechanisms that control the synthesis of interleukin (IL)-12, which plays a central role in the differentiation of T-helper-1 cells. In this study, we performed a series of transient transfection experiments designed to elucidate the functional relationship between the IL-12 promoter-specific transcription factors (Ets2 and Spl) and histone acetylation modification in IL-12 regulation mediated by p300 and various histone deacetylases (HDACs). Results presented in this report demonstrated that the transcription factors Ets2 and Spl acted synergistically with p300to activate the human IL-12 promoter. The histone acetyltransferase (HAT) activity of p300 was required for this synergic effect, because the adenovirus E1A protein inhibited the synergy. Conversely, HDACs repressed the synergic effect of transcription factors and histone acetylation on the activation of IL-12, while p300 was able to rectify it. These data indicated that Ets2 and Sp1 worked concertedly and synergistically with p300 in the regulation of human IL-12 expression.

  16. The Histone Acetyltransferase Gcn5 Regulates ncRNA-ICR1 and FLO11 Expression during Pseudohyphal Development in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Long-Chi Wang

    2015-01-01

    Full Text Available Filamentous growth is one of the key features of pathogenic fungi during the early infectious phase. The pseudohyphal development of yeast Saccharomyces cerevisiae shares similar characteristics with hyphae elongation in pathogenic fungi. The expression of FLO11 is essential for adhesive growth and filament formation in yeast and is governed by a multilayered transcriptional network. Here we discovered a role for the histone acetyltransferase general control nonderepressible 5 (Gcn5 in regulating FLO11-mediated pseudohyphal growth. The expression patterns of FLO11 were distinct in haploid and diploid yeast under amino acid starvation induced by 3-amino-1,2,4-triazole (3AT. In diploids, FLO11 expression was substantially induced at a very early stage of pseudohyphal development and decreased quickly, but in haploids, it was gradually induced. Furthermore, the transcription factor Gcn4 was recruited to the Sfl1-Flo8 toggle sites at the FLO11 promoter under 3AT treatment. Moreover, the histone acetylase activity of Gcn5 was required for FLO11 induction. Finally, Gcn5 functioned as a negative regulator of the noncoding RNA ICR1, which is known to suppress FLO11 expression. Gcn5 plays an important role in the regulatory network of FLO11 expression via Gcn4 by downregulating ICR1 expression, which derepresses FLO11 for promoting pseudohyphal development.

  17. Tetrandrine has anti-adipogenic effect on 3T3-L1 preadipocytes through the reduced expression and/or phosphorylation levels of C/EBP-α, PPAR-γ, FAS, perilipin A, and STAT-3.

    Science.gov (United States)

    Jang, Byeong-Churl

    2016-08-01

    Tetrandrine is a bisbenzylisoquinoline alkaloid isolated from the roots of Stephania tetrandra S. Moore and has been shown to possess anti-inflammatory and anti-cancerous activities. In this study, the effect of tetrandrine on adipogenesis in 3T3-L1 preadipocytes was investigated. Tetrandrine at 10 μM concentration strongly inhibited lipid accumulation and triglyceride (TG) synthesis during the differentiation of 3T3-L1 preadipocytes into adipocytes. On mechanistic levels, tetrandrine reduced not only the expressions of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), fatty acid synthase (FAS), and perilipin A but also the phosphorylation levels of signal transducer and activator of transcription-3 (STAT-3) during 3T3-L1 adipocyte differentiation. Tetrandrine also reduced the mRNA expression of leptin, but not adiponectin, during 3T3-L1 adipocyte differentiation. Collectively, these findings show that tetrandrine has strong anti-adipogenic effect on 3T3-L1 preadipocytes and the effect is largely attributable to the reduced expression and/or phosphorylation levels of C/EBP-α, PPAR-γ, FAS, perilipin A, and STAT-3. PMID:27246736

  18. Buckwheat (Fagopyrum esculentum M. Sprout Treated with Methyl Jasmonate (MeJA Improved Anti-Adipogenic Activity Associated with the Oxidative Stress System in 3T3-L1 Adipocytes

    Directory of Open Access Journals (Sweden)

    Jeong-Ho Lim

    2013-01-01

    Full Text Available Buckwheat sprouts contain various bioactive compounds including rutin which have a number of biological activities. We have previously shown that buckwheat sprouts (TBWE treated with methyl jasmonate (MeJA significantly increased the amount of phenolics and the antioxidant activity. The aim of this study was to demonstrate the effect of TBWE on anti-adipogenesis and pro-oxidant enzyme in 3T3-L1 adipocytes. We also evaluated the anti-oxidative activity of TBWE in adipocytes by using the nitroblue tetrazolium assay. Our data showed that TBWE markedly inhibited adipocyte differentiation and ROS production in 3T3-L1 cells compared with control groups. Moreover, TBWE has strongly shown the inhibition of adipogenic transcription factor as well as pro-oxidant enzymes. Together, we demonstrate that the MeJA treatment significantly increased the amount of phenolic compound, resulting in the suppression of adipogenesis and ROS production in the 3T3-L1 cells. These findings indicate that TBWE has the potential for anti-adipogenesis activity with anti-oxidative properties.

  19. Buckwheat (Fagopyrum esculentum M.) sprout treated with methyl jasmonate (MeJA) improved anti-adipogenic activity associated with the oxidative stress system in 3T3-L1 adipocytes.

    Science.gov (United States)

    Lee, Young-Jun; Kim, Kui-Jin; Park, Kee-Jai; Yoon, Bo-Ra; Lim, Jeong-Ho; Lee, Ok-Hwan

    2013-01-11

    Buckwheat sprouts contain various bioactive compounds including rutin which have a number of biological activities. We have previously shown that buckwheat sprouts (TBWE) treated with methyl jasmonate (MeJA) significantly increased the amount of phenolics and the antioxidant activity. The aim of this study was to demonstrate the effect of TBWE on anti-adipogenesis and pro-oxidant enzyme in 3T3-L1 adipocytes. We also evaluated the anti-oxidative activity of TBWE in adipocytes by using the nitroblue tetrazolium assay. Our data showed that TBWE markedly inhibited adipocyte differentiation and ROS production in 3T3-L1 cells compared with control groups. Moreover, TBWE has strongly shown the inhibition of adipogenic transcription factor as well as pro-oxidant enzymes. Together, we demonstrate that the MeJA treatment significantly increased the amount of phenolic compound, resulting in the suppression of adipogenesis and ROS production in the 3T3-L1 cells. These findings indicate that TBWE has the potential for anti-adipogenesis activity with anti-oxidative properties.

  20. Molecular Structure of WlbB, a Bacterial N-Acetyltransferase Involved in the Biosynthesis of 2,3-Diacetamido-2,3-dideoxy-d-mannuronic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Thoden, James B.; Holden, Hazel M. (UW)

    2010-09-08

    The pathogenic bacteria Pseudomonas aeruginosa and Bordetella pertussis contain in their outer membranes the rare sugar 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid. Five enzymes are required for the biosynthesis of this sugar starting from UDP-N-acetylglucosamine. One of these, referred to as WlbB, is an N-acetyltransferase that converts UDP-2-acetamido-3-amino-2,3-dideoxy-D-glucuronic acid (UDP-GlcNAc3NA) to UDP-2,3-diacetamido-2,3-dideoxy-D-glucuronic acid (UDP-GlcNAc3NAcA). Here we report the three-dimensional structure of WlbB from Bordetella petrii. For this analysis, two ternary structures were determined to 1.43 {angstrom} resolution: one in which the protein was complexed with acetyl-CoA and UDP and the second in which the protein contained bound CoA and UDP-GlcNAc3NA. WlbB adopts a trimeric quaternary structure and belongs to the L{beta}H superfamily of N-acyltransferases. Each subunit contains 27 {beta}-strands, 23 of which form the canonical left-handed {beta}-helix. There are only two hydrogen bonds that occur between the protein and the GlcNAc3NA moiety, one between O{sup {delta}1} of Asn 84 and the sugar C-3{prime} amino group and the second between the backbone amide group of Arg 94 and the sugar C-5{prime} carboxylate. The sugar C-3{prime} amino group is ideally positioned in the active site to attack the si face of acetyl-CoA. Given that there are no protein side chains that can function as general bases within the GlcNAc3NA binding pocket, a reaction mechanism is proposed for WlbB whereby the sulfur of CoA ultimately functions as the proton acceptor required for catalysis.

  1. A human parvovirus, adeno-associated virus, as a eucaryotic vector: Transient expression and encapsidation of the procaryotic gene for chloramphenicol acetyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Tratschin, J.D.; West, M.H.P.; Sandbank, T.; Carter, B.J.

    1984-10-01

    The authors have used the defective human parvovirus adeno-associated virus (AAV) as a novel eurocaryotic vector (parvector) for the expression of a foreign gene in human cells. The recombinant, pAV2, contains the AAV genome in a pBR322-derived bacterial plasmid. When pAV2 is transfected into human cells together with helper adenovirus particles, the AAV genome is rescued from the recombinant plasmid and replicated to produce infectious AAV particles at high efficiency. To create a vector, we inserted a procaryotic sequence coding for chloramphenicol acetyltransferase (CAT) into derivatives of pAV2 following either of the AAV promoters p/sub 40/ (pAVHiCAT) and p/sub 19/ (pAVBcCAT). When transfected into human 293 cells or HeLa cells, pAVHiCAT expressed CAT activity in the absence of adenovirus. In the presence of adenovirus, this vector produced increased amounts of CAT activity and the recombinant AAV-CAT genome was replicated. In 293 cells, pAVBcCAT expressed a similar amount of CAT activity in the absence or presence of adenovirus and the recombinant AAV-CAT genome was not replicated. In HeLa cells, pAVBcCAT expressed low levels of CAT activity, but this level was elevated by coinfection with adenovirus particles or by cotransfection with a plasmid which expressed the adenovirus early region 1A (E1A) product. The E1A product is a transcriptional activator and is expressed in 293 cells. Thus, expression from two AAV promoters is differentially regulated: expression from p/sub 19/ is increased by E1A, whereas p/sub 40/ yields high levels of constitutive expression in the absence of E1A. Both AAV vectors were packaged into AAV particles by complementation with wild-type AAV and yielded CAT activity when subsequently infected into cells in the presence of adenovirus.

  2. Non-syndromic retinitis pigmentosa due to mutations in the mucopolysaccharidosis type IIIC gene, heparan-alpha-glucosaminide N-acetyltransferase (HGSNAT)

    Science.gov (United States)

    Haer-Wigman, Lonneke; Newman, Hadas; Leibu, Rina; Bax, Nathalie M.; Baris, Hagit N; Rizel, Leah; Banin, Eyal; Massarweh, Amir; Roosing, Susanne; Lefeber, Dirk J.; Zonneveld-Vrieling, Marijke N.; Isakov, Ofer; Shomron, Noam; Sharon, Dror; Den Hollander, Anneke I.; Hoyng, Carel B.; Cremers, Frans P.M.; Ben-Yosef, Tamar

    2015-01-01

    Retinitis pigmentosa (RP), the most common form of inherited retinal degeneration, is clinically and genetically heterogeneous and can appear as syndromic or non-syndromic. Mucopolysaccharidosis type IIIC (MPS IIIC) is a lethal disorder, caused by mutations in the heparan-alpha-glucosaminide N-acetyltransferase (HGSNAT) gene and characterized by progressive neurological deterioration, with retinal degeneration as a prominent feature. We identified HGSNAT mutations in six patients with non-syndromic RP. Whole exome sequencing (WES) in an Ashkenazi Jewish Israeli RP patient revealed a novel homozygous HGSNAT variant, c.370A>T, which leads to partial skipping of exon 3. Screening of 66 Ashkenazi RP index cases revealed an additional family with two siblings homozygous for c.370A>T. WES in three Dutch siblings with RP revealed a complex HGSNAT variant, c.[398G>C; 1843G>A] on one allele, and c.1843G>A on the other allele. HGSNAT activity levels in blood leukocytes of patients were reduced compared with healthy controls, but usually higher than those in MPS IIIC patients. All patients were diagnosed with non-syndromic RP and did not exhibit neurological deterioration, or any phenotypic features consistent with MPS IIIC. Furthermore, four of the patients were over 60 years old, exceeding by far the life expectancy of MPS IIIC patients. HGSNAT is highly expressed in the mouse retina, and we hypothesize that the retina requires higher HGSNAT activity to maintain proper function, compared with other tissues associated with MPS IIIC, such as the brain. This report broadens the spectrum of phenotypes associated with HGSNAT mutations and highlights the critical function of HGSNAT in the human retina. PMID:25859010

  3. N-Acetyltransferase 2 and glutathione s-transferase M1 in colon and rectal cancer cases from an industrialized area.

    Science.gov (United States)

    Golka, Klaus; Roemer, Hermann C; Weistenhöfer, Wobbeke; Blaszkewicz, Meinolf; Hammad, Seddik; Reckwitz, Thomas; Loehlein, Dietrich; Hartel, Mark; Hengstler, Jan G; Geller, Frank

    2012-01-01

    Apart from genetics, nutrition, and environment, occupational factors also play an important role in colon and rectal cancer development. The aim of this study was to examine these cancer types in an area of former coal, iron, and steel industries, which was found to display an increased incidence of colon cancer mortality. N-Acetyltransferase 2 (NAT2) and glutathione S-transferase M1 (GSTM1) genotypes were investigated in 108 colon cancer cases, 80 rectum cancer cases, and 188 controls (suffering from nonmalignant diseases). Further, in a pilot study, 28 colorectal cancer patients were NAT2 phenotyped by the caffeine test. Possible occupational and nonoccupational risk factors were investigated by a personal interview. The frequency of rapid NAT2 genotype was 35% in colon cancer cases, 47% in rectal cancer cases, and 42% in controls (GSTM1 0/0 genotype: 53, 46, and 47%, respectively). In the 29 patients with cancer in the ascending colon, 10% were of the rapid NAT2 genotype. In the pilot study the frequency of the rapid NAT2 phenotype was 49%. The only major professional group with an elevated risk was painters (colon cancer OR 2.48, 95% CI 0.4-15.23; rectal cancer OR 5.65, 95% CI 1.06-30.21). In contrast to early studies, in the present study the slow NAT2 status is overrepresented. As colorectal cancer is associated with nutrition and physical activity, present findings may be due to excessive physical heavy work and the resulting nutrition in this area.

  4. Refinement of the prediction of N-acetyltransferase 2 (NAT2) phenotypes with respect to enzyme activity and urinary bladder cancer risk.

    Science.gov (United States)

    Selinski, Silvia; Blaszkewicz, Meinolf; Ickstadt, Katja; Hengstler, Jan G; Golka, Klaus

    2013-12-01

    Polymorphisms of N-acetyltransferase 2 (NAT2) are well known to modify urinary bladder cancer risk as well as efficacy and toxicity of pharmaceuticals via reduction in the enzyme's acetylation capacity. Nevertheless, the discussion about optimal NAT2 phenotype prediction, particularly differentiation between different degrees of slow acetylation, is still controversial. Therefore, we investigated the impact of single nucleotide polymorphisms and their haplotypes on slow acetylation in vivo and on bladder cancer risk. For this purpose, we used a study cohort of 1,712 bladder cancer cases and 2,020 controls genotyped for NAT2 by RFLP-PCR and for the tagSNP rs1495741 by TaqMan(®) assay. A subgroup of 344 individuals was phenotyped by the caffeine test in vivo. We identified an 'ultra-slow' acetylator phenotype based on combined *6A/*6A, *6A/*7B and *7B/*7B genotypes containing the homozygous minor alleles of C282T (rs1041983, *6A, *7B) and G590A (rs1799930, *6A). 'Ultra-slow' acetylators have significantly about 32 and 46 % lower activities of caffeine metabolism compared with other slow acetylators and with the *5B/*5B genotypes, respectively (P < 0.01, both). The 'ultra-slow' genotype showed an association with bladder cancer risk in the univariate analysis (OR = 1.31, P = 0.012) and a trend adjusted for age, gender and smoking habits (OR = 1.22, P = 0.082). In contrast, slow acetylators in general were not associated with bladder cancer risk, neither in the univariate (OR = 1.02, P = 0.78) nor in the adjusted (OR = 0.98, P = 0.77) analysis. In conclusion, this study suggests that NAT2 phenotype prediction should be refined by consideration of an 'ultra-slow' acetylation genotype.

  5. Polymorphism of N-acetyltransferase 2 (NAT2) Gene Polymorphism in Shanghai population:Occupational and Non-occupational Bladder Cancer Patient Groups

    Institute of Scientific and Technical Information of China (English)

    QING-WEN MA; GUO-FANG LIN; JI-GANG CHEN; CUI-QING XIANG; WEI-CHAO GUO; KLAUS GOLKA; JIAN-HUA SHEN

    2004-01-01

    Arylamine N-acetyltransferases (NATs) are involved in the detoxification of aromatic amines and hydrazine. In order to explore the possible association of NAT2 polymorphism with bladder cancer risk in benzidine exposed or non-exposed Chinese individuals, healthy subjects, subjects with bladder cancer of a former benzidine exposed cohort in Shanghai dyestuff industry and a group of bladder cancer patients without known occupational exposure to aromatic amines were genotyped for NAT2 gene polymorphism. Methods NAT2 genotyping was performed with a set of RFLP procedures at seven major polymorphic loci of gene coding area: G191A, C282T, T341C, C481T, G590A, A803G and G857A. Results The wild allele NAT2 *4 was the most prevalent allele (59%) in healthy individuals. The alleles NAT2*6A and NAT2*7B were also frequently observed (21% and 17%, respectively). In contrast to Caucasians, the percentage of slow acetylators was lower (12% in Chinese vs. 58% in Caucasians, P<0.001). No relevant differences were observed for homogenous rapid, heterogeneous rapid/slow and homogeneous slow acetylation genotypes between the healthy subjects and both groups of bladder cancer patients. Conclusion The present work did not support the association of slow acetylating genotypes of NAT2 gene with elevated risk of bladder cancer in Chinese whereas it was documented as an important genetically determined risk factor in Caucasians. Different mechanisms might play a role in individual susceptibility to bladder cancer related with aromatic amine exposure in various races or ethnic groups.

  6. Three-dimensional collagen I promotes gemcitabine resistance in vitro in pancreatic cancer cells through HMGA2-dependent histone acetyltransferase expression.

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    Surabhi Dangi-Garimella

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is associated with a pronounced collagen-rich stromal reaction that has been shown to contribute to chemo-resistance. We have previously shown that PDAC cells are resistant to gemcitabine chemotherapy in the collagen microenvironment because of increased expression of the chromatin remodeling protein high mobility group A2 (HMGA2. We have now found that human PDAC tumors display higher levels of histone H3K9 and H3K27 acetylation in fibrotic regions. We show that relative to cells grown on tissue culture plastic, PDAC cells grown in three-dimensional collagen gels demonstrate increased histone H3K9 and H3K27 acetylation, along with increased expression of p300, PCAF and GCN5 histone acetyltransferases (HATs. Knocking down HMGA2 attenuates the effect of collagen on histone H3K9 and H3K27 acetylation and on collagen-induced p300, PCAF and GCN5 expression. We also show that human PDAC tumors with HMGA2 demonstrate increased histone H3K9 and H3K27 acetylation. Additionally, we show that cells in three-dimensional collagen gels demonstrate increased protection against gemcitabine. Significantly, down-regulation of HMGA2 or p300, PCAF and GCN5 HATs sensitizes the cells to gemcitabine in three-dimensional collagen. Overall, our results increase our understanding of how the collagen microenvironment contributes to chemo-resistance in vitro and identify HATs as potential therapeutic targets against this deadly cancer.

  7. No germline mutations in the histone acetyltransferase gene EP300 in BRCA1 and BRCA2 negative families with breast cancer and gastric, pancreatic, or colorectal cancer

    International Nuclear Information System (INIS)

    Mutations in BRCA1, BRCA2, ATM, TP53, CHK2 and PTEN account for many, but not all, multiple-case breast and ovarian cancer families. The histone acetyltransferase gene EP300 may function as a tumour suppressor gene because it is sometimes somatically mutated in breast, colorectal, gastric and pancreatic cancers, and is located on a region of chromosome 22 that frequently undergoes loss of heterozygosity in many cancer types. We hypothesized that germline mutations in EP300 may account for some breast cancer families that include cases of gastric, pancreatic and/or colorectal cancer. We screened the entire coding region of EP300 for mutations in the youngest affected members of 23 non-BRCA1/BRCA2 breast cancer families with at least one confirmed case of gastric, pancreatic and/or colorectal cancer. These families were ascertained in Australia through the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer. Denaturing HPLC analysis identified a heterozygous alteration at codon 211, specifically a GGC to AGC (glycine to serine) alteration, in two individuals. This conservative amino acid change was not within any known functional domains of EP300. The frequency of the Ser211 variant did not differ significanlty between a series of 352 breast cancer patients (4.0%) and 254 control individuals (2.8%; P = 0.5). The present study does not support a major role for EP300 mutations in breast and ovarian cancer families with a history of gastric, pancreatic and/or colorectal cancer

  8. leptin-induced growth stimulation of breast cancer cells involves recruitment of histone acetyltransferases and mediator complex to CYCLIN D1 promoter via activation of Stat3.

    Science.gov (United States)

    Saxena, Neeraj K; Vertino, Paula M; Anania, Frank A; Sharma, Dipali

    2007-05-01

    Numerous epidemiological studies documented that obesity is a risk factor for breast cancer development in postmenopausal women. Leptin, the key player in the regulation of energy balance and body weight control also acts as a growth factor on certain organs in both normal and disease state. In this study, we analyzed the role of leptin and the molecular mechanism(s) underlying its action in breast cancer cells that express both short and long isoforms of leptin receptor. Leptin increased MCF7 cell population in the S-phase of the cell cycle along with a robust increase in CYCLIN D1 expression. Also, leptin induced Stat3-phosphorylation-dependent proliferation of MCF7 cells as blocking Stat3 phosphorylation with a specific inhibitor, AG490, abolished leptin-induced proliferation. Using deletion constructs of CYCLIN D1 promoter and chromatin immunoprecipitation assay, we show that leptin induced increase in CYCLIN D1 promoter activity is mediated through binding of activated Stat3 at the Stat binding sites and changes in histone acetylation and methylation. We also show specific involvement of coactivator molecules, histone acetyltransferase SRC1, and mediator complex in leptin-mediated regulation of CYCLIN D1 promoter. Importantly, silencing of SRC1 and Med1 abolished the leptin induced increase in CYCLIN D1 expression and MCF7 cell proliferation. Intriguingly, recruitment of both SRC1 and Med1 was dependent on phosphorylated Stat3 as AG490 treatment inhibited leptin-induced recruitment of these coactivators to CYCLIN D1 promoter. Our data suggest that CYCLIN D1 may be a target gene for leptin mediated growth stimulation of breast cancer cells and molecular mechanisms involve activated Stat3-mediated recruitment of distinct coactivator complexes.

  9. Immunoreactivity for Choline Acetyltransferase of Peripheral-Type (pChAT) in the Trigeminal Ganglion Neurons of the Non-Human Primate Macaca fascicularis

    International Nuclear Information System (INIS)

    Transcripts of the choline acetyltransferase (ChAT) gene reveal a number of different splice variants including ChAT of a peripheral type (pChAT). Immunohistochemical staining of the brain using an antibody against pChAT clearly revealed peripheral cholinergic neurons, but failed to detect cholinergic neurons in the central nervous system. In rodents, pChAT-immunoreactivity has been detected in cholinergic parasympathetic postganglionic and enteric ganglion neurons. In addition, pChAT has been observed in non-cholinergic neurons such as peripheral sensory neurons in the trigeminal and dorsal root ganglia. The common type of ChAT (cChAT) has been investigated in many parts of the brain and the spinal cord of non-human primates, but little information is available about the localization of pChAT in primate species. Here, we report the detection of pChAT immunoreactivity in trigeminal ganglion (TG) neurons and its co-localization with Substance P (SP) and/or calcitonin gene-related peptide (CGRP) in the cynomolgus monkey, Macaca fascicularis. Neurons positive for pChAT were observed in a rather uniform pattern in approximately half of the trigeminal neurons throughout the TG. Most pChAT-positive neurons had small or medium-sized cell bodies. Double-immunofluorescence staining showed that 85.1% of SP-positive cells and 74.0% of CGRP-positive cells exhibited pChAT immunoreactivity. Most pChAT-positive cells were part of a larger population of neurons that co-expressed SP and/or CGRP

  10. Nucleotide sequence and genetic analysis of the Azotobacter chroococcum nifUSVWZM gene cluster, including a new gene (nifP) which encodes a serine acetyltransferase.

    Science.gov (United States)

    Evans, D J; Jones, R; Woodley, P R; Wilborn, J R; Robson, R L

    1991-09-01

    Nucleotide sequence was obtained for a region of 7,099 bp spanning the nifU, nifS, nifV, nifW, nifZ, and nifM genes from Azotobacter chroococcum. Chromosomal mutations constructed at several sites within the locus confirmed a requirement for this region for expression of the molybdenum nitrogenase in this organism. The genes are tightly clustered and ordered as in Klebsiella pneumoniae except for two additional open reading frames (ORFs) between nifV and nifW. The arrangement of genes in A. chroococcum closely matches that described for Azotobacter vinelandii. The polypeptide encoded by ORF4 immediately downstream from nifV is 41% identical over 186 amino acids to the product of the cysE gene from Escherichia coli, which encodes serine acetyltransferase (SAT), a key enzyme in cysteine biosynthesis. Plasmids which potentially express ORF4 complemented E. coli JM39, a cysteine auxotroph which lacks SAT. SAT activity was detected in crude extracts of one such complemented strain. A strain of A. chroococcum carrying a chromosomal disruption of ORF4 grew normally with ammonium as the N source but more slowly than the parental strain when N2 was the sole N source. These data suggest that ORF4 encodes a nif-specific SAT required for optimizing expression of nitrogenase activity. ORF4 was assigned the name nifP. nifP may be required to boost rates of synthesis or intracellular concentrations of cysteine or methionine. Sequence identity between nifV and leuA gene products suggests that nifV may catalyze a condensation reaction analogous to that carried out by isopropylmalate synthase (LEUA) but in which acetyl coenzyme and alpha-ketoglutarate are substrates for the formation of homocitrate, the proposed product of NIFV activity. PMID:1885524

  11. Differential co-localization with choline acetyltransferase in nervus terminalis suggests functional differences for GnRH isoforms in bonnethead sharks (Sphyrna tiburo).

    Science.gov (United States)

    Moeller, John F; Meredith, Michael

    2010-12-17

    The nervus terminalis (NT) is a vertebrate cranial nerve whose function in adults is unknown. In bonnethead sharks, the nerve is anatomically independent of the olfactory system, with two major cell populations within one or more ganglia along its exposed length. Most cells are immunoreactive for either gonadotropin-releasing hormone (GnRH) or RF-amide-like peptides. To define further the cell populations and connectivity, we used double-label immunocytochemistry with antisera to different isoforms of GnRH and to choline acetyltransferase (ChAT). The labeling patterns of two GnRH antisera revealed different populations of GnRH-immunoreactive (ir) cell profiles in the NT ganglion. One antiserum labeled a large group of cells and fibers, which likely contain mammalian GnRH (GnRH-I) as described in previous studies and which were ChAT immunoreactive. The other antiserum labeled large club-like structures, which were anuclear, and a sparse number of fibers, but with no clear labeling of cell bodies in the ganglion. These club structures were choline acetyltrasferase (ChAT)-negative, and preabsorption control tests suggest they may contain chicken-GnRH-II (GnRH-II) or dogfish GnRH. The second major NT ganglion cell-type was immunoreactive for RF-amides, which regulate GnRH release in other vertebrates, and may provide an intraganglionic influence on GnRH release. The immunocytochemical and anatomical differences between the two GnRH-immunoreactive profile types indicate possible functional differences for these isoforms in the NT. The club-like structures may be sites of GnRH release into the general circulation since these structures were observed near blood vessels and resembled structures seen in the median eminence of rats. PMID:20950589

  12. Histone acetyltransferase (HAT) activity of p300 modulates human T lymphotropic virus type 1 p30II-mediated repression of LTR transcriptional activity

    International Nuclear Information System (INIS)

    Human T-lymphotropic virus type-1 (HTLV-1) is a deltaretrovirus that causes adult T cell leukemia/lymphoma, and is implicated in a variety of lymphocyte-mediated inflammatory disorders. HTLV-1 provirus has regulatory and accessory genes in four pX open reading frames. HTLV-1 pX ORF-II encodes two proteins, p13II and p30II, which are incompletely defined in virus replication or pathogenesis. We have demonstrated that pX ORF-II mutations block virus replication in vivo and that ORF-II encoded p30II, a nuclear-localizing protein that binds with CREB-binding protein (CBP)/p300, represses CREB and Tax responsive element (TRE)-mediated transcription. Herein, we have identified p30II motifs important for p300 binding and in regulating TRE-mediated transcription in the absence and presence of HTLV-1 provirus. Within amino acids 100-179 of p30II, a region important for repression of LTR-mediated transcription, we identified a single lysine residue at amino acid 106 (K3) that significantly modulates the ability of p30II to repress TRE-mediated transcription. Exogenous p300, in a dose-responsive manner, reverses p30II-dependent repression of TRE-mediated transcription, in the absence or presence of the provirus, In contrast to wild type p300, p300 HAT mutants (defective in histone acetyltransferase activity) only partially rescued p30II-mediated LTR repression. Deacetylation by histone deacetylase-1 (HDAC-1) enhanced p30II-mediated LTR repression, while inhibition of deacetylation by trichostatin A decreases p30II-mediated LTR repression. Collectively, our data indicate that HTLV-1 p30II modulates viral gene expression in a cooperative manner with p300-mediated acetylation

  13. Dual N- and C-terminal helices are required for endoplasmic reticulum and lipid droplet association of alcohol acetyltransferases in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Jyun-Liang Lin

    Full Text Available In the yeast Saccharomyces cerevisiae two alcohol acetyltransferases (AATases, Atf1 and Atf2, condense short chain alcohols with acetyl-CoA to produce volatile acetate esters. Such esters are, in large part, responsible for the distinctive flavors and aromas of fermented beverages including beer, wine, and sake. Atf1 and Atf2 localize to the endoplasmic reticulum (ER and Atf1 is known to localize to lipid droplets (LDs. The mechanism and function of these localizations are unknown. Here, we investigate potential mechanisms of Atf1 and Atf2 membrane association. Segments of the N- and C-terminal domains of Atf1 (residues 24-41 and 508-525, respectively are predicted to be amphipathic helices. Truncations of these helices revealed that the terminal domains are essential for ER and LD association. Moreover, mutations of the basic or hydrophobic residues in the N-terminal helix and hydrophobic residues in the C-terminal helix disrupted ER association and subsequent sorting from the ER to LDs. Similar amphipathic helices are found at both ends of Atf2, enabling ER and LD association. As was the case with Atf1, mutations to the N- and C-terminal helices of Atf2 prevented membrane association. Sequence comparison of the AATases from Saccharomyces, non-Saccharomyces yeast (K. lactis and P. anomala and fruits species (C. melo and S. lycopersicum showed that only AATases from Saccharomyces evolved terminal amphipathic helices. Heterologous expression of these orthologs in S. cerevisiae revealed that the absence of terminal amphipathic helices eliminates LD association. Combined, the results of this study suggest a common mechanism of membrane association for AATases via dual N- and C-terminal amphipathic helices.

  14. Specific expression of myogenic,adipogenic and osteogenic gene in skeletal muscle of mdx mice%mdx小鼠骨骼肌组织成肌、成脂、成骨基因的特异性表达

    Institute of Scientific and Technical Information of China (English)

    冷雁; 张为西; 周琛; 郑振扬; 张成; 李秋玲

    2011-01-01

    BACKGROUND: Duchenne's muscular dystrophy (DMD) is a fatal recessive X-Iinked form of muscular dystrophy characterized by prog ressive muscular degeneration, and there is no cure for DMD currently. Stem cell transplantation may provide us with a creative perspective. But the myogenic differentiation rate of transplanted cells is quite low in skeletal muscle. OBJECTIVE: The differences of myogenic, adipogenic and osteogenic gene expression levels in skeletal muscle between mdx mice and C57BL/6J mice were compared, with the purpose of investigating the underlying mechanism of pathological changes in skeletal muscle from mdx mice.METHODS : Frozen sections of skeletal muscle from mdx and C57BL/6J mice were prepared, stained with hematoxylin-eosin staining and Vonkossa staining. The morphological changes of the muscles were observed under microscope. Additionally, total RNA of skeletal muscle from mdx and C57BL/6J mice was extracted, reversed, and the expression levels of myogenic,adipogenic and osteogenic characteristic genes were examined by real-time PCR.RESULTS AND CONCLUSION: Necrosis and regeneration were found in skeletal muscles of mdx mice, and mild adipose hyperplasia and fibrous connective tissue hyperplasia were also observed. Moreover, calcium deposition nodules were easily detected by Vonkossa staining. The form of skeletal muscle cells from C57 mice was clear, and the nuclei were located in the cell periphery. Osteogenic and adipogenic gene expressions of skeletal muscle from mdx mice were elevated to a certain degree by real-time PCR (P < 0.05), compared with C57 mice, whereas myogenic gene expression was decreased (P< 0.05). The reason why adipocyte and osteoblast in skeletal muscle of mdx mice overgrew may be due to degeneration and necrosis of skeletal muscle which caused by dystrophin gene deletion, and it differentiates into osteoblasts and adipocytes instead of myoblasts.%背景:干细胞移植是治疗肌营养不良症的有效方法之一,

  15. Osteogenic and adipogenic differentiation of rabbit adipose-derived mesenchymal stem cells in vitro%体外培养兔脂肪源性间充质干细胞的成骨成脂分化

    Institute of Scientific and Technical Information of China (English)

    李受珉; 吴子征; 王泽; 李智; 张键

    2014-01-01

    wel as to investigate the osteogenic and adipogenic potentials of adipose-derived mesenchymal stem cells in vitro. METHODS:Primary adipose-derived mesenchymal stem cells were isolated from the subcutaneous adipose tissue of posterior cervical region from New Zealand white rabbits and digested by 0.1%col agenase I. The cells were passaged and amplified by the trypsin digestion. The passage 4 adipose-derived mesenchymal stem cells were induced to differentiate after exposure to adipogenic or osteogenic medium. The oil red O staining, alkaline phosphatase and alizarin red staining were used to detect the results. The cellviability was detected by the cellcounting kit 8 method to drawn the growth curve. cellsurface markers were examined using flow cytometry. RESULTS AND CONCLUSION:The adipose-derived mesenchymal stem cells isolated from the subcutaneous adipose tissue of rabbits exhibited a fusiform adherent growth in a vortex pattern, and had a strong capability of proliferation that could be passaged stably to the 10th generation. Flow cytometry results showed that the cells highly expressed CD29, CD90, CD44, but lowly expressed CD45 and CD34. After adipogenic induction, the adipose-derived mesenchymal stem cells were positive for oil red O staining;after osteogenic induction, the cells were both positive for alkaline phosphatase and alizarin red staining. These findings suggest that the adipose-derived mesenchymal stem cells were successful y isolated and cultured from the subcutaneous adipose tissue of rabbits, and these cells are pluripotent with the potential to differentiate into adipocytes and osteoblasts, which are expected to be ideal seed cells for bone tissue engineering.

  16. Regulated Extracellular Choline Acetyltransferase Activity- The Plausible Missing Link of the Distant Action of Acetylcholine in the Cholinergic Anti-Inflammatory Pathway.

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    Swetha Vijayaraghavan

    Full Text Available Acetylcholine (ACh, the classical neurotransmitter, also affects a variety of nonexcitable cells, such as endothelia, microglia, astrocytes and lymphocytes in both the nervous system and secondary lymphoid organs. Most of these cells are very distant from cholinergic synapses. The action of ACh on these distant cells is unlikely to occur through diffusion, given that ACh is very short-lived in the presence of acetylcholinesterase (AChE and butyrylcholinesterase (BuChE, two extremely efficient ACh-degrading enzymes abundantly present in extracellular fluids. In this study, we show compelling evidence for presence of a high concentration and activity of the ACh-synthesizing enzyme, choline-acetyltransferase (ChAT in human cerebrospinal fluid (CSF and plasma. We show that ChAT levels are physiologically balanced to the levels of its counteracting enzymes, AChE and BuChE in the human plasma and CSF. Equilibrium analyses show that soluble ChAT maintains a steady-state ACh level in the presence of physiological levels of fully active ACh-degrading enzymes. We show that ChAT is secreted by cultured human-brain astrocytes, and that activated spleen lymphocytes release ChAT itself rather than ACh. We further report differential CSF levels of ChAT in relation to Alzheimer's disease risk genotypes, as well as in patients with multiple sclerosis, a chronic neuroinflammatory disease, compared to controls. Interestingly, soluble CSF ChAT levels show strong correlation with soluble complement factor levels, supporting a role in inflammatory regulation. This study provides a plausible explanation for the long-distance action of ACh through continuous renewal of ACh in extracellular fluids by the soluble ChAT and thereby maintenance of steady-state equilibrium between hydrolysis and synthesis of this ubiquitous cholinergic signal substance in the brain and peripheral compartments. These findings may have important implications for the role of cholinergic

  17. Overfeeding energy upregulates peroxisome proliferator-activated receptor (PPAR)γ-controlled adipogenic and lipolytic gene networks but does not affect proinflammatory markers in visceral and subcutaneous adipose depots of Holstein cows.

    Science.gov (United States)

    Ji, P; Drackley, J K; Khan, M J; Loor, J J

    2014-01-01

    Our objective was to determine the effects of overfeeding energy on gene expression in mesenteric (MAT), omental (OAT), and subcutaneous (SAT) adipose tissue (AT) from nonpregnant and nonlactating Holstein cows. Eighteen cows were randomly assigned to either a low energy [LE, net energy for lactation (NE(L)) = 1.35 Mcal/kg of dry matter (DM)] or high energy (HE, NE(L) = 1.62 Mcal/kg of DM) diets for 8 wk. Cows were then euthanized and subsamples of MAT, OAT, and SAT were harvested for transcript profiling via quantitative PCR of 34 genes involved in lipogenesis, triacylglycerol (TAG) synthesis, lipolysis, lactate signaling, transcription regulation, and inflammation. The interaction of dietary energy and AT depot was only significant for LPL, which indicated a consistent response among the 3 sites. The expression of key genes related to de novo fatty acid synthesis (FASN) and desaturation (SCD) was upregulated by HE compared with LE. Other genes associated with those processes, such as ACLY, ACACA, ELOVL6, FABP4, GPAM, and LPIN1, were numerically upregulated by HE. The expression of lipolytic (PNPLA2 and ABHD5) genes was upregulated and the antilypolytic lactate receptor HCAR1 was downregulated with HE compared with LE. The putative transcription regulator THRSP was upregulated and the transcription regulator PPARG tended to be upregulated by HE, whereas SREBF1 was downregulated. Among adipocytokines, HE tended to upregulate the expression of CCL2, whereas IL6R was downregulated. Overall, results indicated that overfeeding energy may increase AT mass at least in part by stimulating transcription of the network encompassing key genes associated with de novo synthesis. In response to energy overfeeding, the expression of PPARG rather than SREBF1 was closely associated with most adipogenic or lipogenic genes. However, the transcriptional activity of these regulators needs to be verified to confirm their role in the regulation of adipogenesis or lipogenesis in bovine

  18. Structures of the N-acetyltransferase domain of Xylella fastidiosa N-acetyl-L-glutamate synthase/kinase with and without a His tag bound to N-acetyl-L-glutamate.

    Science.gov (United States)

    Zhao, Gengxiang; Jin, Zhongmin; Allewell, Norma M; Tuchman, Mendel; Shi, Dashuang

    2015-01-01

    Structures of the catalytic N-acetyltransferase (NAT) domain of the bifunctional N-acetyl-L-glutamate synthase/kinase (NAGS/K) from Xylella fastidiosa bound to N-acetyl-L-glutamate (NAG) with and without an N-terminal His tag have been solved and refined at 1.7 and 1.4 Å resolution, respectively. The NAT domain with an N-terminal His tag crystallized in space group P4(1)2(1)2, with unit-cell parameters a=b=51.72, c=242.31 Å. Two subunits form a molecular dimer in the asymmetric unit, which contains ∼41% solvent. The NAT domain without an N-terminal His tag crystallized in space group P21, with unit-cell parameters a=63.48, b=122.34, c=75.88 Å, β=107.6°. Eight subunits, which form four molecular dimers, were identified in the asymmetric unit, which contains ∼38% solvent. The structures with and without the N-terminal His tag provide an opportunity to evaluate how the His tag affects structure and function. Furthermore, multiple subunits in different packing environments allow an assessment of the plasticity of the NAG binding site, which might be relevant to substrate binding and product release. The dimeric structure of the X. fastidiosa N-acetytransferase (xfNAT) domain is very similar to that of human N-acetyltransferase (hNAT), reinforcing the notion that mammalian NAGS is evolutionally derived from bifunctional bacterial NAGS/K. PMID:25615976

  19. 糖基化终末产物对人牙周膜干细胞脂向分化相关基因C/EBPβ、PPAR-γ的影响%The effect of advanced glycation end products on the adipogenic differentiation of human periodontal ligament stem cells and its effect on C/EBPβ,PPAR-γexpression

    Institute of Scientific and Technical Information of China (English)

    邓超; 王云; 柳海; 周嵩琳; 伍燕; 刘琪

    2015-01-01

    Objective:To investigate the effect of advanced giycation end products ( AGEs) on the adipogenic differentiation of hu-man periodontai iigament stem ceiis (HPDLSCs) and detect the C/EBPβ,PPAR-γgene expression.Methods:HPDLSCs were isoiated by iimited diiution of cuiture ceiis for singie ceii cione .The osteogenic differentiation capacity of HPDLSCs was evaiuated by Aiizarin red staining,whiie the adipogenic differentiation capacity of HPDLSCs was evaiuated by oii red staining .HPDLSCs were induced with AGEs.Reai time quantitative reverse transcription poiymerase chain reaction (Reai time PCR) was performed to detect the differences of gene expression between the controi group and experimentai group .Results:After 21 days induction , Aiizarin red staining showed mineraiization noduies were formed .and oii red staining showed iipid dropiets were formed .After AGEs stimuiation , during HPDLSCs adipogenic differentiation ,the formation of iipid dropiets increased in the experimentai group .The expressions of CCAAT enhancer bind-ing protein β( C/EBPβ) and peroxisome proiiferator activated receptors γ( PPAR-γ) in the experimentai group were higher than those in the controi group.The differences were statisticaiiy significant (P<0.05).Conclusions:AGEs can promote the adipogenic differen-tiation capacity of HPDLSCs ,and change the expressions of C/EBPβ,PPAR-γmRNA ieveis.%目的:通过检测CCAAT/增强子结合蛋白β( C/EBPβ)、过氧化物酶体增殖物激活受体γ( PPAR-γ)基因的表达探讨糖基化终末产物(AGEs)对人牙周膜干细胞(HPDLSCs)脂向分化能力的影响. 方法:体外组织块法和有限稀释法克隆化培养人牙周膜干细胞;成骨、成脂诱导人牙周膜细胞,对其进行干细胞鉴定. 分别成脂诱导正常的人牙周膜干细胞和AGEs刺激下的人牙周膜干细胞,油红O染色观测两组细胞脂滴形成情况. 实时定量聚合酶链反应(Reai time PCR)检测成脂诱导后AGEs刺激下C

  20. 携带人胰岛素基因腺病毒载体转染人脐带间充质干细胞及其成脂分化*◆%Adipogenic differentiation of human umbilical cord mesenchymal stem cells transfected by insulin gene-modified adenovirus vector

    Institute of Scientific and Technical Information of China (English)

    李世龙; 刘毅; 惠玲

    2013-01-01

      背景:胰岛素是成脂诱导剂的重要组成成分。然而胰岛素存在半衰期,会随着体内代谢不断灭活及降解,植入体内的细胞或材料无法像体外那样以更换培养液来达到目的。实验拟通过转染胰岛素基因,使转染后的干细胞稳定分泌胰岛素,促进其成脂分化。目的:探讨携带人胰岛素基因腺病毒载体转染人脐带间充质干细胞后对其成脂分化能力的影响。方法:取第3代人脐带间充质干细胞,以感染复数为20转染腺病毒载体。实验分为4组:对照组为第4代人脐带间充质干细胞;实验组1为腺病毒转染的第4代人脐带间充质干细胞;实验组2为第4代人脐带间充质干细胞+成脂诱导液;实验组3为腺病毒转染的第4代人脐带间充质干细胞+成脂诱导液。结果与结论:转染48 h 后实验组1和实验组3的人脐带间充质干细胞在荧光显微镜下显现弱荧光,72 h后荧光较强。经脂肪诱导培养液培养14 d 后,实验组1,2,3油红 O 染色后显微镜下呈红色,对照组未见脂滴形成,实验组1可见一些细小脂滴形成;实验组3与实验组2相比,脂滴大且多,定量分析显示,实验组3油红 O 染色阳性的面积和吸光度大于实验组2(P <0.05)。由此说明携带人胰岛素基因腺病毒载体转染人脐带间充质干细胞后可促进其成脂能力。%BACKGROUND: Insulin is an important component of adipogenic inducers. Insulin has the half-life, which can continuously inactivate and degrade with the in vivo metabolism, and the cells and the materials implanted in the body cannot replace the culture medium to achieve the purpose like in in vitro environment. Transfection of insulin gene can make the transfected stem cells secret the insulin stably which can promote the adipogenic differentiation. OBJECTIVE: To investigate the adipogenic differentiation potential of human umbilical cord mesenchymal stem

  1. Association between hippocampal Choline acetyltransferase expression and cognition in diabetes mellitus rats%糖尿病大鼠海马胆碱乙酰转移酶表达与认知功能的相关性

    Institute of Scientific and Technical Information of China (English)

    张栋珉; 肖谦

    2009-01-01

    目的:观察糖尿病人鼠海马胆碱乙酰转移酶(ChAT)mRNA和蛋白表达及其与认知功能的关系,探讨糖尿病脑病的发病机制.方法:38只sD雄性大鼠随机分为正常对照组(C组)和糖尿病组(D组),腹腔注射链脲佐菌素建市糖尿病大鼠模型.建模成功后11 wk用Moms水迷宫测试大鼠学习和记忆能力;RT-PCR,原位杂交法检测ChAT mRNA表达;免疫组化,Western Blot法检测ChAT蛋白表达.结果:D组大鼠学习和记忆能力明显减退,其逃避潜伏期时间延长;c组40.90 4±10.90与D组77.56±27.86相比较,差异具有统计学意义(P<0.05).穿越目标区域次数c组(3.93±0.44)次与D组(1.37±0.85)次相比较明显减少(P<0.05);中心区域停留时间百分率c组(5.41±0.97)%与D组(2.20±1.28)%相比较明显下降(P<0.05).海马ChAT mRNA和ChAT蛋白表达c组0.48 4+0.03,0.55 4±0.02与D组0.37 4±0.01,0.33 4±0.01相比较均明显降低(P<0.05).结论:糖尿病大鼠海马ChAT mRNA和蛋白低水平表达可能是糖尿病脑病的发病机制之一.%AIM: To observe the relation between the expression of Choline acetyltransferase protein and mRNA of hippocampus and the cognitive function of diabetic rats and to explore the pathogenetic mechanism of diabetic encephalopathy. METHODS : Thirty eight SD male rats were randomly divided into normal control group (group C) and diabetic model group (group D). Diabetes was induced by a single peritoneal injection of streptozotocin. Eleven weeks later, learning and memory behaviors were investigated using a spatial version of the Morris water maze test. The expression of choline acetyhransferase mRNA in hippocampus was examined by RT-PCR and in situ hybridization. The expression of choline acetyhransferase protein was examined with immunohistochemistry and Western Blot. RESULTS: Compared with group C, group D showed a significant increase in the mean time of escape latencies ( P < 0.05 ) and a decrease in percentage of stay time in the central area

  2. 葛根素抑制酒精导致人骨髓间充质干细胞的成脂分化%Inhibitory effect of puerarin on adipogenic differentiation of alcohol-induced human bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    杨妍; 于雅丽; 杨春喜; 李晓坤; 王义生; 李月白

    2009-01-01

    背景:葛根素属异黄酮类物质,研究发现其具有减轻酒精毒性和酒精成断症状的作用,此外还可以抗氧化、清除组织及细胞产生的氧自由基、减轻脂质过氧化对细胞的损害.目的:探讨葛根素对酒精导致的人骨髓间充质干细胞成脂分化的抑制作用.设计、时间及地点:细胞学体外观察,于2008-10在郑州大学基础医学院生物化学与分予牛物学教研室实验室完成.材料:骨髓取自健康成人志愿者,由郑州大学第一附属医院骨科提供.葛根素标准品由中国药品生物制品检定所提供.方法:采用梯度离心法分离培养入骨髓间充质干细胞,取传2代细胞,随机分为3组:空白对照组加入含体积分数为10%胎牛血清的DMEM培养基;模型组每天加入乙醇0.09 mol/L;实验组每天加入酒精0.09 mol/L,每两三天更换培养液时加入葛根素10-6moll/L.各组细胞培养7d.主要观察指标:采用RT-PCR法检测PPAR-γ2基因的表达,油红"O"染色进行脂肪细胞计数,测定细胞内碱性磷酸酶活性.结果:模型组PPAR-γ2 mRNA呈高表达,明显高于实验组和空白对照组(P<0.05);实验组PPAR-γ2mRNA表达略高于对照组,但差异无显著性意义(P>0.05).模型组脂肪细胞最多,细胞内脂滴大而丰富;实验组脂肪细胞较模型组显著减少(P<0.05);空白对照组脂肪细胞极少.与窄白对照组比较,模型组细胞内碱性磷酸晦活性明显降低(P<0.05);与模型组比较.实验组细胞内碱性磷酸酶活性明显升高(P<0.05).结论:葛根素能抑制酒精导致的骨髓间充质干细胞向脂肪细胞分化.%BACKGROUND:Pueraria is a member of isoflavone characterizing by decreasing the toxic effects of alcohol,relieving the effect of alcohol withdrawal,anti-oxidative effect,removing oxygen free radicals,and preventing cell injury induced by lipid peroxidation.OBJECTIVE:To investigate the inhibitory effect of puerarin on adipogenic differentiation of

  3. Isolation, expansion and adipogenic differentiation of human keloid-derived precursor cells%人体瘢痕疙瘩前体细胞的分离培养及向脂肪细胞的定向诱导分化

    Institute of Scientific and Technical Information of China (English)

    林珣珣; 刘杰; 李付贵; 武日东; 唐诗; 唐庆

    2013-01-01

    目的 研究人体瘢痕疙瘩来源的前体细胞(keloid-derived precursor cell,KPC)的体外分离、扩增方法,及其在特定培养基条件下向脂肪细胞的诱导分化,探讨其作为组织工程脂肪种子细胞的可能性.方法 取人体瘢痕疙瘩组织在改良L-DMEM培养基条件下培养,传代后以流式细胞仪检测其间充质干细胞(mesenchymal stem cell,MSC)相关基因表达,并以特定H-DMEM培养基[含1 μmol/L的地塞米松,0.5 mmol/L的3异丁基-1甲基黄嘌呤(3-IBMX),10 mg/L牛胰岛素,100 mmol/L的消炎痛,10%的胎牛血清(FBS)]诱导,在相差显微镜下观察,油红O染色测定脂滴生成.结果 超过95%的KPC表达CD29、CD44、CD90/Thy-1和CD105;几乎不表达CD45和CD34(1.0%~2.5%);且诱导后该细胞渐增大,由梭形变为圆形或多角形,72 h出现脂滴,19d油红O染色细胞阳性率78.6%.结论 KPC能表达多种MSC表面标志物,不表达造血干细胞(hemopoietic stem cell,HSC)标志物,能够在诱导培养基条件下分化为脂肪细胞,可能成为组织工程脂肪的一种新种子细胞来源.%Objective To explore the isolation,amplification methods and adipogenic differentiation under specific culture medium of human keloid-derived precursor cell (KPC) in vitro,in order to study their possibility of being new seed cells of tissue engineering fat.Methods KPCs were isolated from human keloid tissue of 4 different patients in our hospital and were cultured in the modified L-DMEM culture medium.Their cloning efficiency and growth curve were tested.The subcultured cells were tested of the mesenchymal stem cell (MSC)-related gene expression by flow cytometry.In addition,they were cultured in H-DMEM medium (containing 1 μmol/L dexamethasone,0.5 mmol/L 3-isobutyl-1-methyl-xanthine 10 mg/L of bovine insulin,100 mmol/L indomethacin,and 10 % FBS)and were later observed in oil red O staining under phase contrast microscope to determine whether lipid droplets generation was

  4. Adipogenic and tenogenic differentiation of tendon-derived stem cells isolated from an animal model of chronic tendinopathy in vitro%慢性腱病模型大鼠肌腱干细胞体外成脂和成肌腱的分化能力

    Institute of Scientific and Technical Information of China (English)

    陈辉; 林禹丞; 徐宏亮; 王宸; 芮云峰

    2014-01-01

    BACKGROUND:Chronic tendinopathy is a tendon disorder extremely common in athletes and in the general population with repetitive strain injuries of tendons. The pathogenesis of tendinopathy remains unclear and hence treatment of tendinopathy is usual y pal iative. OBJECTIVE:To investigate the of adipogenic and tenogenic ability of patel ar tendon-derived stem cel s isolated from chronic tendinopathy and healthy rats in vitro. METHODS:Tendon-derived stem cel s were isolated from patel ar tendons of chronic tendinopathy and healthy rats respectively. The tendon-derived stem cel s were cultured to the 3rd passage in complete culture medium, and cel morphology was observed. The cel s were divided into adipogenic induction group and control group. Cel s in the adipogenic induction group were cultured in adipogenic induction medium, while those in the control group cultured in complete culture medium. The ability of adipogenic differentiation between tendon-derived stem cel s isolated from the tendon of chronic tendinopathy and healthy rats in vitro was examined by oil red O staining and quantification assay. The mRNA expressions of C/EBPαand PPARγ2 were detected by real-time quantitative PCR. When 70%-80%cel s were confluent, the mRNA expressions of Col1a1, Scx, Tnmd and Dcn were also detected by real-time quantitative PCR. RESULTS AND CONCLUSION:At the third passage, slender spindle-shaped cel s were seen in both two groups, but there was a little change in the cel morphology in the chronic tendinopathy group. Lipid droplets were formed after the cel s were cultured in adipogenic induction medium for 21 days. This was not observed in the control group. We observed more oil red O-positive oil droplets in tendon-derived stem cel s from the tendons of chronic tendinopathy rats than healthy rats. The difference between them was statistical y significant (P=0.004). The results of real-time quantitative PCR showed that the mRNA expressions of C/EBPαand PPARγ2 in the

  5. NAT2*6A,a haplotype of the N-acetyltransferase 2 gene, is an important biomarker for risk of anti-tuberculosis drug-induced hepatotoxicity in Japanese patients with tuberculosis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate an association between N-acetyltransferase 2 (NAT2)-haplotypes/diplotypes and adverse effects in apanese pulmonary tuberculosis patients.METHODS: We studied 100 patients with pulmonary TB treated with anti-TB drugs including INH. The frequencies and distributions of single nucleotide polymorphisms, haplotypes, and diplotypes of NAT2 were determined by the PCR-restriction fragment length polymorphism method, and the results were compared between TB patients with and without adverse effect,using multivariate logistic regression analysis.RESULTS: Statistical analysis revealed that the frequency of a variant haplotype, NAT2*6A, was significantly increased in TB patients with hepatotoxicity,compared with those without hepatotoxicity [P = 0.001,odds ratio (OR) = 3.535]. By contrast, the frequency of a wild-type (major) haplotype,"NAT2*4″, was significantly lower in TB patients with hepatotoxicity than those without hepatotoxicity (P < 0.001, OR = 0.265).There was no association between NAT2-haplotypes and skin rash or eosinophilia.CONCLUSION: The present study shows that NAT2 is one of the determinants of anti-TB drug-induced hepatotoxicity. Moreover, the haplotypes, NAT2*4 and NAT2*6A, are useful new biomarkers for predicting antiTB drug-induced hepatotoxicity.

  6. In vitro effects of steroid hormones on arylalkylamine N-acetyltransferase (AA-NAT) activity in the pineal of fish, Clarias gariepinus (Burchell, 1822) during different phases of breeding cycle.

    Science.gov (United States)

    Yanthan, L; Gupta, B B P

    2007-08-01

    In vitro effects of gonadal hormones (testosterone, 17beta-estradiol estriol and estrone) and corticosteroid hormones (corticosterone and cortisol) were studied on arylalklyamine N-acetyltransferase (AA-NAT) activity in the pineal organ of the fish, C. gariepinus during quiescent, progressive, breeding and regressive phases of its annual breeding cycle. The pineals were collected under dim red light, maintained in organ culture for 7 hr and incubated with three concentrations (10(-6), 10(-5) and 10(-4) M) of hormones for 6 hr. The treatments with gonadal hormones and corticosteroid hormones inhibited pineal AA-NAT activity in a dose-dependent manner during all the phases of the breeding cycle. AA-NAT activity was comparatively more sensitive to the inhibitory effects of the gonadal hormones during the regressive phase and less sensitive during the quiescent phase. Further, the enzyme activity was more sensitive to the inhibitory effects of corticosteroid hormones (corticosterone and cortisol) during the breeding phase and less sensitive during the quiescent phase. These findings seem to suggest that gonadal hormones and corticosteroid hormones have direct inhibitory influence on AA-NAT activity and, hence melatonin synthesis in the photoreceptive pineal organ of C. gariepinus.

  7. Osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells under directional induction%定向诱导分化环境下骨髓间充质干细胞向成骨及成脂细胞的分化

    Institute of Scientific and Technical Information of China (English)

    赵勤鹏

    2015-01-01

    BACKGROUND:Bone marrow mesenchymal stem cels are non-hematopoietic stem cels from the bone marrow and can differentiate into chondrocytes, osteocytes and adipocytes under different induction conditions, which are the most promising seed cels for tissue engineering. OBJECTIVE:To evaluate the osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cels under directional induction. METHODS:Bone marrow samples from Japanese rabbits were extracted asepticaly to isolate and purify bone marrow mesenchymal stem cels using density gradient centrifugation and cel adherent method. Then, the cels were cultured in osteogenic and adipogenic induction media as experimental group. Another cels cultured in DMEM medium acted as control group. Sudan IV staining, Von Kossa staining and alkaline phosphatase activity detection were performed at different time after culture to compare the osteogenic and adipogenic rates. RESULTS AND CONCLUSION:After 7 days of adipogenic induction, smal lipid droplets were visible and the cels arranged disorderly; at 21 days of induction, see lipid droplets with high refractivity were seen in the cytoplasm. Sudan IV staining showed that there were a large amount of red lipid droplets in the cloning center of bone marrow mesenchymal stem cels, but only 5% bone marrow mesenchymal stem cels differentiated into adipocytes in the control group. At 7 days of osteogenic induction, induced cels were confluent in a flagstone shape, and there were many nodules; at 14 days of culture, the center of brown mineralized nodules were visible; at 21 days of culture, smal pieces of mineralized nodules formed. The osteogenic and adipogenic rates were 40% and 20% in the experimental group, respectively, which were higher than those in the control group (5%, 5%). These findings indicate that under certain conditions, bone marrow mesenchymal stem cels can partialy differentiate into fat cels part, and another part differentiate into osteocytes, suggesting

  8. 不同传代倍数人羊膜来源的间充质干细胞成骨成脂分化平衡的研究%Research on balance between osteogenic and adipogenic differentiation of human amnion - derived mesenchymal stem cells of different passage numbers

    Institute of Scientific and Technical Information of China (English)

    陈霞; 尹晓娟

    2011-01-01

    Objective To compare proliferative activity, osteogenic and adipogenic differentiation capacity among different passage numbers of human amniotic mesenchymal stem cells( hAMSCs ). Methods The hAMSCs were isolated from human placental basal decidua hy collagenase and trypsinase digestion methods. The superficial molecular markers of these cells were detected hy flow cytometry. After serial passage , passage 3 ,5 ,7 ,9( P3 , P5 , P7 , P9 )were singled out for the assay of proliferative activity by MTT method and the findings were delineated as growth curve. Furthermore, these cells of above four passages were respectively induced by adding osteogenic and adipogenic inducers. 3 w later, intracellular lipid deposition was verified by oil red O staining and extracellular calciumphosphate precipitates were stained with alizarin red. The positive rate of osteogenic staining and adipogenic rate were compared among different passage numbers of hAMSCs. Results hAMSCs of P9 still showed a colony - like growth property , but their proliferative activity was down regulated. Intracellular lipid droplets decreased from P5( P < 0.01 ). and extracellular calciumphosphate did from P7( P< 0.01 ). Conclusion hAMSCs can keep growth characteristics of mesenchymal stem cells during serial passage. However,multipotential differentiation capacity is varied among different passage numbers.%目的 比较不同传代倍数的人羊膜来源的间充质干细胞(hAMSCs)的增殖活性以及成骨、成脂的分化能力.方法 采用胶原酶和胰蛋白酶法分离人胎盘羊膜来源的MSCs,测定分离细胞的表面分子标志.对第3、5、7、9代hAMSCs绘制细胞生长曲线,分别加入成骨和成脂诱导剂,诱导3 w后行茜素红和油红O染色,比较不同传代倍数的hAMSCs成骨染色阳性率和成脂率.结果 hAMSCs传代至第9代时仍呈克隆样生长,但细胞增殖活力有下降;在第5代后成骨分化能力下降(P<0.01),而传代至第7代后,成

  9. Relationship between genetic polymorphism of N-acetyltransferase and early-onset Parkinson disease%N-乙酰基转移酶基因多态性与早发性帕金森病关系的研究

    Institute of Scientific and Technical Information of China (English)

    刘平; 杨静芳; 董秀敏; 陈彪; 邵明; 刘振华; 郭艳平

    2001-01-01

    Objective To investigate the relationship between the slowacetylator genotype induced by the genetic polymorphism of N-acetyltransferase 2 (NAT2) gene and the early-onset Parkinson disease. Methods Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used and three mutant alleles M1, M2 and M3 of NAT2 were studied in 126 patients with idiopathic early-onset Parkinson disease and 122 age-matched randomly selected controls. Results The frequencies of alleles M1, M2 and M3 of NAT2 in patients were 8.7%,26.6% and 13.1%,respectively,however,there were 2.9%,19.7% and 14.8% in controls, respectively. The difference in frequency of allele M1 was statistically significant(P=0.005). The frequency of slow acetylator genotype was higher in patients (23.0%) than in controls (10.7%), showing an OR of 2.507(P=0.009). Conclusion Our study suggests that the slow acetylator genotype of N-acetyltransferase 2 might be associated with the occurrence of the idiopathic early-onset Parkinson′s disease.%目的 探讨N-乙酰基转移酶基因(NAT2)的多态性所导致的慢乙酰化基因型与早发性帕金森病(PD)的关系。方法 利用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)技术分析了126例早发性帕金森病患者(发病年龄≤50岁)与122名正常健康成人对照组NAT2基因3个常见突变的等位基因M1、M2、M3的分布频率,比较慢乙酰化基因型在早发性PD病人与正常人之间的分布差异。结果 等位基因M1、M2、M3在病例组中的分布频率分别为8.7%、26.6%、13.1%;在对照组中为2.9%、19.3%、14.8%,等位基因M1在两组中之间差异有显著意义(P=0.005)。病例组慢乙酰化型基因频率为23.0%,对照组为10.7%,两者差异有显著意义(P=0.009)。OR值为2.507。结论 N-乙酰基转移酶慢乙酰化基因型可能与早发性PD的发病有关。

  10. Structural characterization of Streptococcus pneumoniae serotype 9A capsule polysaccharide reveals role of glycosyl 6-O-acetyltransferase wcjE in serotype 9V capsule biosynthesis and immunogenicity.

    Science.gov (United States)

    Calix, Juan J; Saad, Jamil S; Brady, Allison M; Nahm, Moon H

    2012-04-20

    The putative capsule O-acetyltransferase gene wcjE is highly conserved across various Streptococcus pneumoniae serotypes, but the role of the gene in capsule biosynthesis and bacterial fitness remains largely unclear. Isolates expressing pneumococcal serotype 9A arise from precursors expressing wcjE-associated serotype 9V through loss-of-function mutation to wcjE. To define the biosynthetic role of 9V wcjE, we characterized the structure and serological properties of serotype 9V and 9A capsule polysaccharide (PS). NMR data revealed that both 9V and 9A PS are composed of an identical pentasaccharide repeat unit, as reported previously. However, in sharp contrast to previous studies on 9A PS being devoid of any O-acetylation, we identified O-acetylation of α-glucuronic acid and α-glucose in 9A PS. In addition, 9V PS also contained -CH(2) O-acetylation of β-N-acetylmannosamine, a modification that disappeared following in vitro recombinatorial deletion of wcjE. We also show that serotyping sera and monoclonal antibodies specific for 9V and 9A bound capsule PS in an O-acetate-dependent manner. Furthermore, IgG and to a lesser extent IgM from human donors immunized with serotype 9V PS displayed stronger binding to 9V compared with 9A PS. We conclude that serotype 9V wcjE mediates 6-O-acetylation of β-N-acetylmannosamine. This PS modification can be selectively targeted by antibodies in immunized individuals, identifying a potential selective advantage for wcjE inactivation and serotype 9A emergence.

  11. Genetic polymorphism of N-acetyltransferases, glutathione S-transferase M1 and NAD(P)H:quinone oxidoreductase in relation to malignant and benign pancreatic disease risk. The International Pancreatic Disease Study Group.

    Science.gov (United States)

    Bartsch, H; Malaveille, C; Lowenfels, A B; Maisonneuve, P; Hautefeuille, A; Boyle, P

    1998-06-01

    Carcinogens present in cigarette smoke and diet have been associated with pancreatic cancer. We hypothesized that heterocyclic and aromatic amines implicated in these exposures could be involved as causative agents and that therefore genetic variation in enzymes metabolizing these carcinogens could modify the risk of developing malignant and benign pancreatic disease. The effect of the genetic polymorphism of acetyltransferases (NAT1) and NAT2), glutathione S-transferase M1 (GSTM1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) on the risk of pancreatic diseases (cancer, pancreatitis) was examined in a case-control study. PCR-based assays were used for genotype analysis of genomic DNA from whole blood cells. Samples collected from Caucasian patients with diagnosed pancreatic cancer (n = 81), with non-alcoholic (n = 41) and alcoholic pancreatitis (n = 73) and from asymptomatic control subjects (n = 78) were analysed. The prevalence of GSTM1 null genotype and of NAT2 fast and slow acetylator genotypes and the distribution of frequencies for NQO1 genotypes did not differ in subjects with pancreatic diseases vs controls. For NAT1 slow acetylators a non-significant excess (P = 0.18) was found among pancreatic cancer cases vs controls. There was a significant over-representation of the GSTM1 AB or B genotype in all pancreatic disease cases combined (OR = 2.6; P < 0.05). When concurrent controls were pooled with literature controls (n = 1427), OR was 1.4 (P = 0.08). The results of this study, requiring confirmation, suggest that the polymorphism of GSTM1 and NAT1 enzymes may be associated with a modest increase in susceptibility to pancreatic diseases. PMID:9696930

  12. 组织工程室内血管化和成脂化诱导微环境对脂肪组织再生的影响%The impact of angiogenic and adipogenic microenvironment on adipose tissue regeneration in tissue engineering chamber

    Institute of Scientific and Technical Information of China (English)

    鲁峰; 詹炜卿; 常强; 黎小间

    2014-01-01

    目的 通过研究组织工程室内血管化和成脂化诱导微环境对新生脂肪组织的组织形态及结构的影响,探讨组织工程室模型成功诱导成熟脂肪组织新生的关键因素.方法 健康6个月龄新西兰大白兔24只,根据不同的诱导环境,应用组织工程室技术建立4种兔模型,每组6只:无轴型血供脂肪瓣组(脂肪组织原始体积记为0 ml)、单纯颗粒脂肪组(取0.6 ml对侧脂肪垫)、单纯轴型血管蒂组(原始血管蒂组织为0.05 ml)和轴型血管蒂脂肪瓣组(0.6 ml带蒂脂肪瓣).对血管化和成脂化诱导微环境进行分离或组合,8周后取出标本,观察大体形态,测量新生组织体积,并进行HE染色,观察组织形态学.采用SPSS 13.0统计软件分析,术前与术后8周脂肪瓣体积大小、毛细血管数目采用配对t检验.结果 8周后,单纯颗粒脂肪组体积减小为(0.25±0.10) ml,最终脂肪颗粒被机体包膜包裹机化,难以诱导成熟脂肪组织新生;单纯轴型血管蒂组体积增加至(0.37±0.04) ml,但最终形成的组织只是纤维结缔组织;无轴型血供脂肪瓣组体积为(0.12±0.03) ml,由于基底缺少独立的血供,不足以支持大体积的脂肪组织新生;轴型血管蒂脂肪瓣组成功诱导出大块成熟脂肪组织新生,体积为(3.45±0.48) ml.8周后各组新生的毛细血管数目各不相同,每单一视野下计数后,无轴型血管供应的脂肪瓣组(15±3.5)个和单纯颗粒脂肪组(5±2.5)个分别与轴型血管蒂脂肪瓣组(22±5)个之间比较,差异均有统计学意义(P<0.05).结论 在组织工程室模型中,只有同时提供独立的血供和成脂微环境,才能最终诱导大体积的成熟脂肪组织新生.%Objective By observing the adipogenic and angiogenic microenvironment impact on the morphology of newly generated tissue for exploring the key factors which inducing mature adipose tissue regeneration in tissue engineering model.Methods 24 healthy 6 months' New

  13. The Effect of Simulated Microgravity on Proliferation and Adipogenic Differentiation Capacity of Bone Marrow Mesenchymal Stem Cells%模拟微重力对骨髓间充质干细胞增殖及其向脂肪方向分化能力的影响

    Institute of Scientific and Technical Information of China (English)

    王南丁; 张晓凤; 陈艳秋; 南亚昀; 司静文; 王宗仁; 王文

    2013-01-01

    Objective: To investigate the effect of simulated microgravity on proliferation and adipogenic differentiation capacity of bone marrow mesenchymal stem cells (BMSCs). Methods: Part one: BMSCs were divided into two groups: normal gravity(NG) group and simulated microgravity (SMG) group (with clinostat-rotation, 30r/min). After the cells cultured for 72h, the proliferation of two groups MSCs were detected by BrdU incorporation assay. The growth curves were evaluated by cell counting. The expression of Oct4 and SSEA4 was analyzed by Western Blot. Part two: the MSCs were divided into three groups: the first group cells were induced in the NG condition with the adipogenic media after cultured in NG 72h. The second group cells were induced in the NG condition after cultured in SMG 72h and the third group were induced in the SMG condition after cultured in SMG 72 h. After 7 days, fresh oil red O solution staining was applied to examine the efficiency of adipogenic induction. Western Blotting analyzed the expression of Oct4 and PPARγ2. Results: Part one: Flow Cytometry showed the percent of BrdU+ cell was higher in SMG group than that in NG group and the attachment rate of MSCs under SMG condition was obviously higher than that under NG condition (P<0.05). Western Blotting showed cells expressed much more Oct4 and SSEA4 in SMG group than that in NG group. Red-oil O solution staining found there were more adipocyte -like cells in the second group than in the first group, but the third group nearly had no adipocyte -like cell. Western Blotting showed the higher expression of PPARγ2 in the second group was significant, compared with that in the first group, the third group only expressed little PPARγ2. In addition, Oct4 expressed more in the third group by contrasted with the little expression in the first and the second groups. Conclusion: The simulated microgravity could potentiate proliferation of BMSCs and enhance their adipogenic differentiation capacity by

  14. 褪黑素对异氟醚麻醉大鼠海马胆碱乙酰基转移酶的影响%Effects of melatonin on choline acetyltransferase in rat hippocampus after isoflurane anesthesia

    Institute of Scientific and Technical Information of China (English)

    倪诚; 谭刚; 罗爱伦

    2014-01-01

    Objective To investigate the effects of melatonin on choline acetyltransferase (ChAT) in the hippocampus of rats after isoflurane anesthesia.Methods Sixty male SD rats weighing 390-440 g were randomized into five groups (n =12 each):control group (group C),1% isoflurane group (group Ⅰ),1% isoflurane + melatonin group (group IM),2% isoflurane group (group J) and 2% isoflurane + melatonin group (group JM).Rats in groups IM and JM received intraperitoneal injection of melatonin (10 mg/kg) for 7 days,and rats in other groups received normal saline.On the 7th day of injection,rats in groups Ⅰ and IM inhaled 1% isoflurane for 4 hours,and rats in groups J and JM inhaled 2% isoflurane for 4 hours.One day after anesthesia,all the rats began Morris water maze to assess the learning and memory ability,which was made for continuous 5 days.At the end of probe test,6 rats in each group were randomly selected,blood samples were collected to detect plasma melatonin level,and the hippocampi were removed to evaluate the expression and activity of ChAT.The other rats were sacrificed to perform immunofluorescence to detect ChAT in hippocampal CA1 region and dentate gyrus.Results The plasma melatonin level,and the expression and activity of ChAT were significantly lower in group Ⅰ than in group C (P < 0.01).The escape latency was significantly longer,the probe time was significantly shorter,and the plasma melatonin level and the expression and activity of ChAT were significantly lower in group J than in group C (P < 0.05 or 0.01).The escape latency was significantly shorter,the probe time was significantly longer,and the plasma melatonin level and the expression and activity of ChAT were significantly higher in group IM than in group Ⅰ (P < 0.05 or 0.01).The escape latency was significantly shorter,and the plasma melatonin level and the ChAT activity were significantly higher in group JM than in group J (P< 0.05 or 0.01).Conclusion Melatonin can attenuate

  15. Anti-diabetic and anti-adipogenic effects of a novel selective 11β-hydroxysteroid dehydrogenase type 1 inhibitor, 2-(3-benzoyl)-4-hydroxy-1,1-dioxo-2H-1,2-benzothiazine-2-yl-1-phenylethanone (KR-66344).

    Science.gov (United States)

    Park, Ji Seon; Rhee, Sang Dal; Kang, Nam Sook; Jung, Won Hoon; Kim, Hee Youn; Kim, Jun Hyoung; Kang, Seung Kyu; Cheon, Hyae Gyeong; Ahn, Jin Hee; Kim, Ki Young

    2011-04-15

    The selective inhibitors of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) have considerable potential for treating type 2 diabetes mellitus and metabolic syndrome. In the present study, we investigated the anti-diabetic and anti-adipogenic effects of 2-(3-benzoyl)-4-hydroxy-1,1-dioxo-2H-1,2-benzothiazine-2-yl-1-phenylethanone (KR-66344), as a 11β-HSD1 inhibitor; we also investigated the underlying molecular mechanisms in the cortisone-induced 3T3-L1 adipogenesis model system and C57BL/6-Lep(ob/ob) mice. KR-66344 concentration-dependently inhibited 11β-HSD1 activity in human liver microsome, mouse C2C12 myotube and human SW982 cells. In the C57BL/6-Lep(ob/ob) mice study, the administration of KR-66344 (200mg/kg/d, orally for 5 days) improved the glucose intolerance as determined by the oral glucose tolerance test, in which the area under the curve (AUC) of the plasma glucose concentration was significantly reduced by 27% compared with the vehicle treated group. Further, KR-66344 suppressed adipocyte differentiation on cortisone-induced adipogenesis in 3T3-L1 cells is associated with the suppression of the cortisone-induced mRNA levels of FABP4, G3PD, PPARγ2 and Glut4, and 11β-HSD1 expression and activity. Our results additionally demonstrate evidence showing that KR-66344 improved glycemic control and inhibited adipogenesis via 11β-HSD1 enzyme activity. Taken together, these results may provide evidence of the therapeutic potential of KR-66344, as a 11β-HSD1 inhibitor, in obesity and type 2 diabetes patients with metabolic syndrome.

  16. 2-Amino-3,8-dimethylimidazo-[4,5-f]quinoxaline-induced DNA adduct formation and mutagenesis in DNA repair-deficient Chinese hamster ovary cells expressing human cytochrome P4501A1 and rapid or slow acetylator N-acetyltransferase 2.

    Science.gov (United States)

    Bendaly, Jean; Zhao, Shuang; Neale, Jason R; Metry, Kristin J; Doll, Mark A; States, J Christopher; Pierce, William M; Hein, David W

    2007-07-01

    2-Amino-3,8-dimethylimidazo-[4,5-f]quinoxaline (MeIQx) is one of the most potent and abundant mutagens in the western diet. Bioactivation includes N-hydroxylation catalyzed by cytochrome P450s followed by O-acetylation catalyzed by N-acetyltransferase 2 (NAT2). In humans, NAT2*4 allele is associated with rapid acetylator phenotype, whereas NAT2*5B allele is associated with slow acetylator phenotype. We hypothesized that rapid acetylator phenotype predisposes humans to DNA damage and mutagenesis from MeIQx. Nucleotide excision repair-deficient Chinese hamster ovary cells were constructed by stable transfection of human cytochrome P4501A1 (CYP1A1) and a single copy of either NAT2*4 (rapid acetylator) or NAT2*5B (slow acetylator) alleles. CYP1A1 and NAT2 catalytic activities were undetectable in untransfected Chinese hamster ovary cell lines. CYP1A1 activity did not differ significantly (P > 0.05) among the CYP1A1-transfected cell lines. Cells transfected with NAT2*4 had 20-fold significantly higher levels of sulfamethazine N-acetyltransferase (P = 0.0001) and 6-fold higher levels of N-hydroxy-MeIQx O-acetyltransferase (P = 0.0093) catalytic activity than cells transfected with NAT2*5B. Only cells transfected with both CYP1A1 and NAT2*4 showed concentration-dependent cytotoxicity and hypoxanthine phosphoribosyl transferase mutagenesis following MeIQx treatment. Deoxyguanosine-C8-MeIQx was the primary DNA adduct formed and levels were dose dependent in each cell line and in the following order: untransfected < transfected with CYP1A1 < transfected with CYP1A1 and NAT2*5B < transfected with CYP1A1 and NAT2*4. MeIQx DNA adduct levels were significantly higher (P < 0.001) in CYP1A1/NAT2*4 than CYP1A1/NAT2*5B cells at all concentrations of MeIQx tested. MeIQx-induced DNA adduct levels correlated very highly (r2 = 0.88) with MeIQx-induced mutants. These results strongly support extrahepatic activation of MeIQx by CYP1A1 and a robust effect of human NAT2 genetic polymorphism

  17. 电刺激大鼠皮层桶状区对胆碱乙酰移位酶表达的影响%Expression of choline acetyltransferase in the rat barrel cortex by electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    樊红琨; 杨春; 张艳燕; 乐小平; 郑春光; 师黎; 章茜

    2013-01-01

    目的:观察电脉冲刺激大鼠大脑皮层桶状区(BC)诱导的转向运动,并观察电刺激后胆碱乙酰移位酶(ChAT)在大鼠BC区的表达.方法:将大鼠随机分为3组:空白组、对照组、实验组.对照组和实验组大鼠在双侧BC区埋植刺激电极;术后7d实验组大鼠给予电刺激诱导左右转向运动;连续刺激3d后,取脑行冰冻切片常规HE染色和免疫组织化学染色;并提取3组大鼠海马和脑组织蛋白,用Western blot方法检测ChAT的表达.结果:给予电脉冲刺激大鼠BC区,实验动物均出现向左或向右转;HE染色显示电极周围组织没有明显形态学变化.与对照组和空白组相比,免疫组化和Western blot结果均显示实验组大鼠BC区ChAT阳性的表达率增高.结论:电刺激BC区可诱导大鼠产生特定的方向性运动;且大鼠脑组织中ChAT表达增加,提示胆碱能神经递质参与了感觉-运动皮层之间的信息传递.%Objective:To observe a turning performance in the rats excited by using a proper electrical stimuli of the barrel cortex region (BC),and the expression of choline acetyltransferase (ChAT) in the BC regions after electoral stimulation.Methods:SD rats were divided into three groups.The stimulation electrodes were surgically implanted into the bilateral BC regions in the control group and the experimental group rats.The experiment group post surgery for seven days was given the electrical impulses via connection with the electrodes for three times each day through consecutive three days.Three groups of the rats were killed and the brains were quickly removed for frozen sections and then perfomed with conventional HE and immunohistochemistry staining.And protein samples were prepared from brain and the hippocampus tissues of the three groups to detect the level of the ChAT protein by Western blot.Results:The experimental rats turn left or right when continuously stimulation in the bilateral BC regions with electric pulse

  18. RELATIONSHIP BETWEEN GENETIC POLYMORPHISMS OF N- ACETYLTRANSFERASE 2 AND SUSCEPTIBILITY OF BREAST CANCER IN SHANDONG DISTRICT%山东地区NAT2基因多态性与乳腺癌易感性的研究

    Institute of Scientific and Technical Information of China (English)

    王萍玉; 谢书阳; 张超; 高宗华

    2011-01-01

    [目的]研究NAT2基因多态性与乳腺癌易感性的关系.[方法]采用1:1配对病例-对照研究,对山东地区100例乳腺癌患者和100例健康对照者采用聚合酶链反应-限制性片段长度多态性分析(PCR- RFLP),检测NAT2基因多态性,分析NAT2基因多态性与乳腺癌易感性之间的关系.[结果]携带NAT2/5B等位基因者患乳腺癌 危险性增加(OR=2.38, 95%CI=1.54~3.67);幔基因型者患乳腺癌的危险性是快基因型者2.28倍(OR=2.28,95%CI=1.12~4.63);是中间基因型者2.14倍(OR=2.14,95%CI=1.08~4.24);慢型乙酰化患乳腺癌的危险性是快型乙酰化的2.11倍(OR=2.11, 95%CI=1.15-3.88).[结论]NAT2基因多态性在乳腺癌的遗传发病机制中起重要作用,携带NAT2/5B等位基因、慢基因型及慢型乙酰化能增加患乳腺癌的易感性.%[Objective] To evaluate the possible relationship between N-acetyltransferase 2 (NAT2) polymorphisms and breast cancer. [Methods] In the 1: 1 matched case-control study, NAT2 genotypes were determined by PCR-RFLP method in 100 patients with breast cancer and 100 healthy controls. The possible relationship between NAT2 polymorphisms and lung cancer risk was analyzed. [Results] NAT2*5B allele was associated with an increased risk of breast cancer (odds ratio (OR) 2.38 (95% confidence interval (95%Cl) 1.54-3.67; slow genotype was 2.28 times to rapid genotype (OR = 2.28, 95%CI= 1.12-4.63) and 2.14 times to intermediate genotype (OR - 2.14, 95%C/=1.08-4.24); and NAT2 slow acetylates increased risk of breast cancer (OR = 2.11, 95%C/ = 1.15-3.88). [Conclusion] These findings suggest that NAT2 genetic polymorphism may be associated with breast cancer susceptibility. People with NAT2*5B allele or NAT2 slow genotype or NAT2 slow acetylates have higher breast cancer risk.

  19. Construction of a doxycycline inducible adipogenic lentiviral expression system

    OpenAIRE

    Liu, Q.; Hill, P J; Karamitri, Angeliki; Ryan, K.J.P.; Chen, H. Y.; Lomax, Michael A.

    2013-01-01

    To provide a tool for research on regulating adipocyte differentiation, tetracycline inducible (Tet on) lentiviral expression vectors under the control of an adipose-specific promoter were constructed. The lowest basal expression in the absence of doxycycline and most efficient dose-dependent, doxycycline-induced transient overexpression was observed using vectors constructed with a combination of Tetracycline Responsive Element (TRE) and reverse tetracycline-controlled TransActivator advance...

  20. The elusive endogenous adipogenic PPARy agonists: lining up the suspects

    Science.gov (United States)

    Centrally placed in the development of adipocytes is the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma). Ligand-mediated activation of PPARgamma happens early during adipogenesis and is thought to prime adipose conversion. Although several fatty acids and their derivat...

  1. The elusive endogenous adipogenic PPARγ agonists: Lining up the suspects

    DEFF Research Database (Denmark)

    Hallenborg, Philip; Petersen, Rasmus K.; Kouskoumvekaki, Irene;

    2016-01-01

    The nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ) is the key decisive factor controlling the development of adipocytes. Ligand-mediated activation of PPARγ occurs early during adipogenesis and is thought to prime adipose conversion. Although several fatty acids and their d...

  2. Chromium propionate enhances adipogenic differentiation of bovine intramuscular adipocytes

    OpenAIRE

    Rebecca eTokach; Flavio eRibeiro; Ki Yong eChung; Whitney eRounds; Johnson, Bradley J.

    2015-01-01

    In vitro experiments were performed to determine the effects of increasing concentrations of chromium propionate on mRNA and protein abundance of different enzymes and receptors. Intramuscular and subcutaneous preadipocytes and bovine satellite cells were isolated from the longissimus muscle to determine the effect of treatment on glucose transporter type 4 (GLUT4) and peroxisome proliferator-activated receptor γ mRNA and GLUT4 protein abundance. Preadipocyte cultures were treated with diffe...

  3. Chromium Propionate Enhances Adipogenic Differentiation of Bovine Intramuscular Adipocytes

    OpenAIRE

    Tokach, Rebecca J.; Ribeiro, Flavio R. B.; Chung, Ki Yong; Rounds, Whitney; Johnson, Bradley J.

    2015-01-01

    In vitro experiments were performed to determine the effects of increasing concentrations of chromium propionate (CrPro) on mRNA and protein abundance of different enzymes and receptors. Intramuscular (IM) and subcutaneous (SC) preadipocytes and bovine satellite cells were isolated from the longissimus muscle to determine the effect of treatment on glucose transporter type 4 (GLUT4) and peroxisome proliferator-activated receptor γ mRNA and GLUT4 protein abundance. Preadipocyte cultures were t...

  4. Effects of different concentration of insulin-like growth factor-1 on adipogenic differentiation from human umbilical cord mesenchymal stem cells%不同浓度胰岛素样生长因子-1对人脐带间充质干细胞诱导成脂后生长状态的影响

    Institute of Scientific and Technical Information of China (English)

    刘毅; 徐斌; 唐军

    2012-01-01

    Objective To observe the change of optical density of human umbilical cord mes-enchymal stem cells (hUCMSCs) during differentiating into the adipocytes in the condition of insulin-like growth factor-1 (IGF-1) with different concentrations and to elucidate the suitable concentration of IGF-1 in adipocyte induction. Methods hUCMSCs were separated and cultivated in vitro and hUCMSCs were induced to adipocytes. The third passage cells were randomly divided into five groups. The induced culture medium was interfered with different IGF-1 concentration, respectively 40, 60, 80, 100, 120 ng/mL. Then, the 3-(4, 5)-dimethylthiahiazo(-z-yl)-3,5-diphenytetrazoliumromide testing was conducted on the five sample groups to measure the optical density (D). On the 9th day, the samples were stained by Oil red O. Results There was no significant difference among the cells growth in five groups. The difference in D showed no statistical meaning. The lipids were all formed in the five sample groups. The number of lipids in80, 100 and 120 ng/mL groups were obviously more than other two groups (P <0.01). There was no difference among the 80, 100 and 120 ng/mL group. Conclusion Different concentration of IGF-1 has no significant effect on human umbilical cord mesenchymal stem cells. But IGF-1 with high concentration can effectively induce adipogenic differentiation of hUCMSCs and 80 ng/mL is the most proper concentration.%目的 探讨不同浓度胰岛素样生长因子-1 (IGF-1)对人脐带间充质干细胞(hUCMSCs)诱导成脂后生长状态的影响.方法 培养hUCMSCs并传代,将第3代hUCMSCs随机分为5组,成脂肪诱导24h后,分别加入40、60、80、100、120 ng/mL的IGF-1,对5组样本进行四甲基偶氮唑盐检测,测量光密度.于第9天行油红O染色.结果 各组细胞生长趋势一致,光密度值之间的差异无统计学意义.5组细胞均有红色脂滴形成,80、100、120 ng/mL组成脂数量明显多于40和60 ng/mL组(P <0.01); 80、100、120 ng

  5. Regulation Effects of Liuwei Dihuang Pill, Jingui Shenqi Pill, Jiangu Erxian Pill Containing Serums on Adipogenic and Osteogenic Differentiation-related Genes Expressions in the Differentiation Process of Preadipocytes to Osteoblasts%六味地黄丸、金匮肾气丸及健骨二仙丸含药血清对BMSCs成脂、成骨细胞分化相关基因的影响

    Institute of Scientific and Technical Information of China (English)

    程志安; 韩凌; 危建安; 孙静; 段晓栋

    2013-01-01

    preadipocytes was intervened by Liuwei Dihuang Pill (LDP), Jingui Shenqi Pill (JSP), or Jiangu Erxian Pill (JEP)-containing serums (with the concentRation of 10%, on behalf of tonifying Shen yin, tonifying Shen yang, and tonifying Shen essence). Reverse transcription-real time fluorescent quantitative-PCR (RT real time qPCR) was used to detect RUNX2, ALP, BGP, BMP2, BMP4, SPP1, and IGF1 mRNA expressions of osteogenic differentiation-related genes, mRNA expressions of LPL, FABP4, and PPAR7 of adipogenic differentiation-related genes on the 6th, the 12th, and the 18th day. Results As for the osteogenic differentiation-related gene, when compared with the control group, there was no statistical differ- ence in the gene expression level in the experimental groups on the 6th day (2.0 >Ratio >0.5). On the 12th day, the mRNA expressions of IGF1 and Runx2 increased more significantly in the JSP group, with their relative quantification (Ratio) being 2.97 and 1.81 respectively. On the 18th day the IGF1 mRNA expression significantly increased, being the Ratio value of 3.74, 12.60, and 8.35, respectively, in the LDP group, the JSP group, and the JEP group. The SPP1 mRNA expression also significantly increased, with the Ratio value of 2.94, 3.18, and 2.62, respectively, in the LDP group, the JSP group, and the JEP group. As for adipogenic differentiation-related genes, on the 6th day, when compared with the control group, FABP4 mRNA expression significantly decreased in the LDP group and the JSP group (with the Ratio value of 0.47 and 0.40 respectively). The expression levels of other genes were all down-regulated, but not significantly. On the 12th day and 18th day, there was no statistical change in the adipogenic differentiation-related genes expressions (2.0 >Ratio >0.5). Conclusions Up-regulation of osteogen-ic differentiation-related genes expression occurred in later time, while down-regulation of adipogenic differentiation-related genes expression occurred in earlier time after

  6. 大鼠松果体Clock基因和芳烷脘N-乙酰基转移酶基因的昼夜节律性表达及光照影响%Circadian rhythms and light responses of clock gene and arylalkylamine N-acetyltransferase gene expressions in the pineal gland of rats

    Institute of Scientific and Technical Information of China (English)

    王国卿; 杜玉珍; 童建

    2005-01-01

    探讨12 h光照、12 h黑暗交替(12 h-light:12 h-dark cycle,LD)及持续黑暗(constant darkness,DD)光制下松果体Clock基因和芳烷脘N-乙酰基转移酶基因(arylalkylamine N-acetyltransferase gene,NAT)是否存在昼夜节律性表达及其光反应变化.Sprague-Dawley大鼠在LD和DD光制下分别被饲养4周(n=36)和8周(n=36)后,在一昼夜内每隔4 h采集一组松果体组织(n=6),提取总RNA,用竞争性定量RT-PCR测定不同昼夜时点样品中Clock及NAT基因的mRNA相对表达量,通过余弦法和ClockLab软件获取节律参数,并经振幅检验是否存在昼夜节律.结果如下:(1)在DD或LD光制下,松果体Clock和NAT基因mRNA的表达均呈现夜高昼低的节律性振荡(P<0.05).(2)与DD光制下比较,LD光制下松果体Clock和NAT基因的表达振幅及峰值相的mRNA水平均降低(P<0.05).(3)在DD或LD光制下,Clock和NAT基因之间显示相似的节律性表达(P>0.05).结果表明,Clock和NAT基因在松果体中存在同步的内源性昼夜节律表达,光照作用可使其表达下调.

  7. 杜氏盐藻甘油醛-3-磷酸脱氢酶基因启动子驱动氯霉素乙酰转移酶基因的表达及其活性检测%Expression and activity detection of chloramphenicol acetyltransferase gene driven by the glyceraldehyde-3-phosphate dehydrogenase gene of Dunaliella salina

    Institute of Scientific and Technical Information of China (English)

    张小毅; 刘巨源; 邱乐乐; 贾岩龙

    2012-01-01

    目的 为建立稳定高效的盐藻生物反应器寻找合适的内源性启动子驱动表达外源基因.方法 克隆鉴定了盐藻甘油醛-3-磷酸脱氢酶(GAPDH)基因5 ′上游区序列并成功构建由盐藻GAPDH基因启动子驱动的氯霉素乙酰转移酶(CAT)基因表达载体pUC-Gcat.利用构建的表达载体电击转化盐藻并在含有氯霉素的培养基中筛选转化藻株.随机挑选稳定转化的盐藻藻株进行CAT酶联免疫吸附测定分析.结果 获得3株稳定转化的盐藻藻株.聚合酶链式反应鉴定和CAT酶联免疫吸附测定分析结果表明,CAT基因已整合到了转化的盐藻基因组中.结论 本研究所克隆的内源性盐藻GAPDH基因启动子能够驱动CAT基因在盐藻中表达.%Objective To explore expression of foreign gene driven by a strong endogenous promoter in order to construct stable and high-performance bioreactors in Dunaliella salina. Methods In the present study, the upstream sequence of glyceraldehyde phosphate dehydrogenase of Dunaliella salina was cloned and identificated. Using electroporation, the alga was transformed with a plasmid pUC-Ccat containing giyceraldehyde-3-phosphate dehydrogenase ( GAPDH) gene promoter of Du-naliella salina and chloramphenicol acetyltransferase ( CAT) gene as a seletable gene. Using the expression vector, the Dunaliella salina cell was translated and the transformational strain was screened in nutrient medium containing chloramphenicol. The stable transformational strain was selected randomly to undertake CAT enzyme linked immunosorbent assay (ELISA). Results Three stable transformational strain were obtained. The results of polymerase chain reaction and CAT ELISA indicated that the CAT gene had been transferred to the alga. Conclusion The results of this paper suggest that the GAPDH gene promoter can work for genetic transformation of Dunaliella salina.

  8. Insight into cofactor recognition in arylamine N-acetyltransferase enzymes

    DEFF Research Database (Denmark)

    Xu, Ximing; Li de la Sierra-Gallay, Inés; Kubiak, Xavier Jean Philippe;

    2015-01-01

    for Bacillus anthracis NAT1 and Homo sapiens NAT2. Therefore, in contrast to previous data, this study shows that different orthologous NATs can bind their cofactors in a similar way, suggesting that the mode of binding CoA in this family of enzymes is less diverse than previously thought. Moreover...

  9. Coactivator p100 protein enhances histone acetyltransferase activity of CBP

    Institute of Scientific and Technical Information of China (English)

    JIE YANG; HONG BAI; Li JIE DONG; JIE SHAO; OLLI SILVENNOINEN; ZHI YAO

    2006-01-01

    Human p100 protein consists of four repeated domains of staphylococcal nuclease (SN)-like domain, as well as a tudor (TD) domain thereafter. We have previously shown that the SN-like domain of p100 interacted with STAT6 and the large subunit of RNA pol Ⅱ, resulting in the enhancement of STAT6-mediated gene transcriptional activation. Here, we show that SN-like domain also interacted with CREB binding protein (CBP) and directly enhanced the acetyl transferase activity of CBP on histone. On the other hand, overexpression of CBP alone had no ability to significantly increase STAT6-dependent transcriptional activation, however, together with p100 protein, sufficiently enhanced the activation of transcription which was in line with the previous result that p100 protein bridged STAT6 with CBP.

  10. Targeting cancer using KAT inhibitors to mimic lethal knockouts

    Science.gov (United States)

    Brown, James A.L.; Bourke, Emer; Eriksson, Leif A.; Kerin, Michael J.

    2016-01-01

    Two opposing enzyme classes regulate fundamental elements of genome maintenance, gene regulation and metabolism, either through addition of an acetyl moiety by histone acetyltransferases (HATs) or its removal by histone de-acetyltransferases (HDAC), and are exciting targets for drug development. Importantly, dysfunctional acetylation has been implicated in numerous diseases, including cancer. Within the HAT superfamily the MYST family holds particular interest, as its members are directly involved in the DNA damage response and repair pathways and crucially, several members have been shown to be down-regulated in common cancers (such as breast and prostate). In the present study we focus on the development of lysine (K) acetyltransferase inhibitors (KATi) targeting the MYST family member Tip60 (Kat5), an essential protein, designed or discovered through screening libraries. Importantly, Tip60 has been demonstrated to be significantly down-regulated in many cancers which urgently require new treatment options. We highlight current and future efforts employing these KATi as cancer treatments and their ability to synergize and enhance current cancer treatments. We investigate the different methods of KATi production or discovery, their mechanisms and their validation models. Importantly, the utility of KATi is based on a key concept: using KATi to abrogate the activity of an already down-regulated essential protein (effectively creating a lethal knockout) provides another innovative mechanism for targeting cancer cells, while significantly minimizing any off-target effects to normal cells. This approach, combined with the rapidly developing interest in KATi, suggests that KATi have a bright future for providing truly personalized therapies. PMID:27528742

  11. Relationship between polymorphism of arylamine N-acetyltransferase 2 and genetic susceptibility to hair dye dermatitis%N-乙酰基转移酶2基因多态性与染发皮炎易感性关系

    Institute of Scientific and Technical Information of China (English)

    杨秋艳; 徐宏俊; 刘原君; 姚卫锋; 刘全忠

    2011-01-01

    目的 探讨N-乙酰基转移酶2(NAT2)基因多态性与中国人染发皮炎遗传易感性的关系.方法 应用聚合酶链反应(PCR)及限制性片段长度多态性(RFLP)技术检测和分析天津地区60例染发皮炎患者及73例正常对照者的NAT2野生型等位基因(NAT2*4)和3个常见突变位点(NAT2*5A,NAT2*6B和NAT2*7A)的基因多态性,比较NAT2各等位基因及基因型频率在染发皮炎组与对照组间分布差异.结果 NAT2等位基因NAT2*4,NAT2*5A,NAT2*6B和NAT2*7A在染发皮炎组中的分布频率分别是52.5%,5.0%,26.7%,15.8%,在对照组中为55.5%,3.4%,27.4%,13.7%,两组相比差异均无统计学意义(P>0.05);快型、中间型、慢型基因型在染发皮炎组中频率分别是26.7%,51.7%,21.7%,在对照组中为30.1%,50.7%,19.2%,与对照组相比差异无统计学意义(P>0.05).结论 NAT2基因多态性与中国汉族人染发皮炎遗传易感性无关.%Objective To investigate the relationship between polymorphism of arylamine N-acetyltransferase 2 (NAT2) and hair dye dermatitis in a Chinese population. Methods Polymorphism chain-restriction fragment length polymorphism (PCR-RFLP) was used and the wild-type allele (NAT2 * 4) and three mutant alleles (NAT2 * 5A, 6B and 7A) were determined in 60 patients with hair dye dermatitis and 73 age-matched control subjects in Tianjin region. Results In hair dye dermatitis cases, the frequency of NAT2 * 4, NAT2 * 5A, NAT2 * 6B, NAT2 * 7A was 52. 5 % , 5. 0 % ,26.7 % and 15. 8 %, respectively, and no statistically significant difference of the frequencies was found between the hair dye dermatitis patients and controls (P>0. 05). The frequency of rapid genotype, intermediate genotype and slow genotype was 26. 7 % , 51. 7 % and 21. 7 % in hair dye dermatitis cases, 30. 1 %, 50. 7 % and 19. 2 % in control subjects, respectively, and no statistically significant difference of the frequencies between the two groups (P>0. 05). Conclusions Our study suggests that there might be

  12. 术后睡眠剥夺对老龄大鼠海马胆碱乙酰转移酶表达的影响%Effects of postoperative sleep deprivation on expression of choline acetyltransferase in hippocampi of aged rats

    Institute of Scientific and Technical Information of China (English)

    王威; 丁明; 张迅; 宗波; 张蕊

    2015-01-01

    目的 探讨术后睡眠剥夺对老龄大鼠海马胆碱乙酰转移酶(ChAT)表达的影响.方法 健康雄性Wistar大鼠48只,体重500~ 600 g,20月龄,采用随机数字表法将其分为4组(n=12):对照组(C组)、手术组(O组)、睡眠剥夺组(S组)和术后睡眠剥夺组(OS组).OS组于脾切除术清醒后,S组于相应时点采用小平台水环境法制备睡眠剥夺模型,剥夺睡眠24 h.于术后24 h时行Morris水迷宫实验.水迷宫测试完成后,行海马CA1区ChAT阳性细胞计数.结果 与C组比较,O组和OS组术后逃避潜伏期延长,原平台象限停留时间缩短,穿越原平台次数减少,海马CA1区ChAT阳性细胞数减少(P<0.05),S组上述指标差异无统计学意义(P>0.05);与O组比较,OS组术后逃避潜伏期延长,原平台象限停留时间缩短,穿越原平台次数减少(P<0.05),海马CA1区ChAT阳性细胞数差异无统计学意义,S组上述指标差异无统计学意义(P>0.05);与S组比较,OS组术后逃避潜伏期延长,原平台象限停留时间缩短,穿越原平台次数减少,海马CA1区ChAT阳性细胞数减少(P<0.05).结论 术后睡眠剥夺诱发老龄大鼠术后认知功能减退的机制与海马ChAT的表达无关.%Objective To investigate the effects of postoperative sleep deprivation on the expression of choline acetyltransferase (ChAT) in hippocampi of aged rats.Methods Forty-eight male Wistar rats,aged 20 months,weighing 500-600 g,were randomly divided into 4 groups (n =12 each) using a random number table:control group (group C) ; operation group (group O) ; sleep deprivation group (group S) ; postoperative sleep deprivation group (group OS).Sleep deprivation was induced in the rats by housing them on small platforms over water.They fell into the water if they lost muscle tone.All the rats had free access to food and water.In group OS,splenectomy was performed,and all the rats underwent 24 h sleep deprivation after the rats were awake.All the rats underwent 24 h

  13. The interaction between environmental risk factors and genetic polymorphisms of N-acetyltransferase-2 and the risk of female breast cancer%环境危险因素和NAT2基因多态性的交互作用与女性乳腺癌的关系

    Institute of Scientific and Technical Information of China (English)

    李君; 蒋守芳; 陈海燕; 刘坤; 袁聚祥; 牛凤玲; 张国志

    2013-01-01

    OBJECTIVE: To explore environmental factors and the association of NAT2 genetic polymorphism and female breast cancer,and their interactions. METHODS:A case-control study was adopted to collect information in 140 female primary breast cancer diagnosed by pathology and treated in major hospitals of Tangshan city. The 140 controls were selected from the female patients without tumor from the same hospitals at the same time. Each subject was investigated by an unified questionnaire,which mainly included eating habits and ways of life,environment and occupational exposure,etc. DNA was extracted by salting out method,and NAT2 genotype were detected by polymerase chain reaction-restriction fragment polymorphism (PCR-RFLP). SPSS 13.0 were adopted to statistically analyze the data. RESULTS:Environmental risk factors of female breast cancer were environmental PAHs pollution of residence,occupational exposure to PAHs,occupational use of pesticide exceeding 10 years,indoor insecticide use over 5 years,passive smoking wore than 10 years. While more intake of beans,fumes exhaust equipment used in cooking were all protective factors. The frequencies of rapid and slow speed acetylation phenotypes were 55.0%,45.0% in case group,and 77.9%,22.1% in control group,respectively. The difference was statistically significant (P<0.05). There were interactions between passive smoking exceeding 10 years,as well as occupational PAHs exposure and NAT2 slow speed acetylation phenotype. The interaction value were 3.39 and 1.70,respectively (P<0.05). CONCLUSION: There were interactions between passive smoking or occupational exposure and carrying slow speed acetylation phenotype,which would increase the risk of breast cancer.%目的:探讨环境危险因素、N-乙酰基转移酶-2(N-acetyltransferase-2,NAT2)基因多态性以及二者的交互作用与女性乳腺癌的关系.方法:采用病例对照研究,选择经病理确诊的原发

  14. 穹窿海马伞切断大鼠不同脑区胆碱乙酰化转移酶表达的变化%Expressive variety of choline acetyltransferase in different cerebral regions of rats with fimbria/fornix transection

    Institute of Scientific and Technical Information of China (English)

    郭宗君; 金丽英; 银建军

    2006-01-01

    BACKGROUND: The choline acetyltransferase (CHAT) is the key synthetic enzyme for acetylcholine, and is the important symbol of the functional activity of the cholinergic system. There was a relationship of the cholinergic neurons damage with the pathogenesis of Alzheimer disease (AD) and the mild cognitive impairment (MCI). Whether or not the fimbria/fornix transection may affect the expressive variety of ChAT in different cerebral regions of rats (cortex, hippocammpi CA1, amygdala, Meynert nucleus) is very important for the recognition of the pathogenesis of AD and MCI and the establishment of experimental animal model of AD.OBJECTIVE: To observe the expressive variety of ChAT in different cerebral regions of rats with fimbria/fornix transection and discuss exploratorily the methods of simulative experimental AD.DESIGN: A randomized and control study.SETTING: Institute of Cerebrovascular Disease, Affiliated Hospital of the Qingdao University Medical College and the Department of Neurology, No. 1People' s Hospital of Jining.MATERIALS: The experiment was completed in the Institute of Cerebrovascular Disease, Affiliated Hospital of the Qingdao University Medical College from March to December 2003. Totally 14 adult healthy female Wistar rats aged 5 months were randomly divided into model group and control group with 7 in each group.METHODS: ① The bilateral fimbria-fornix of brain in model group were transected on the stereotaxic apparatus to set animal model. After opening the skull, at the coordinates, along the bregma posterior 2.2 mm-2.5 mm and lateral 1.0 mm according to the atlas of Paxinos and Watson, and the dorsal fornix, the anterior part of hippocampus and the fimbria were cut off with a double blade under visual inspection. Rats in the control group were not performed with fimbria/fornix transection, and the other procedures were completed as those in the model group. ② On the 28 day after the surgery, all rats were killed under anesthesia to take out

  15. 龙葵碱对HepG2细胞NAT1酶活性及动力学影响的研究%Study on the Effect of Solanine on N-acetyltransferase 1 Activity in HepG2

    Institute of Scientific and Technical Information of China (English)

    高世勇; 苏怡君; 季宇彬

    2011-01-01

    目的 探讨龙葵碱诱导HepG2细胞凋亡的芳香胺Ⅳ-乙酰化转移酶(NAT)1的影响.方法 采用高效液相色谱法(HPLC),以对氨基笨甲酸(PABA)为底物,以PABA被NAT1乙酰化为乙酰对氨基苯甲酸(Ac-PABA)的量反应NAT1酶的活性.观察不同浓度、不同时间龙葵碱对完整HepG2细胞NAT1酶活性的影响;龙葵碱对HepG2细胞细胞质中NAT1酶活性的影响;通过改变底物PABA浓度,采用双倒数作图法,以底物PABA浓度的倒数(1/S)对NAT1反应速率的倒数(1/V)作直线,得出回归方程,计算K和.结果 在NAT1酶活性测定中,龙葵碱能显著降低HepG2完整细胞NAT1的活性;龙葵碱能够降低HepG2细胞质内NAT1的活性;随着作用时间的增加Ac-PABA生成的量逐渐增加,但在相同作用时间段龙葵碱能显著降低Ac-PABA生成的量.动力学研究表明,以PABA为底物,对于HepG2完整细胞,阴性对照组的K和V分别为(1.04 x 10±8.36×10-5)mmol·L、(1.64×10±9.57×10)nmol·10cells,龙葵碱组的K和K分别为(1.06×10±6.97×10)mmol·L和(1.48×10±4.28×10)nmol·10cells·h.对于HepG2细胞质,阴性对照组的K和V分别为(3.32×10±2.35×10)mmol·L、(2.60×10±6.79×10)nmol·h·mg pro,龙葵碱组的K和K分别为(3.35×10±1.66×10)mmol·L和(2.22x10±8.12×10)nmol·h·mg(Pro),经统计学处理表明,对于HepG2完整细胞和细胞质,阴性对照组和龙葵碱组的K没有差异,而V差异显著结论 龙葵碱是HepG2细胞NAT1酶的非竞争性抑制剂.龙葵碱通过作用于NAT1与PABA结合位点以外的其他位点抑制NAT1酶的活性而诱导HepG2细胞凋亡.%OBJECTIVE To explore the relationship between N-acetyltransferase 1 activity and apoptosis inducing by solanine in HepG2 cell. METHODS The speed of PABA acetylation reaction mediated by NAT1 was teken as the indicator of the activity of NAT1 in intact HepG2 cells and their cytoplasm. HPLC was employed to determine the concentration of AC-PABA, the effects of different concentrations of

  16. Association between Genetic Polymorphisms of N-acetyltransferase 2, Environmental Factors and Female Breast Cancer%N-乙酰基转移酶-2基因多态性和环境因素与女性乳腺癌的关系

    Institute of Scientific and Technical Information of China (English)

    陈海燕; 李君; 蒋守芳; 刘坤; 赵刚; 牛凤玲; 张国志

    2012-01-01

    目的 分析N-乙酰基转移酶-2( NAT2)基因多态性和环境因素与女性乳腺癌的关系.方法 采用以医院为基础的1:1配对的病例-对照研究,收集唐山市原发性乳腺癌新发女性患者48例与相应非肿瘤患者48例.以问卷调查收集各研究对象的饮食习惯和生活方式、生理生育、环境暴露和职业接触、既往病史、心理等信息.采用聚合酶链反应-限制性片段多态性(PCR-RFLP)技术检测NAT2的野生型等位基因WT、突变型等位基因M1、M2和M3突变频率,分析NAT2基因多态性和环境危险因素与女性乳腺癌的关系.结果 被动吸烟大于或等于10年(OR=3.957,95%CI:1.589~10.002)、居住地环境污染(OR=33.571,95%CI:4.270~263.967)、职业接触(OR=9.400,95%CI:1.127~78.405)、烹调时使用排油设备(OR=0.177,95%CI:0.060~0.529)、农药的使用(OR=28.200,95%CI:3.576~222.389)等是乳腺癌的环境危险因素.携带M2、M3等位基因可能是乳腺癌的危险因素,OR值分别为2.563(95%CI:1.155~5.707)和2.083(95%CI:1.068~4.062),而M1等位基因频率在病例组与对照组的分布差异无统计学意义(x2=0.447,P>0.05).病例组与对照组突变杂合子基因型(WT/Mx)分布频率差异无统计学意义(x2=0.021,P>0.05),而两组间突变纯合子(Mx/Mx)分布频率差异有统计学意义(OR=3.545,95%CI:1.141~11.015).慢乙酰化表型者患乳腺癌的风险是快乙酰化表型者的3.364倍(x2=7.599,P<0.05).分层分析发现NAT2慢乙酰化表型与被动吸烟大于或等于10年存在交互作用(OR=9.917,95%CI:1.597~61.597).结论 NAT2基因多态性和部分环境危险因素与乳腺癌发病存在统计学关联.%Objective To explore the association between N -acetyltransferase 2 (NAT2) genetic polymorphisms, environmental factors and female breast cancer in Tangshan area, Hebei, China. Methods A 1:1 matched case-control study was conducted in which 48 primary breast cancer cases and 48

  17. Anti-adipogenic activity of an olive seed extract in mouse fibroblasts.

    Science.gov (United States)

    Veciana-Galindo, Carmen; Cortés-Castell, Ernesto; Torró-Montell, Luis; Palazón-Bru, Antonio; Sirvent-Segura, Elia; Rizo-Baeza, María M; Gil-Guillén, Vicente F

    2015-06-01

    La administración de diferentes polifenoles protege contra el incremento de peso y la acumulación de grasa. Objetivo: comprobar la actividad anti-adipogénica de un extracto polifenólico de huesos de aceituna, utilizando la diferenciación a adipocitos de la línea celular 3T3-L1 de fibroblastos de ratón. Material y métodos: se cultivan y diferencian las células (6.000 células/pocillo) en presencia del extracto de huesos de aceitunas a 10 y 50 mg/l de polifenoles, concentraciones bioseguras, y sin extracto como control. A los 5-7 días se forman los adipocitos maduros. Se cuantifican los cúmulos de grasa formados mediante tinción con Oil- Red y medida de la absorbancia a 490 nm y la expresión de los genes de leptina y PPARg, relacionándolos con los valores en los cultivos antes y después de diferenciarse a adipocitos. Resultados: las muestras control, sin extracto, se consideran el 100% de acumulación de grasas. En contraste, la adición de 50 mg/l de extracto de polifenoles de huesos de aceituna muestra un cúmulo de grasa de alrededor del 50%, semejante a las células no diferenciadas. Con 10 mg/l de extracto no se muestra efecto. Se confirma la actividad antiadipogénica, observándose disminución en la expresión de los genes PPARg y de leptina en la diferenciación a adipocitos en presencia del extracto a 50 mg/l. En conclusión, la formación de los cuerpos grasos característicos de la adipogénesis queda inhibida previa adición de 50 mg/l de polifenoles de extracto de huesos de aceituna, así como la expresión de los genes adipogénicos PPARg y de leptina.

  18. Enhanced adipogenic differentiation of bovine bone marrow-derived mesenchymal stem cells

    Science.gov (United States)

    Until now, the isolation and characterization of bovine bone marrow-derived mesenchymal stem cells (bBM-MSCs) have not been established, which prompted us to optimize the differentiation protocol for bBM-MSCs. In this study, bBM-MSCs were freshly isolated from three 6-month-old cattle and used for p...

  19. Adipose Stromal Cells Contain Phenotypically Distinct Adipogenic Progenitors Derived from Neural Crest

    OpenAIRE

    Yoshihiro Sowa; Tetsuya Imura; Toshiaki Numajiri; Kosuke Takeda; Yo Mabuchi; Yumi Matsuzaki; Kenichi Nishino

    2013-01-01

    Recent studies have shown that adipose-derived stromal/stem cells (ASCs) contain phenotypically and functionally heterogeneous subpopulations of cells, but their developmental origin and their relative differentiation potential remain elusive. In the present study, we aimed at investigating how and to what extent the neural crest contributes to ASCs using Cre-loxP-mediated fate mapping. ASCs harvested from subcutaneous fat depots of either adult P0-Cre/or Wnt1-Cre/Floxed-reporter mice contain...

  20. New phenolic compounds with anti-adipogenic activity from the aerial parts of Pulsatilla koreana.

    Science.gov (United States)

    Liu, Qing; Ahn, Jong Hoon; Kim, Seon Beom; Hwang, Bang Yeon; Lee, Mi Kyeong

    2012-11-01

    Three new phenolic compounds, pulsatillosides A (1), B (2), and C (3), were isolated from the aerial parts of Pulsatilla koreana, together with two known flavonoid glycosides, trans-tiliroside (4) and kaempferol-3-O-β-glycoside (5). The structures of the isolated compounds were determined on the basis of spectroscopic analysis including 1D, 2D NMR and HR-MS. Among the isolated compounds, compounds 1-3 significantly inhibited adipocyte differentiation as measured by fat accumulation in 3 T3-L1 cells using Oil Red O staining.

  1. Differential adipogenic and inflammatory properties of small adipocytes in Zucker Obese and Lean rats

    OpenAIRE

    Liu, Alice; Sonmez, Alper; Yee, Gail; Bazuine, Merlijn; Arroyo, Matilde; Sherman, Arthur; McLaughlin, Tracey; Reaven, Gerald; Cushman, Samuel; Tsao, Philip

    2010-01-01

    We recently reported that a preponderance of small adipose cells, decreased expression of cell differentiation markers, and enhanced inflammatory activity in human subcutaneous whole adipose tissue were associated with insulin resistance. To test the hypothesis that small adipocytes exhibited these differential properties, we characterized small adipocytes from epididymal adipose tissue of Zucker Obese (ZO) and Lean (ZL) rats. Rat epididymal fat pads were removed and adipocytes isolated by co...

  2. Hybrid Adipogenic Implants from Adipose Stem Cells for Soft Tissue Reconstruction In Vivo

    OpenAIRE

    MOIOLI, EDUARDO K.; Chen, Mo; Yang, Rujing; Shah, Bhranti; Wu, June; Mao, Jeremy J

    2010-01-01

    A critical barrier in tissue regeneration is scale-up. Bioengineered adipose tissue implants have been limited to ∼10 mm in diameter. Here, we devised a 40-mm hybrid implant with a cellular layer encapsulating an acellular core. Human adipose-derived stem cells (ASCs) were seeded in alginate. Poly(ethylene)glycol-diacrylate (PEGDA) was photopolymerized into 40-mm-diameter dome-shaped gel. Alginate-ASC suspension was painted onto PEGDA surface. Cultivation of hybrid constructs ex vivo in adipo...

  3. Harnessing the beneficial properties of adipogenic microbes for improving human health

    DEFF Research Database (Denmark)

    Dhurandhar, N V; Geurts, L; Atkinson, R L;

    2013-01-01

    protection from obesity-induced metabolic comorbidities. To this end, the 10th Stock conference examined new approaches to improve metabolic comorbidities independent of weight loss. In particular, human adenovirus 36 (Ad36) and specific gut microbes were examined for their potential to influence lipid...... and glucose homeostasis in animals and humans. While these microbes possess some undesirable properties, research has identified attributes of adenovirus Ad36 and gut microbes that may be selectively harnessed to improve metabolic profile without the obligatory weight loss. Furthermore, identifying the host......Obesity is associated with numerous metabolic comorbidities. Weight loss is an effective measure for alleviating many of these metabolic abnormalities. However, considering the limited success of most medical weight-management approaches in producing a sustained weight loss, approaches that improve...

  4. Myristic Acid (MA) Promotes Adipogenic Gene Expression and the Differentiation of Porcine Intramuscular Adipocyte Precursor Cells

    Institute of Scientific and Technical Information of China (English)

    LU Nai-sheng; ZHANG Yong-liang; JIANG Qing-yan; SHU Gang; XIE Qiu-ping; ZHU Xiao-tong; GAO Ping; ZHOU Gui-xuan; WANG Song-bo; WANG Li-na; XI Qian-yun

    2014-01-01

    Intramuscular fat (IMF) content is considered to be a key factor that affects the marbling, tenderness, juiciness and lfavor of pork. To investigate the effects of myristic acid (MA) on the differentiation of porcine intramuscular adipocytes, cells were isolated from longissimus dorsi muscle (LDM) and treated with 0, 10, 50 or 100μmol L-1 MA. The results showed that MA signiifcantly promotes the differentiation of intramuscular adipocytes in a dose-dependent manner. MA also led to a parallel increase in the expression of peroxisome proliferator activated receptor-γ(PPARγ) and adipose-related genes, such as glucose transporter 1 (GLUT1), lipoprotein lipase (LPL), adipocyte fatty acid binding protein 4 (FABP4/aP2), fatty acid translocase (FAT), acetyl-CoA carboxylaseα(ACCα), adipose triglyceride lipase (ATGL) and fatty acid synthase (FASN). However, no signiifcant effects of MA were observed on the expression of CAAT enhancer binding protein-α(C/EBPα) or hormone sensitive lipase (HSL). The expression of pyruvate dehydrogenase kinase 4 (PDK4) was increased by MA during the early stages of differentiation (day 1-3). In addition, MA also increased the absolute content of C14 (P<0.001) and saturated fatty acids (SFA) (P<0.05) to varying degrees, but no effects were observed on other fatty acids. These results suggest that MA might be able to enhance the IMF content of pork and increase the accumulation of myristic and myristoleic acid in muscle, which might have beneifcial implications for human health.

  5. Power-Frequency Magnetic Field Inhibits Adipogenic Differentiation in Human ADSC

    Directory of Open Access Journals (Sweden)

    María Antonia Martínez

    2015-12-01

    Full Text Available Background/Aims: Semicircular lipoatrophy (SL is an idiopathic condition characterized by atrophy of subcutaneous fatty tissue. Although several studies have suggested a possible association between SL and occupational exposure to power frequency magnetic fields (MF, no mechanism has been proposed so far that explains an influence of these fields on adipogenesis. Methods: The study investigates the effects of a 50 Hz, 100 µT MF on the adipogenesis of stem cells isolated from human adipose tissue (ADSC. Cells were plated in Petri dishes and either exposed intermittently to the field for 42 hours or sham-exposed. Results: Field exposure significantly reduced lipid accumulation within the cells, revealed in Oil Red O stained samples by spectrophotometry and colorimetry. Early cell passages were particularly sensitive to the effect: 30.40 ± 5.77% and 47.96 ± 12.47% below controls in the spectrophotometric and colorimetric assays, respectively. Such antiadipogenic effect was accompanied by significant changes in the expression of key effectors/regulators of early adipogenesis: PPARγ, p-ERK1/2 and Sox9, indicating that at least the ERK/PPARγ signaling pathway could be involved in the effect. Conclusions: These results constitute an experimental support to the hypothesis that power frequency MF can be one of the factors involved in the etiology of SL.

  6. Transient ciliogenesis involving Bardet-Biedl syndrome proteins is a fundamental characteristic of adipogenic differentiation.

    Science.gov (United States)

    Marion, Vincent; Stoetzel, Corinne; Schlicht, Dominique; Messaddeq, Nadia; Koch, Michael; Flori, Elisabeth; Danse, Jean Marc; Mandel, Jean-Louis; Dollfus, Hélène

    2009-02-10

    Bardet-Biedl syndrome (BBS) is an inherited ciliopathy generally associated with severe obesity, but the underlying mechanism remains hypothetical and is generally proposed to be of neuroendocrine origin. In this study, we show that while the proliferating preadipocytes or mature adipocytes are nonciliated in culture, a typical primary cilium is present in differentiating preadipocytes. This transient cilium carries receptors for Wnt and Hedgehog pathways, linking this organelle to previously described regulatory pathways of adipogenesis. We also show that the BBS10 and BBS12 proteins are located within the basal body of this primary cilium and inhibition of their expression impairs ciliogenesis, activates the glycogen synthase kinase 3 pathway, and induces peroxisome proliferator-activated receptor nuclear accumulation, hence favoring adipogenesis. Moreover, adipocytes derived from BBS-patients' dermal fibroblasts in culture exhibit higher propensity for fat accumulation when compared to controls. This strongly suggests that a peripheral primary dysfunction of adipogenesis participates to the pathogenesis of obesity in BBS. PMID:19190184

  7. Adipose stromal cells contain phenotypically distinct adipogenic progenitors derived from neural crest.

    Directory of Open Access Journals (Sweden)

    Yoshihiro Sowa

    Full Text Available Recent studies have shown that adipose-derived stromal/stem cells (ASCs contain phenotypically and functionally heterogeneous subpopulations of cells, but their developmental origin and their relative differentiation potential remain elusive. In the present study, we aimed at investigating how and to what extent the neural crest contributes to ASCs using Cre-loxP-mediated fate mapping. ASCs harvested from subcutaneous fat depots of either adult P0-Cre/or Wnt1-Cre/Floxed-reporter mice contained a few neural crest-derived ASCs (NCDASCs. This subpopulation of cells was successfully expanded in vitro under standard culture conditions and their growth rate was comparable to non-neural crest derivatives. Although NCDASCs were positive for several mesenchymal stem cell markers as non-neural crest derivatives, they exhibited a unique bipolar or multipolar morphology with higher expression of markers for both neural crest progenitors (p75NTR, Nestin, and Sox2 and preadipocytes (CD24, CD34, S100, Pref-1, GATA2, and C/EBP-delta. NCDASCs were able to differentiate into adipocytes with high efficiency but their osteogenic and chondrogenic potential was markedly attenuated, indicating their commitment to adipogenesis. In vivo, a very small proportion of adipocytes were originated from the neural crest. In addition, p75NTR-positive neural crest-derived cells were identified along the vessels within the subcutaneous adipose tissue, but they were negative for mural and endothelial markers. These results demonstrate that ASCs contain neural crest-derived adipocyte-restricted progenitors whose phenotype is distinct from that of non-neural crest derivatives.

  8. α/β-hydrolase domain containing protein 15 (ABHD15--an adipogenic protein protecting from apoptosis.

    Directory of Open Access Journals (Sweden)

    Evelyn Walenta

    Full Text Available Our knowledge about adipocyte metabolism and development is steadily growing, yet many players are still undefined. Here, we show that α/β-hydrolase domain containing protein 15 (Abhd15 is a direct and functional target gene of peroxisome proliferator-activated receptor gamma (PPARγ, the master regulator of adipogenesis. In line, Abhd15 is mainly expressed in brown and white adipose tissue and strongly upregulated during adipogenesis in various murine and human cell lines. Stable knockdown of Abhd15 in 3T3-L1 cells evokes a striking differentiation defect, as evidenced by low lipid accumulation and decreased expression of adipocyte marker genes. In preconfluent cells, knockdown of Abhd15 leads to impaired proliferation, which is caused by apoptosis, as we see an increased SubG1 peak, caspase 3/7 activity, and BAX protein expression as well as a reduction in anti-apoptotic BCL-2 protein. Furthermore, apoptosis-inducing amounts of palmitic acid evoke a massive increase of Abhd15 expression, proposing an apoptosis-protecting role for ABHD15. On the other hand, in mature adipocytes physiological (i.e. non-apoptotic concentrations of palmitic acid down-regulate Abhd15 expression. Accordingly, we found that the expression of Abhd15 in adipose tissue is reduced in physiological situations with high free fatty acid levels, like high-fat diet, fasting, and aging as well as in genetically obese mice. Collectively, our results position ABHD15 as an essential component in the development of adipocytes as well as in apoptosis, thereby connecting two substantial factors in the regulation of adipocyte number and size. Together with its intricate regulation by free fatty acids, ABHD15 might be an intriguing new target in obesity and diabetes research.

  9. Anti-adipogenic effect of mulberry leaf ethanol extract in 3T3-L1 adipocytes

    OpenAIRE

    Yang, Soo Jin; Park, Na-Young; LIM, YUNSOOK

    2014-01-01

    BACKGROUND/OBJECTIVES Adipogenesis is part of the cell differentiation process in which undifferentiated fibroblasts (pre-adipocytes) become mature adipocytes with the accumulation of lipid droplets and subsequent cell morphological changes. Several transcription factors and food components have been suggested to be involved in adipogenesis. The aim of this study was to determine whether mulberry leaf ethanol extract (MLEE) affects adipogenesis in 3T3-L1 adipocytes. MATERIALS/METHODS The 3T3-...

  10. Identification of an Adipogenic Niche for Adipose Tissue Remodeling and Restoration

    OpenAIRE

    Lee, Yun-Hee; Petkova, Anelia P.; Granneman, James G.

    2013-01-01

    The regulatory events guiding progenitor activation and differentiation in adult white adipose tissue are largely unknown. We report that induction of brown adipogenesis by β3-adrenergic receptor (ADRB3) activation involves the death of white adipocytes and their removal by M2-polarized macrophages. Recruited macrophages express high levels of osteopontin (OPN), which attracts a subpopulation of PDGFRα+ progenitors expressing CD44, a receptor for OPN. Preadipocyte proliferation is highly targ...

  11. Identification of an adipogenic niche for adipose tissue remodeling and restoration.

    Science.gov (United States)

    Lee, Yun-Hee; Petkova, Anelia P; Granneman, James G

    2013-09-01

    The regulatory events guiding progenitor activation and differentiation in adult white adipose tissue are largely unknown. We report that induction of brown adipogenesis by β3-adrenergic receptor (ADRB3) activation involves the death of white adipocytes and their removal by M2-polarized macrophages. Recruited macrophages express high levels of osteopontin (OPN), which attracts a subpopulation of PDGFRα+ progenitors expressing CD44, a receptor for OPN. Preadipocyte proliferation is highly targeted to sites of adipocyte clearance and occurs almost exclusively in the PDGFRα+ CD44+ subpopulation. Knockout of OPN prevents formation of crown-like structures by ADRB3 activation and the recruitment, proliferation, and differentiation of preadipocytes. The recruitment and differentiation of PDGFRα+ progenitors are also observed following physical injury, during matrix-induced neogenesis, and in response to high-fat feeding. Each of these conditions recruits macrophages having a unique polarization signature, which may explain the timing of progenitor activation and the fate of these cells in vivo. PMID:24011071

  12. Visualization and quantification of APP intracellular domain-mediated nuclear signaling by bimolecular fluorescence complementation.

    Directory of Open Access Journals (Sweden)

    Florian Riese

    Full Text Available BACKGROUND: The amyloid precursor protein (APP intracellular domain (AICD is released from full-length APP upon sequential cleavage by either α- or β-secretase followed by γ-secretase. Together with the adaptor protein Fe65 and the histone acetyltransferase Tip60, AICD forms nuclear multiprotein complexes (AFT complexes that function in transcriptional regulation. OBJECTIVE: To develop a medium-throughput machine-based assay for visualization and quantification of AFT complex formation in cultured cells. METHODS: We used cotransfection of bimolecular fluorescence complementation (BiFC fusion constructs of APP and Tip60 for analysis of subcellular localization by confocal microscopy and quantification by flow cytometry (FC. RESULTS: Our novel BiFC-constructs show a nuclear localization of AFT complexes that is identical to conventional fluorescence-tagged constructs. Production of the BiFC signal is dependent on the adaptor protein Fe65 resulting in fluorescence complementation only after Fe65-mediated nuclear translocation of AICD and interaction with Tip60. We applied the AFT-BiFC system to show that the Swedish APP familial Alzheimer's disease mutation increases AFT complex formation, consistent with the notion that AICD mediated nuclear signaling mainly occurs following APP processing through the amyloidogenic β-secretase pathway. Next, we studied the impact of posttranslational modifications of AICD on AFT complex formation. Mutation of tyrosine 682 in the YENPTY motif of AICD to phenylalanine prevents phosphorylation resulting in increased nuclear AFT-BiFC signals. This is consistent with the negative impact of tyrosine phosphorylation on Fe65 binding to AICD. Finally, we studied the effect of oxidative stress. Our data shows that oxidative stress, at a level that also causes cell death, leads to a reduction in AFT-BiFC signals. CONCLUSION: We established a new method for visualization and FC quantification of the interaction between

  13. An old HAT in human p300/CBP and yeast Rtt109.

    Science.gov (United States)

    Bazan, J Fernando

    2008-06-15

    The crystal structure of the human p300 histone acetyltransferase (HAT) domain reveals a familiar alpha + beta fold with unique structural elaborations that merit its classification as a third divergent HAT branch alongside the GCN5-related N-acetyltransferase (GNAT) and MYST (MOZ, Ybf2/Sas3, Sas2, Tip60) families. Two key departures from the core GNAT/MYST HAT fold--a long unstructured chain (or "flap") overlaying the acetyl-CoA (AcCoA) binding groove, and a four-alpha-helix "tower" excursion from the main beta-sheet--critically contribute to the recognition and presumptive catalytic machinery of p300/CBP HAT enzymes. Kinetic and mutant analysis of this enlarged residue constellation in p300 (which is distinct from functional fingerprints drawn from GNAT or MYST complexes) led Liu et al., to suggest that p300/CBP works with an unorthodox "hit and run" mechanism that enlists Tyr1467 as the critical catalytic residue. In order to extend the evolutionary testbed for this variant HAT mechanism beyond the thin roll of p300/CBP orthologs, I propose that Rtt109, a novel yeast HAT that has so far eluded classification, is the prototype of a fungal clan of p300-related enzymes that preserve the embellished HAT fold, but further diversify its catalytic options. PMID:18583929

  14. Analysis of Myc-induced histone modifications on target chromatin.

    Directory of Open Access Journals (Sweden)

    Francesca Martinato

    Full Text Available The c-myc proto-oncogene is induced by mitogens and is a central regulator of cell growth and differentiation. The c-myc product, Myc, is a transcription factor that binds a multitude of genomic sites, estimated to be over 10-15% of all promoter regions. Target promoters generally pre-exist in an active or poised chromatin state that is further modified by Myc, contributing to fine transcriptional regulation (activation or repression of the afferent gene. Among other mechanisms, Myc recruits histone acetyl-transferases to target chromatin and locally promotes hyper-acetylation of multiple lysines on histones H3 and H4, although the identity and combination of the modified lysines is unknown. Whether Myc dynamically regulates other histone modifications (or marks at its binding sites also remains to be addressed. Here, we used quantitative chromatin immunoprecipitation (qChIP to profile a total of 24 lysine-acetylation and -methylation marks modulated by Myc at target promoters in a human B-cell line with a regulatable c-myc transgene. Myc binding promoted acetylation of multiple lysines, primarily of H3K9, H3K14, H3K18, H4K5 and H4K12, but significantly also of H4K8, H4K91 and H2AK5. Dimethylation of H3K79 was also selectively induced at target promoters. A majority of target promoters showed co-induction of multiple marks - in various combinations - correlating with recruitment of the two HATs tested (Tip60 and HBO1, incorporation of the histone variant H2A.Z and transcriptional activation. Based on this and previous findings, we surmise that Myc recruits the Tip60/p400 complex to achieve a coordinated histone acetylation/exchange reaction at activated promoters. Our data are also consistent with the additive and redundant role of multiple acetylation events in transcriptional activation.

  15. Composition and biological significance of the human Nα-terminal acetyltransferases

    OpenAIRE

    Starheim, Kristian K; Gromyko, Darina; Velde, Rolf; Varhaug, Jan Erik; Arnesen, Thomas

    2009-01-01

    Protein Nα-terminal acetylation is one of the most common protein modifications in eukaryotic cells, occurring on approximately 80% of soluble human proteins. An increasing number of studies links Nα-terminal acetylation to cell differentiation, cell cycle, cell survival, and cancer. Thus, Nα-terminal acetylation is an essential modification for normal cell function in humans. Still, little is known about the functional role of Nα-terminal acetylation. Recently, the three major human N-acetyl...

  16. Histone acetyltransferases are crucial regulators in NF-kappa B mediated inflammation

    NARCIS (Netherlands)

    Ghizzoni, Massimo; Haisma, Hidde J.; Maarsingh, Harm; Dekker, Frank J.

    2011-01-01

    Post-translational modifications of proteins, such as acetylation, are important regulatory events in eukaryotic cells. Reversible acetylations of histones and non-histone proteins regulate gene expression and protein activity. Acetylation levels of proteins are regulated by a dynamic equilibrium be

  17. [The relationship between passive smoking, breast cancer risk and n-acetyltransferase 2 (NAT2)].

    Science.gov (United States)

    Avraham, Zipora; Baron-Epel, Orna; Boker, Lital Keinan

    2014-01-01

    Invasive breast cancer is a leading cause of morbidity and mortality as well as the most common malignancy among Israeli women. Over 3,800 Israeli women are diagnosed with invasive breast cancer every year and around 3400 women are diagnosed with breast carcinoma in-situ. Although smoking, either active or passive, is a controversial risk factor for breast cancer, cigarette smoking involves exposure to substrates of the NAT2 gene. The NAT2 genotype may modify the risk of cancer by activating or detoxifying heterocyclic and aromatic amines. Identification of a potential, modifiable risk factor for common and serious disease is very important for prevention and identification of high risk groups. This literature review aims to describe published studies and increase attention to measures of exposure to tobacco smoke, as well as to aspects of the NAT2 genotype that may modify the association between passive smoking and breast cancer risk. The results suggest that the NAT2 status has a differential effect on the association of active and passive smoking with breast cancer and demonstrates the need to consider possible different mechanisms associated with exposure to main and side-stream tobacco smoke. However, methodological limitations, such as small sample size, and varying definitions of smoking, are likely to have contributed to the inconsistent findings. PMID:24791559

  18. N-acetyltransferase 2 polymorphisms and risk of esophageal cancer in a Chinese population.

    Directory of Open Access Journals (Sweden)

    Liming Wang

    Full Text Available Esophageal cancer was the fifth most commonly diagnosed cancer and the fourth leading cause of cancer-related death in China in 2009. Genetic factors might play an important role in the carcinogenesis of esophageal squamous cell carcinoma (ESCC. We conducted a hospital-based case-control study to evaluate ten NAT2 tagging single nucleotide polymorphisms (SNPs on the risk of ESCC. Six hundred and twenty-nine ESCC cases and 686 controls were recruited. Their genotypes were determined using the ligation detection reaction method. In the single locus analyses, there was a borderline statistically significant difference in genotype frequencies of NAT2 rs1565684 T>C SNP between the cases and the controls (p = 0.057. The NAT2 rs1565684 CC genotype was associated with a borderline significantly increased risk for ESCC (CC vs. TT: adjusted OR = 1.77, 95% CI = 0.97-3.21, p = 0.063 and CC vs. TT/TC: adjusted OR = 1.68, 95% CI = 0.93-3.04, p = 0.085. The association was evident among older patients and patients who never drunk. After the Bonferroni correction, in all comparison models, NAT2 rs1565684 T>C SNP was not associated with ESCC risk (p>0.05. For the other nine NAT2 SNPs, after Bonferroni correction, in all comparison models, the nine SNPs were also not associated with ESCC risk (p>0.05. Thus, nine NAT2 tagging SNPs were not associated with risk of ESCC. NAT2 rs1565684 T>C SNP might play a slight role in ESCC etiology. Additional, larger studies and tissue-specific biological characterization are required to confirm the current findings.

  19. The Essential Cofactor TRRAP Recruits the Histone Acetyltransferase hGCN5 to c-Myc

    Science.gov (United States)

    McMahon, Steven B.; Wood, Marcelo A.; Cole, Michael D.

    2000-01-01

    The c-Myc protein functions as a transcription factor to facilitate oncogenic transformation; however, the biochemical and genetic pathways leading to transformation remain undefined. We demonstrate here that the recently described c-Myc cofactor TRRAP recruits histone acetylase activity, which is catalyzed by the human GCN5 protein. Since c-Myc function is inhibited by recruitment of histone deacetylase activity through Mad family proteins, these opposing biochemical activities are likely to be responsible for the antagonistic biological effects of c-Myc and Mad on target genes and ultimately on cellular transformation. PMID:10611234

  20. Effect of Increased Yeast Alcohol Acetyltransferase Activity on Flavor Profiles of Wine and Distillates

    OpenAIRE

    Lilly, M.; Lambrechts, M. G.; Pretorius, I S

    2000-01-01

    The distinctive flavor of wine, brandy, and other grape-derived alcoholic beverages is affected by many compounds, including esters produced during alcoholic fermentation. The characteristic fruity odors of the fermentation bouquet are primarily due to a mixture of hexyl acetate, ethyl caproate (apple-like aroma), iso-amyl acetate (banana-like aroma), ethyl caprylate (apple-like aroma), and 2-phenylethyl acetate (fruity, flowery flavor with a honey note). The objective of this study was to in...

  1. The molecular mechanism underlying Roberts syndrome involves loss of ESCO2 acetyltransferase activity

    DEFF Research Database (Denmark)

    Gordillo, M.; Vega, H.; Trainer, A.H.;

    2008-01-01

    on enzymatic activity and cellular phenotype. We found that ESCO2 W539G results in loss of autoacetyltransferase activity. The cellular phenotype produced by this mutation causes cohesion defects, proliferation capacity reduction and mitomycin C sensitivity equivalent to those produced by frameshift...

  2. Investigation of MYST4 histone acetyltransferase and its involvement in mammalian gametogenesis

    Directory of Open Access Journals (Sweden)

    Sirard Marc-André

    2007-11-01

    Full Text Available Abstract Background Various histone acetylases (HATs play a critical role in the regulation of gene expression, but the precise functions of many of those HATs are still unknown. Here we provide evidence that MYST4, a known HAT, may be involved in early mammalian gametogenesis. Results Although MYST4 mRNA transcripts are ubiquitous, protein expression was restricted to select extracts (including ovary and testis. Immunohistochemistry experiments performed on ovary sections revealed that the MYST4 protein is confined to oocytes, granulosa and theca cells, as well as to cells composing the blood vessels. The transcripts for MYST4 and all-MYST4-isoforms were present in oocytes and in in vitro produced embryos. In oocytes and embryos the MYST4 protein was localized in both the cytoplasm and nucleus. Within testis sections, the MYST4 protein was specific to only one cell type, the elongating spermatids, where it was exclusively nuclear. Conclusion We established that MYST4 is localized into specialized cells of the ovary and testis. Because the majority of these cells are involved in male and female gametogenesis, MYST4 may contribute to important and specific acetylation events occurring during gametes and embryo development.

  3. Para-phenylenediamine and allergic sensitization : risk modification by N-acetyltransferase 1 and 2 genotypes

    NARCIS (Netherlands)

    Bloemeke, B.; Brans, R.; Coenraads, P. -J.; Dickel, H.; Bruckner, T.; Hein, D. W.; Heesen, M.; Merk, H. -F.; Kawakubo, Y.; Blomeke, B.

    2009-01-01

    Background Para-phenylenediamine (PPD) is a common contact sensitizer causing allergic contact dermatitis, a major skin problem. As PPD may need activation to become immunogenic, the balance between activation and/or detoxification processes may influence an individual's susceptibility. PPD is acety

  4. N-Acetyltransferase 2 (NAT2) in Tunisian Population: Correlation Between Acetylation Phenotype and Genotype

    International Nuclear Information System (INIS)

    One hundred tuberculous patients were studied during 2004-2005 to determine acetylation phenotype, frequent mutations of NAT2 gene and to compare acetylation phenotype with NAT2 genotype in Tunisian population. Acetylation phenotype was determined by determination of acetylation index. Five mutations of NAT2 gene were evaluated by PCR/RFLP. Results show bimodal distribution of acetylation SA and RA phenotype, 75% and 25% and genotype 56% and 44%, respectively. Ten NAT2 alleles were found, NAT2*4 being the major one. Thirty-two different genotypes were found (9 RA and 23 SA). The major one was NAT2*6 B/NAT2*4. The concordance value was 79%. A good sensibility (98, 2%) of acetylation test for SA detection was found. Thus, acetylation phenotype in SA is predicted with poor error risk. (author)

  5. Structural and functional characterization of an arylamine N-acetyltransferase from the pathogen Mycobacterium abscessus

    DEFF Research Database (Denmark)

    Cocaign, Angélique; Kubiak, Xavier Jean Philippe; Xu, Ximing;

    2014-01-01

    Mycobacterium abscessus is the most pathogenic rapid-growing mycobacterium and is one of the most resistant organisms to chemotherapeutic agents. However, structural and functional studies of M. abscessus proteins that could modify/inactivate antibiotics remain nonexistent. Here, the structural a...

  6. Sulphoacetaldehyde acetyltransferase yields acetyl phosphate : purification from Alcaligenes defragrans and gene clusters in taurine degradation

    OpenAIRE

    Ruff, Jürgen; Denger, Karin; Cook, Alasdair M.

    2003-01-01

    The facultatively anaerobic bacterium Alcaligenes defragrans NKNTAU was found to oxidize taurine (2-aminoethanesulphonate) with nitrate as the terminal electron acceptor. Taurine was transaminated to 2-sulphoacetaldehyde. This was not converted into sulphite and acetate by a "sulphoacetaldehyde sulpho-lyase" (EC 4.4.1.12), but into sulphite and acetyl phosphate, which was identified by three methods. The enzyme, which required the addition of phosphate, thiamin diphosphate and Mg(2+) ions for...

  7. Engineered defective interfering RNAs of Sindbis virus express bacterial chloramphenicol acetyltransferase in avian cells.

    OpenAIRE

    Levis, R; Huang, H.; Schlesinger, S

    1987-01-01

    We are investigating the feasibility of using the positive-strand RNA virus Sindbis virus and its defective interfering (DI) particles as vectors for introducing foreign genes into cells. In previous work we showed by deletion mapping of a cloned cDNA derived from one of the DI RNAs that only nucleotides at the 3' and 5' termini of the RNA are essential for the DI RNA to be amplified after it is transfected into cells in the presence of helper virus. As a first step in developing a vector we ...

  8. Basic nuclear processes affected by histone acetyltransferases and histone deacetylase inhibitors

    NARCIS (Netherlands)

    Legartová, Soňa; Stixová, Lenka; Strnad, Hynek; Kozubek, Stanislav; Martinet, Nadine; Dekker, Frank J; Franek, Michal; Bártová, Eva

    2013-01-01

    AIM: The optimal balance between histone acetylation and deacetylation is important for proper gene function. Therefore, we addressed how inhibitors of histone-modifying enzymes can modulate nuclear events, including replication, transcription, splicing and DNA repair. MATERIALS & METHODS: Changes i

  9. Adipogenic Activity of Wild Populations of Rhododendron groenlandicum, a Medicinal Shrub from the James Bay Cree Traditional Pharmacopeia

    OpenAIRE

    Michel Rapinski; Lina Musallam; John Thor Arnason; Pierre Haddad; Alain Cuerrier

    2015-01-01

    The traditional medicinal plant, Labrador tea (Rhododendron groenlandicum (Oeder) Kron & Judd; Ericaceae), present in the pharmacopoeia of the Cree of Eeyou Istchee, has shown glitazone-like activity in the 3T3-L1 adipogenesis bioassay. This activity has been attributed to phenolic compounds, which have been shown to vary in this plant as a function of insolation parameters. The goal of this study was to determine if these changes in phenolic content were pharmacologically significant. Leaves...

  10. AMP-activated protein kinase is required for the anti-adipogenic effects of alpha-linolenic acid

    OpenAIRE

    Zhou, Xihong; Wu, Weiche; Chen, Jingqing; Wang, Xinxia; Wang, Yizhen

    2015-01-01

    Background n-3 long chain polyunsaturated fatty acid (n-3 LC PUFA) increases β-oxidation and limits lipid accumulation in adipocytes. The current study was conducted to determine whether their precursor alpha-linolenic acid (ALA) could also exert the above effects and how AMP-activated protein kinase (AMPK) was involved. Methods AMPKα1−/−, AMPKα2−/− mice and wild-type (WT) mice were fed a high-fat diet (HFD) or HFD with ALA. Body weight was recorded weekly and serum was collected. Adipocytes ...

  11. The Role of Paracrine and Autocrine Signaling in the Early Phase of Adipogenic Differentiation of Adipose-derived Stem Cells

    DEFF Research Database (Denmark)

    Hemmingsen, Mette; Vedel, Søren; Skafte-Pedersen, Peder;

    2013-01-01

    Using different cell densities and microfluidic perfusion cell cultures to suppress the effects of cell-released factors, we have demonstrated the significant role played by auto- or paracrine signaling in adipocyte differentiation. The cell-released factor(s) were shown to act in the recruitment...

  12. Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Li-Wu [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Wu, Qiangen [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Green, Bridgett; Nolen, Greg [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Shi, Leming [Division of Systems Biology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); LoSurdo, Jessica [Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892 (United States); Deng, Helen [Arkansas Department of Health, Little Rock, AR 72205 (United States); Bauer, Steven [Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892 (United States); Fang, Jia-Long, E-mail: jia-long.fang@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Ning, Baitang, E-mail: baitang.ning@fda.hhs.gov [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States)

    2012-07-15

    Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCS (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.

  13. Piceatannol Exerts Anti-Obesity Effects in C57BL/6 Mice through Modulating Adipogenic Proteins and Gut Microbiota

    Directory of Open Access Journals (Sweden)

    Yen-Chen Tung

    2016-10-01

    Full Text Available Obesity is a global health concern. Piceatannol (Pic, an analog of resveratrol (Res, has many reported biological activities. In this study, we investigated the anti-obesity effect of Pic in a high-fat diet (HFD-induced obese animal model. The results showed that Pic significantly reduced mouse body weight in a dose-dependent manner without affecting food intake. Serum total cholesterol (TC, low-density lipoprotein (LDL, high-density lipoprotein (HDL levels, and blood glucose (GLU were significantly lowered in Pic-treated groups. Pic significantly decreased the weight of liver, spleen, perigonadal and retroperitoneal fat compared with the HFD group. Pic significantly reduced the adipocyte cell size of perigonadal fat and decreased the weight of liver. Pic-treated mice showed higher phosphorylated adenosine 5′-monophosphate-activated protein kinase (pAMPK and phosphorylated acetyl-CoA carboxylase (pACC protein levels and decreased protein levels of CCAAT/enhancer-binding protein C/EBPα, peroxisome proliferator-activated receptor PPARγ and fatty acid synthase (FAS, resulting in decreased lipid accumulation in adipocytes and the liver. Pic altered the composition of the gut microbiota by increasing Firmicutes and Lactobacillus and decreasing Bacteroidetes compared with the HFD group. Collectively, these results suggest that Pic may be a candidate for obesity treatment.

  14. Myotube formation is affected by adipogenic lineage cells in a cell-to-cell contact-independent manner

    Energy Technology Data Exchange (ETDEWEB)

    Takegahara, Yuki; Yamanouchi, Keitaro, E-mail: akeita@mail.ecc.u-tokyo.ac.jp; Nakamura, Katsuyuki; Nakano, Shin-ichi; Nishihara, Masugi

    2014-05-15

    Intramuscular adipose tissue (IMAT) formation is observed in some pathological conditions such as Duchenne muscular dystrophy (DMD) and sarcopenia. Several studies have suggested that IMAT formation is not only negatively correlated with skeletal muscle mass but also causes decreased muscle contraction in sarcopenia. In the present study, we examined w hether adipocytes affect myogenesis. For this purpose, skeletal muscle progenitor cells were transfected with siRNA of PPARγ (siPPARγ) in an attempt to inhibit adipogenesis. Myosin heavy chain (MHC)-positive myotube formation was promoted in cells transfected with siPPARγ compared to that of cells transfected with control siRNA. To determine whether direct cell-to-cell contact between adipocytes and myoblasts is a prerequisite for adipocytes to affect myogenesis, skeletal muscle progenitor cells were cocultured with pre- or mature adipocytes in a Transwell coculture system. MHC-positive myotube formation was inhibited when skeletal muscle progenitor cells were cocultured with mature adipocytes, but was promoted when they were cocultured with preadipocytes. Similar effects were observed when pre- or mature adipocyte-conditioned medium was used. These results indicate that preadipocytes play an important role in maintaining skeletal muscle mass by promoting myogenesis; once differentiated, the resulting mature adipocytes negatively affect myogenesis, leading to the muscle deterioration observed in skeletal muscle pathologies. - Highlights: • We examined the effects of pre- and mature adipocytes on myogenesis in vitro. • Preadipocytes and mature adipocytes affect myoblast fusion. • Preadipocytes play an important role in maintaining skeletal muscle mass. • Mature adipocytes lead to muscle deterioration observed in skeletal muscle pathologies.

  15. "The preadipocyte factor" DLK1 marks adult mouse adipose tissue residing vascular cells that lack in vitro adipogenic differentiation potential

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Jensen, Line; Schrøder, Henrik Daa;

    2009-01-01

    Delta-like 1 (Dlk1) is expressed in 3T3-L1 preadipocytes and has frequently been referred to as "the" preadipocyte marker, yet the phenotype of DLK1(+) cells in adipose tissue remains undetermined. Herein, we demonstrate that DLK1(+) cells encompass around 1-2% of the adult mouse adipose stromal......, generation of tube-like structures on matrigel, and uptake of Acetylated Low Density-Lipoprotein, all characteristics of endothelial cells. We therefore suggest that DLK1(+)SVF cells are of a vascular origin and not them-selves committed preadipocytes as assumed hitherto....

  16. Normal Leptin Expression, Lower Adipogenic Ability, Decreased Leptin Receptor and Hyposensitivity to Leptin in Adolescent Idiopathic Scoliosis

    OpenAIRE

    Guoyan Liang; Wenjie Gao; Anjing Liang; Wei Ye; Yan Peng; Liangming Zhang; Swarkar Sharma; Peiqiang Su; Dongsheng Huang

    2012-01-01

    Leptin has been suggested to play a role in the etiology of Adolescent Idiopathic Scoliosis (AIS), however, the leptin levels in AIS girls are still a discrepancy, and no in vitro study of leptin in AIS is reported. We took a series of case-control studies, trying to understand whether Leptin gene polymorphisms are involved in the etiology of the AIS or the change in leptin level is a secondary event, to assess the level of leptin receptor, and to evaluate the differences of response to lepti...

  17. Cytoskeletal and Focal Adhesion Influences on Mesenchymal Stem Cell Shape, Mechanical Properties, and Differentiation Down Osteogenic, Adipogenic, and Chondrogenic Pathways

    OpenAIRE

    Mathieu, Pattie S.; Loboa, Elizabeth G

    2012-01-01

    Mesenchymal stem cells (MSCs) hold great potential for regenerative medicine and tissue-engineering applications. They have multipotent differentiation capabilities and have been shown to differentiate down various lineages, including osteoblasts, adipocytes, chondrocytes, myocytes, and possibly neurons. The majority of approaches to control the MSC fate have been via the use of chemical factors in the form of growth factors within the culture medium. More recently, it has been understood tha...

  18. Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

    International Nuclear Information System (INIS)

    Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCS (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.

  19. MRG15 activates the cdc2 promoter via histone acetylation in human cells

    Energy Technology Data Exchange (ETDEWEB)

    Pena, AndreAna N., E-mail: andreana.pena@gmail.com [Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX (United States); Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX (United States); Tominaga, Kaoru; Pereira-Smith, Olivia M. [Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX (United States); Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX (United States)

    2011-07-01

    Chromatin remodeling is required for transcriptional activation and repression. MRG15 (MORF4L1), a chromatin modulator, is a highly conserved protein and is present in complexes containing histone acetyltransferases (HATs) as well as histone deacetylases (HDACs). Loss of expression of MRG15 in mice and Drosophila results in embryonic lethality and fibroblast and neural stem/progenitor cells cultured from Mrg15 null mouse embryos exhibit marked proliferative defects when compared with wild type cells. To determine the role of MRG15 in cell cycle progression we performed chromatin immunoprecipitation with an antibody to MRG15 on normal human fibroblasts as they entered the cell cycle from a quiescent state, and analyzed various cell cycle gene promoters. The results demonstrated a 3-fold increase in MRG15 occupancy at the cdc2 promoter during S phase of the cell cycle and a concomitant increase in acetylated histone H4. H4 lysine 12 was acetylated at 24 h post-serum stimulation while there was no change in acetylation of lysine 16. HDAC1 and 2 were decreased at this promoter during cell cycle progression. Over-expression of MRG15 in HeLa cells activated a cdc2 promoter-reporter construct in a dose-dependent manner, whereas knockdown of MRG15 resulted in decreased promoter activity. In order to implicate HAT activity, we treated cells with the HAT inhibitor anacardic acid and determined that HAT inhibition results in loss of expression of cdc2 mRNA. Further, chromatin immunoprecipitation with Tip60 localizes the protein to the same 110 bp stretch of the cdc2 promoter pulled down by MRG15. Additionally, we determined that cotransfection of MRG15 with the known associated HAT Tip60 had a cooperative effect in activating the cdc2 promoter. These results suggest that MRG15 is acting in a HAT complex involving Tip60 to modify chromatin via acetylation of histone H4 at the cdc2 promoter to activate transcription.

  20. BAF53 Forms Distinct Nuclear Complexes and Functions as a Critical c-Myc-Interacting Nuclear Cofactor for Oncogenic Transformation

    Science.gov (United States)

    Park, Jeonghyeon; Wood, Marcelo A.; Cole, Michael D.

    2002-01-01

    The c-Myc oncoprotein functions as a transcription factor that can transform normal cells into tumor cells, as well as playing a direct role in normal cell proliferation. The c-Myc protein transactivates cellular promoters by recruiting nuclear cofactors to chromosomal sites through an N-terminal transactivation domain. We have previously reported the identification and functional characterization of four different c-Myc cofactors: TRRAP, hGCN5, TIP49, and TIP48. Here we present the identification and characterization of the actin-related protein BAF53 as a c-Myc-interacting nuclear cofactor that forms distinct nuclear complexes. In addition to the human SWI/SNF-related BAF complex, BAF53 forms a complex with TIP49 and TIP48 and a separate biochemically distinct complex containing TRRAP and a histone acetyltransferase which does not contain TIP60. Using deletion mutants of BAF53, we show that BAF53 is critical for c-Myc oncogenic activity. Our results indicate that BAF53 plays a functional role in c-Myc-interacting nuclear complexes. PMID:11839798

  1. Spermidine/spermine N-1-acetyltransferase specifically binds to the integrin alpha 9 subunit cytoplasmic domain and enhances cell migration

    OpenAIRE

    Chen, C.; Young, B A; Coleman, C S; Pegg, A E; Sheppard, D

    2004-01-01

    T he integrin alpha9beta1 is expressed on migrating cells, such as leukocytes, and binds to multiple ligands that are present at sites of tissue injury and inflammation. alpha9beta1, like the structurally related integrin alpha4beta1, mediates accelerated cell migration, an effect that depends on the beta cytoplasmic domain. alpha4beta1 enhances migration through reversible binding to the adapter protein, paxillin, but alpha9beta1-dependent migration is paxillin independent. Using yeast two-h...

  2. Inhibition of different histone acetyltransferases (HATs) uncovers transcription-dependent and -independent acetylation-mediated mechanisms in memory formation.

    Science.gov (United States)

    Merschbaecher, Katja; Hatko, Lucyna; Folz, Jennifer; Mueller, Uli

    2016-02-01

    Acetylation of histones changes the efficiency of the transcription processes and thus contributes to the formation of long-term memory (LTM). In our comparative study, we used two inhibitors to characterize the contribution of different histone acetyl transferases (HATs) to appetitive associative learning in the honeybee. For one we applied garcinol, an inhibitor of the HATs of the p300 (EP300 binding protein)/CBP (CREB-binding protein) family, and the HATs of the PCAF (p300/CBP-associated factor) family. As comparative agent we applied C646, a specific inhibitor that selectively blocks HATS of the p300/CBP family. Immunochemical analysis reveals differences in histone H3 acetylation in the honeybee brain, in response to the injection of either C646 or garcinol. Behavioral assessment reveals that the two drugs cause memory impairment of different nature when injected after associative conditioning: processes disturbed by garcinol are annihilated by the established transcription blocker actinomycin D and thus seem to require transcription processes. Actions of C646 are unaltered by actinomycin D, and thus seem to be independent of transcription. The outcome of our different approaches as summarized suggests that distinct HATs contribute to different acetylation-mediated processes in memory formation. We further deduce that the acetylation-mediated processes in memory formation comprise transcription-dependent and transcription-independent mechanisms.

  3. Genetic variants in the choline acetyltransferase (ChAT) gene are modestly associated with normal cognitive function in the elderly

    DEFF Research Database (Denmark)

    Mengel-From, J; Christensen, K; Thinggaard, M;

    2011-01-01

    and singletons (N = 2070). The ChAT rs3810950 A allele, which has been associated with increased risk for AD, was found to be associated with a decrease cognitive status evaluated by a five-component cognitive composite score [P = 0.03, regression coefficient -0.30, 95% confidence interval (CI) -0.57 to -0.......02], and the rs3810950 and rs8178990 ancestral GC haplotype was also associated with better cross-sectional cognitive composite score (P = 0.04, regression coefficient 0.59, 95% CI 0.03 to 1.16). Growth curve model analyses applied to up to 10 years of follow-up data showed that the rs3810950 A allele...... was associated with a lower cognitive composite score and Mini Mental State Examination at the lowest age (73 years of age), and was lower in the whole interval 73-82 although the absolute difference became smaller with age. Stratification by the presence of the APOE ε4 allele showed that rs3810950 AG/non-APOE ε...

  4. Relationships between choline acetyl-transferase and muscarinic binding in aging rodent brain and in Alzheimers disease

    International Nuclear Information System (INIS)

    This paper examines how the relation between ChAT and muscarinic binding might be affected by aging in mouse and rat brains. Preliminary data are presented regarding this relation in postmortem cerebral cortex samples from human subjects who died with Alzheimer's disease (AD) and from age-matched controls. The effect of acetyl coenzme A (1- C 14-acetyl coenzyme A concentration on enzyme activity was determined by varying the concentration of the coenzyme in the assay medium. Assays of muscarinic binding were performed on tissue sonicates diluted with Tris-HC1 buffer using tritium-quinuclidinyl benzilate tritium-QNB as the ligand. For brain regions obtained from rats, significance of age differences were assessed by one-way analysis of variance and Bonferroni t statistics. Differences in ChAT activity and binding site density from human postmortem samples between diagnostic groups were assessed separately by region using an analysis of covariance

  5. Phylogenetische und funktionelle Analysen zur Kapsel O-Acetyltransferase NeuO von Escherichia coli K1

    OpenAIRE

    Mordhorst, Ines Louise

    2010-01-01

    Escherichia coli ist ein Kommensale des menschlichen und tierischen Gastrointestinaltraktes. Einige E. coli-Stämme sind in der Lage, extraintestinale Erkrankungen beim Menschen wie Harnwegsinfekte, Neugeborenen-Meningitis und Sepsis, sowie beim Tier aviäre Coliseptikämien, hervorzurufen. Ein wichtiger Virulenzfaktor des Bakteriums ist dabei die aus α-2,8-verknüpften Sialinsäuremonomeren aufgebaute K1-Kapsel, die phasenvariabel mit einer hohen Frequenz O-acetyliert werden kann. Im Jahr 20...

  6. Expression of an engineered granule-bound Escherichia coli maltose acetyltransferase in wild-type and amf potato plants

    NARCIS (Netherlands)

    Nazarian, F.; Vincken, J.P.; Qin, J.; Suurs, L.C.J.M.; Visser, R.G.F.

    2007-01-01

    Starch is used in many industrial applications, but often requires chemical derivatization to enhance its properties before use. In particular, the stability of starch polymers in solution is improved by acetylation. A drawback of this treatment is the use of pollutant chemicals. A biological altern

  7. NAA10 mutation causing a novel intellectual disability syndrome with Long QT due to N-terminal acetyltransferase impairment

    Science.gov (United States)

    Casey, Jillian P.; Støve, Svein I.; McGorrian, Catherine; Galvin, Joseph; Blenski, Marina; Dunne, Aimee; Ennis, Sean; Brett, Francesca; King, Mary D.; Arnesen, Thomas; Lynch, Sally Ann

    2015-01-01

    We report two brothers from a non-consanguineous Irish family presenting with a novel syndrome characterised by intellectual disability, facial dysmorphism, scoliosis and long QT. Their mother has a milder phenotype including long QT. X-linked inheritance was suspected. Whole exome sequencing identified a novel missense variant (c.128 A > C; p.Tyr43Ser) in NAA10 (X chromosome) as the cause of the family’s disorder. Sanger sequencing confirmed that the mutation arose de novo in the carrier mother. NAA10 encodes the catalytic subunit of the major human N-terminal acetylation complex NatA. In vitro assays for the p.Tyr43Ser mutant enzyme showed a significant decrease in catalytic activity and reduced stability compared to wild-type Naa10 protein. NAA10 has previously been associated with Ogden syndrome, Lenz microphthalmia syndrome and non-syndromic developmental delay. Our findings expand the clinical spectrum of NAA10 and suggest that the proposed correlation between mutant Naa10 enzyme activity and phenotype severity is more complex than anticipated; the p.Tyr43Ser mutant enzyme has less catalytic activity than the p.Ser37Pro mutant associated with lethal Ogden syndrome but results in a milder phenotype. Importantly, we highlight the need for cardiac assessment in males and females with NAA10 variants as both patients and carriers can have long QT. PMID:26522270

  8. N-acetyltransferase 2 (NAT2 Gene Polymorphisms and the Effectiveness of Infertility Treatment in Patients with Peritoneal Endometriosis

    Directory of Open Access Journals (Sweden)

    Ekaterina D. Dubinskaya

    2014-03-01

    Full Text Available Today, infertility has become a global issue. WHO ranks it the fifth among the major diseases of those below 60 years, after alcoholism, depression, injuries and eyesight disorders. Numerous studies conducted on the problems of infertility in endometriosis still do not offer clear answers regarding the pathogenesis and mechanisms of this disease and its influences on fertility. According to the survey results, point mutations of the NAT2 gene (NAT2*5 and NAT2*6 have been identified in 75.6% of the patients with infertility problems and the peritoneal form of endometriosis, that create “slow” allelic variants, which exceed the average index in the population. The peculiarities of the NAT2 gene polymorphisms have been proven to be associated with the effectiveness of the infertility treatment of female patients with peritoneal endometriosis. In the group of non-pregnant patients, the presence of с.341Т>C, c.481C>T, c.590G>A and c.803A>G heterozygous point mutations are 73.2, 73.2, 5.4, and 62.5%, respectively. The significant difference in the comparison of the allelic polymorphism during the various stages of the endometriosis was not identified. At stage III-IV endometriosis the frequency of three and more point substitutions was significantly higher. NAT2 gene polymorphisms can find use as an additional criterion for predicting the effectiveness of the infertility treatment of patients with peritoneal endometriosis.

  9. Inhibition of Different Histone Acetyltransferases (HATs) Uncovers Transcription-Dependent and -Independent Acetylation-Mediated Mechanisms in Memory Formation

    Science.gov (United States)

    Merschbaecher, Katja; Hatko, Lucyna; Folz, Jennifer; Mueller, Uli

    2016-01-01

    Acetylation of histones changes the efficiency of the transcription processes and thus contributes to the formation of long-term memory (LTM). In our comparative study, we used two inhibitors to characterize the contribution of different histone acetyl transferases (HATs) to appetitive associative learning in the honeybee. For one we applied…

  10. p300/CBP Histone Acetyltransferase Activity Is Required for Newly Acquired and Reactivated Fear Memories in the Lateral Amygdala

    Science.gov (United States)

    Maddox, Stephanie A.; Watts, Casey S.; Schafe, Glenn E.

    2013-01-01

    Modifications in chromatin structure have been widely implicated in memory and cognition, most notably using hippocampal-dependent memory paradigms including object recognition, spatial memory, and contextual fear memory. Relatively little is known, however, about the role of chromatin-modifying enzymes in amygdala-dependent memory formation.…

  11. Depot specific differences in the adipogenic potential of precursors are mediated by collagenous extracellular matrix and Flotillin 2 dependent signaling

    Directory of Open Access Journals (Sweden)

    Gerald Grandl

    2016-10-01

    Conclusions: We show that adipose tissue SVF secretes collagenous ECM, which directly modulates terminal differentiation of adipocyte precursors in a depot specific manner. These data demonstrate the importance of the tissue microenvironment in preadipocyte differentiation.

  12. Transgelin is a TGFβ-inducible gene that regulates osteoblastic and adipogenic differentiation of human skeletal stem cells through actin cytoskeleston organization

    DEFF Research Database (Denmark)

    Elsafadi, E; Manikandan, M; Dawud, RA;

    2016-01-01

    bone marrow-derived stromal (skeletal) stem cells (hMSC). siRNA-mediated gene silencing of TAGLN impaired lineage differentiation into osteoblasts and adipocytes but enhanced cell proliferation. Additional functional studies revealed that TAGLN deficiency impaired hMSC cell motility and in vitro...... transwell cell migration. On the other hand, TAGLN overexpression reduced hMSC cell proliferation, but enhanced cell migration, osteoblastic and adipocytic differentiation, and in vivo bone formation. In addition, deficiency or overexpression of TAGLN in hMSC was associated with significant changes...... in cellular and nuclear morphology and cytoplasmic organelle composition as demonstrated by high content imaging and transmission electron microscopy that revealed pronounced alterations in the distribution of the actin filament and changes in cytoskeletal organization. Molecular signature of TAGLN...

  13. Verification of suitable and reliable reference genes for quantitative real-time PCR during adipogenic differentiation in porcine intramuscular stromal-vascular cells.

    Science.gov (United States)

    Li, X; Huang, K; Chen, F; Li, W; Sun, S; Shi, X-E; Yang, G

    2016-06-01

    Intramuscular fat (IMF) is an important trait influencing meat quality, and intramuscular stromal-vascular cell (MSVC) differentiation is a key factor affecting IMF deposition. Quantitative real-time PCR (qPCR) is often used to screen the differentially expressed genes during differentiation of MSVCs, where proper reference genes are essential. In this study, we assessed 31 of previously reported reference genes for their expression suitability in porcine MSVCs derived form longissimus dorsi with qPCR. The expression stability of these genes was evaluated using NormFinder, geNorm and BestKeeper algorithms. NormFinder and geNorm uncovered ACTB, ALDOA and RPS18 as the most three stable genes. BestKeeper identified RPL13A, SSU72 and DAK as the most three stable genes. GAPDH was found to be the least stable gene by all of the three software packages, indicating it is not an appropriate reference gene in qPCR assay. These results might be helpful for further studies in pigs that explore the molecular mechanism underlying IMF deposition.

  14. Novel Function of Serine Protease HTRA1 in Inhibiting Adipogenic Differentiation of Human Mesenchymal Stem Cells via MAP Kinase-Mediated MMP Upregulation.

    Science.gov (United States)

    Tiaden, André N; Bahrenberg, Gregor; Mirsaidi, Ali; Glanz, Stephan; Blüher, Matthias; Richards, Peter J

    2016-06-01

    Adipogenesis is the process by which mesenchymal stem cells (MSCs) develop into lipid-laden adipocytes. Being the dominant cell type within adipose tissue, adipocytes play a central role in regulating circulating fatty acid levels, which is considered to be of critical importance in maintaining insulin sensitivity. High temperature requirement protease A1 (HTRA1) is a newly recognized regulator of MSC differentiation, although its role as a mediator of adipogenesis has not yet been defined. The aim of this work was therefore to evaluate HTRA1's influence on human MSC (hMSC) adipogenesis and to establish a potential mode of action. We report that the addition of exogenous HTRA1 to hMSCs undergoing adipogenesis suppressed their ability to develop into lipid laden adipocytes. These effects were demonstrated as being reliant on both its protease and PDZ domain, and were mediated through the actions of c-Jun N-terminal kinase and matrix metalloproteinases (MMPs). The relevance of such findings with regards to HTRA1's potential influence on adipocyte function in vivo is made evident by the fact that HTRA1 and MMP-13 were readily identifiable within crown-like structures present in visceral adipose tissue samples from insulin resistant obese human subjects. These data therefore implicate HTRA1 as a negative regulator of MSC adipogenesis and are suggestive of its potential involvement in adipose tissue remodeling under pathological conditions. Stem Cells 2016;34:1601-1614. PMID:26864869

  15. Chromatin perturbations during the DNA damage response in higher eukaryotes.

    Science.gov (United States)

    Bakkenist, Christopher J; Kastan, Michael B

    2015-12-01

    The DNA damage response is a widely used term that encompasses all signaling initiated at DNA lesions and damaged replication forks as it extends to orchestrate DNA repair, cell cycle checkpoints, cell death and senescence. ATM, an apical DNA damage signaling kinase, is virtually instantaneously activated following the introduction of DNA double-strand breaks (DSBs). The MRE11-RAD50-NBS1 (MRN) complex, which has a catalytic role in DNA repair, and the KAT5 (Tip60) acetyltransferase are required for maximal ATM kinase activation in cells exposed to low doses of ionizing radiation. The sensing of DNA lesions occurs within a highly complex and heterogeneous chromatin environment. Chromatin decondensation and histone eviction at DSBs may be permissive for KAT5 binding to H3K9me3 and H3K36me3, ATM kinase acetylation and activation. Furthermore, chromatin perturbation may be a prerequisite for most DNA repair. Nucleosome disassembly during DNA repair was first reported in the 1970s by Smerdon and colleagues when nucleosome rearrangement was noted during the process of nucleotide excision repair of UV-induced DNA damage in human cells. Recently, the multi-functional protein nucleolin was identified as the relevant histone chaperone required for partial nucleosome disruption at DBSs, the recruitment of repair enzymes and for DNA repair. Notably, ATM kinase is activated by chromatin perturbations induced by a variety of treatments that do not directly cause DSBs, including treatment with histone deacetylase inhibitors. Central to the mechanisms that activate ATR, the second apical DNA damage signaling kinase, outside of a stalled and collapsed replication fork in S-phase, is chromatin decondensation and histone eviction associated with DNA end resection at DSBs. Thus, a stress that is common to both ATM and ATR kinase activation is chromatin perturbations, and we argue that chromatin perturbations are both sufficient and required for induction of the DNA damage response

  16. Epigenetic Regulation of Cytosolic Phospholipase A2 in SH-SY5Y Human Neuroblastoma Cells.

    Science.gov (United States)

    Tan, Charlene Siew-Hon; Ng, Yee-Kong; Ong, Wei-Yi

    2016-08-01

    Group IVA cytosolic phospholipase A2 (cPLA2 or PLA2G4A) is a key enzyme that contributes to inflammation via the generation of arachidonic acid and eicosanoids. While much is known about regulation of cPLA2 by posttranslational modification such as phosphorylation, little is known about its epigenetic regulation. In this study, treatment with histone deacetylase (HDAC) inhibitors, trichostatin A (TSA), valproic acid, tubacin and the class I HDAC inhibitor, MS-275, were found to increase cPLA2α messenger RNA (mRNA) expression in SH-SY5Y human neuroblastoma cells. Co-treatment of the histone acetyltransferase (HAT) inhibitor, anacardic acid, modulated upregulation of cPLA2α induced by TSA. Specific involvement of class I HDACs and HAT in cPLA2α regulation was further shown, and a Tip60-specific HAT inhibitor, NU9056, modulated the upregulation of cPLA2α induced by MS-275. In addition, co-treatment of with histone methyltransferase (HMT) inhibitor, 5'-deoxy-5'-methylthioadenosine (MTA) suppressed TSA-induced cPLA2α upregulation. The above changes in cPLA2 mRNA expression were reflected at the protein level by Western blots and immunocytochemistry. Chromatin immunoprecipitation (ChIP) showed TSA increased binding of trimethylated H3K4 to the proximal promoter region of the cPLA2α gene. Cell injury after TSA treatment as indicated by lactate dehydrogenase (LDH) release was modulated by anacardic acid, and a role of cPLA2 in mediating TSA-induced injury shown, after co-incubation with the cPLA2 selective inhibitor, arachidonoyl trifluoromethyl ketone (AACOCF3). Together, results indicate epigenetic regulation of cPLA2 and the potential of such regulation for treatment of chronic inflammation. PMID:26162318

  17. Promoter region of interleukin-2 gene undergoes chromatin structure changes and confers inducibility on chloramphenicol acetyltransferase gene during activation of T cells.

    OpenAIRE

    Siebenlist, U; Durand, D B; Bressler, P; Holbrook, N J; Norris, C A; Kamoun, M.; Kant, J A; Crabtree, G R

    1986-01-01

    The chromatin structure of the interleukin-2 (IL-2) gene was probed by DNase I treatment of isolated nuclei. The 5' region of the IL-2 gene contains three regions of hypersensitivity to DNase I. When peripheral blood T cells or Jurkat T cells are stimulated with mitogens, IL-2 message is induced, and the promoter region of the IL-2 gene develops an additional hypersensitive site. This suggests that a DNA sequence close to the transcriptional start site is involved in the transduction of the e...

  18. Common polymorphisms in the microsomal epoxide hydrolase and N-acetyltransferase 2 genes in association with inflammatory bowel disease in the Danish population

    DEFF Research Database (Denmark)

    Ernst, Anja; Andersen, Vibeke; Ostergaard, Mette;

    2011-01-01

    Chronic inflammatory bowel disease (IBD) is characterized by recurrent inflammation of the intestinal mucosa. Reactive molecules play a central role in altering the intestinal permeability, which may induce or sustain an immune response. Changes in detoxification of substances that causes...

  19. Structure and Active Stie Residues of Pg1D, an N-Acetyltransferase from the Bacillosamine Synthetic Pathway Required for N-Glycan Synthesis in Campylobacter jejuni

    Energy Technology Data Exchange (ETDEWEB)

    Rangarajan,E.; Ruane, K.; Sulea, T.; Watson, D.; Proteau, A.; Leclerc, S.; Cygler, M.; Matte, A.; Young, N.

    2008-01-01

    Campylobacter jejuni is highly unusual among bacteria in forming N-linked glycoproteins. The heptasaccharide produced by its pgl system is attached to protein Asn through its terminal 2, 4-diacetamido-2, 4,6-trideoxy-d-Glc (QuiNAc4NAc or N, N'-diacetylbacillosamine) moiety. The crucial, last part of this sugar's synthesis is the acetylation of UDP-2-acetamido-4-amino-2, 4,6-trideoxy-d-Glc by the enzyme PglD, with acetyl-CoA as a cosubstrate. We have determined the crystal structures of PglD in CoA-bound and unbound forms, refined to 1.8 and 1.75 Angstroms resolution, respectively. PglD is a trimer of subunits each comprised of two domains, an N-terminal {alpha}/{beta}-domain and a C-terminal left-handed {beta}-helix. Few structural differences accompany CoA binding, except in the C-terminal region following the {beta}-helix (residues 189-195), which adopts an extended structure in the unbound form and folds to extend the {beta}-helix upon binding CoA. Computational molecular docking suggests a different mode of nucleotide-sugar binding with respect to the acetyl-CoA donor, with the molecules arranged in an 'L-shape', compared with the 'in-line' orientation in related enzymes. Modeling indicates that the oxyanion intermediate would be stabilized by the NH group of Gly143', with His125' the most likely residue to function as a general base, removing H+ from the amino group prior to nucleophilic attack at the carbonyl carbon of acetyl-CoA. Site-specific mutations of active site residues confirmed the importance of His125', Glu124', and Asn118. We conclude that Asn118 exerts its function by stabilizing the intricate hydrogen bonding network within the active site and that Glu124' may function to increase the pKa of the putative general base, His125'.

  20. Circadian Dynamics of the Cone-Rod Homeobox (CRX) Transcription Factor in the Rat Pineal Gland and Its Role in Regulation of Arylalkylamine N-Acetyltransferase (AANAT)

    DEFF Research Database (Denmark)

    Rohde, Kristian; Rovsing, Louise; Ho, Anthony K;

    2014-01-01

    , which is transferred into daily changes in CRX protein. The study further shows that the sympathetic innervation of the pineal gland controls the Crx rhythm. By use of adenovirus-mediated short hairpin RNA gene knockdown targeting Crx mRNA in primary rat pinealocyte cell culture, we here show...

  1. Molecular Dynamics and Combined QM/MM Studies on the Deactivation of anti-Tubercular Drug Isoniazid by Arylamine N-Acetyltransferases

    Institute of Scientific and Technical Information of China (English)

    乔青安; 马翠华; 宋慧玲; 蔡红兰; 蔡政亭; 冯大诚

    2012-01-01

    Both a molecule dynamic study and a combined quantum mechanics and mole-cule mechanics(QM/MM) study on the acetylating deactivation mechanism of isoniazid were presented.This type of reaction was catalyzed by arylamine N-acetyltransferases(NATs) and the results strongly support a direct acetyl group transfer process rather than a stepwise one.The isoniazid was strictly restrained in proper relative position to accept the acetyl group by a Hydrogen-bond network formed by the residues at the active center.The residues,His110 and Cys70,would be functioned as 'general base' rather than 'general acid'.If all the residues(including H2O molecules) were removed from the system,the activation energy will be increased from 145.1 to 243.3 kJ/mol.The calculations met the experimental data with good agreement.

  2. Nucleotide sequence and genetic analysis of the Azotobacter chroococcum nifUSVWZM gene cluster, including a new gene (nifP) which encodes a serine acetyltransferase.

    OpenAIRE

    Evans, D J; Jones, R; Woodley, P R; Wilborn, J R; Robson, R.L.

    1991-01-01

    Nucleotide sequence was obtained for a region of 7,099 bp spanning the nifU, nifS, nifV, nifW, nifZ, and nifM genes from Azotobacter chroococcum. Chromosomal mutations constructed at several sites within the locus confirmed a requirement for this region for expression of the molybdenum nitrogenase in this organism. The genes are tightly clustered and ordered as in Klebsiella pneumoniae except for two additional open reading frames (ORFs) between nifV and nifW. The arrangement of genes in A. c...

  3. Premarin improves memory, prevents scopolamine-induced amnesia and increases number of basal forebrain choline acetyltransferase positive cells in middle-aged surgically menopausal rats

    OpenAIRE

    Acosta, Jazmin I.; Mayer, Loretta; Talboom, Joshua S.; Zay, Cynthia; Scheldrup, Melissa; Castillo, Jonathan; Demers, Laurence M.; Enders, Craig K.; Bimonte-Nelson, Heather A.

    2008-01-01

    Conjugated equine estrogen (CEE) is the most commonly prescribed estrogen therapy, and is the estrogen used in the Women's Health Initiative study. While in-vitro studies suggest that CEE is neuroprotective, no study has evaluated CEE's effects on a cognitive battery and brain immunohistochemistry in an animal model. The current experiment tested whether CEE impacted: I) spatial learning, reference memory, working memory and long-term retention, as well as ability to handle mnemonic delay and...

  4. Structural and Functional Characterization of the TRI101 Trichothecene 3-O-Acetyltransferase from Fusarium sporotrichioides and Fusarium graminearum: KINETIC INSIGHTS TO COMBATING FUSARIUM HEAD BLIGHT

    Energy Technology Data Exchange (ETDEWEB)

    Garvey, Graeme S.; McCormick, Susan P.; Rayment, Ivan (UWASH); (UW); (NCAUR)

    2008-06-30

    Fusarium head blight (FHB) is a plant disease with serious economic and health impacts. It is caused by fungal species belonging to the genus Fusarium and the mycotoxins they produce. Although it has proved difficult to combat this disease, one strategy that has been examined is the introduction of an indigenous fungal protective gene into cereals such as wheat barley and rice. Thus far the gene of choice has been tri101 whose gene product catalyzes the transfer of an acetyl group from acetyl coenzyme A to the C3 hydroxyl moiety of several trichothecene mycotoxins. In vitro this has been shown to reduce the toxicity of the toxins by {approx}100-fold but has demonstrated limited resistance to FHB in transgenic cereal. To understand the molecular basis for the differences between in vitro and in vivo resistance the three-dimensional structures and kinetic properties of two TRI101 orthologs isolated from Fusarium sporotrichioides and Fusarium graminearum have been determined. The kinetic results reveal important differences in activity of these enzymes toward B-type trichothecenes such as deoxynivalenol. These differences in activity can be explained in part by the three-dimensional structures for the ternary complexes for both of these enzymes with coenzyme A and trichothecene mycotoxins. The structural and kinetic results together emphasize that the choice of an enzymatic resistance gene in transgenic crop protection strategies must take into account the kinetic profile of the selected protein.

  5. Hippocampal cholinergic interneurons visualized with the choline acetyltransferase promoter: anatomical distribution, intrinsic membrane properties, neurochemical characteristics, and capacity for cholinergic modulation

    Directory of Open Access Journals (Sweden)

    Feng eYi

    2015-03-01

    Full Text Available Release of acetylcholine (ACh in the hippocampus (HC occurs during exploration, arousal, and learning. Although the medial septum-diagonal band of Broca (MS-DBB is the major extrinsic source of cholinergic input to the HC, cholinergic neurons intrinsic to the HC also exist but remain poorly understood. Here, ChAT-tauGFP and ChAT-CRE/Rosa26YFP (ChAT-Rosa mice were examined in HC. The HC of ChAT-tauGFP mice was densely innervated with GFP-positive axons, often accompanied by large GFP-positive structures, some of which were Neurotrace/DAPI-negative and likely represent large axon terminals. In the HC of ChAT-Rosa mice, ChAT-YFP cells were Neurotrace-positive and more abundant in CA3 and dentate gyrus than CA1 with partial overlapping with calretinin/VIP. Moreover, an anti-ChAT antibody consistently showed ChAT immunoreactivity in ChAT-YFP cells from MS-DBB but rarely from HC. Furthermore, ChAT-YFP cells from CA1 stratum radiatum/stratum lacunosum moleculare (SR/SLM exhibited a stuttering firing phenotype but a delayed firing phenotype in stratum pyramidale (SP of CA3. Input resistance and capacitance were also different between CA1 SR/LM and CA3 SP ChAT-YFP cells. Bath application of ACh increased firing frequency in all ChAT-YFP cells; however, cholinergic modulation was larger in CA1 SR/SLM than CA3 SP ChAT-YFP cells. Finally, CA3 SP ChAT-YFP cells exhibited a wider AP half-width and weaker cholinergic modulation than YFP-negative CA3 pyramidal cells. Consistent with CRE expression in a subpopulation of principal cells, optogenetic stimulation evoked glutamatergic postsynaptic currents in CA1 SR/SLM interneurons. In conclusion, the presence of fluorescently labeled hippocampal cells common to both ChAT-Rosa and ChAT-tauGFP mice are in good agreement with previous reports on the existence of cholinergic interneurons, but both transgenic mouse lines exhibited unexpected anatomical features that departed considerably from earlier observations.

  6. Adipogenic and energy metabolism gene networks in longissimus lumborum during rapid post-weaning growth in Angus and Angus × Simmental cattle fed high-starch or low-starch diets

    Directory of Open Access Journals (Sweden)

    Graugnard Daniel E

    2009-03-01

    Full Text Available Abstract Background Transcriptional networks coordinate adipocyte differentiation and energy metabolism in rodents. The level of fiber and starch in diets with adequate energy content fed to young cattle has the potential to alter intramuscular adipose tissue development in skeletal muscle. Post-weaning alterations in gene expression networks driving adipogenesis, lipid filling, and intracellular energy metabolism provide a means to evaluate long-term effects of nutrition on longissimus muscle development across cattle types. Results Longissimus lumborum (LL from Angus (n = 6 and Angus × Simmental (A × S; n = 6 steer calves (155 ± 10 days age fed isonitrogenous high-starch (HiS; 1.43 Mcal/kg diet dry matter; n = 6 or low-starch (LoS; 1.19 Mcal/kg diet dry matter; n = 6 diets was biopsied at 0, 56, and 112 days of feeding for transcript profiling of 31 genes associated with aspects of adipogenesis and energy metabolism. Intake of dietary energy (9.44 ± 0.57 Mcal/d across groups during the study did not differ but feed efficiency (weight gain/feed intake during the first 56 days was greater for steers fed HiS. Expression of PPARG increased ca. 2-fold by day 56 primarily due to HiS in A × S steers. Several potential PPARG-target genes (e.g., ACACA, FASN, FABP4, SCD increased 2.5-to-25-fold by day 56 across all groups, with responses (e.g., FASN, FABP4 being less pronounced in A × S steers fed LoS. This latter group of steers had markedly greater blood plasma glucose (0.99 vs. 0.79 g/L and insulin (2.95 vs. 1.17 μg/L by day 112, all of which were suggestive of insulin resistance. Interactions were observed for FABP4, FASN, GPAM, SCD, and DGAT2, such that feeding A × S steers high-starch and Angus steers low-starch resulted in greater fold-changes by day 56 or 112 (GPAM. Marked up-regulation of INSIG1 (4-to-8-fold occurred throughout the study across all groups. SREBF1 expression, however, was only greater on day 112 namely due to LoS in A × S steers. The lipogenic transcription factor THRSP was 6-to-60-fold greater by day 56 primarily due to HiS in A × S steers, constituting the greatest response among all genes. Conclusion Results involving gene markers of mature adipocytes (e.g., PPARG, THRSP, SCD provided evidence of intramuscular adipose tissue differentiation during the early portion of the growing phase. The resulting gene networks underscored a central role for PPARG in controlling transcription of genes which are known to co-ordinately regulate adipocyte differentiation and lipid filling in non-ruminants. Unlike rodents, INSIG1 appears to play an important role in cattle muscle adipogenesis. We propose that a network of transcription regulators and nuclear receptors including PPARG-target genes, INSIG1, and THRSP, coordinate activation of adipocyte differentiation and lipid filling at an early age.

  7. Centipede grass exerts anti-adipogenic activity through inhibition of C/EBPβ, C/EBPα, and PPARγ expression and the AKT signaling pathway in 3T3-L1 adipocytes

    Directory of Open Access Journals (Sweden)

    Park Hyoung Joon

    2012-11-01

    Full Text Available Abstract Background Centipede grass (CG originates from China and South America and is reported to contain several C-glycosyl flavones and phenolic constituents, including maysin and luteolin derivatives. This study aimed to investigate, for the first time, the antiobesity activity of CG and its potential molecular mechanism in 3T3-L1 cells. Methods To study the effect of CG on adipogenesis, differentiating 3T3-L1 cells were treated every day with CG at various concentrations (0–100 μg/ml for six days. Oil-red O staining and triglyceride content assay were performed to determine the lipid accumulation in 3T3-L1 cells. The expression of mRNAs or proteins associated with adipogenesis was measured using RT-PCR and Western blotting analysis. We examined the effect of CG on level of phosphorylated Akt in 3T3-L1 cells treated with CG at various concentration s during adipocyte differentiation. Results Differentiation was investigated with an Oil-red O staining assay using CG-treated 3T3-L1 adipocytes. We found that CG suppressed lipid droplet formation and adipocyte differentiation in 3T3-L1 cells in a dose-dependent manner. Treatment of the 3T3-L1 adipocytes with CG resulted in an attenuation of the expression of adipogenesis-related factors and lipid metabolic genes. The expression of C/EBPα and PPARγ, the central transcriptional regulators of adipogenesis, was decreased by the treatment with CG. The expression of genes involved in lipid metabolism, aP2 were significantly inhibited following the CG treatment. Moreover, the CG treatment down-regulated the phosphorylation levels of Akt and GSK3β. Conclusions Taken collectively, these data indicated that CG exerts antiadipogenic activity by inhibiting the expression of C/EBPβ, C/EBPα, and PPARγ and the Akt signaling pathway in 3T3-L1 adipocytes.

  8. Buckwheat (Fagopyrum esculentum M.) Sprout Treated with Methyl Jasmonate (MeJA) Improved Anti-Adipogenic Activity Associated with the Oxidative Stress System in 3T3-L1 Adipocytes

    OpenAIRE

    Jeong-Ho Lim; Kee-Jai Park; Bo-Ra Yoon; Kui-Jin Kim; Young-Jun Lee; Ok-Hwan Lee

    2013-01-01

    Buckwheat sprouts contain various bioactive compounds including rutin which have a number of biological activities. We have previously shown that buckwheat sprouts (TBWE) treated with methyl jasmonate (MeJA) significantly increased the amount of phenolics and the antioxidant activity. The aim of this study was to demonstrate the effect of TBWE on anti-adipogenesis and pro-oxidant enzyme in 3T3-L1 adipocytes. We also evaluated the anti-oxidative activity of TBWE in adipocytes by using the nitr...

  9. Differential effects of garcinol and curcumin on histone and p53 modifications in tumour cells

    International Nuclear Information System (INIS)

    Post-translational modifications (PTMs) of histones and other proteins are perturbed in tumours. For example, reduced levels of acetylated H4K16 and trimethylated H4K20 are associated with high tumour grade and poor survival in breast cancer. Drug-like molecules that can reprogram selected histone PTMs in tumour cells are therefore of interest as potential cancer chemopreventive agents. In this study we assessed the effects of the phytocompounds garcinol and curcumin on histone and p53 modification in cancer cells, focussing on the breast tumour cell line MCF7. Cell viability/proliferation assays, cell cycle analysis by flow cytometry, immunodetection of specific histone and p53 acetylation marks, western blotting, siRNA and RT-qPCR. Although treatment with curcumin, garcinol or the garcinol derivative LTK-14 hampered MCF7 cell proliferation, differential effects of these compounds on histone modifications were observed. Garcinol treatment resulted in a strong reduction in H3K18 acetylation, which is required for S phase progression. Similar effects of garcinol on H3K18 acetylation were observed in the osteosarcoma cells lines U2OS and SaOS2. In contrast, global levels of acetylated H4K16 and trimethylated H4K20 in MCF7 cells were elevated after garcinol treatment. This was accompanied by upregulation of DNA damage signalling markers such as γH2A.X, H3K56Ac, p53 and TIP60. In contrast, exposure of MCF7 cells to curcumin resulted in increased global levels of acetylated H3K18 and H4K16, and was less effective in inducing DNA damage markers. In addition to its effects on histone modifications, garcinol was found to block CBP/p300-mediated acetylation of the C-terminal activation domain of p53, but resulted in enhanced acetylation of p53K120, and accumulation of p53 in the cytoplasmic compartment. Finally, we show that the elevation of H4K20Me3 levels by garcinol correlated with increased expression of SUV420H2, and was prevented by siRNA targeting of SUV420H2. In

  10. NCBI nr-aa BLAST: CBRC-DSIM-04-0033 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DSIM-04-0033 gb|AAL05995.1|AF401528_12 putative acetyltransferase [Campylobacter... jejuni] gb|AAZ80467.1| putative acetyltransferase [Campylobacter jejuni] gb|ABC79677.1| putative acetyltransferase [Campylobacter jejuni] AAL05995.1 5.6 41% ...

  11. The inhibition of inflammatory molecule expression on 3T3-L1 adipocytes by berberine is not mediated by leptin signaling

    OpenAIRE

    Choi, Bong-Hyuk; Kim, Yu-Hee; Ahn, In-Sook; Ha, Jung-Heun; Byun, Jae-Min; Do, Myoung-Sool

    2009-01-01

    In our previous study, we have shown that berberine has both anti-adipogenic and anti-inflammatory effects on 3T3-L1 adipocytes, and the anti-adipogenic effect is due to the down-regulation of adipogenic enzymes and transcription factors. Here we focused more on anti-inflammatory effect of berberine using real time RT-PCR and found it changes expressions of adipokines. We hypothesized that anti-adipogenicity of berberine mediates anti-inflammtory effect and explored leptin as a candidate medi...

  12. 转录辅激活因子和乙酰基转移酶p300在心肌肥厚中的作用%Role of the transcriptional coactivator and acetyltransferase p300 in cardiac hypertrophy

    Institute of Scientific and Technical Information of China (English)

    饶芳; 韦鉴钦

    2014-01-01

    心肌细胞中,p300是维持其分化表型所必须的转录辅激活因子.在心脏压力负荷增加等病理条件下,一些肥厚反应转录因子,如锌指蛋白GATA-4和肌细胞增强因子2(MEF2)等,可与p300相互作用,参与心肌细胞肥厚的病理过程.拮抗p300可有效阻断心肌肥厚的病理进程,进而改善心功能.更好地了解p300在心肌肥厚中的作用,对于未来治疗心肌肥厚和心力衰竭具有重要意义.

  13. 龙葵碱对人肝癌HepG2细胞N-乙酰基转移酶活性的影响%Effect of solanine on N-acetyltransferase activity in HepG2 cell

    Institute of Scientific and Technical Information of China (English)

    高世勇; 季字彬

    2008-01-01

    目的 探讨龙葵碱对HepG2细胞Ⅳ-乙酰基转移酶(NAT)活性的影响.方法 采用HPLC方法,以2-氨基芴(2-AF)为底物,以2-AF被NAT乙酰化为2-乙酰氨基芴(2-AAF)的量来反应NAT的活性.结果 龙葵碱能显著降低HepG2完整细胞NAT的活性;龙葵碱能够降低HepG2细胞质内NAT的活性,作用具有剂量依赖性.结论 龙葵碱通过抑制HepG2细胞NAT的活性发挥细胞毒作用.

  14. Detection of aminoglycoside acetyltransferases in Acinetobacter baumannii by multiplex PCR%多重PCR检测鲍曼不动杆菌氨基糖苷乙酰转移酶相关基因

    Institute of Scientific and Technical Information of China (English)

    刘丁; 陈萍; 李玉红; 杨程

    2006-01-01

    目的 分析aac耐药基因亚型在临床分离的耐氨基糖苷类鲍曼不动杆菌中的检出情况,建立检测鲍曼不动杆菌耐药性的分子生物学方法.方法 对从临床分离的42株鲍曼不动杆菌,进行药敏试验同时行aac耐药基因PCR检测.结果 本地区所分离的鲍曼不动杆菌对庆大霉素耐药率最高(57%),对丁胺卡那耐药率较低(29%).在对妥布霉素、庆大霉素、丁胺卡那至少一种耐药的鲍曼不动杆菌中,除2株细菌外,均检测到乙酰转移酶基因,其中6株有aac(6')-Ih、20株为aac(3)-Ia、14株含aac(6')-Ib、14株同时含aac(3)-Ia和aac(6')-Ib.结论 本地区鲍曼不动杆菌对临床常用氨基糖苷类抗生素庆大霉素耐药率高,其耐药主要是由aac(3)-Ia、aac(6')-Ib编码的酶引起.

  15. Ligand-controlled interaction of histone acetyltransferase binding to ORC-1 (HBO1) with the N-terminal transactivating domain of progesterone receptor induces steroid receptor coactivator 1-dependent coactivation of transcription

    NARCIS (Netherlands)

    M. Georgiakaki (Maria); L.J. Blok (Leen); R. Milgrom (Roni); M. Lombès (Marc); A. Guiochon-Mantel (Anne); H. Loosfelt (Hugues); N. Chabbert-Buffet (Nathalie); B. Dasen (Boris); G. Meduri (Geri); S. Wenk (Sandra); L. Rajhi (Leila); L. Amazit (Larbi); A. Chauchereau (Anne); C.W. Burger (Curt)

    2006-01-01

    textabstractModulators of cofactor recruitment by nuclear receptors are expected to play an important role in the coordination of hormone-induced transactivation processes. To identify such factors interacting with the N-terminal domain (NTD) of the progesterone receptor (PR), we used this domain as

  16. Role of histone acetyltransferase MOF in the pathogenesis of multiple sclerosis%组蛋白乙酰转移酶 MOF 在多发性硬化发病机制中的作用

    Institute of Scientific and Technical Information of China (English)

    关景云; 杨阳; 邱春红; 李相芝

    2016-01-01

    目的:探讨实验性自身免疫性脑脊髓炎(EAE)小鼠发病高峰期、缓解期 Treg 细胞和组蛋白乙酰转移酶MOF 表达的变化情况,以及 MOF 对 EAE 发病机制的影响。方法将20只体质量相近的6~8周龄 C57BL/6雌鼠随机分为两组,EAE 组第0天腹股沟处皮下注射200μg MOG35-55,对照组注射等量弗氏完全佐剂,两组均腹腔注射200 ng百日咳毒素,第2天腹腔注射200 ng 百日咳毒素。取 EAE 组不同发病时期和对照组小鼠的脾脏组织。Western blotting 法检测 MOF、FOXP3和 H4K16ac 蛋白的表达情况;qRT-PCR 检测脾脏组织中 MOF、FOXP3、TLRS mRNA 的表达水平;蛋白质免疫共沉淀(CoIP)法检测 MOF 与 FOXP3在脾脏组织中有无相互作用;染色质免疫共沉淀(ChIP-qPCR)法检测 MOF 的下游靶基因;在 HCT116细胞中过表达 MOF 后检测 FOXP3、TLRS 表达的变化情况。结果EAE 组脾脏中的 MOF 及 FOXP3蛋白表达水平显著高于对照组;EAE 组小鼠脾脏中 MOF、FOXP3、IL17、TLR4、TLR5、TLR6、TLR7、TLR9 mRNA 水平显著高于对照组(P <0.05);MOF 与 FOXP3在脾脏组织中结合并有相互作用;脾脏组织中,MOF 与 FOXP3、TLR3、TLR4、TLR5、TLR6、SMAD2、SMAD3和 RoRγt 启动子结合;MOF过表达后,TLR4和 FOXP3表达量增加(P <0.05)。结论MOF 通过与 FOXP3相互作用,抑制 EAE 的发生。%Objective To investigate the activities of Treg cells and the expression of MOF in the peak and remission periods of experimental allergic encephalomyelitis(EAE)mice and the impact of MOF on the pathogenesis of EAE. Methods On Day 0,twenty 6-8 week old C57BL/6 female mice of similar weight were subcutaneously injected with 200 μg MOG35-55 or complete freund’s adjuvant (CFA)and then intraperitoneally injected with 200 ng pertussis toxin. On Day 2,the above three mice were intraperitoneally injected with 200 ng pertussis toxin.The spleen tissues of the EAE mice in different phases were used,along with the spleen tissues of the mice from control group in the same pha-ses.The protein levels of MOF,FOXP3,and H4K16ac were detected through Western blotting.The mRNA expression levels of MOF,TLRS,and FOXP3 were detected by real-time fluorescent quantitative RT-PCR.Co-immunoprecipitati-on was performed to assess the binding between MOF and FOXP3 in the spleen tissues.ChIP-qPCR was performed to detect the downstream target genes of MOF.The relationships between the protein expression levels of TLRS,FOXP3 in the HCT116 cells,and MOF regulation were also studied.Results The expression levels of MOF and FOXP3 pro-tein in the spleen of EAE mice were significantly higher than those of the control group.The mRNA levels of FOXP3, MOF,IL17,TLR4,TLR5,TLR6,TLR7 and TLR9 in EAE mouse spleen tissue were significantly higher than those of the control group(P <0.05);Co-IP showed that MOF directly interacted with FOXP3 in spleen tissues;ChIP-qPCR showed that MOF combined with FOXP3,TLR3,TLR4,TLR5,TLR6,SMAD2,SMAD3,and RoRγt genes in the spleen.TLR4 and FOXP3 showed higher expression levels in the HCT116 cells compared with the control group when MOF was overexpressed(P <0.05).Conclusion MOF suppresses the occurrence of EAE through its interaction with FOXP3.

  17. Histone deacetylase inhibitors modulate the transcriptional regulation of guanylyl cyclase/natriuretic peptide receptor-a gene: interactive roles of modified histones, histone acetyltransferase, p300, AND Sp1.

    Science.gov (United States)

    Kumar, Prerna; Tripathi, Satyabha; Pandey, Kailash N

    2014-03-01

    Atrial natriuretic peptide (ANP) binds guanylyl cyclase-A/natriuretic peptide receptor-A (GC-A/NPRA) and produces the intracellular second messenger, cGMP, which regulates cardiovascular homeostasis. We sought to determine the function of histone deacetylases (HDACs) in regulating Npr1 (coding for GC-A/NPRA) gene transcription, using primary mouse mesangial cells treated with class-specific HDAC inhibitors (HDACi). Trichostatin A, a pan inhibitor, and mocetinostat (MGCD0103), a class I HDAC inhibitor, significantly enhanced Npr1 promoter activity (by 8- and 10-fold, respectively), mRNA levels (4- and 5.3-fold, respectively), and NPRA protein (2.7- and 3.5-fold, respectively). However, MC1568 (class II HDAC inhibitor) had no discernible effect. Overexpression of HDAC1 and HDAC2 significantly attenuated Npr1 promoter activity, whereas HDAC3 and HDAC8 had no effect. HDACi-treated cultured cells in vitro and intact animals in vivo showed significantly reduced binding of HDAC1 and -2 and increased accumulation of acetylated H3-K9/14 and H4-K12 at the Npr1 promoter. Deletional analyses of the Npr1 promoter along with ectopic overexpression and inhibition of Sp1 confirmed that HDACi-induced Npr1 gene transcription is accomplished by Sp1 activation. Furthermore, HDACi attenuated the interaction of Sp1 with HDAC1/2 and promoted Sp1 association with p300 and p300/cAMP-binding protein-associated factor; it also promoted the recruitment of p300 and p300/cAMP-binding protein-associated factor to the Npr1 promoter. Our results demonstrate that trichostatin A and MGCD0103 enhanced Npr1 gene expression through inhibition of HDAC1/2 and increased both acetylation of histones (H3-K9/14, H4-K12) and Sp1 by p300, and their recruitment to Npr1 promoter. Our findings define a novel epigenetic regulatory mechanism that governs Npr1 gene transcription.

  18. The influence of thiazolidinediones on marbling in pigs: in vitro studies of muscle stromal-vascular cells from fetal and young pigs and in vivo studies of growing pigs

    Science.gov (United States)

    Thiazolidinediones (TZDs) are insulin sensitizing agents currently used for the treatment of type 2 diabetes and are widely used as adipogenic agents since they are ligands of PPAR', a key adipogenic transcription factor. In vitro studies of porcine S-V cells from semitendinosus muscles and adipose ...

  19. The anti-obesity effects of a tuna peptide on 3T3-L1 adipocytes are mediated by the inhibition of the expression of lipogenic and adipogenic genes and by the activation of the Wnt/β-catenin signaling pathway

    Science.gov (United States)

    KIM, YOUNG-MIN; KIM, IN-HYE; CHOI, JEONG-WOOK; LEE, MIN-KYEONG; NAM, TAEK-JEONG

    2015-01-01

    The differentiation of 3T3-L1 cells into adipocytes involves the activation of an organized system of obesity-related genes, of which those encoding CCAAT/enhancer-binding proteins (C/EBPs) and the Wnt-10b protein may play integral roles. In a previous study of ours, we found that a specific peptide found in tuna (sequence D-I-V-D-K-I-E-I; termed TP-D) inhibited 3T3-L1 cell differentiation. In the present study, we observed that the expression of expression of C/EBPs and Wnt-10b was associated with obesity. The initial step of 3T3-L1 cell differentiation involved the upregulation of C/EBP-α expression, which in turn activated various subfactors. An upstream effector of glycogen synthase kinase-3β (GSK-3β) inhibited Wnt-10b expression in 3T3-L1 adipocytes. In a previous study of ours, we sequenced the tuna peptide via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and quadrupole time-of-flight mass spectrometry (Q-TOF MS/MS) and confirmed the anti-obesity effects thereof in 3T3-L1 adipocytes. In the present study, we demonstrate that TP-D inhibits C/EBP and promotes Wnt-10b mRNA expression, thus activating the Wnt pathway. The inhibition of lipid accumulation was measured using a glucose and triglyceride (TG) assay. Our results confirmed that TP-D altered the expression levels of C/EBP-related genes in a dose-dependent manner and activated the Wnt signaling pathway. In addition, we confirmed that total adiponectin and high-molecular weight (HMW) adiponectin levels were reduced by treatment with TP-D. These data indicate that TP-D inhibits adipocyte differentiation through the inhibition of C/EBP genes and the subsequent activation of the Wnt/β-catenin signaling pathway. PMID:26046125

  20. The anti-obesity effects of a tuna peptide on 3T3-L1 adipocytes are mediated by the inhibition of the expression of lipogenic and adipogenic genes and by the activation of the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Kim, Young-Min; Kim, In-Hye; Choi, Jeong-Wook; Lee, Min-Kyeong; Nam, Taek-Jeong

    2015-08-01

    The differentiation of 3T3-L1 cells into adipocytes involves the activation of an organized system of obesity-related genes, of which those encoding CCAAT/enhancer-binding proteins (C/EBPs) and the Wnt-10b protein may play integral roles. In a previous study of ours, we found that a specific peptide found in tuna (sequence D-I-V-D-K-I-E-I; termed TP-D) inhibited 3T3-L1 cell differentiation. In the present study, we observed that the expression of expression of C/EBPs and Wnt-10b was associated with obesity. The initial step of 3T3-L1 cell differentiation involved the upregulation of C/EBP-α expression, which in turn activated various subfactors. An upstream effector of glycogen synthase kinase-3β (GSK-3β) inhibited Wnt-10b expression in 3T3-L1 adipocytes. In a previous study of ours, we sequenced the tuna peptide via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and quadrupole time-of-flight mass spectrometry (Q-TOF MS/MS) and confirmed the anti-obesity effects thereof in 3T3-L1 adipocytes. In the present study, we demonstrate that TP-D inhibits C/EBP and promotes Wnt-10b mRNA expression, thus activating the Wnt pathway. The inhibition of lipid accumulation was measured using a glucose and triglyceride (TG) assay. Our results confirmed that TP-D altered the expression levels of C/EBP-related genes in a dose-dependent manner and activated the Wnt signaling pathway. In addition, we confirmed that total adiponectin and high-molecular weight (HMW) adiponectin levels were reduced by treatment with TP-D. These data indicate that TP-D inhibits adipocyte differentiation through the inhibition of C/EBP genes and the subsequent activation of the Wnt/β-catenin signaling pathway.

  1. Inhibition of Adipocyte Differentiation by Phytoestrogen Genistein Through a Potential Downregulation of Extracellular Signal-Regulated Kinases 1/2 Activity

    Science.gov (United States)

    Liao, Qing-Chuan; Li, Ya-Lin; Qin, Yan-Fang; Quarles, L. Darryl; Xu, Kang-Kang; Li, Rong; Zhou, Hong-Hao; Xiao, Zhou-Sheng

    2016-01-01

    In the current study, we investigated the effects of genistein on adipogenic differentiation of mouse bone marrow-derived mesenchymal stem cell (BMSC) cultures and its potential signaling pathway. The terminal adipogenic differentiation was assessed by western-blotting analysis of adipogenic-specific proteins such as PPARγ, C/EBPα, and aP2 and the formation of adipocytes. Treatment of mouse BMSC cultures with adipogenic cocktail resulted in sustained activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), which are members of the mitogen-activated protein kinase (MAPK) family, at the early phase of adipogenesis (from days 3 to 9). Inhibition of ERK1/2 activation by PD98059, a specific MEK inhibitor, reversed the induced adipogenic differentiation. Genistein dose-dependently decreased the phosphorylation of ERK1/2 in mouse BMSC cultures. Genistein incubation for the entire culture period, as well as that applied during the early phase of the culture period, significantly inhibited the adipogenic differentiation of mouse BMSC cultures. While genistein was incubated at the late stage (after day 9), no inhibitory effect on adipogenic differentiation was observed. BMSC cultures treated with genistein in the presence of fibroblast growth factor-2 (FGF-2), an activator of the ERK1/2 signaling pathway, expressed normal levels of ERK1/2 activity, and, in so doing, are capable of undergoing adipogenesis. Our results suggest that activation of the ERK1/2 signaling pathway during the early phase of adipogenesis (from days 3 to 9) is essential to adipogenic differentiation of BMSC cultures, and that genistein inhibits the adipogenic differentiation through a potential downregulation of ERK1/2 activity at this early phase of adipogenesis. PMID:18384126

  2. Characterization of the biosynthesis, processing and kinetic mechanism of action of the enzyme deficient in mucopolysaccharidosis IIIC.

    Directory of Open Access Journals (Sweden)

    Xiaolian Fan

    Full Text Available Heparin acetyl-CoA:alpha-glucosaminide N-acetyltransferase (N-acetyltransferase, EC 2.3.1.78 is an integral lysosomal membrane protein containing 11 transmembrane domains, encoded by the HGSNAT gene. Deficiencies of N-acetyltransferase lead to mucopolysaccharidosis IIIC. We demonstrate that contrary to a previous report, the N-acetyltransferase signal peptide is co-translationally cleaved and that this event is required for its intracellular transport to the lysosome. While we confirm that the N-acetyltransferase precursor polypeptide is processed in the lysosome into a small amino-terminal alpha- and a larger ß- chain, we further characterize this event by identifying the mature amino-terminus of each chain. We also demonstrate this processing step(s is not, as previously reported, needed to produce a functional transferase, i.e., the precursor is active. We next optimize the biochemical assay procedure so that it remains linear as N-acetyltransferase is purified or protein-extracts containing N-acetyltransferase are diluted, by the inclusion of negatively charged lipids. We then use this assay to demonstrate that the purified single N-acetyltransferase protein is both necessary and sufficient to express transferase activity, and that N-acetyltransferase functions as a monomer. Finally, the kinetic mechanism of action of purified N-acetyltransferase was evaluated and found to be a random sequential mechanism involving the formation of a ternary complex with its two substrates; i.e., N-acetyltransferase does not operate through a ping-pong mechanism as previously reported. We confirm this conclusion by demonstrating experimentally that no acetylated enzyme intermediate is formed during the reaction.

  3. NCBI nr-aa BLAST: CBRC-OLAT-26-0102 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OLAT-26-0102 ref|YP_782770.1| phosphate acetyltransferase [Rhodopseudomonas pa...lustris BisA53] gb|ABJ07790.1| phosphate acetyltransferase [Rhodopseudomonas palustris BisA53] YP_782770.1 0.040 30% ...

  4. Silibinin Regulates Lipid Metabolism and Differentiation in Functional Human Adipocytes

    OpenAIRE

    Barbagallo, Ignazio; Vanella, Luca; Cambria, Maria T.; Tibullo, Daniele; Godos, Justyna; Guarnaccia, Laura; Zappalà, Agata; Galvano, Fabio; Li Volti, Giovanni

    2016-01-01

    Silibinin, a natural plant flavonolignan is the main active constituent found in milk thistle (Silybum marianum). It is known to have hepatoprotective, anti-neoplastic effect, and suppresses lipid accumulation in adipocytes. Objective of this study was to investigate the effect of silibinin on adipogenic differentiation and thermogenic capacity of human adipose tissue derived mesenchymal stem cells. Silibinin (10 μM) treatment, either at the beginning or at the end of adipogenic differentiati...

  5. Baicalein inhibits lipid accumulation by regulating early adipogenesis and m-TOR signaling.

    Science.gov (United States)

    Seo, Min-Jung; Choi, Hyeon-Son; Jeon, Hui-Jeon; Woo, Mi-Seon; Lee, Boo-Yong

    2014-05-01

    Baicalein is a type of flavonoid that originates from Scutellaria baicalensis. In this study, we examined how baicalein inhibits lipid accumulation during adipogenesis in 3T3-L1 cells. Our data show that baicalein inhibited lipid accumulation during adipogenesis in a dose-dependent manner. Baicalein inhibition was limited to the early adipogenic stage. Cell cycle analysis showed that baicalein induced cell cycle arrest in the G0/G1 phase through cyclin downregulation. In addition, baicalein suppressed the mRNA expression of early adipogenic factors leading to downregulation of late adipogenic factors at mRNA and protein levels. Inhibition of adipogenic factors by baicalein was correlated with downregulation of lipid synthetic enzymes. Additionally, baicalein negatively regulated the m-TOR signaling pathway involved in lipid accumulation during adipogenesis, thus inhibiting phosphorylation of m-TOR and p70S6K. In a zebrafish study, baicalein significantly reduced lipid accumulation in Nile Red staining. Consistent with a report using cell lines, mRNA expression of adipogenic factors was decreased in a dose-dependent manner by baicalein. This result reflects a reduction in total triglyceride levels based on a triglyceride assay. Our data suggest that baicalein inhibits lipid accumulation by controlling the cell cycle and m-TOR signaling in 3T3-L1 cells, and its anti-adipogenic effect was found in a zebrafish model.

  6. The Antiaging Gene Klotho Regulates Proliferation and Differentiation of Adipose-Derived Stem Cells.

    Science.gov (United States)

    Fan, Jun; Sun, Zhongjie

    2016-06-01

    Klotho was originally discovered as an aging-suppressor gene. The purpose of this study was to investigate whether secreted Klotho (SKL) affects the proliferation and differentiation of adipose-derived stem cells (ADSCs). RT-PCR and Western blot analysis showed that short-form Klotho was expressed in mouse ADSCs. The Klotho gene mutation KL(-/-) significantly decreased proliferation of ADSCs and expression of pluripotent transcription factors (Nanog, Sox-2, and Oct-4) in mice. The adipogenic differentiation of ADSCs was also decreased in KL(-/-) mice. Incubation with Klotho-deficient medium decreased ADSC proliferation, pluripotent transcription factor levels, and adipogenic differentiation, which is similar to what was found in KL(-/-) mice. These results indicate that Klotho deficiency suppresses ADSC proliferation and differentiation. Interestingly, treatment with recombinant SKL protein rescued the Klotho deficiency-induced impairment in ADSC proliferation and adipogenic differentiation. SKL also regulated ADSCs' differentiation to other cell lineages (osteoblasts, myofibroblasts), indicating that SKL maintains stemness of ADSCs. It is intriguing that overexpression of SKL significantly increased PPAR-γ expression and lipid formation in ADSCs following adipogenic induction, indicating enhanced adipogenic differentiation. Overexpression of SKL inhibited expression of TGFβ1 and its downstream signaling mediator Smad2/3. This study demonstrates, for the first time, that SKL is essential to the maintenance of normal proliferation and differentiation in ADSCs. Klotho regulates adipogenic differentiation in ADSCs, likely via inhibition of TGFβ1 and activation of PPAR-γ. Stem Cells 2016;34:1615-1625. PMID:26865060

  7. Cysteine dioxygenase type 1 promotes adipogenesis via interaction with peroxisome proliferator-activated receptor gamma

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Peng; Chen, Yi; Ji, Ning; Lin, Yunfeng; Yuan, Quan; Ye, Ling; Chen, Qianming, E-mail: qmchen@scu.edu.cn

    2015-02-27

    Mammalian cysteine dioxygenase type 1 (CDO1) is an essential enzyme for taurine biosynthesis and the biodegradation of toxic cysteine. As previously suggested, Cdo1 may be a marker of liposarcoma progression and adipogenic differentiation, but the role of Cdo1 in adipogenesis has yet been reported. In this study, we found that the expression of Cdo1 is dramatically elevated during adipogenic differentiation of 3T3-L1 pre-adipocytes and mouse bone marrow-derived mesenchymal stem cells (mBMSCs). Conversely, knockdown of Cdo1 inhibited expression of adipogenic specific genes and lipid droplet formation in 3T3-L1 cells and mBMSCs. Mechanistically, we found Cdo1 interacted with Pparγ in response to adipogenic stimulus. Further, depletion of Cdo1 reduced the recruitment of Pparγ to the promoters of C/EBPα and Fabp4. Collectively, our finding indicates that Cdo1 may be a co-activator of Pparγ in adipogenesis, and may contribute to the development of disease associated with excessive adipose tissue. - Highlights: • Cdo1expression is highly up-regulated during adipogenic differentiation of 3T3-L1 and mBMSCs. • Depletion of Cdo1 inhibited expression of adipogenic specific genes and lipid droplet formation. • Cdo1interacts with Pparγ during adipogenesis. • Knockdown of Cdo1 inhibited Pparγ binding to the promoters of C/EBPα and Fabp4.