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Sample records for cellular retinol-binding protein

  1. Essential dynamics of the cellular retinol-binding protein - Evidence for ligand-induced conformational changes

    NARCIS (Netherlands)

    van Aalten, D.M.F.; Findlay, J.B.C.; Amadei, A; Berendsen, H.J.C.

    1995-01-01

    The cellular retinol-binding protein (CRBP) is an intracellular retinol carrier protein belonging to a family of hydrophobic ligand-binding proteins, It transports retinol to specific locations in the cell where, for instance, it is esterified for storage, Recently solved crystallographic structures

  2. Epigenetic Silencing of Cellular Retinol-Binding Proteins in Nasopharyngeal Carcinoma

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    Joseph Kwong

    2005-01-01

    Full Text Available Aberrant retinoid signaling in human cancers is extending from the nucleus to the cytoplasm. Recently, we have demonstrated frequent epigenetic inactivation of a retinoic acid receptor (RAR, RARβ2, in nasopharyngeal carcinoma (NPC. To further explore targets contributing to aberrant retinoid signaling in NPC, the expression of cellular retinol-binding proteins (CRBPs, cellular retinoic acid-binding proteins (CRABPs, RARs, and retinoid X receptors (RXRs was examined. Apart from RARβ2, transcriptional silencing of two CRBPs, CRBPI and CRBPIV, was observed in NPC cell lines and xenografts. Hypermethylation of CRBPI and CRBPIV CpG islands was found to be closely correlated with the loss of expression. Treatment with the DNA methyltransferase inhibitor, 5-aza2'-deoxycytidine, resulted in reexpression of CRBPI and CRBPIV gene expression in NPC cell lines. Both CRBPI and CRBPIV hypermethylations were also observed in 43/48 (87.8% and 26/48 (54.2% primary NPC tumors, respectively. Here, we reported for the first time that CRBPIV was transcriptionally inactivated by promoter hypermethylation in human cancer. Simultaneous methylation of CRBPI, CRBPIV, and RARβ2 was commonly found in NPC primary tumors. Our findings implied that epigenetic disruption of the CRBPs, CRBPI and CRBPIV, is important in NPC tumorigenesis and may contribute to the loss of retinoic acid responsiveness in cancer.

  3. Quantitation of the Noncovalent Cellular Retinol-Binding Protein, Type 1 Complex Through Native Mass Spectrometry

    Science.gov (United States)

    Li, Wenjing; Yu, Jianshi; Kane, Maureen A.

    2017-01-01

    Native mass spectrometry (MS) has become a valuable tool in probing noncovalent protein-ligand interactions in a sample-efficient way, yet the quantitative application potential of native MS has not been fully explored. Cellular retinol binding protein, type I (CrbpI) chaperones retinol and retinal in the cell, protecting them from nonspecific oxidation and delivering them to biosynthesis enzymes where the bound (holo-) and unbound (apo-) forms of CrbpI exert distinct biological functions. Using nanoelectrospray, we developed a native MS assay for probing apo- and holo-CrbpI abundance to facilitate exploring their biological functions in retinoid metabolism and signaling. The methods were developed on two platforms, an Orbitrap-based Thermo Exactive and a Q-IMS-TOF-based Waters Synapt G2S, where similar ion behaviors under optimized conditions were observed. Overall, our results suggested that within the working range ( 1-10 μM), gas-phase ions in the native state linearly correspond to solution concentration and relative ion intensities of the apo- and holo-protein ions can linearly respond to the solution ratios, suggesting native MS is a viable tool for relative quantitation in this system.

  4. Lecithin:retinol acyltransferase is critical for cellular uptake of vitamin A from serum retinol-binding protein.

    Science.gov (United States)

    Amengual, Jaume; Golczak, Marcin; Palczewski, Krzysztof; von Lintig, Johannes

    2012-07-13

    Vitamin A (all-trans-retinol) must be adequately distributed within the mammalian body to produce visual chromophore in the eyes and all-trans-retinoic acid in other tissues. Vitamin A is transported in the blood bound to retinol-binding protein (holo-RBP), and its target cells express an RBP receptor encoded by the Stra6 (stimulated by retinoic acid 6) gene. Here we show in mice that cellular uptake of vitamin A from holo-RBP depends on functional coupling of STRA6 with intracellular lecithin:retinol acyltransferase (LRAT). Thus, vitamin A uptake from recombinant holo-RBP exhibited by wild type mice was impaired in Lrat(-/-) mice. We further provide evidence that vitamin A uptake is regulated by all-trans-retinoic acid in non-ocular tissues of mice. When in excess, vitamin A was rapidly taken up and converted to its inert ester form in peripheral tissues, such as lung, whereas in vitamin A deficiency, ocular retinoid uptake was favored. Finally, we show that the drug fenretinide, used clinically to presumably lower blood RBP levels and thus decrease circulating retinol, targets the functional coupling of STRA6 and LRAT to increase cellular vitamin A uptake in peripheral tissues. These studies provide mechanistic insights into how vitamin A is distributed to peripheral tissues in a regulated manner and identify LRAT as a critical component of this process.

  5. Peroxidation stimulated by lipid hydroperoxides on bovine retinal pigment epithelium mitochondria: effect of cellular retinol-binding protein.

    Science.gov (United States)

    Terrasa, Ana M; Guajardo, Margarita H; Catalá, Angel

    2003-07-01

    This study analyzes the effect of cellular retinol-binding protein (CRBP), partially purified from retinal pigment epithelium (RPE) cytosol, on the non-enzymatic lipid peroxidation induced by fatty acid hydroperoxides of mitochondrial membranes isolated from bovine RPE. The effect of different amounts (50, 75 and 100 nmol) of linoleic acid hydroperoxide (LHP), arachidonic acid hydroperoxide (AHP) and docosahexaenoic acid hydroperoxide (DHP) on the lipid peroxidation of RPE mitochondria was studied; RPE mitochondria deprived of exogenously added hydroperoxide was utilized as control. The process was measured simultaneously by determining chemiluminescence as well as polyunsaturated fatty acid (PUFA) degradation of total lipids isolated from RPE mitochondria. The addition of hydroperoxides to RPE mitochondria produces a marked increase in light emission that was hydroperoxide concentration dependent. The highest value of activation was produced by LHP. The major difference in the fatty acid composition of total lipids isolated from native and peroxidized RPE mitochondria incubated with and without hydroperoxides was found in the docosahexaenoic acid content, this decreased 40.90+/-3.01% in the peroxidized group compared to native RPE mitochondria. The decrease was significantly high: 86.32+/-2.57% when the lipid peroxidation was stimulated by 100 nmol of LHP. Inhibition of lipid peroxidation (decrease of chemiluminescence) was observed with the addition of increasing amounts (100-600 microg) of CRBP to RPE mitochondria. The inhibitory effect reaches the highest values in the presence of LHP.

  6. 21 CFR 866.5765 - Retinol-binding protein immunological test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Retinol-binding protein immunological test system....5765 Retinol-binding protein immunological test system. (a) Identification. A retinol-binding protein... the retinol-binding protein that binds and transports vitamin A in serum and urine. Measurement...

  7. Photoperiodic regulation of cellular retinol binding protein, CRBP1 [corrected] and nestin in tanycytes of the third ventricle ependymal layer of the Siberian hamster.

    Science.gov (United States)

    Barrett, Perry; Ivanova, Elena; Graham, E Scott; Ross, Alexander W; Wilson, Dana; Plé, Helene; Mercer, Julian G; Ebling, Francis J; Schuhler, Sandrine; Dupré, Sandrine M; Loudon, Andrew; Morgan, Peter J

    2006-12-01

    Tanycytes in the ependymal layer of the third ventricle act both as a barrier and a communication gateway between the cerebrospinal fluid, brain and portal blood supply to the pituitary gland. However, the range, importance and mechanisms involved in the function of tanycytes remain to be explored. In this study, we have utilized a photoperiodic animal to examine the expression of three unrelated gene sequences in relation to photoperiod-induced changes in seasonal physiology and behaviour. We demonstrate that cellular retinol binding protein [corrected] (CRBP1), a retinoic acid transport protein, GPR50, an orphan G-protein-coupled receptor and nestin, an intermediate filament protein, are down-regulated in short-day photoperiods. The distribution of the three sequences is very similar, with expression located in cells with tanycyte morphology in the region of the ependymal layer where tanycytes are located. Furthermore, CRBP1 expression in the ependymal layer is shown to be independent of a circadian clock and altered testosterone levels associated with testicular regression in short photo-period. Pinealectomy of Siberian hamsters demonstrates CRBP1 expression is likely to be dependent on melatonin output from the pineal gland. This provides evidence that tanycytes are seasonally responsive cells and are likely to be an important part of the mechanism to facilitate seasonal physiology and behaviour in the Siberian hamster.

  8. Retinol-binding protein 4 and its membrane receptor STRA6 control adipogenesis by regulating cellular retinoid homeostasis and retinoic acid receptor α activity.

    Science.gov (United States)

    Muenzner, Matthias; Tuvia, Neta; Deutschmann, Claudia; Witte, Nicole; Tolkachov, Alexander; Valai, Atijeh; Henze, Andrea; Sander, Leif E; Raila, Jens; Schupp, Michael

    2013-10-01

    Retinoids are vitamin A (retinol) derivatives and complex regulators of adipogenesis by activating specific nuclear receptors, including the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Circulating retinol-binding protein 4 (RBP4) and its membrane receptor STRA6 coordinate cellular retinol uptake. It is unknown whether retinol levels and the activity of RAR and RXR in adipocyte precursors are linked via RBP4/STRA6. Here, we show that STRA6 is expressed in precursor cells and, dictated by the apo- and holo-RBP4 isoforms, mediates bidirectional retinol transport that controls RARα activity and subsequent adipocyte differentiation. Mobilization of retinoid stores in mice by inducing RBP4 secretion from the liver activated RARα signaling in the precursor cell containing the stromal-vascular fraction of adipose tissue. Retinol-loaded holo-RBP4 blocked adipocyte differentiation of cultured precursors by activating RARα. Remarkably, retinol-free apo-RBP4 triggered retinol efflux that reduced cellular retinoids, RARα activity, and target gene expression and enhanced adipogenesis synergistically with ectopic STRA6. Thus, STRA6 in adipocyte precursor cells links nuclear RARα activity to the circulating RBP4 isoforms, whose ratio in obese mice was shifted toward limiting the adipogenic potential of their precursors. This novel cross talk identifies a retinol-dependent metabolic function of RBP4 that may have important implications for the treatment of obesity.

  9. Plasma levels of osteocalcin and retinol binding protein-4 in patients with medullary thyroid carcinoma

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    Jabar Lotfi

    2014-04-01

    Conclusion: According to difference between plasma levels of osteocalcin and retinol binding protein-4 in patients suffered of medullary thyroid carcinoma comparison with normal subjects, it can be said that, probably medullary thyroid carcinoma has effect on bone and adipose tissue metabolism, so osteocalcin and retinol binding protein-4 hormones have potential to be used for confirmation of diagnosis or following treatment of medullary thyroid carcinoma.

  10. Massive bowel resection upregulates the intestinal mRNA expression levels of cellular retinol-binding protein II and apolipoprotein A-IV and alters the intestinal vitamin A status in rats.

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    Hebiguchi, Taku; Mezaki, Yoshihiro; Morii, Mayako; Watanabe, Ryo; Yoshikawa, Kiwamu; Miura, Mitsutaka; Imai, Katsuyuki; Senoo, Haruki; Yoshino, Hiroaki

    2015-03-01

    Short bowel (SB) syndrome causes the malabsorption of various nutrients. Among these, vitamin A is important for a number of physiological activities. Vitamin A is absorbed by epithelial cells of the small intestine and is discharged into the lymphatic vessels as a component of chylomicrons and is delivered to the liver. In the present study, we used a rat model of SB syndrome in order to assess its effects on the expression of genes associated with the absorption, transport and metabolism of vitamin A. In the rats with SB, the intestinal mRNA expression levels of cellular retinol-binding protein II (CRBP II, gene symbol Rbp2) and apolipoprotein A-IV (gene symbol Apoa4) were higher than those in the sham-operated rats, as shown by RT-qPCR. Immunohistochemical analysis revealed that absorptive epithelial cells stained positive for both CRBP II and lecithin retinol acyltransferase, which are both required for the effective esterification of vitamin A. In the rats with SB, the retinol content in the ileum and the retinyl ester content in the jejunum were lower than those in the sham-operated rats, as shown by quantitative analysis of retinol and retinyl esters by high performance liquid chromatography. These results suggest that the elevated mRNA expression levels of Rbp2 and Apoa4 in the rats with SB contribute to the effective esterification and transport of vitamin A.

  11. Effect of renal replacement therapy on retinol-binding protein 4 isoforms

    DEFF Research Database (Denmark)

    Frey, Simone K; Henze, Andrea; Nagl, Britta;

    2009-01-01

    Retinol-binding protein 4 (RBP4) levels are elevated in the serum of patients with kidney dysfunction. We recently showed that RBP4 isoforms including apo-RBP4 (RBP4 not bound to retinol) and RBP4 truncated at the C-terminus (RBP4-L, RBP4-LL) are increased in the serum of patients with kidney dis...

  12. Micro-ELISA for the quantitation of human urinary and serum retinol-binding protein

    DEFF Research Database (Denmark)

    Jensen, T; Deckert, M; Dawnay, A;

    1989-01-01

    ) and dilution of urine was linear. The within-assay coefficient of variation ranged from 1.2-3.1% and the day-to-day coefficient of variation from 9.2-10.5% depending on concentration. The correlation with urinary retinol-binding protein determined by radioimmunoassay was good (n = 90, r = 0.95). In vitro...

  13. Impaired retinal function and vitamin A availability in mice lacking retinol-binding protein.

    OpenAIRE

    Quadro, L; Blaner, W S; Salchow, D J; Vogel, S.; Piantedosi, R; Gouras, P; Freeman, S; Cosma, M P; Colantuoni, V; Gottesman, M E

    1999-01-01

    Retinol-binding protein (RBP) is the sole specific transport protein for retinol (vitamin A) in the circulation, and its single known function is to deliver retinol to tissues. Within tissues, retinol is activated to retinoic acid, which binds to nuclear receptors to regulate transcription of >300 diverse target genes. In the eye, retinol is also activated to 11-cis-retinal, the visual chromophore. We generated RBP knockout mice (RBP(-/-)) by gene targeting. These mice have several phenotypes...

  14. Retinol-Binding Protein 4 and Its Relation to Insulin Resistance in Obese Children before and after Weight Loss

    OpenAIRE

    Reinehr, Thomas; Stoffel-Wagner, Birgit; Roth, Christian L.

    2008-01-01

    Context: There are limited and controversial data concerning the relationships between retinol-binding protein 4 (RBP4), weight status, and insulin resistance in obese humans and especially in children.

  15. Recombinant fusion protein of albumin-retinol binding protein inactivates stellate cells

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    Choi, Soyoung; Park, Sangeun; Kim, Suhyun [Laboratory of Cellular Oncology, Korea University Graduate School of Medicine, Ansan, Gyeonggi do 425-707 (Korea, Republic of); Lim, Chaeseung [Department of Laboratory Medicine, Korea University Guro Hospital, Seoul 152-703 (Korea, Republic of); Kim, Jungho [Department of Life Science, Sogang University, Seoul 121-742 (Korea, Republic of); Cha, Dae Ryong [Department of Internal Medicine, Korea University Ansan Hospital, Ansan, Gyeonggi do 425-020 (Korea, Republic of); Oh, Junseo, E-mail: ohjs@korea.ac.kr [Laboratory of Cellular Oncology, Korea University Graduate School of Medicine, Ansan, Gyeonggi do 425-707 (Korea, Republic of)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer We designed novel recombinant albumin-RBP fusion proteins. Black-Right-Pointing-Pointer Expression of fusion proteins inactivates pancreatic stellate cells (PSCs). Black-Right-Pointing-Pointer Fusion proteins are successfully internalized into and inactivate PSCs. Black-Right-Pointing-Pointer RBP moiety mediates cell specific uptake of fusion protein. -- Abstract: Quiescent pancreatic- (PSCs) and hepatic- (HSCs) stellate cells store vitamin A (retinol) in lipid droplets via retinol binding protein (RBP) receptor and, when activated by profibrogenic stimuli, they transform into myofibroblast-like cells which play a key role in the fibrogenesis. Despite extensive investigations, there is, however, currently no appropriate therapy available for tissue fibrosis. We previously showed that the expression of albumin, composed of three homologous domains (I-III), inhibits stellate cell activation, which requires its high-affinity fatty acid-binding sites asymmetrically distributed in domain I and III. To attain stellate cell-specific uptake, albumin (domain I/III) was coupled to RBP; RBP-albumin{sup domain} {sup III} (R-III) and albumin{sup domain} {sup I}-RBP-albumin{sup III} (I-R-III). To assess the biological activity of fusion proteins, cultured PSCs were used. Like wild type albumin, expression of R-III or I-R-III in PSCs after passage 2 (activated PSCs) induced phenotypic reversal from activated to fat-storing cells. On the other hand, R-III and I-R-III, but not albumin, secreted from transfected 293 cells were successfully internalized into and inactivated PSCs. FPLC-purified R-III was found to be internalized into PSCs via caveolae-mediated endocytosis, and its efficient cellular uptake was also observed in HSCs and podocytes among several cell lines tested. Moreover, tissue distribution of intravenously injected R-III was closely similar to that of RBP. Therefore, our data suggest that albumin-RBP fusion protein comprises

  16. Retinol-binding protein, acute phase reactants and Helicobacter pylori infection in patients with gastric adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    Nicolas Tsavaris; Christos Koufos; Athanasios Archimandritis; Christos Kosmas; Petros Kopterides; Dimitrios Tsikalakis; Hlias Skopelitis; Fotini Sakelaridi; Nikitas Papadoniou; Michalis Tzivras; Vasilios Balatsos

    2005-01-01

    AIM: To determine the serum levels of c-reactive protein (CRP), transferrin (TRF), a2-macroglobulin (A2M),ceruloplasmin (CER), a1-acid glycoprotein (AAG), prealbumin (P-ALB) and retinol-binding protein (RBP) in gastric carcinoma patients and to explore their possible correlation with underlying Helicobacter pylori (H pylon)infection.METHODS: We measured the serum levels of CRP, TRF,A2M, CER, AAG, P-ALB, and RBP in 153 preoperative patients (93 males; mean age: 63.1±11.3 years) with non-cardia gastric adenocarcinoma and 19 healthy subjects.RESULTS: The levels of CRP, CER, RBP, andAAG in cancer patients were significantly higher than those in healthy controls (P<0.0001), while no difference was found regarding the TRF, P-ALB, and A2M levels. Cancer patients with H pylori infection had significantly lower RBP values compared to non-infected ones (P<0.0001)and also higher values of CRP and AAG (P = 0.09 and P = 0.08, respectively).CONCLUSION: High serum levels of CRP, CER and AAG in cancer patients do not seem to be related to H pylori infection. Retinol-binding protein seems to discriminate between infected and non-infected patients with gastric carcinoma. Further studies are needed to explore if it is directly involved in the pathogenesis of the disease or is merely an epiphenomenon.

  17. Evidence that kidney function but not type 2 diabetes determines retinol-binding protein 4 serum levels

    DEFF Research Database (Denmark)

    Henze, Andrea; Frey, Simone K; Raila, Jens

    2008-01-01

    It has been suggested that retinol-binding protein 4 (RBP4) links adiposity, insulin resistance, and type 2 diabetes. However, circulating RBP4 levels are also affected by kidney function. Therefore, the aim of this study was to test whether RBP4 serum levels are primarily associated with kidney...

  18. Cigarette smoking increases levels of retinol-binding protein-4 in healthy men with normal glucose tolerance

    Institute of Scientific and Technical Information of China (English)

    GAO Shan; WANG Yong-hui; LI Ming

    2012-01-01

    Background Smoking is related with insulin resistance and type 2 diabetes mellitus.Retinol-binding protein-4 is a new adipocytokine associated with insulin resistance.We investigated the serum levels of a series of adipocytokines including retinol-binding protein-4 in smokers and non-smokers to explore the possible roles of adipocytokines on smoking induced insulin resistance.Methods A total of 136 healthy male subjects (92 smokers and 44 non-smokers) with normal glucose tolerance were enrolled in the study.Adipocytokines including retinol-binding protein-4,visfatin,leptin,resistin,adiponectin were measured for the comparison between the two groups.Serum lipid profile,glucose,true insulin and proinsulin levels were measured as well in both groups.Food intake spectrum was also investigated.Results Both groups had similar profile of food consumption; visfatin,leptin,resistin and adiponectin,low-density lipoprotein cholesterol,high-density lipoprotein cholesterol,alanine aminotransferase,aspartate aminotransferase,as well as blood pressure and body mass index,were similar in both groups.Triglycerides,retinol-binding protein-4 and homeostatic model assessment index for insulin resistance were higher in smoker group ((2.58±2.53) vs.(1.60±0.94)mmol/L,(26.05±8.50) vs.(21.83±8.40) μg/ml,and 2.25±2.08 vs.1.58±1.15,respectively).Conclusion Smoking may have effect on insulin sensitivity,which is correlated with retinol-binding protein-4.

  19. HIV and schistosomiasis in rural Zimbabwe: the association of Retinol-binding protein with disease progression, inflammation and mortality

    OpenAIRE

    Sebastian Ranzi Kotzé; Rutendo Zinyama-Gutsire; Per Kallestrup; Christine Stabell Benn; Exnevia Gomo; Jan Gerstoft; Govert van Dam; Ole Hartvig Mortensen; Henrik Ullum; Christian Erikstrup

    2015-01-01

    Background: Vitamin A has widespread effects on immune function and is therefore interesting in HIV-infection. Retinol-binding protein (RBP or RBP4) is a negative acute-phase protein and a marker of vitamin A status. Our aim was to investigate the association of RBP with HIV progression, infection with schistosomiasis, inflammatory cytokines, and mortality. Methods: The study included 192 HIV-infected and 177 HIV-uninfected individuals from Mupfure in rural Zimbabwe. Of these, 208 were inf...

  20. The new platinum-based anticancer agent LA-12 induces retinol binding protein 4 in vivo

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    Bouchal Pavel

    2011-10-01

    Full Text Available Abstract Background The initial pharmacokinetic study of a new anticancer agent (OC-6-43-bis(acetato(1-adamantylamineamminedichloroplatinum (IV (LA-12 was complemented by proteomic screening of rat plasma. The objective of the study was to identify new LA-12 target proteins that serve as markers of LA-12 treatment, response and therapy monitoring. Methods Proteomic profiles were measured by surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF MS in 72 samples of rat plasma randomized according to LA-12 dose and time from administration. Correlation of 92 peak clusters with platinum concentration was evaluated using Spearman correlation analysis. Results We identified Retinol-binding protein 4 (RBP4 whose level correlated with LA-12 level in treated rats. Similar results were observed in randomly selected patients involved in Phase I clinical trials. Conclusions RBP4 induction is in agreement with known RBP4 regulation by amantadine and cisplatin. Since retinol metabolism is disrupted in many cancers and inversely associates with malignancy, these data identify a potential novel mechanism for the action of LA-12 and other similar anti-cancer drugs.

  1. Urinary retinol binding protein is a marker of the extent of interstitial kidney fibrosis.

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    Nicolas Pallet

    Full Text Available Currently, a non-invasive method to estimate the degree of interstitial fibrosis (IF in chronic kidney disease is not available in routine. The aim of our study was to evaluate the diagnostic performance of the measurement of urinary low molecular weight (LMW protein concentrations as a method to determine the extent of IF. The urines specimen from 162 consecutive patients who underwent renal biopsy were used in the analysis. Numerical quantification software based on the colorimetric analysis of fibrous areas was used to assess the percentage IF. Total proteinuria, albuminuria, and the urinary levels of retinol binding protein (RBP, alpha1-microglobulin (α1MG, beta 2-microglobulin (β2MG, transferrin, and IgG immunoglobulins were measured. There was a significant correlation between the degree of IF and the RBP/creatinine (creat ratio (R2: 0.11, p25% of the parenchyma was 95% when using a threshold of 20 mg/g creat. In conclusion, RBP appears to be a quantitative and non-invasive marker for the independent prediction of the extent of kidney IF. Because methods for the measurement of urinary RBP are available in most clinical chemistry departments, RBP measurement is appealing for implementation in the routine care of patients with chronic kidney disease.

  2. Retinol-Binding Protein 4 in Young Men With Low Versus Normal Birth Weight

    DEFF Research Database (Denmark)

    Ribel-Madsen, Rasmus; Brøns, Charlotte; Friedrichsen, Martin;

    2011-01-01

    Retinol-binding protein 4 (RBP4) is a plasma protein which is elevated in obesity and type 2 diabetes. We aimed to investigate whether RBP4 represents a mechanism underlying the associations between low birth weight (LBW), high-fat diet, and insulin resistance. Forty-six young, lean men with low (n......-ray absorptiometry scan, and plasma RBP4 by an enzyme-linked immunosorbent assay. RBP4 was not associated with birth weight, but with BMI (ß = 0.9 µg/ml (0.08; 1.8) (95% confidence interval), P = 0.03) and plasma levels of low-density lipoprotein cholesterol (ß = 5.3 µg/ml (1.9; 8.7), P = 0.03) and triglycerides (ß...... with peripheral glucose disposal rate or hepatic insulin resistance index. RBP4 levels were not influenced by overfeeding or related to peripheral and hepatic insulin resistance provoked by the dietary intervention. In conclusion, plasma RBP4 in young men associates with components of the metabolic syndrome...

  3. Retinol-binding protein-4 and hs-CRP levels in patients with migraine.

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    Tanik, Nermin; Celikbilek, Asuman; Metin, Aslı; Gocmen, Ayse Yesim; Inan, Levent Ertugrul

    2015-10-01

    Retinol-binding protein-4 (RBP4) and high-sensitivity C-reactive protein (hs-CRP) levels are associated with inflammation in patients with migraine. The release of proinflammatory cytokines during migraine results in recurrent sterile neurogenic inflammation. This study aimed to determine the correlation between RBP4 and hs-CRP levels, and migraine, which is considered an inflammatory disease. The study included 48 migraine patients and 40 age- and gender-matched controls. Migraine was diagnosed according to International Classification of Headache Disorders-II. The serum RBP4 level was measured using a commercial ELISA kit and hs-CRP was measured using an enzyme immunoassay test kit. The serum RBP4 level was significantly lower in the migraine patients than in the controls (P hs-CRP level was significantly higher in the migraine patients (P hs-CRP levels did not differ between the migraine patients with and without aura (P > 0.05). Migraine headache severity, frequency and duration were not correlated with serum RBP or hs-CRP levels (P > 0.05). The observed high hs-CRP level and low RBP4 level in migraine patients suggest that vitamin A might play a major role in the pathogenesis of migraine. It is known that inflammation is a key factor in many diseases. Additional research might result in a better understanding of the anti-inflammatory effects of vitamin A.

  4. The retinol esterifying enzyme LRAT supports cell signaling by retinol-binding protein and its receptor STRA6.

    Science.gov (United States)

    Marwarha, Gurdeep; Berry, Daniel C; Croniger, Colleen M; Noy, Noa

    2014-01-01

    Vitamin A, retinol, circulates in blood bound to retinol-binding protein (RBP). At some tissues, holo-RBP is recognized by a plasma membrane receptor termed STRA6, which serves a dual role: it mediates transport of retinol from RBP into cells, and it functions as a cytokine receptor that, on binding holo-RBP, activates JAK2/STAT5 signaling. As STAT target genes include SOCS3, an inhibitor of insulin receptor, holo-RBP suppresses insulin responses in STRA6-expressing cells. We have shown previously that the two functions of STRA6 are interdependent. These observations suggest factors that regulate STRA6-mediated retinol transport may also control STRA6-mediated cell signaling. One such factor is retinol metabolism, which enables cellular uptake of retinol by maintaining an inward-directed concentration gradient. We show here that lecithin:retinol acyl transferase (LRAT), which catalyzes esterification of retinol to its storage species retinyl esters, is necessary for activation of the STRA6/JAK2/STAT5 cascade by holo-RBP. In accordance, LRAT-null mice are protected from holo-RBP-induced suppression of insulin responses. Hence, STRA6 signaling, which requires STRA6-mediated retinol transport, is supported by LRAT-catalyzed retinol metabolism. The observations demonstrate that STRA6 regulates key cellular processes by coupling circulating holo-RBP levels and intracellular retinol metabolism to cell signaling.

  5. Expression of Serum Retinol Binding Protein and Transthyretin within Mouse Gastric Ghrelin Cells.

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    Angela K Walker

    Full Text Available Ghrelin is an orexigenic peptide hormone produced mainly by a distinct group of dispersed endocrine cells located within the gastric oxyntic mucosa. Besides secreted gene products derived from the preproghrelin gene, which include acyl-ghrelin, desacyl-ghrelin and obestatin, ghrelin cells also synthesize the secreted protein nesfatin-1. The main goal of the current study was to identify other proteins secreted from ghrelin cells. An initial gene chip screen using mRNAs derived from highly enriched pools of mouse gastric ghrelin cells demonstrated high levels of serum retinol-binding protein (RBP4 and transthyretin (TTR, both of which are known to circulate in the bloodstream bound to each other. This high expression was confirmed by quantitative RT-PCR using as template mRNA derived from the enriched gastric ghrelin cell pools and from two ghrelin-producing cell lines (SG-1 and PG-1. RBP4 protein also was shown to be secreted into the culture medium of ghrelin cell lines. Neither acute nor chronic caloric restriction had a significant effect on RBP4 mRNA levels within stomachs of C57BL/6J mice, although both manipulations significantly decreased stomach TTR mRNA levels. In vitro studies using PG-1 cells showed no effect on RBP4 release of octanoic acid, epinephrine or norepinephrine, all of which are known to act directly on ghrelin cells to stimulate ghrelin secretion. These data provide new insights into ghrelin cell physiology, and given the known functions of RBP4 and TTR, support an emerging role for the ghrelin cell in blood glucose handling and metabolism.

  6. Quantitative mass spectrometry evaluation of human retinol binding protein 4 and related variants.

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    Urban A Kiernan

    Full Text Available BACKGROUND: Retinol Binding Protein 4 (RBP4 is an exciting new biomarker for the determination of insulin resistance and type 2 diabetes. It is known that circulating RBP4 resides in multiple variants which may provide enhanced clinical utility, but conventional immunoassay methods are blind to such differences. A Mass Spectrometric immunoassay (MSIA technology that can quantitate total RBP4 as well as individual isoforms may provide an enhanced analysis for this biomarker. METHODS: RBP4 was isolated and detected from 0.5 uL of human plasma using MSIA technology, for the simultaneous quantification and differentiation of endogenous human RBP4 and its variants. RESULTS: The linear range of the assay was 7.81-500 ug/mL, and the limit of detection and limit of quantification were 3.36 ug/mL and 6.52 ug/mL, respectively. The intra-assay CVs were determined to be 5.1% and the inter-assay CVs were 9.6%. The percent recovery of the RBP4-MSIA ranged from 95 - 105%. Method comparison of the RBP4 MSIA vs the Immun Diagnostik ELISA yielded a Passing & Bablok fit of MSIA  = 1.05× ELISA - 3.09, while the Cusum linearity p-value was >0.1 and the mean bias determined by the Altman Bland test was 1.2%. CONCLUSION: The novel RBP4 MSIA provided a fast, accurate and precise quantitative protein measurement as compared to the standard commercially available ELISA. Moreover, this method also allowed for the detection of RBP4 variants that are present in each sample, which may in the future provide a new dimension in the clinical utility of this biomarker.

  7. Retinol binding protein 4 concentrations relate to enhanced atherosclerosis in obese patients with rheumatoid arthritis.

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    Patrick H Dessein

    Full Text Available BACKGROUND: Retinol binding protein 4 (RBP enhances metabolic risk and atherogenesis. Whether RBP4 contributes to cardiovascular risk in rheumatoid arthritis (RA is unknown. METHODS: We assessed RBP4 concentrations and those of endothelial activation molecules including E-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1 and monocyte chemoattractant protein-1 by ELISA, and the common carotid artery intima-media thickness (cIMT and carotid artery plaque by ultrasound in 217 (112 black and 105 white patients with RA. Relationships were identified in potential confounder and mediator adjusted mixed regression models. RESULTS: RBP4 concentrations were associated with systolic and mean blood pressure, and those of glucose and E-selectin (partial R = -0.207 (p = 0.003, -0.195 (p = 0.006, -0.155 (p = 0.03 and -0.191 (p = 0.007, respectively in all patients; these RBP4-cardiovascular risk relations were mostly reproduced in patients with but not without adverse traditional or non-traditional cardiovascular risk profiles. RBP4 concentrations were not associated with atherosclerosis in all patients, but related independently to cIMT (partial R = 0.297, p = 0.03 and plaque (OR (95%CI = 2.95 (1.31-6.68, p = 0.008 in those with generalized obesity, as well as with plaque in those with abdominal obesity (OR (95%CI  = 1.95 (1.12-3.42, p = 0.01. CONCLUSION: In the present study, RBP4 concentrations were inversely associated with metabolic risk and endothelial activation in RA. This requires further investigation. RBP4 concentrations were related to enhanced atherosclerosis in patients with generalized or/and abdominal obesity.

  8. Waist Circumference was Positively Correlated with Chemerin, Retinol-Binding Protein 4 and hsCRP

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    Lucia Herminawati

    2012-04-01

    Full Text Available BACKGROUND: Central obesity is associated with various chronic metabolic disorders characterized by abnormal cytokine production, increased acute phase reactants, and activation of inflammatory signaling pathways. This study was aimed to investigate the association of waist circumference, chemerin, and retinol binding protein (RBP-4 with inflammation in men with central obesity. METHODS: The research was conducted with a crosssectional design involving 68 centrally obese male subjects aged 30 to 60 years old, with waist circumference (WC >90 cm. All subjects fulfilled the inclusion and exclusion criteria. Anthropometric parameters, fasting glucose, creatinine, SGOT, SGPT, and hsCRP were measured. Serum concentrations of chemerin and RBP4 were measured by ELISA. RESULTS: The trend lines showed that chemerin, RBP4 and hsCRP increased with WC. Pearson correlation test showed a positively significant correlation between WC and hsCRP (r=0.242, p<0.05; and also between chemerin and hsCRP (r=0.244, p<0.05 and RBP4 (r=0.321, p<0.01. Subjects were stratified into four groups based on their chemerin and RBP4 levels (high chemerin/high RBP4, high chemerin/low RBP4, low chemerin/high RBP4, or low chemerin/low RBP4. Subjects who were in the high chemerin/low RBP4 group were more likely to have high level of inflammation (47.6%, but subjects with high chemerin/high RBP4 showed low level of inflammation (42.9% as compared with the other three groups. CONCLUSIONS: We concluded that increased WC was correlated with elevated levels of chemerin, RBP4 and hsCRP. High chemerin was correlated with increased level of RBP4 as well as with high level of inflammation. KEYWORDS: waist circumference, chemerin, RBP4, hsCRP, inflammation.

  9. The retinol esterifying enzyme LRAT supports cell signaling by retinol-binding protein and its receptor STRA6

    OpenAIRE

    Marwarha, Gurdeep; Berry, Daniel C.; Croniger, Colleen M.; Noy, Noa

    2014-01-01

    Vitamin A, retinol, circulates in blood bound to retinol-binding protein (RBP). At some tissues, holo-RBP is recognized by a plasma membrane receptor termed STRA6, which serves a dual role: it mediates transport of retinol from RBP into cells, and it functions as a cytokine receptor that, on binding holo-RBP, activates JAK2/STAT5 signaling. As STAT target genes include SOCS3, an inhibitor of insulin receptor, holo-RBP suppresses insulin responses in STRA6-expressing cells. We have shown previ...

  10. Saturation of retinol-binding protein correlates closely to the severity of alcohol-induced liver disease

    DEFF Research Database (Denmark)

    Wagnerberger, S.; Schäfer, C.; Bode, C.;

    2006-01-01

    Impaired metabolism of retinol has been shown to occur in alcohol-induced liver disease (ALD). The purpose of the present study was to investigate the saturation of retinol-binding protein (RBP) in 6 patients with different stages of ALD. Hospitalized alcohol consumers (n=118) with different stages......: 43.5+/-6.2%; ALD3: 29.0+/-5.1%). The present study indicates that plasma concentrations of retinol and RBP per se do not correlate to severity of ALD, but rather that the retinol/RBP ratio links to the severity of alcohol-induced liver damage. From these results, a reduced availability of retinol...

  11. Reproducibility of Retinol Binding Protein 4 and Omentin-1 Measurements over a Four Months Period: A Reliability Study in a Cohort of 207 Apparently Healthy Participants.

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    Clemens Wittenbecher

    Full Text Available The reliability of single time point measurements of the novel adipokines retinol-binding protein 4 and omentin-1 in the blood has not been evaluated in large samples yet. The present study aimed to assess the amount of biological variation of these two adipokines within individuals. The study sample comprised 207 participants (124 women and 83 men from Potsdam (Germany and surrounding areas, with an average age of 56.5 years (SD 4.2. Blood samples were collected from each participant twice, approximately four months apart. Using enzyme linked immunosorbent assays, the concentrations of retinol-binding protein 4 and omentin-1 were determined in EDTA plasma. As indicators of reliability, intraclass correlation coefficients (ICCs were calculated from the repeated biomarker measurements. The ICCs for repeated retinol-binding protein 4 and omentin-1 measurements were 0.77 (95% CI 0.71, 0.82 and 0.83 (95% CI 0.78, 0.87, respectively, indicating for both adipokines excellent reliability. ICCs were stable across strata according to sex, age, BMI, and blood pressure. Thus, for epidemiological studies it seems reasonable to rely on concentrations of retinol-binding protein 4 and omentin-1 in samples from a single time point if repeated measurements are not available.

  12. Pioglitazone Lowers Serum Retinol Binding Protein 4 by Suppressing its Expression in Adipose Tissue of Obese Rats

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    Chaoyu Zhu

    2015-01-01

    Full Text Available Background/Aims: Pioglitazone, a peroxisome proliferator-activated receptor γ activator, is clinically used to treat insulin resistance. However, the underlying mechanism of pioglitazone's action remains unclear. We investigated whether, and how, pioglitazone modulates serum level of retinol binding protein 4 (RBP4, an adipocytokine associated with obesity and insulin resistance. Methods: Insulin sensitivity was determined by oral glucose tolerance test, and RBP4 expression was detected by RT-PCR and Western blotting. Results: Pioglitazone treatment significantly decreased serum RBP4 levels in obese rats, which was correlated with reduced body weight and increased insulin sensitivity. Moreover, pioglitazone greatly decreased RBP4 mRNA and protein levels in adipose tissue but not in the liver. Consistently, pioglitazone treatment significantly reduced RBP4 protein expression in 3T3-L1 adipocytes but not in HepG2 cells. Conclusion: These results demonstrate that pioglitazone inhibits the level of serum RPB4 by suppressing RBP4 expression in adipose tissue of obese rats, suggesting that inhibiting RBP4 expression in adipocytes may provide a mechanism by which pioglitazone improves insulin sensitivity in insulin-resistant subjects.

  13. Signaling by vitamin A and retinol-binding protein in regulation of insulin responses and lipid homeostasis.

    Science.gov (United States)

    Berry, Daniel C; Noy, Noa

    2012-01-01

    Vitamin A, retinol, circulates in blood bound to serum retinol binding protein (RBP) and is transported into cells by a membrane protein termed stimulated by retinoic acid 6 (STRA6). It was reported that serum levels of RBP are elevated in obese rodents and humans, and that increased level of RBP in blood causes insulin resistance. A molecular mechanism by which RBP can exert such an effect is suggested by the recent discovery that STRA6 is not only a vitamin A transporter but also functions as a surface signaling receptor. Binding of RBP-ROH to STRA6 induces the phosphorylation of a tyrosine residue in the receptor C-terminus, thereby activating a JAK/STAT signaling cascade. Consequently, in STRA6-expressing cells such as adipocytes, RBP-ROH induces the expression of STAT target genes, including SOCS3, which suppresses insulin signaling, and PPARγ, which enhances lipid accumulation. RBP-retinol thus joins the myriad of cytokines, growth factors and hormones which regulate gene transcription by activating cell surface receptors that signal through activation of Janus kinases and their associated transcription factors STATs. This article is part of a Special Issue entitled Retinoid and Lipid Metabolism.

  14. Research Progress in Function of Retinol Binding Protein4 on Insulin Resistance Formation and Effects of Exercise on Retinol Binding Protein4%视黄醇结合蛋白4在胰岛素抵抗形成中的作用及其与运动关系的研究进展

    Institute of Scientific and Technical Information of China (English)

    张明军

    2012-01-01

    This paper summarizes the function of retinol binding protein 4 on insulin resistance formation and effects of exercise on retinol binding protein 4. RBP4 is an adipocyte - derived ' signal' that may contribute to the relationship between insulin resistance and obesity,type 2 diabetes. Retinol binding protein4 genetic polymorphism is relevant to insulin resistance formation too. Retinol binding protein4 could induce insulin resistance by suppression insulin signal protein. Exercise decreases retinol binding protein 4 level of normal subjects, obesity, and type 2 diabetes to improve insulin resistance.%对视黄醇结合蛋白4在胰岛素抵抗形成中的作用及其与运动关系的研究进展进行了综述研究。视黄醇结合蛋白4是将肥胖、2型糖尿病胰岛素抵抗联系起来的脂肪因子,视黄醇结合蛋白4遗传多态性亦与胰岛素抵抗的发生关系密切。视黄醇结合蛋白4能够通过抑制胰岛素信号蛋白诱导胰岛素抵抗。运动能够降低正常体重、肥胖、2型糖尿病对象的视黄醇结合蛋白4,改善胰岛素抵抗。

  15. Elevated serum triglyceride and retinol-binding protein 4 levels associated with fructose-sweetened beverages in adolescents.

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    Te-Fu Chan

    Full Text Available BACKGROUND: The metabolic effect of fructose in sugar-sweetened beverages (SSB has been linked to de novo lipogenesis and uric acid (UA production. OBJECTIVES: This study investigated the biological effects of SSB consumption on serum lipid profiles and retinol-binding protein 4 (RBP4 among Taiwanese adolescents. METHODS: We evaluated the anthropometric parameters and biochemical outcomes of 200 representative adolescents (98 boys and 102 girls who were randomly selected from a large-scale cross-sectional study. Data were analyzed using multiple regression models adjusted for covariates. RESULTS: Increased SSB consumption was associated with increased waist and hip circumferences, body mass index (BMI values and serum UA, triglyceride (TG and RBP4 levels. Adolescents who consumed >500 ml/day of beverages half-to-heavily sweetened with high-fructose corn syrup (HFCS exhibited TG and RBP4 levels 22.7 mg/dl and 13.92 ng/ml higher than non-drinkers, respectively. HFCS drinkers with hyperuricemia had higher TG levels than HFCS drinkers with normal UA levels (98.6 vs. 81.6 mg/dl. The intake of HFCS-rich SSBs and high value of BMI (≥24 interactively reinforced RBP4 levels among overweight/obese adolescents. Circulating RBP4 levels were significantly correlated with weight-related outcomes and TG and UA concentration among HFCS drinkers (r = 0.253 to 0.404, but not among non-drinkers. CONCLUSIONS: High-quantity HFCS-rich beverage consumption is associated with higher TG and RBP4 levels. Hyperuricemia is likely to intensify the influence of HFCS-rich SSB intake on elevated TG levels, and in overweight and obese adolescents, high BMI may modify the action of fructose on higher circulating levels of RBP4.

  16. Relation of Absolute or Relative Adiposity to Insulin Resistance, Retinol Binding Protein-4, Leptin, and Adiponectin in Type 2 Diabetes

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    You Lim Kim

    2012-12-01

    Full Text Available BackgroundCentral fat mass (CFM correlates with insulin resistance and increases the risk of type 2 diabetes and cardiovascular complications; however, peripheral fat mass (PFM is associated with insulin sensitivity. The aim of this study was to investigate the relation of absolute and relative regional adiposity to insulin resistance index and adipokines in type 2 diabetes.MethodsTotal of 83 overweighted-Korean women with type 2 diabetes were enrolled, and rate constants for plasma glucose disappearance (KITT and serum adipokines, such as retinol binding protein-4 (RBP4, leptin, and adiponectin, were measured. Using dual X-ray absorptiometry, trunk fat mass (in kilograms was defined as CFM, sum of fat mass on the lower extremities (in kilograms as PFM, and sum of CFM and PFM as total fat mass (TFM. PFM/TFM ratio, CFM/TFM ratio, and PFM/CFM ratio were defined as relative adiposity.ResultsMedian age was 55.9 years, mean body mass index 27.2 kg/m2, and mean HbA1c level 7.12±0.84%. KITT was positively associated with PMF/TFM ratio, PMF/CFM ratio, and negatively with CFM/TFM ratio, but was not associated with TFM, PFM, or CFM. RBP4 levels also had a significant relationship with PMF/TFM ratio and PMF/CFM ratio. Adiponectin, leptin, and apolipoprotein A levels were related to absolute adiposity, while only adiponectin to relative adiposity. In correlation analysis, KITT in type 2 diabetes was positively related with HbA1c, fasting glucose, RBP4, and free fatty acid.ConclusionThese results suggest that increased relative amount of peripheral fat mass may aggravate insulin resistance in type 2 diabetes.

  17. Effect of rosiglitazone on visfatin and retinol-binding protein-4 plasma concentrations in HIV-positive patients.

    Science.gov (United States)

    Haider, D G; Schindler, K; Mittermayer, F; Müller, M; Nowotny, P; Rieger, A; Luger, A; Ludvik, B; Wolzt, M

    2007-04-01

    Thiazolidinediones (TZD) may improve insulin resistance in patients with diabetes and HIV. The novel adipocytokines visfatin and retinol-binding protein-4 (RBP-4) have been proposed to influence the development of impaired glucose tolerance. The impact of TZD on these cytokines is yet unknown. In this randomized, double-blind, placebo-controlled parallel group study, 37 lean HIV-positive subjects aged 19-50 years were treated with 8 mg/day rosiglitazone (n=20) or placebo (n=17) for 6 months. Insulin sensitivity was estimated from the homeostasis model assessment (HOMA) index. Fasting visfatin, RBP-4, leptin, and adiponectin plasma concentrations were analyzed by immunoassays. Rosiglitazone had no effect on impaired insulin sensitivity, but increased median plasma visfatin from 6.2 ng/ml (95% CI: 5.9; 6.5) to 13.7 ng/ml (12.6; 19.1) (P<0.001) and adiponectin from 3.2 ng/ml (2.2; 4.0) to 4.0 ng/ml (3.3; 8.5; P<0.001). RBP-4 was lowered from 21.0 ng/ml (19.6; 23.1) to 16.3 ng/ml (15.2; 17.0; P<0.001), and leptin concentrations were unchanged. Adipocytokine concentrations were stable in subjects receiving placebo, where a deterioration in insulin sensitivity was detectable (P<0.05). Changes in visfatin and RBP-4 were correlated in subjects receiving rosiglitazone (r=-0.64, P<0.01) but not placebo (r=0.12, P=0.15). TZD treatment affects circulating adipocytokine concentrations in subjects with HIV. Reductions in RBP-4 and increases in visfatin may contribute to the pharmacodynamic action of TZD on glucose homeostasis. Quantification of adipocytokines might be useful to assess TZD treatment effectiveness in insulin-resistant subjects with HIV.

  18. Lower fetuin-A, retinol binding protein 4 and several metabolites after gastric bypass compared to sleeve gastrectomy in patients with type 2 diabetes.

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    Mia Jüllig

    Full Text Available BACKGROUND: Bypass of foregut secreted factors promoting insulin resistance is hypothesized to be one of the mechanisms by which resolution of type 2 diabetes (T2D follows roux-en-y gastric bypass (GBP surgery. AIM: To identify insulin resistance-associated proteins and metabolites which decrease more after GBP than after sleeve gastrectomy (SG prior to diabetes remission. METHODS: Fasting plasma from 15 subjects with T2D undergoing GBP or SG was analyzed by proteomic and metabolomic methods 3 days before and 3 days after surgery. Subjects were matched for age, BMI, metformin therapy and glycemic control. Insulin resistance was calculated using homeostasis model assessment (HOMA-IR. For proteomics, samples were depleted of abundant plasma proteins, digested with trypsin and labeled with iTRAQ isobaric tags prior to liquid chromatography-tandem mass spectrometry analysis. Metabolomic analysis was performed using gas chromatography-mass spectrometry. The effect of the respective bariatric surgery on identified proteins and metabolites was evaluated using two-way analysis of variance and appropriate post-hoc tests. RESULTS: HOMA-IR improved, albeit not significantly, in both groups after surgery. Proteomic analysis yielded seven proteins which decreased significantly after GBP only, including Fetuin-A and Retinol binding protein 4, both previously linked to insulin resistance. Significant decrease in Fetuin-A and Retinol binding protein 4 after GBP was confirmed using ELISA and immunoassay. Metabolomic analysis identified significant decrease of citrate, proline, histidine and decanoic acid specifically after GBP. CONCLUSION: Greater early decrease was seen for Fetuin-A, Retinol binding protein 4, and several metabolites after GBP compared to SG, preceding significant weight loss. This may contribute to enhanced T2D remission observed following foregut bypass procedures.

  19. Rescue of retinal morphology and function in a humanized mouse at the mouse retinol-binding protein locus.

    Science.gov (United States)

    Liu, Li; Suzuki, Tomohiro; Shen, Jingling; Wakana, Shigeharu; Araki, Kimi; Yamamura, Ken-Ichi; Lei, Lei; Li, Zhenghua

    2017-01-30

    Retinol-binding protein RBP4 is the specific carrier for retinol in the blood. We previously produced a Rbp4-deficient (Rbp4(-/-)) mouse that showed electroretinogram (ERG) abnormalities, accompanied by histological and electron-microscopic changes such as fewer synapses in the inner plexiform layer in the central retina. To address whether human RBP4 gene expression can rescue the phenotypes observed in Rbp4(-/-) mice, we produced a humanized (Rbp4(hRBP4orf/ hRBP4orf)) mouse with a human RBP4 open reading frame in the mouse Rbp4 locus using a Cre-mutant lox recombination system. In Rbp4(hRBP4orf/hRBP4orf) mice, the tissue-specific expression pattern of hRBP4orf was roughly the same as that of mouse Rbp4. ERG and morphological abnormalities observed in Rbp4(-/-) mice were rescued in Rbp4(hRBP4orf/hRBP4orf) mice as early as 7 weeks of age. The temporal expression pattern of hRBP4orf in the liver of Rbp4(hRBP4orf/hRBP4orf) mice was similar to that of mouse Rbp4 in Rbp4(+/+)mice. In contrast, hRBP4orf expression levels in eyes were significantly lower at 6 and 12 weeks of age compared with mouse Rbp4 but were restored to the control levels at 24 weeks. The serum hRBP4 levels in Rbp4(hRBP4orf/hRBP4orf) mice were approximately 30% of those in Rbp4(+/+) at all ages examined. In accordance with this finding, the plasma retinol levels remained low in Rbp4(hRBP4orf/hRBP4orf) mice. Retinol accumulation in the liver occurred in control and Rbp4(hRBP4orf/hRBP4orf) mice but was higher in Rbp4(hRBP4orf/hRBP4orf) mice at 30 weeks of age. Mouse transthyretin expression was not altered in Rbp4(-/-) or Rbp4(hRBP4orf/hRBP4orf) mice. Taken together, 30% of the serum RBP4 level was sufficient to correct the abnormal phenotypes observed in Rbp4(-/-) mice.Laboratory Investigation advance online publication, 30 January 2017; doi:10.1038/labinvest.2016.156.

  20. Alterations of retinol-binding protein 4 species in patients with different stages of chronic kidney disease and their relation to lipid parameters

    DEFF Research Database (Denmark)

    Henze, Andrea; Frey, Simone K; Raila, Jens;

    2010-01-01

    Retinol-binding protein 4 (RBP4) is elevated in patients with chronic kidney disease (CKD) and has been discussed as marker of kidney function. In addition to an elevated concentration, the existence of truncated RBP4 species, RBP4-L (truncated at last C-terminal leucine) and RBP4-LL (truncated......) was assessed in serum of 45 healthy controls and 52 patients with stage 2-5 of CKD using ELISA and RBP4 immunoprecipitation with subsequent MALDI-TOF-MS analysis. A reduction of glomerular filtration rate was accompanied by a gradual elevation of RBP4 serum levels and relative amounts of RBP4-LL. Correlation...

  1. Isoforms of retinol binding protein 4 (RBP4) are increased in chronic diseases of the kidney but not of the liver

    DEFF Research Database (Denmark)

    Frey, Simone K; Nagl, Britta; Henze, Andrea

    2008-01-01

    The levels of retinol-binding protein 4 (RBP4) - the carrier protein for Vitamin A in plasma - are tightly regulated under healthy circumstances. The kidney, the main site of RBP4 catabolism, contributes to an elevation of RBP4 levels during chronic kidney disease (CKD) whereas during chronic liver...... disease (CLD) RBP4 levels decrease. Little is known about RBP4 isoforms including apo-RBP4, holo-RBP4 as well as RBP4 truncated at the C-terminus (RBP4-L and RBP4-LL) except that RBP4 isoforms have been reported to be increased in hemodialysis patients. Since it is not known whether CLD influence RBP4...

  2. Retinol-binding protein 4 in twins: regulatory mechanisms and impact of circulating and tissue expression levels on insulin secretion and action

    DEFF Research Database (Denmark)

    Ribel-Madsen, Rasmus; Friedrichsen, Martin; Vaag, Allan

    2009-01-01

    OBJECTIVE: Retinol-binding protein (RBP) 4 is an adipokine of which plasma levels are elevated in obesity and type 2 diabetes. The aims of the study were to identify determinants of plasma RBP4 and RBP4 mRNA expression in subcutaneous adipose tissue (SAT) and skeletal muscle and to investigate...... expression was not associated with circulatory RBP4. CONCLUSIONS: In conclusion, our data indicate that RBP4 levels in plasma, skeletal muscle, and fat may be linked to insulin resistance and type 2 diabetes in a secondary and noncausal manner....... the association between RBP4 and in vivo measures of glucose metabolism. RESEARCH DESIGN AND METHODS: The study population included 298 elderly twins (aged 62-83 years), with glucose tolerance ranging from normal to overt type 2 diabetes, and 178 young (aged 25-32 years) and elderly (aged 58-66 years) nondiabetic...

  3. The STRA6 receptor is essential for retinol-binding protein-induced insulin resistance but not for maintaining vitamin A homeostasis in tissues other than the eye.

    Science.gov (United States)

    Berry, Daniel C; Jacobs, Hugues; Marwarha, Gurdeep; Gely-Pernot, Aurore; O'Byrne, Sheila M; DeSantis, David; Klopfenstein, Muriel; Feret, Betty; Dennefeld, Christine; Blaner, William S; Croniger, Colleen M; Mark, Manuel; Noy, Noa; Ghyselinck, Norbert B

    2013-08-23

    The plasma membrane protein STRA6 is thought to mediate uptake of retinol from its blood carrier retinol-binding protein (RBP) into cells and to function as a surface receptor that, upon binding of holo-RBP, activates a JAK/STAT cascade. It was suggested that STRA6 signaling underlies insulin resistance induced by elevated serum levels of RBP in obese animals. To investigate these activities in vivo, we generated and analyzed Stra6-null mice. We show that the contribution of STRA6 to retinol uptake by tissues in vivo is small and that, with the exception of the eye, ablation of Stra6 has only a modest effect on retinoid homeostasis and does not impair physiological functions that critically depend on retinoic acid in the embryo or in the adult. However, ablation of Stra6 effectively protects mice from RBP-induced suppression of insulin signaling. Thus one biological function of STRA6 in tissues other than the eye appears to be the coupling of circulating holo-RBP levels to cell signaling, in turn regulating key processes such as insulin response.

  4. Design, synthesis, and evaluation of nonretinoid retinol binding protein 4 antagonists for the potential treatment of atrophic age-related macular degeneration and Stargardt disease.

    Science.gov (United States)

    Cioffi, Christopher L; Dobri, Nicoleta; Freeman, Emily E; Conlon, Michael P; Chen, Ping; Stafford, Douglas G; Schwarz, Daniel M C; Golden, Kathy C; Zhu, Lei; Kitchen, Douglas B; Barnes, Keith D; Racz, Boglarka; Qin, Qiong; Michelotti, Enrique; Cywin, Charles L; Martin, William H; Pearson, Paul G; Johnson, Graham; Petrukhin, Konstantin

    2014-09-25

    Accumulation of lipofuscin in the retina is associated with pathogenesis of atrophic age-related macular degeneration and Stargardt disease. Lipofuscin bisretinoids (exemplified by N-retinylidene-N-retinylethanolamine) seem to mediate lipofuscin toxicity. Synthesis of lipofuscin bisretinoids depends on the influx of retinol from serum to the retina. Compounds antagonizing the retinol-dependent interaction of retinol-binding protein 4 (RBP4) with transthyretin in the serum would reduce serum RBP4 and retinol and inhibit bisretinoid formation. We recently showed that A1120 (3), a potent carboxylic acid based RBP4 antagonist, can significantly reduce lipofuscin bisretinoid formation in the retinas of Abca4(-/-) mice. As part of the NIH Blueprint Neurotherapeutics Network project we undertook the in vitro exploration to identify novel conformationally flexible and constrained RBP4 antagonists with improved potency and metabolic stability. We also demonstrate that upon acute and chronic dosing in rats, 43, a potent cyclopentyl fused pyrrolidine antagonist, reduced circulating plasma RBP4 protein levels by approximately 60%.

  5. Structure and cell-specific expression of a cloned human retinol binding protein gene: the 5'-flanking region contains hepatoma specific transcriptional signals.

    Science.gov (United States)

    D'Onofrio, C; Colantuoni, V; Cortese, R

    1985-08-01

    Human plasma retinol binding protein (RBP) is coded by a single gene and is specifically synthesized in the liver. We have characterized a lambda clone, from a human DNA library, carrying the gene coding for plasma RBP. Southern blot analysis and DNA sequencing show that the gene is composed of six exons and five introns. Primer elongation and S1 mapping experiments allowed the definition of the initiation of transcription and the identification of the putative promoter. The 5'-flanking region of the RBP gene was fused upstream to the coding sequence of the bacterial enzyme chloramphenicol acetyl transferase (CAT): the chimeric gene was introduced, by calcium phosphate precipitation, into the human hepatoma cell line Hep G2 and into HeLa cells. Efficient expression of CAT was obtained only in Hep G2. Primer elongation analysis of the RNA extracted from transfected Hep G2 showed that initiation of transcription of the transfected chimeric gene occurs at a position identical to that of the natural gene. Transcriptional analysis of Bal31 deletions from the 3' end of the RBP 5'-flanking DNA allowed the identification of the RBP gene promoter.

  6. The association of carotid intima media thickness with retinol binding protein-4 and total and high molecular weight adiponectin in type 2 diabetic patients

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    Mansouri Masoumeh

    2012-08-01

    Full Text Available Abstract Background The aim of this study was to investigate whether carotid intima media thickness (CIMT is associated with serum level of retinol- binding protein-4 (RBP4 and total and high molecular weight (HMW adiponectin in type 2 diabetes (T2DM without clinical symptom of atherosclerotic disease. Method 101 type 2 diabetic patients (mean age, 53.63 ± 8.42 years and 42 body mass index (BMI matched control (mean age 50.1 ± 8.4 were recruited. The CIMT was assessed by using B-mode ultrasonography, while serum levels of RBP4 and total and HMW adiponectin were measured by using enzyme linked immunosorbant assay (ELISA. Linear regression analysis was performed with CIMT as dependent variable and adipokines and cardio metabolic risk factors as independent variables. Result The CIMT was higher in diabetic group compared to control group (p Age (B = 0.44 P Conclusion In conclusion, the present study showed that serum levels of RBP4 or total and HMW adiponectin were not potential predictors of CIMT in type 2 diabetic patients who exposed to this risk factor at least for nine years.

  7. Impact of Serum Retinol-Binding Protein 4 Levels on Regulation of Remnant-Like Particles Triglyceride in Type 2 Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Naoto Yamaaki

    2013-01-01

    Full Text Available Background. Although retinol-binding protein 4 (RBP4 associates with insulin resistance and remnant-like particles triglyceride (RLP-TG elevated in the insulin resistant state, few data exist regarding the relationship between RBP4 and RLP-TG. Subjects and Methods. The study included 92 Japanese type 2 diabetic mellitus (T2DM male patients (age years, body mass index (BMI  kg/m2, waist circumference (WC  cm, and HbA1c (NGSP %. Patients on medications affecting insulin sensitivity, including fibrates, biguanides, and thiazolidinedione, were excluded. Visceral fat area (VFA and subcutaneous fat area (SFA were measured by computed tomography. Results. RBP4 levels showed a significant positive correlation with RLP-TG ( and , TG ( and , RLP-TG/TG ( and , and age ( and , although there was no significant correlation with VFA, SFA, adiponectin levels, or homeostasis model of assessment insulin resistance (HOMA-R. Multiple regression analysis revealed that RBP4 was an independent determinant of RLP-TG ( but was not a determinant of TG. Conclusions. RBP4 correlates positively with serum RLP-TG independent of fat accumulation in T2DM. RBP4 may regulate remnant metabolism independent of glycemic control in T2DM.

  8. High fat diet induced insulin resistance and elevated retinol binding protein 4 in female rats; treatment and protection with Berberis vulgaris extract and vitamin A.

    Science.gov (United States)

    El-Sayed, Mohamed Mohammed; Ghareeb, Doaa Ahmad; Talat, Heba Allah; Sarhan, Eman Mohammed

    2013-11-01

    This research was conducted to investigate two main aims; the first aim was to find if there is a relationship between insulin resistance (IR) and retinol binding protein 4 (RBP4). The second aim was to use berberis vulgaris extract and vitamin A as protective and/or curative agents against insulin resistance. IR was developed by feeding the female rats a high fat diet (HFD) for six weeks then treating or protecting them with b. vulgaris extract (0.2 g/Kg body weight) or vitamin A (12.8μg/Kg/day) for two weeks. HFD intake elevated insulin level and RBP4 expression that associated with hyperglycemia and hyperlipidemia. Co-administration of vitamin A and B. vulgaris extracts reduced blood glucose level, insulin, body weight and RBP4 expression before, during and after HFD. Furthermore, vitamin A reduced the blood glucose, triglycerides (TG) and cholesterol levels. IR syndrome associated with the RBP 4 alteration that gives high indication about the role of RBP4 expression in the IR progression and development. Furthermore, the treatment with vitamin A and/or b. vulgaris alleviated the IR syndrome through the action on RBP4 and Insulin secretion. On the other hand, vitamin A must be avoided for the predisposed IR and prediabetic patients.

  9. Evaluation of serum retinol-binding protein on the early diagnosis of renal injury%血清视黄醇结合蛋白对评价早期肾损伤的诊断价值

    Institute of Scientific and Technical Information of China (English)

    汪明东; 孙立山; 郑慧雅; 陆柳; 范列英

    2011-01-01

    目的 探讨血清视黄醇结合蛋白(RBP)对早期肾损伤的诊断价值.方法 采用免疫比浊法检测343例肾病患者及200例健康人血清RBP的变化.用酶法检测其血清肌酐(Cr) 的变化,并由简化MDRD公式计算出估计的肾小球滤过率(GFR).结果 肾功正常组RBP的结果与对照组比较,差异有统计学意义(P0.05).结论 RBP可作为诊断肾病早期损害的敏感性指标,同时检测血清Cr有助于提高其阳性率,但血RBP的敏感性优于血清Cr.%Objective To explore the evaluation of retinol-binding protein(RBP) on the early diagnosis of renal injury. Methods The changes of serum RBP were determined in 200 healthy subjects and 343 patients with nephropathy by immune transmission nephelometry. And the changes of serum creatinine (Cr) by enzyme,Kstimate GFR (eGFR) was estimated with Modification of Diet in Renal Disease (MDRD) equations. Results The levels of serum retinol-binding protein in the normal renal function group were higher than those in the control group(P0. 05). Conclusion The serum retinol-binding protein can be used as a sensitive indicator for the diagnosis of early renal damage in nephropathy. It contributes to improving the positive rate to measure serum creatinine at the same time,and the sensitiveness of serum retinol-binding protein is superior to serum creatinine.

  10. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus.

    Science.gov (United States)

    Rey-Burusco, M Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R; Roe, Andrew J; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W; Córsico, Betina; Smith, Brian O

    2015-11-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein-ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male.

  11. Anti-diabetic effects of cinnamaldehyde and berberine and their impacts on retinol-binding protein 4 expression in rats with type 2 diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; XU Ya-cheng; GUO Fang-jian; MENG Ye; LI Ming-li

    2008-01-01

    Background Retinol binding protein 4 (RBP4),as an adipocyte secreted cytokine,was recently found to be inversely correlated with expression of glucose transporter 4 (GLUT4) in insulin resistance (IR) state and to have an intimate relationship with IR and type 2 diabetes mellitus (T2DM).The present study aimed to evaluate the anti-diabetic efficacy of cinnamaldehyde (tin),berberine (Bet),and metformin (Met) as well as their impacts on the RBP4-GLUT4 system.Methods Rat models of T2DM were established by combination of intraperitoneal injection of low-dose streptozotocin and high fat diet induction.Rats were divided into five groups:the control group,the diabetes group,the diabetes+Ber group,the diabetes+Cin group,and the diabetes+Met group.Western blotting was used to detect the serum or tissue RBP4 and GLUT4 protein levels.Results After treatment for four weeks,both Cin and Ber displayed significant hypolipidemic,hypoglycemic,and insulin sensitizing functions (P<0.01) compared with the control group.Their effects on lowering fasting plasma glucose (FPG),low density lipoprotein-cholesterol (LDL-C) and homeostasis model assessment of insulin resistance (HOMA-IR) seem even better than that of Met.Cin and Bet markedly lowered serum RBP4 levels and up-regulated the expression of tissue GLUT4 protein,and Cin seemed more notable in affecting these two proteins.Conclusions Both Cin and Ber display an exciting anti-diabetic efficacy in this study and may be of great value for the treatment of type 2 diabetes.Their mechanisms involve the RBP4-GLUT4 system,during which the serum RBP4 levels are lowered and the expression of tissue GLUT4 protein is up-regulated.

  12. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus

    Science.gov (United States)

    Rey-Burusco, M. Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R.; Roe, Andrew J.; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W.; Córsico, Betina; Smith, Brian O.

    2015-01-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein–ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male. PMID:26318523

  13. Circulating lipocalin-2 and retinol-binding protein 4 are associated with intima-media thickness and subclinical atherosclerosis in patients with type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Yang Xiao

    Full Text Available BACKGROUND: The lipocalin family proteins, including lipocalin-2 and retinol-binding protein 4 (RBP4, are adipokines closely associated with obesity-related metabolic disorders. In this study, we evaluated the association of serum lipocalin-2 and RBP4 with intima-media thickness (IMT and subclinical atherosclerosis in type 2 diabetic patients. METHODS AND RESULTS: Serum levels of lipocalin-2 and RBP4 were measured in 284 type 2 diabetic patients. Subclinical atherosclerosis was assessed by IMT at carotid, femoral and iliac arteries with ultrasound. Patients with subclinical atherosclerosis showed significantly higher circulating concentrations of lipocalin-2 and RBP4 when compared to those without [112.9 (86.4 to 202.1 µg/L versus 77.2(55.0-150.4 µg/L, 37.1(32.3-40.8 mg/L versus 23.2(20.1-29.2 mg/L, respectively; P = 0.002, P<0.001, respectively]. Moreover, positive correlations were observed between carotid IMT and lipocalin-2 (r = 0.170, P = 0.018 or RBP4 (r = 0.132, P = 0.040, femoral IMT and lipocalin-2 (r = 0.160, P = 0.027, as well as between iliac IMT and RBP4 (r = 0.241, P<0.001. Multiple logistic regression analysis further demonstrated that these two adipokines were independent risk factors for subclinical atherosclerosis in type 2 diabetes. CONCLUSION: Circulating levels of lipocalin-2 and RBP4 are positively correlated with carotid IMT and subclinical atherosclerosis in type 2 diabetes, which suggests a potential role of these two lipid-binding chaperones in the pathogenesis of vascular complications of diabetes.

  14. Retinol binding protein 4 and retinol in steatotic and nonsteatotic rat livers in the setting of partial hepatectomy under ischemia/reperfusion.

    Science.gov (United States)

    Elias-Miró, Maria; Massip-Salcedo, Marta; Raila, Jens; Schweigert, Florian; Mendes-Braz, Mariana; Ramalho, Fernando; Jiménez-Castro, Mónica B; Casillas-Ramírez, Araní; Bermudo, Raquel; Rimola, Antoni; Rodes, Juan; Peralta, Carmen

    2012-10-01

    Steatotic livers show increased hepatic damage and impaired regeneration after partial hepatectomy (PH) under ischemia/reperfusion (I/R), which is commonly applied in clinical practice to reduce bleeding. The known function of retinol-binding protein 4 (RBP4) is to transport retinol in the circulation. We examined whether modulating RBP4 and/or retinol could protect steatotic and nonsteatotic livers in the setting of PH under I/R. Steatotic and nonsteatotic livers from Zucker rats were subjected to PH (70%) with 60 minutes of ischemia. RBP4 and retinol levels were measured and altered pharmacologically, and their effects on hepatic damage and regeneration were studied after reperfusion. Decreased RBP4 levels were observed in both liver types, whereas retinol levels were reduced only in steatotic livers. RBP4 administration exacerbated the negative consequences of liver surgery with respect to damage and liver regeneration in both liver types. RBP4 affected the mobilization of retinol from steatotic livers, and this revealed actions of RBP4 independent of simple retinol transport. The injurious effects of RBP4 were not due to changes in retinol levels. Treatment with retinol was effective only for steatotic livers. Indeed, retinol increased hepatic injury and impaired liver regeneration in nonsteatotic livers. In steatotic livers, retinol reduced damage and improved regeneration after surgery. These benefits of retinol were associated with a reduced accumulation of hepatocellular fat. Thus, strategies based on modulating RBP4 could be ineffective and possibly even harmful in both liver types in the setting of PH under I/R. In terms of clinical applications, a retinol pretreatment might open new avenues for liver surgery that specifically benefit the steatotic liver.

  15. Fatty acid-and retinol-binding protein, Mj-FAR-1 induces tomato host susceptibility to root-knot nematodes.

    Directory of Open Access Journals (Sweden)

    Ionit Iberkleid

    Full Text Available Plant-parasitic nematodes produce at least one structurally unique class of small helix-rich retinol- and fatty-acid-binding proteins that have no counterparts in their plant hosts. Herein we describe a protein of the plant-parasitic root-knot nematode Meloidogyne javanica, which is a member of the nematode-specific fatty-acid- and retinol-binding (Mj-FAR-1 family of proteins. The mj-far-1 mRNA was detected through M. javanica pre-parasitic J2s, migratory and sedentary parasitic stages by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR. Immunolocalization assays demonstrate that the FAR protein of Meloidogyne is secreted during sedentary stages, as evidenced by the accumulation of FAR at the nematode cuticle surface and along the adjacent host root tissues. Tomato roots constitutively expressing mj-far-1 demonstrated an increased susceptibility to root-knot nematodes infection as observed by accelerated gall induction and expansion, accompanied by a higher percentage of nematodes developing into mature females compared to control roots. RNA interference assays that expressed double-stranded RNA complementary to mj-far-1 in transgenic tomato lines specifically reduced nematode infection levels. Histological analysis of nematode-infested roots indicated that in roots overexpressing mj-far-1, galls contained larger feeding cells and might support a faster nematode development and maturation. Roots overexpressing mj-far-1 suppressed jasmonic acid responsive genes such as the proteinase inhibitor (Pin2 and γ-thionin, illustrating the possible role of Mj-FAR-1 in manipulating the lipid based signaling in planta. This data, suggests that Meloidogyne FAR might have a strategic function during the interaction of the nematode with its plant host. Our study present the first demonstration of an in planta functional characterization and localization of FAR proteins secreted by plant-parasitic nematodes. It provides evidence that Mj

  16. Investigation of the relationship between retinol binding protein 4 and polycystic ovary syndrome metabolic disorder%视黄醇结合蛋白4与多囊卵巢综合征代谢紊乱的关系

    Institute of Scientific and Technical Information of China (English)

    阴红; 覃秀

    2014-01-01

    目的:探讨多囊卵巢综合征(PCOS)患者血清视黄醇结合蛋白4水平及与代谢紊乱的关系。方法:选择PCOS患者76例及同期就诊的40例健康志愿者及输卵管性不孕患者。根据体重指数(BMI)和年龄分为28例育龄期肥胖PCOS患者(年龄>19岁,BMI≥25 kg/m2),22例青春期肥胖PCOS患者(年龄≤19岁,BMI≥25 kg/m2),14例育龄期非肥胖PCOS患者(年龄>19岁,BMI<25 kg/m2),12例青春期非肥胖PCOS患者(年龄≤19岁,BMI<25 kg/m2),28例育龄期对照组,12例青春期对照组。检测血脂、葡萄糖耐量及胰岛素释放试验。视黄醇结合蛋白4水平采用酶联免疫吸附法测定。结果:育龄期PCOS肥胖患者视黄醇结合蛋白4血清水平高于对照组,差异有统计学意义。相关性分析显示,视黄醇结合蛋白4血清水平与甘油三酯呈正相关。结论:视黄醇结合蛋白4与PCOS脂代谢紊乱相关,但与胰岛素抵抗无相关性。%Objective:To explore the relationship between retinol binding protein 4 and metabolic disorder in patients with polycystic ovary syndrome.Methods:76 PCOS cases were selected.40 healthy volunteers and patients with tubal infertility were selected over the same period.According to BMI and age,they were divided into 28 cases of reproductive period obese PCOS patients(age>19 years old, BMI≥25 kg/m2),22 cases of adolescent obesity PCOS patients(BMI≥25 kg/m2,age≤19 years),14 cases of childbearing age non obese PCOS patients(age>19 years, BMI<25 kg/m2),12 adolescent with non obese PCOS patients(age<19 years,BMI<25 kg/m2),28 cases of childbearing age in control group,12 cases of adolescent control group.We detected blood lipid,glucose tolerance test and insulin release test.The retinol binding protein 4 level was measured by enzyme linked immunosorbent assay retinol binding protein.Results:In the retinol binding protein 4 level,PCOS obese patients of reproductive ages was higher than that in the

  17. Associations between retinol-binding protein 4 and cardiometabolic risk factors and subclinical atherosclerosis in recently postmenopausal women: cross-sectional analyses from the KEEPS study

    Directory of Open Access Journals (Sweden)

    Huang Gary

    2012-07-01

    Full Text Available Abstract Background The published literature regarding the relationships between retinol-binding protein 4 (RBP4 and cardiometabolic risk factors and subclinical atherosclerosis is conflicting, likely due, in part, to limitations of frequently used RBP4 assays. Prior large studies have not utilized the gold-standard western blot analysis of RBP4 levels. Methods Full-length serum RBP4 levels were measured by western blot in 709 postmenopausal women screened for the Kronos Early Estrogen Prevention Study. Cross-sectional analyses related RBP4 levels to cardiometabolic risk factors, carotid artery intima-media thickness (CIMT, and coronary artery calcification (CAC. Results The mean age of women was 52.9 (± 2.6 years, and the median RBP4 level was 49.0 (interquartile range 36.9-61.5 μg/mL. Higher RBP4 levels were weakly associated with higher triglycerides (age, race, and smoking-adjusted partial Spearman correlation coefficient = 0.10; P = 0.01, but were unrelated to blood pressure, cholesterol, C-reactive protein, glucose, insulin, and CIMT levels (all partial Spearman correlation coefficients ≤0.06, P > 0.05. Results suggested a curvilinear association between RBP4 levels and CAC, with women in the bottom and upper quartiles of RBP4 having higher odds of CAC (odds ratio [95% confidence interval] 2.10 [1.07-4.09], 2.00 [1.02-3.92], 1.64 [0.82-3.27] for the 1st, 3rd, and 4th RBP4 quartiles vs. the 2nd quartile. However, a squared RBP4 term in regression modeling was non-significant (P = 0.10. Conclusions In these healthy, recently postmenopausal women, higher RBP4 levels were weakly associated with elevations in triglycerides and with CAC, but not with other risk factors or CIMT. These data using the gold standard of RBP4 methodology only weakly support the possibility that perturbations in RBP4 homeostasis may be an additional risk factor for subclinical coronary atherosclerosis. Trial registration ClinicalTrials.gov number NCT

  18. 视黄醇结合蛋白在肾脏疾病中的诊断意义%Serum retinol binding protein levels in renal diseases

    Institute of Scientific and Technical Information of China (English)

    高婵; 王鸣; 费晓; 徐群红; 赵宁

    2014-01-01

    Objective To investigate serum retinol binding protein (RBP) levels in renal diseases. Methods Serum RBP, creatinine,urea,albumin, parathyroid hormone(PTH),β2 microglobulin were determined in 167 patients with renal disease. Results The serum creatinine, urea, PTH, RBP and β2 microglobulin levels were increased with the decreasing glomerular filtration rate (GFR). When GFR was lower than 60 ml/ (min·1.73m2), there were significant differences in serum RBP, creatinine and β2 mi-croglobulin levels between patients and controls. RBP levels were positively correlated with creatinine, urea, PTH and β2 mi-croglobulin(P<0.05);negatively correlated with endogenous creatinine clearance rate (Ccr) (P<0.05). Conclusion Serum RBP levels are increased in renal diseases, which may indicate the degree of severity of renal impairment in patients with nephropathy.%目的:探讨视黄醇结合蛋白(RBP)检测在肾脏疾病中的诊断意义。方法检测167例肾病患者和57例健康体检者的血清RBP、尿素氮、肌酐、血白蛋白、甲状旁腺素(PTH)、β2微球蛋白,计算肌酐清除率,探讨RBP与传统肾功能指标的关系以及其在诊断肾脏疾病中的临床意义。结果随肾小球滤过率(GFR)降低,尿素氮、肌酐、RBP、PTH、β2微球蛋白水平逐渐增高,当GFR<60ml/(min·1.73m2)时,肌酐、RBP、β2微球蛋白水平较对照组明显增高(P<0.05);RBP与肌酐、尿素氮、PTH、β2微球蛋白呈正相关(P<0.05),与内生肌酐清除率呈负相关(P<0.05)。随着肾功能逐渐下降,血RBP检测阳性率逐渐增高。结论 RBP是可作为早期诊断肾脏疾病的重要指标。

  19. Effect of 7-Hydroxy-2-(4-Hydroxy-3-Methoxy-Phenyl-Chroman-4-One (Swietenia Macrophylla King Seed on Retinol Binding Protein-4 and Phosphoenolpyruvate Carboxykinase Gene Expression in Type 2 Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Prasetyastuti

    2016-09-01

    Full Text Available Background and Aims: Diabetes mellitus is a metabolic disorder characterized by hyperglycemia due to a defect of insulin secretion, insulin action, or both. There are increasing evidence that active compounds of medicinal plants may be used to treat diabetes. The aim of this study is to investigate the effect of a 7-hydroxy-2-(4-hydroxy-3-methoxy-phenyl-chroman-4-one flavonoid compound of the Swietenia macrophylla King seed on homeostatic model assessment of insulin resistance (HOMA-IR, phosphoenolpyruvate carboxykinase (PEPCK and retinol binding protein-4 (RBP4 gene expression in diabetic rats.

  20. The threshold level of urinary cadmium associated with increased urinary excretion of retinol-binding protein and β2-microglobulin: a re-assessment in a large cohort of nickel-cadmium battery workers

    OpenAIRE

    2010-01-01

    OBJECTIVE: To evaluate the threshold value of urinary cadmium (CdU) for renal dysfunction on the basis of relationships unconfounded by protein degradation, diuresis and the renal effects associated with chronic smoking. Methods We studied 599 workers (451 men, mean age 45.4 years) who were employed in four nickel-cadmium battery plants for 18.8 years on average. After adjustment for covariates by multiple regression, the CdU threshold values for increased concentrations of retinol-binding pr...

  1. 尿β2MG、RBP水平与重金属中毒分析%Analysis of Urinary β2-microglobulin,Retinol Binding Protein Levels and Heavy Metal Poisoning

    Institute of Scientific and Technical Information of China (English)

    袁华敏; 李毅刚; 丁献山

    2011-01-01

    目的 探讨重金属中毒病人尿中β2微球蛋白(β2MG)、视黄醇结合蛋白(RBP)之间相关性.方法 回顾分析本院收治73例重金属中毒病例的尿β2MG、RBP同时升高的资料,用SPSS17.0对其进行了直线相关性分析.结果 73例中毒病例,尿镉高者占76.7%,镉中毒者占6.8%,镉观察对象占2.7%,铅中毒者占9.7%,砷中毒者占4.1%;尿β2MG与RBP之间r=-0.018(P>0.05);RBP女性高于男性(P<0.05).结论 尿β2MG、RBP在镉超标中常见,但不具有直线相关性.%Objective To explore the correlation between β2 microglobulin and retinoid binding protein in heavy metal poisoning patient's urine. Methods The data about simultaneously elevated levels of β2 microglobulin and retinoid binding protein of 73 heavy metal poisoning patients were retrospectively analyzed, and SPSS17.0 software was used to conduct linear correlation analysis. Results Among 73 patients, there were 76.7% of higher urinary cadmium, 6.8 % of cadmium poisoning, 2.7% of cadmium observed objects, 9.7% of lead poisoning, and 4.1% of arsenic poisoning. The coefficient r of linear correlation between β2 microglobulin and retinol binding protein was -0.018 (P>0.05). Retinol binding protein in women was higher than that of men (P < 0.05). Conclusions Elevated levels of urinary β2 - microglobulin and retinol binding protein are common in patients with excessive cadmium, but there is no linear correlation between them.

  2. 视黄醇结合蛋白4与2型糖尿病微血管病变的研究进展%Relationship between Retinol Binding Protein 4 and Microvascular Complication of Type2 Diabetes Mellitus

    Institute of Scientific and Technical Information of China (English)

    程灿; 赵芳芳; 王季猛

    2011-01-01

    视黄醇结合蛋白4(Retinol binding protein 4,RBP4)是一种分泌型视黄醇结合蛋白,主要由肝脏合成,在协助视黄醇发挥生理功能中起着重要的作用.近年研究发现,RBP4是一种新的循环性脂肪因子,亦能由脂肪组织特异性分泌,它不仅能够抑制肌肉组织中的胰岛素信号通路,而且能够促进糖异生,增加肝糖输出,从而导致胰岛素抵抗的发生,增加糖尿病的发病风险.目前RBP4与2型糖尿病(Type 2 diabetes mellitus,T2DM)关系逐渐受到人们的重视,本文就RBP4的生理功能、RBP4与T2DM微血管病变的研究进展作一综述.%Retinol binding protein 4 (RBP4) is a kind of secretion of retinol binding protein,mainly synthesized by the liver. It plays an important role in assisting the physiological function of retinol. In recent years, the studies have found RBP4 is a new kind of circulating adipocytokine, and can be specific secreted by the adipose tissues. It can not only inhibit the insulin signaling pathway of muscle tissue, but also promote gluconeogenesis and increase the glycogen output of liver, thus lead to insulin resistance, increases the morbidity of diabetes. Currently, the relationship between RBP4 and type 2 diabetes mellitus (T2DM)has been paid gradually attention by many scholars. This article describes the function of RBP4, review the relationship between RBP4 and micro-vascular complication with T2DM.

  3. 血清视黄醇结合蛋白4在危重患者急性肾功能障碍监测中的应用%Application of serum retinol binding protein 4 in the monitoring critically ill patients with acute renal dysfunction

    Institute of Scientific and Technical Information of China (English)

    喻红波; 刘阳; 张强; 李刚

    2011-01-01

    [Objective] To investigate the clinical value of serum retinol binding protein 4 in the monitoring acute renal dysfunction critically ill patients. [Methods] Serum retinol binding protein 4, creatinine and renal creatinine clearance level were determined in 72 critically ill patients, and their difference was analyzed. [Results] The levels of serum retinol binding protein 4 and creatinine clearance rate was negatively correlated, and serum retinol binding protein-4 correlated better with GFR than creatinine. The detection rate of acute renal dysfunction by serum retinol binding protein 4 (28/38) was higher than that of serum creatinine (8/38), the difference was statistically significant. [Conclusion] Retinol binding protein 4 is an accurate marker of subtle changes in GFR, and may be superior to creatinine when assessing this parameter in clinical practice in critically ill patients. The analysis of serum retinol binding protein 4 in critically ill patients may be helpful for the monitoring of acute renal dysfunction.%[目的]探讨视黄醇结合蛋白4在危重患者急性肾功能障碍监测中的应用.[方法]测定72例危重患者视黄醇结合蛋白4,肌酐及肾脏内生肌酐清除率水平,并分析其差异.[结果]危重患者视黄醇结合蛋白4水平与肾脏内生肌酐清除率水平明显负相关,且高于血清肌酐.在急性肾功能障碍检出率上,视黄醇结合蛋白4(28/38)高于血清肌酐(8/38),差异有统计学意义.[结论]视黄醇结合蛋白4是较精准的肾小球滤过率监测指标,可用于危重患者急性肾功能障碍的监测.

  4. Retinol binding protein detecing level analysis in diabetic nephropathy patients%糖尿病肾病患者视黄醇结合蛋白检测水平分析

    Institute of Scientific and Technical Information of China (English)

    何霞

    2014-01-01

    Objective:To analysis the of retinol binding protein (Retinol Binding Protein RBP) level in patients with diabetic nephropathy (Diabetic nephropathy, DN)) for the value of early diagnosis of kidney injury. Methods:In the Hitachi 7180 automatic biochemical analyzer (divided into DM group, DN group, DN group, early clinical) in patients with DN (experimental group) 87 cases were detected and 80 healthy subjects (control group) and serum RBP (SRBP) and urine RBP (URBP) level, while the conventional detection of serum indexes of microalbuminuria (mAlb), urea (UREA) and creatinine (CREA) levels were detected, and the detection results were compared statistically analysis.Results:The experimental group SRBP, URBP, mAlb, UREA and CREA levels were higher than those in the control group (P0.05);the early DN group:SRBP and URBP were significantly higher than those in the control group (p 0.05); clinical stage DN group: SRBP, URBP and mAlb were significantly higher than those in the control group (p<0.01), UREA and CREA higher than that of the control group (P<0.05). Conclusions:RBP testing can be used as a sensitive index of early renal damage in DN, monitoring of RBP levels with DN patients than hematuria, monitoring of mAlb, UREA and CREA levels can reflect the condition of earlier renal tubular injury, in order to achieve the goal of early diagnosis.%目的:分析视黄醇结合蛋白(Retinol Binding Protein RBP)水平在糖尿病肾病(Diabetic nephropathy, DN))早期肾损伤诊断中的应用价值。方法:在日立7180全自动生化分析仪上检测87例(分为单纯DM组、早期DN组、临床DN组)DN患者(实验组)及80例健康者(对照组)血清RBP(SRBP)和尿液RBP(URBP)水平,同时对常规检测指标血清尿微量白蛋白(mAlb)、尿素(UREA)和肌酐(CREA)的水平检测,并对其检测结果进行比较统计学分析。结果:实验组SRBP、URBP、mAlb、UREA和CREA水平均高于对照组(P<0.05或P<0.01

  5. The Evaluation of Early Diagnosis on Diabetic Nephropathies with Cystatin C and Retinol Binding Protein%血清CysC和RBP联检对糖尿病患者肾损害早期诊断的价值

    Institute of Scientific and Technical Information of China (English)

    黄璇; 周红英

    2011-01-01

    目的:探讨血清半胱氨酸蛋白酶抑制剂C(cystatin C,Cys C)和视黄醇结合蛋白(retinol binding protein,RBP)联检对诊断2型糖尿病(DM2)患者肾损害早期的临床价值.方法:选择91例DM2患者,采用乳胶颗粒增强免疫比浊法检测血清Cys C,免疫透射比浊法检测血清RBP,酶法检测血清BUN、SCr的含量,与44例健康体检者(健康对照组)进行对照比较.结果:患者血清Cys C、RBP、BUN和SCr水平均高于对照组,联检Cys C、RBP的阳性率明显高于单项.结论:血清Cys C和RBP是DM2患者早期肾损害的良好指标,联检可提供较新的概念,有助于对患者肾脏损伤的早期诊断和疗效观察.%Objective To observe the clinical significance of detaimination of serum cystain C ( Cys C) and retinol binding protein(RBP) levels in diagnosis of early renal damage in patients with type 2 diabetes . Methods Serum Cys C and RBP levels were detected in 91 patients with type 2 diabetes and 44 normal controls; BUN and SCr were measured simultaneously. Cys C and RBP were determined with immunoturbidimetric assay; Besides; BUN and SCr with enzyme method. Results Serum Cys C; RBP; BUN and SCr levels in patients with type 2 diabetes group were increased significantly compared with those in control group ( Cys C; RBP P < 0. 015 BUN; SCr P < 0.05) . The combined examination of Cys C and RBP showed that the sensitivity was 62. 6%; it's evidently higher than one of them. Conclusion Cys C and RBP are good diagnostic marker of early renal damage in patients with type 2 diabetes. The combined examination of Cys C and RBP may provide new ideas and can be more helpful for the diagnosis of early renal damage in patients with type 2 diabetes and observing curative effect.

  6. High dietary fat-induced obesity in Wistar rats and type 2 diabetes in nonobese Goto-Kakizaki rats differentially affect retinol binding protein 4 expression and vitamin A metabolism.

    Science.gov (United States)

    Shirai, Tomomi; Shichi, Yuta; Sato, Miyuki; Tanioka, Yuri; Furusho, Tadasu; Ota, Toru; Tadokoro, Tadahiro; Suzuki, Tsukasa; Kobayashi, Ken-Ichi; Yamamoto, Yuji

    2016-03-01

    Obesity is a major risk factor for type 2 diabetes, which is caused mainly by insulin resistance. Retinol binding protein 4 (RBP4) is the only specific transport protein for retinol in the serum. RBP4 level is increased in the diabetic state and high-fat condition, indicating that retinol metabolism may be affected under these conditions. However, the precise effect of diabetes and high fat-induced obesity on retinol metabolism is unknown. In this study, we examined differences in retinol metabolite levels in rat models of diet-induced obesity and type 2 diabetes (Goto-Kakizaki [GK] rat). Four-week-old male Wistar and GK rats were given either a control diet (AIN-93G) or a high-fat diet (HFD, 40% fat kJ). After 15 weeks of feeding, the RBP4 levels increased by 2-fold in the serum of GK rats but not HFD-fed rats. The hepatic retinol concentration of HFD-fed rats was approximately 50% that of the controls (P retinol concentrations of GK rats increased by 70% (P retinol metabolism differently, and the effects were different in different peripheral tissues. The impact of HFD may be limited to the storage of hepatic vitamin A as retinyl palmitate. In particular, our data indicate that renal retinoic acid production might represent an important target for the treatment of type 2 diabetes mellitus.

  7. Value of retinol binding protein and prealbumin in the evaluation of preterm infant nutrition%视黄醇结合蛋白和前白蛋白评价早产儿营养状况的价值

    Institute of Scientific and Technical Information of China (English)

    谢金水; 徐燕珊; 黄妙霞

    2015-01-01

    Objective To investigate the value of retinol binding protein and prealbumin in the evaluation of preterm infant nutrition. Methods Ninety-eight premature infants were selected in our hospital as the observation group, and at the same time, 98 full-term infants were selected in our hospital as the control group. According to gesta-tional age difference, the 98 premature infants were divided into group A (53 neonates with gestational age<34 weeks) and group B (45 neonates with gestational age≥34 weeks). The level of prealbumin and retinol binding protein, se-rum albumin of all newborns were detected and compared. Results The level of serum albumin, prealbumin, retinol binding protein in the observation group was (30.13±3.84) g/L, (23.91±3.93) mg/L, (122.83±24.47) mg/L, respective-ly, which were all significantly lower than the corresponding index in the control group (P<0.05). The level of the three proteins in group A was (29.06±5.28) g/L, (19.89±5.91) mg/L, (110.08±21.14) mg/L, respectively, significantly lower than the corresponding index of group B (P<0.05). Conclusion The detection of prealbumin and retinol bind-ing protein can more accurately, sensitively reflect the nutritional status in premature infants, which can provide basis for clinical nutrition support therapy.%目的:探讨视黄醇结合蛋白和前白蛋白评价早产儿营养状况的价值。方法选取在我院分娩的早产儿98例为观察组,同时选取同期在我院分娩的足月儿98例为对照组,并根据观察组新生儿胎龄的不同将胎龄<34周的53例新生儿分为A组,胎龄≥34周的45例新生儿分为B组。所有新生儿均检测血清白蛋白、前白蛋白和视黄醇结合蛋白的水平,对比观察组和对照组,A组和B组新生儿的血清白蛋白、前白蛋白和视黄醇结合蛋白的水平。结果观察组的血清白蛋白水平为(30.13±3.84) g/L,前白蛋白水平为(23.91±3.93) mg/L,视黄醇结合蛋白水平为(122

  8. Male mice are susceptible to high fat diet-induced hyperglycaemia and display increased circulatory retinol binding protein 4 (RBP4) levels and its expression in visceral adipose depots.

    Science.gov (United States)

    Asha, G V; Raja Gopal Reddy, M; Mahesh, M; Vajreswari, A; Jeyakumar, S M

    2016-01-01

    Vitamin A and its metabolites are known to modulate adipose tissue development and its associated complications. Here, we assessed the vitamin A status and its metabolic pathway gene expression in relation to sexual dimorphism by employing 35 days old C57BL/6J male and female mice, which were fed either stock or high fat (HF) diet for 26 weeks. HF diet feeding increased body weight/weight gain and white adipose tissue (WAT) of visceral and subcutaneous regions, however, increase in vitamin A levels observed only in subcutaneous WAT. Further, the expression of most of the vitamin A metabolic pathway genes showed no sexual dimorphism. The observed HF diet-induced hyperglycaemia in male corroborates with increased retinol binding protein 4 (RBP4) levels in plasma and its expression in visceral adipose depots. In conclusion, the male mice are susceptible to high fat diet-induced hyperglycaemia and display higher plasma RBP4 levels, possibly due to its over-expression in visceral adipose depots.

  9. 血清胱抑素c与视黄醇结合蛋白检测在糖尿病肾病早期诊断中的应用价值%Value of Serum Cystatin C and retinol-binding protein in early diagnosis of diabetic nephropathy

    Institute of Scientific and Technical Information of China (English)

    赵靓

    2010-01-01

    目的 探讨血清胱抑素C(CysC)与血清视黄醇结合蛋白(RBP)检测在糖尿病肾病早期诊断中的意义.方法 采用免疫速率散射比浊法,检测50例2型糖尿病肾病患者的血清胱抑素C与血清视黄醇结合蛋白.同时,用酶法检测血清尿素(Urea)、血清肌酐(Cr).结果 糖尿病肾病组血清胱抑素C、血清视黄醇结合蛋白均显著高于正常对照组(P<0.01).结论 胱抑素C与视黄醇结合蛋白可作为诊断糖尿病早期肾损害的血清学指标.%Objective To explore the serum cystatin C (CysC)and serum retinol-binding protein (RBP) test in early diagnosis of diabetic nephropathy in significance.Methods Immunization rate nephelometry to detect 50 cases of type 2 diabetic nephropathy in patients with serum cystatin C and serum retinol-binding protein.At the same time,with enzymatic detection of serum urea(Urea),serum creatinine (Ct).Results The diabetic nephropathy serum cystatin C,serum retinol-binding protein,significantly higher than the normal control group (P < 0.01).Conclusion Cystatin C and retinol-binding protein can be used as an early diagnosis of diabetes,serum indicators of renal damage.

  10. Urinary {alpha}{sub 1}-microglobulin, {beta}{sub 2}-microglobulin, and retinol-binding protein levels in general populations in Japan with references to cadmium in urine, blood, and 24-hour food duplicates

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Masayuki; Moon, Chan-Seok; Zhang, Zuo-Wen [Kyoto Univ. (Japan)] [and others

    1995-07-01

    Possible cadmium (Cd) exposure-associated changes in urinary levels of low-molecular-weight proteins were studied in nonsmoking and nondrinking female members of the general Japanese population (378 subjects with no known occupational heavy metal exposure) who lived at 19 study sites (all without any known environmental heavy metal pollution) in 13 prefectures throughout Japan. The external Cd dose was evaluated in terms of daily Cd intake via food (Cd-F), whereas Cd levels in blood (Cd-B) and urine (Cd-U) were taken as internal dose indicators. When the subjects were classified according to Cd-F into three groups with {open_quotes}low{close_quotes} (20.4 {mu}g/day as a geometric mean of 97 women), {open_quotes}middle{close_quotes} (35.0 {mu}g/day, 120 women) and {open_quotes}high{close_quotes} (67.0 {mu}g/day, 66 women) exposure, both Cd-B and Cd-U increased in parallel with the changes in Cd-F. However, there were no dose-dependent changes in {beta}{sub 2}-microglobulin or retinol-binding protein levels in urine. {alpha}{sub 1}-Microglobulin levels appeared to increase, but the distribution of the cases above the two cutoff levels of 9.6 and 15.8 {mu}g/mg creatinine among the three Cd-F groups did not show any bias. Overall, it was concluded that there was no apparent Cd exposure-associated elevation in urinary low-molecular-weight protein levels in the study population. 41 refs., 2 figs., 7 tabs.

  11. Research of relationship between retinol binding protein 4 and cardiovascular disease%视黄醇结合蛋白4与心血管疾病关系的研究进展

    Institute of Scientific and Technical Information of China (English)

    黄瑄; 郑刚

    2016-01-01

    Retinol binding protein 4(RBP4)is a kind of lipophilic carrier protein ,and also a kind of small hydrophobic molecules-binding protein.Its function is transferring all kinds of active metabolite (retinol)from Vitamin A. Thus help the Vitamin A to play its chief physiological function. Many Clinical researches show that the RBP4 is related to many risk factors of cardiovascular disease such as the arteriosclerosis ,Insulin resistance ,disorders of lipid metabolism and obesity and is also some correlated to the cardiovascular disease including Hypertension and heart failure.So this article will summarize the structure and function of RBP4 and its related research in the field of cardiovascular disease.%视黄醇结合蛋白(RBP4)是一种亲脂载体蛋白,也是一种疏水小分子结合蛋白,在体内负责结合并转运维生素 A 的各种活性代谢物(视黄醇类),从而协助维生素 A 发挥其主要生理功能。临床多项研究显示 RBP4与动脉硬化、胰岛素抵抗、脂质代谢紊乱、肥胖等心血管危险因素密切相关,并且与心血管疾病如冠心病、高血压和心力衰竭的病理生理有一定相关性。本文将对 RBP4的结构功能及其在心血管疾病中的相关研究进展做一综述。

  12. The Relationship of Fetuin-A, Adiponectin, Retinol Binding Protein-4 (RBP-4 and High Sensitivity C-Reactive Protein (hsCRP with Insulin Resistance (HOMA-IR in Obese Non Diabetic Men

    Directory of Open Access Journals (Sweden)

    Imelda Novianti

    2012-04-01

    Full Text Available BACKGROUND: Central obesity is the accumulation of visceral (intra-abdominal fat and is strongly known to be associated with insulin resistance and type 2 diabetes mellitus (T2DM. Obesity can cause adipocyte hypertrophy that results in dysregulation of adipokine expression. The abnormal function of adipocytes may play an important role in the development of a chronic low-grade proinflammatory state associated with obesity. Adiponectin, retinol binding protein (RBP-4 and fetuin-A play a role in the pathophysiology of insulin resistance. Expression of fetuin-A is increased due to fat accumulation in the liver. Elevated concentration of fetuin-A in the circulation can impair insulin signaling in muscle and liver as well as suppress adiponectin secretion, although its molecular mechanism is still unclear. The aim of this study was to identify the relationship of fetuin-A, adiponectin, RBP-4 and hsCRP with insulin resistance in obese non diabetic men. METHODS: This was an observational study with a cross-sectional design. The study subjects were 64 men with non diabetic abdominal obesity, characterized by waist circumference of 98.47±5.88 cm and fasting blood glucose of 85.75±8.36 mg/dL. RESULTS: This study showed that fetuin-A was positively correlated with HOMA-IR in obese non diabetic men with insulin resistance (r=0.128; p=0.570, although not significant. Fetuin-A was found to be correlated with adiponectin, RBP-4 and hsCRP (r=0.150; p=0.233; r=0.050; p=0.711; r=-0.04; p=0.445, although not significant. CONCLUSIONS: The concentration of fetuin-A showed a tendency to be positively correlated with HOMA-IR and with RBP-4 in obese non diabetic men, although statistically not significant. The concentration of fetuin-A showed a tendency to be negatively correlated with adiponectin and hsCRP although statistically not significant. There was no interrelationship between fetuin-A, adiponectin, RBP-4, hsCRP and HOMA-IR. Elevated concentrations of fetuin

  13. Progress in Research of the Relationship between Retinol-binding Protein 4 and Pathological Pregnancy%视黄醇结合蛋白4在病理妊娠中的研究进展

    Institute of Scientific and Technical Information of China (English)

    董金华; 刘俊; 徐先明

    2011-01-01

    Retinol binding protein (RBP)4 is a newly discovered adipocytokine. It has been found that RBP4 level is closely linked to insulin resistance,glucose and lipid metabolism in both animal and human studies. With the development of insulin resistance and the disorder of glucose and lipid metabolism, RBP4 level rises. During pregnancy, maternal fet mass increase with varying degrees of insulin resistance, to physiological pregnancy, blood RBP4 level increases with the progress of pregnancy. Compared with normal pregnancy, RBP4 increased more significantly in gestational diabetes mellitus (GDM) patients. The elevated levels of RBP4 may be involved in GDM prognosis. Study found that early elevated RBP4 could predict the occurrence of GDM, and controlling the development of RBP4 levels may interfere with GDM. RBP4 level is increased in pregnancy induced hypertension. RBP4 level in cord blood is closely related to fetal growth, the level declines in small for gestational age children and increases in large for gestational age children. The relationship between RBP4 and preterm delivery is not clear. Study the mechanism of RBP4, may provide a new direction for the development and prevention of pathological pregnancy.%视黄醇结合蛋白4 (Retinol binding protein4,RBP4)是近年来新发现的一种脂肪细胞因子,在动物与人类的研究中均发现其与胰岛素抵抗的发生及糖、脂代谢的调节密切相关,随着机体胰岛素抵抗及糖脂代谢异常程度的增加,RBP4水平上升.在妊娠期,母体脂肪量增加并伴有不同程度的胰岛素抵抗.在正常妊娠时,RBP4随着妊娠的进展而升高,且与胰岛素抵抗程度增加相一致.与正常妊娠相比,妊娠期糖尿病(gestational diabetes mellitus,GDM)患者的RBP4升高更明显,且RBP4的升高水平与GDM预后相关.研究发现早期RBP4的升高可以预测GDM的发生,此外控制RBP4水平可能干预GDM发展.RBP4在妊娠期高血压疾病中升高;RBP4

  14. A evaluation and comparison of two different kinds of biochemical reagents of serum retinol-binding protein%两种血清视黄醇结合蛋白生化试剂的比较和评价

    Institute of Scientific and Technical Information of China (English)

    王芳芳; 刘玉梅; 李光迪; 尤崇革

    2010-01-01

    Objective The evaluation and comparison of two different kinds of serum retinol-binding protein(RBP)reagents in the same biochemical analyzer.Methods Use the reagents of Shanghai Beijia biochemical reagents company and Beijing Jiuqiang biochemical limited company for serum retinol-binding protein determination.Their accuracy,repeatability,sensitivity,linear range and interference are compared.Results The results of Gcell reagents and Beijia reagents were evaluated,which regression equation wasY=1.011X,r~2=0.9604 in the normal group and y=1.043 8X,r~2=0.9657 in the patient group;The CV%of high-level and low-level controls were 0.9%and 2.3 0A respectively.The CV% of patients was 1.3%,The results range in 0.35~25 mg/dL,the linear error was less than 10%.Conclusion The results of Gcell reagents and Shanghai Beijia reagents are comparable and Gcell reagents can be safely used in clinical analysis.%目的 观察两种不同的血清视黄醇结合蛋白(RBP)试剂在同一台生化分析仪上的检测结果是否具有可比性.方法 用两种试剂进行血清视黄醇结合蛋白测定,并对两种试剂的准确性、重复性、线性范围等结果进行了评价比较.结果 金斯尔试剂与北加试剂比较,两种试剂间健康对照组回归方程Y=1.011X、r~2=0.960 4,患者组回归方程Y=1.043 8X、r~2=0.965 7,r~2>0.95,测定高、低值质控品的相对偏差分别为-2.32%和-4.64%,其准确性偏差小于10%;高、低值质控品测定值的CV分别为0.9%和2.3%,患者标本测定值CV为1.3%,其重复性CV小于10%;在0.35~25 mg/Dl范围内,线性误差不超过10%.结论 北京九强公司的金斯尔血清视黄醇结合蛋白检测试剂与上海北加试剂其检测结果具有可比性,可用于临床血清视黄醇结合蛋白的测定.

  15. 随机尿、晨尿视黄醇结合蛋白对早期肾功能损伤的诊断价值%Random Urine, Urinary Retinol-binding Protein in Early Diagnosis of Renal Injury

    Institute of Scientific and Technical Information of China (English)

    袁育林; 覃桂芳; 农生洲; 杜武杰; 阳文辉; 赵红英

    2013-01-01

    目的:探究随机尿、晨尿视黄醇结合蛋白对早期肾功能损伤的诊断价值.方法:选取我院2011年8月-2012年9月收治的48例Ⅱ型糖尿病患者,按照随机数字表进行平均分组,随机尿组24例,选取任意时段尿液标本,晨尿组24例,选取清晨时段尿液标本.对两组患者尿液标本进行尿视黄醇结合蛋白(Urinary Retinol-binding Protein,U-RBP)、尿微量白蛋白(Urinary Microalbum, U-mAlb)及尿N-乙酰-β-D氨基葡萄糖苷酶(Urinary N-acetyl beta-D-Glucosaminidase,NAG)水平测定,进行相关性分析并观察两组诊断阳性率.结果:随机尿组U-RBP、U-mAlb及NAG分别为(1.7± 0.9) mg/L、(76.2± 41.5) mg/L及(41.2± 30.0) U/L;晨尿组U-RBP、U-mAlb及NAG分别为(3.6±1.2)mgL、(118.5±71.)mg/L及(116.5±71.9) U/L.两组患者尿液检测指标均高于正常值,且晨尿组指标较随机尿组更高,两组数据对比存在统计学差异;随机尿组U-RBP、U-mAlb及NAG阳性例数分别为12例、6例及4例,晨尿组U-RBP、U-mAlb及NAG阳性例数分别为17例、13例及11例,晨尿组U-RBP、U-mAlb及NAG阳性率均高于随机尿组,两组数据对比存在统计学差异;随机尿组U-RBP与肾损伤相关性r=0.532,P >0.05,无明显相关性;晨尿组U-RBP与肾损伤相关性r=0.867,P<0.01,呈高度正相关.结论:随机尿及晨尿均可指示患者肾损伤出现,但随机尿蛋白指标无法有效指示肾损伤程度,对早期肾功能损害确诊准确率有限,而晨尿尿蛋白正常排泄率更高,且能够有效指示肾损伤程度,适用于糖尿病早期肾功能损伤的诊断及监测.%Objective:To explore the random urine,urinary retinol binding protein for early diagnosis of renal injury.Methods:48 patients with type Ⅱ diabetes patients in our hospital from August 2011 to August 2012 were selected and divided into two groups on the basis of random table.Random urine group:24 cases,selected urine of any time; Urinary group:24 cases,selected urine in the

  16. 血清视黄醇结合蛋白4与2型糖尿病视网膜病变的相关性%Association of serum retinol binding protein 4 with diabetic retinopathy in type 2 diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    赵丽君; 王薇

    2013-01-01

    Objective: To investigate the association of retinol binding protein 4 ( RBP4) with type 2 diabetic retinopathy. Methods; Retrospective analysis on clinical parameter and biochemical indicators of 192 cases of type 2 diabetes mellitus and 59 cases of controls in physics examination center from September 2011 to June 2012. Results: Patients with retinopathy ( DR group ) and without retinopathy ( NDR group) were significantly higher in age, duration of diabetic , body mass index , waist hip ratio , systolic blood pressure , diastolic blood pressure , glycosylated hemoglobin A1c, fasting blood sugar , fasting insulin , HOMA-IR, total cholesterol, triglyceride , retinol binding protein 4, microalbuminuria and microalbuminuria/creatinine compared with object of controls (N group) ( P 0. 05 ) . The level of age , duration of diabetic , retinol binding protein 4 , microalbuminuria , microalbuminuria/creatinine ,HOMA-IR in DR group were significantly higher than those in NDR group ( P < 0. 05 ). Logistic regression analysis showed that age , duration of diabetes , retinol binding protein 4 , microalbuminuria/creatinine , HOMA-IR were independent risk factors , and diastolic blood pressure was a protective agent. Conclusion; The level of retinol binding protein 4, microalbuminuria , microalbuminuria/ creatinine ,HOMA-IR were remarkably increased in type 2 diabetes with retinopathy. retinol binding protein 4, microalbuminuria/creatinine, HOMA-IR in type 2 diabetic patients with retinopathy were independent risk factors .%目的:探讨血清视黄醇结合蛋白(RBP4)与2型糖尿病(T2DM)视网膜病变发生的相关性.方法:回顾性分析2011年9月至2012年6月间收治的192例T2DM患者(分为合并视网膜病变的DR组和未合并的NDR组)和体检中心59例正常糖调节者(N组)的临床资料和生化指标.结果:N组与NDR组及DR组相比,在年龄、病程、BMI、WHR、SBP、DBP、HbA1c、FBS、FINS、HOMA-IR、T-CH、TG、HDL-C、RBP4、mALB和尿A/C

  17. 妊高症早期肾损伤检测视黄醇结合蛋白浓度水平的意义%Significance of testing the retinol binding protein in the early kidney injury of the pregnancy-induced hypertenision syn-drome diagnosis

    Institute of Scientific and Technical Information of China (English)

    曹登成

    2015-01-01

    目的:探讨妊高症早期肾损伤检测视黄醇结合蛋白浓度水平的意义,为临床诊治提供依据。方法选择2011年2月-2013年10月确诊为妊高症的孕妇100例设为试验组,选择同期健康孕检妊娠者100例设为对照组,分别检测视黄醇结合蛋白和胱抑素 C 的浓度水平,对结果进行分析。结果试验组孕妇的视黄醇结合蛋白和胱抑素 C浓度水平明显高于对照组,差异显著(P <0.05),且随着患者病情的加重呈现递增的趋势;试验各组患者孕妇的视黄醇结合蛋白和胱抑素 C 的阳性检出率分别两两比较均无明显差异(P >0.05),且患者的视黄醇结合蛋白阳性检出率均超过85.0%;临床确诊结果与视黄醇结合蛋白检测结果的 Kappa 一致性分析得出 Kappa 值等于0.86。结论视黄醇结合蛋白是一种同胱抑素 C 一样对妊高症早期肾损伤具有诊断价值的有效指标,具有较高的灵敏度和临床符合性。%Objective To explore the application meaning of the early kidney injury of the Pregnancy-induced hyper-tension syndrome diagnosis by the retinol binding protein testing,and providing the basis for clinical diagnosis and treatment.Methods Choosing 100 cases of the Pregnancy-induced hypertension syndrome patients for the experimental group and 100 cases healthy check-upes for the control group,testing the retinol binding protein and Cystatin C,analy-zing the results.Results Compared with the control group,there were significantly increased of retinol binding protein and Cystatin Cof the experimental group (P 0.05),and the positive rate of the retinol binding protein of the experimental group was more than 85.00%.The Kappa of the retinol binding protein results and the clinical diagnosis was 0.86.Conclusion There is a good indicators of the retinol binding protein whcih as the Cystatin C for the early kidney injury of the Preg-nancy-induced hypertension syndrome

  18. Clinical value of detection of urinary retinol-binding protein for renal disease%尿视黄醇结合蛋白在肾脏病中的检测及评价

    Institute of Scientific and Technical Information of China (English)

    赖子飞

    2011-01-01

    目的 探讨尿液视黄醇结合蛋白(UrRBP)作为肾脏疾病患者肾小管功能损害的筛选指标及其在肾脏病诊断中的价值.方法 应用免疫透射比浊法对对照组和不同肾脏病组进行UrRBP测定.结果 不同肾脏病组的UrRBP值:肾病综合征组为(11.12±7.198) mg/L,肾小球肾炎组为(3.394+2.806) mg/L,糖尿病肾病组为(6.440±4.928) mg/L,狼疮性肾炎组为(9.982±6.818) mg/L,与对照组的(0.2915±0.061) mg/L比较,各肾脏病组与对照组差异有统计学意义(P<0.01).结论 UrRBP测定能放映出肾小管的损害程度,是检测肾小管功能损害的敏感指标.%Objective To investigate urinary retinol-binding protein (UrRBP) as the filter indicators for tubular function in patients with renal disease and its value in the diagnosis of renal disease. Methods Applying immunoturbidimetric assay, levels of UrRBP were detected in the control group and four groups of patients with different kinds of renal disease (nephritic syndrome group, glomerular nephritis group, diabetic nephropathy group, and lupus nephritis group). Results Levels of UrRBP for patients with nephritic syn drome, glomerular nephritis, diabetic nephopathy and lupus nephritis were (11.12±7.198) mg/L, (3.394± 2.806) mg/L, (6.440±4.928) mg/L and (9.982±6.818) mg/L, which showed statistically significant difference with that in the control group [(0.2915±0.061) mg/L]. Conclusion Level of UrRBP can reflect the degree of tu bular damage, serving as a sensitive index for evaluating renal disease.

  19. A study on correlation between retinol-binding protein 4 and atherosclerosis%视黄醇结合蛋白4与动脉粥样硬化关系的研究

    Institute of Scientific and Technical Information of China (English)

    高璐; 秦明照; 陈晓燕; 常志文

    2014-01-01

    目的探讨血浆视黄醇结合蛋白-4(RPB4)与动脉粥样硬化(AS)的关系。方法90例研究对象行颈动脉超声测量颈动脉内膜中层厚度(IMT),根据IMT<1.0mm与≥1.0mm分为IMT正常组和IMT增厚组,测定血浆RPB4水平。结果 IMT增厚组的总胆固醇( TC)、低密度脂蛋白胆固醇( LDL-C)、糖化血红蛋白(HbA1c)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)、高敏C反应蛋白(hsCRP)、RBP4及冠心病、2型糖尿病、脑动脉硬化患病率均显著高于IMT正常组,差异有显著性。相关分析显示血浆RBP4与腰围、体重指数、甘油三酯、TC、LDL-C、HbA1c、HOMA-IR、hsCRP、IMT呈正相关。结论血浆RBP4在AS的发生、发展过程中起到一定作用。%Objective To investigate the correlation between plasmal retinol-binding protein 4 ( RBP4 ) levels and atherosclerosis (AS). Method According to carotid intima-media thickness(IMT), 90 subjects were divided into two groups:the normal IMT group and the thickened IMT group. Plasmal RBP4 levels were measured by ELISA. Result Plasmal TC, LDL, HbA1c, FINS, HOMA-IR, hsCRP, RBP4 levels and the morbidity rate of coronary heart disease, type 2 diabetes mellitus and cerebral arteriosclerosis in the thickened IMT group was significantly higher than those in the normal IMT group, Plasmal RBP4 level was positively correlated with Waist, BMI, TC, TG, LDL, HbA1c, HOMA-IR, hsCRP, IMT. Conclusion Elevated RBP4 levels might affect the delevopment of AS.

  20. RELATIONSHIP BETWEEN RETINOL BINDING PROTEIN 4 AND INSULIN RESISTANCE IN GESTATIONAL DIABETES MELLITUS%血清RBP4与妊娠期糖尿病胰岛素抵抗关系

    Institute of Scientific and Technical Information of China (English)

    孙蕾芳; 叶元华

    2011-01-01

    目的 探讨血清视黄醇结合蛋白4(RBP4)水平与妊娠期糖尿病(GDM)胰岛素抵抗的关系.方法 采用酶联免疫吸附法测定了30例GDM病人(GDM组)及30例糖耐量正常孕妇(对照组)血清RBP4水平,葡萄糖氧化酶法检测空腹血糖(FPG),放射免疫法检测空腹胰岛素(FIN),计算胰岛素抵抗指数(HOMA-IR).结果 GDM组血清RBP4水平显著高于对照组(t=8.298,P<0.05).GDM组FPG、FIN及HOMA-IR水平明显高于对照组(t=7.259~16.409,P<0.05).GDM组血清RBP4水平与HOMA-IR呈明显正相关(r=0.744,P<0.05).结论 GDM病人血清RBP4水平升高,可能参与了糖尿病胰岛素抵抗的发生.%Objective To investigate the relationship between retinol binding protein 4 (RBP4) and insulin resistance in gestational diabetes mellitus (GDM).Methods The serum RBP4 levels were determined in 30 patients with GDM (GDM group) and 30 pregnant women with normal glucose tolerance (control group) by Enzyme-linked immunosorbent assay (ELISA).Fasting plasma glucose (FPG) and fasting insulin levels (FIN) were measured by glucose oxidaseand and radio immunity assay.Insulin resistance index (HOMA-IR) was calculated.Results The serum levels of RBP4 (t=8.298, P<0.05) and FPG, FIN and HOMA-IR were significantly higher in GDM group than the control (t= 7.259-16.409, P<0.05).There was a positive correlation between the levels of serum RBP4 and HOMA-IR (r=0.744,P<0.05).Conclusion The elevation of the levels of serum RBP4 in GDM patients is likely involved in the cause of insulin resistance in GDM.

  1. Detection and analysis of serum retinol binding protein in patients with different liver diseases%血清视黄醇结合蛋白在肝损伤中的意义

    Institute of Scientific and Technical Information of China (English)

    邵珺; 李平; 于乐成; 何长伦; 汪茂荣

    2015-01-01

    目的:探讨视黄醇结合蛋白(RBP)在不同临床类型肝损伤患者血清中的水平及临床意义。方法对370例肝病患者及50例健康对照者采用日立7600全自动生化分析仪分别测定 TBil、ALT、Alb 和 RBP,并进行统计分析。结果除脂肪肝组外,急性肝炎组、慢性肝炎组、药物性肝炎组、肝硬化组、自身免疫性肝炎组、肝癌组中 TBil、ALT 水平较对照组显著升高(P <0.05),Alb、RBP 水平较对照组显著降低(P <0.05)。RBP、Alb 降低具有一致性,在急性肝炎组、慢性肝炎组、药物性肝炎组、肝硬化组、肝癌组中的 RBP 异常率更高于 Alb 异常率(P <0.05)。结论RBP 检测可早期灵敏反映肝功能损伤情况,值得临床广泛使用。%Objective To investigate the levels and clinical significance of retinol binding protein (RBP)in patients with different clinical types of liver injury.Methods RBP,Total bilirubin (TB),alanine aminotransferase (ALT)and albumin (ALB)were detected and analyzed in 370 liver disease patients and 50 healthy person by Hitachi 7600 automatic biochemical analyzer.Results The TB,ALT levels were significantly higher,while the ALB and RBP levels in acute hepatitis,chronic hepatitis,drug-induced hepatitis,cirrhosis,autoimmune hepatitis,liver cancer group were significantly lower than those in control group (P <0.05),respectively.RBP declined consistently with ALB level.The abnormal rates of RBP were higher than those of ALB in acute hepatitis,chronic hepatitis,drug-induced hepatitis,cirrhosis and liver cancer groups (P <0.05),respectively.Conclusion RBP is a sensitive reflector of liver damage;it is helpful in the clinical application.

  2. Meta-analysis of Relationship Between Serum Levels of Retinol-binding Protein 4 and Diabetic Nephropathy%视黄醇结合蛋白4与糖尿病肾病关系的Meta分析

    Institute of Scientific and Technical Information of China (English)

    倪雅楠; 李强

    2015-01-01

    目的 为综合性地进一步探讨血清视黄醇结合蛋白4(retinol-binding protein 4,RBP4)水平与糖尿病肾病的相关性.方法 检索了所有RBP4与糖尿病肾病相关的已发表文献.文献来源PubMed、EMBASE、CINAHL、中国期刊全文数据库(CNKI)、中国生物医学文献数据库(CBM)和维普中文科技期刊数据库(VIP)等,共获得文献23篇,阅读文题和摘要排除文献5篇:其中非病例对照研究3篇、综述1篇、Meta分析1篇.阅读全文评估后,排除不满足纳入条件文献9篇:其中不可靠性发表4篇、分组不详文章1篇、RBP4与非糖尿病肾病相关性文章4篇,最终共纳入9项相关性研究.每一项研究均对每个变量,汇总相关系数(RS),使用随机效应荟萃分析估计.使用视黄醇结合蛋白4、2型糖尿病与糖尿病肾病作为关键词.提取相关数据并应用RevMan 5.0软件进行Meta分析.结果 共纳入725例研究对象,Meta分析结果显示2型糖尿病合并肾病组血清RBP4水平明显高于对照组,其差异有统计学意义[WMD =20.47 95%CI(11.90 29.04)P<0.00001].结论 视黄醇结合蛋白4水平与糖尿病肾病呈明显相关性.

  3. 对比分析视黄醇结合蛋白在高血压肾病早期检测的临床价值%To compare and analyse the clinical significance of the early diagnosis of the Hypertensive Renal Disease by the Retinol binding protein testing

    Institute of Scientific and Technical Information of China (English)

    丁峰

    2015-01-01

    Objective To analyse the clinical significance of the early diagnosis of the Hypertensive Renal Disease by the Retinol binding protein testing, in order to provide reference for clinic.Methods Choosing 113 samples of patients with Hypertensive Renal Disease for the experimental group, according to the course of hypertension can be divided into the first group of 40 patients, the second group of 36 patients and the third group of 37 patients, and choosing 40 samples of healthy for the control group,then all of them were testing the Retinol binding protein and the Cystatin C, and statistical analysis of data.Results Compared to the control group, there was obviously increased of the concentration level of the Retinol binding protein and the Cystatin C(P0.05) . The detection rate of the one phase group can be significantly improved than the single detection(P<0.05).Conclusions There is a certain clinical value of the Retinol binding protein detection for the patient monitoring, it can be effectively reduce the rate of missed diagnosis by jointing detection of the Retinol binding protein and the Cystatin C.%目的:探讨分析高血压肾病早期检测视黄醇结合蛋白的临床价值,为临床提供参考依据。方法:选择113例确诊为高血压肾病的患者设为试验组,根据高血压病程可分为一期组40人,二期组36人和三期组37人,选择同期体检健康者40人设为对照组,同时检测患者和对照者的血清视黄醇结合蛋白浓度水平和胱抑素C浓度水平,统计分析结果。结果:试验三个小组的患者视黄醇结合蛋白和胱抑素C浓度水平均明显高于对照组,差异有显著性(p<0.05),随着患者病程的增长,试验三个小组间的患者视黄醇结合蛋白和胱抑素C浓度水平呈现正相关升高(r=0.9997和r=0.9947);各组患者的视黄醇结合蛋白阳性检出率分别与对应组患者的胱抑素C阳性检出率两两比

  4. 血清视黄醇结合蛋白-4水平与胎儿宫内生长发育的关系%Relationship between serum retinol binding protein 4 level and fetal intrauterine growth and development

    Institute of Scientific and Technical Information of China (English)

    刘鹏; 张小莉

    2011-01-01

    目的:检测新生儿血清视黄醇结合蛋白-4(RBP-4)的水平,探讨其与胰岛素水平及胎儿宫内生长发育的关系,并对相关因素进行分析.方法:用酶联免疫法检测89例新生儿血清中RBP-4和胰岛素水平,其中小于胎龄组(SGA)30例、适于胎龄组(AGA)30例、大于胎龄组(LGA)29例,并按出生体重评估新生儿宫内的营养状态.结果:①3组间RBP-4及胰岛素水平的差异有统计学意义(P均<0.05).②血清RBP-4水平与新生儿出生体重呈明显正相关(r=0.943,P<0.01);③胰岛素水平与新生儿出生体重呈明显正相关(r=0.975,P<0.01);④RBP-4水平与胰岛素水平呈明显正相关(r=0.979,P<0.01).结论:新生儿体内RBP-4水平在一定程度上反映宫内牛长发育状态,可能和胰岛素共同参与调节新生儿的生长发育.%Objective: To detect the serum retinol binding protein 4 ( RBP -4) level in neonates, explore its relationship with insulin level and fetal intrauterine growth and development, and analyze the related factors.Methods: ELISA was used to detect the serum levels of RBP-4 and insulin in 89 neonates, 89 neonates included 30 neonates in small for gestational age (SGA) group, 30 neonates in appropriate for gestational age (AGA) group and 29 neonates in large for gestational age (LGA) group, then the intrauterine nutritional conditions of the neonates were assessed according to birth weight.Results: There was significant difference in serum levels of RBP -4 and insulin among the three groups ( P < 0.05 ).There was a significant positive correlation between serum RBP - 4 level and neonatal birth weight ( γ = 0.943, P < 0.05 ); there was a significant positive correlation between serum insulin level and neonatal birth weight ( γ = 0.975, P <0.05); there was a significant positive correlation between serum RBP - 4 level and serum insulin level ( γ = 0.979, P < 0.0l ).Conclusion: Neonatal RBP-4 level reflect the state of intrauterine growth and

  5. 视黄醇结合蛋白-4与冠心病及其危险因素的关系%The Relationship between Retinol Binding Protein - 4 and Coronary Heart Disease as well as Its Risk Factors

    Institute of Scientific and Technical Information of China (English)

    聂晨; 万月红; 丁进叶; 干学东; 龚斐; 任江华

    2015-01-01

    目的:探讨血清视黄醇结合蛋白-4(RBP -4)水平与冠心病及其危险因素的关系。方法收集2010~2011年在我院行冠脉造影术的患者400名,其中证实冠心病301例,正常组99例。运用酶联免疫吸附法检测所有患者的血清 RBP -4 水平,应用 SPSS 18.0进行数据分析。结果冠心病组血清 RBP -4 水平较正常组高(P ﹤0.01),TC 及 TG 水平与正常组差异无统计学意义。相关分析显示冠心病患者血清 RBP -4 水平与血清总胆固醇(TC)、甘油三酯(TG)、载脂蛋白 A1(ApoA1)、尿素氮(BUN)、尿酸(UA)呈正相关(相关系数分别为0.128、0.156、0.151、0.128、0.130,P 值均小于0.05)。与总胆红素(TBILI)和间接胆红素(IBI)呈负相关(相关系数分别为-0.117、-0.131,P 值均小于0.05)。结论血清 RBP -4 水平可能为独立于高脂血症的冠心病危险因素,有望成为预测冠心病的指标。%Objective To investigate the relationship between serum retinol binding protein - 4(RBP - 4)and coronary heart disease as well as its risk factors. Methods 400 patients underwent coronary angiography were in-volved in this study from 2010 to 2011,in whom 301 subjects were diagnosed as coronary heart disease(CHD)and 99 were normal. Serum RBP - 4 levels were measured by ELISA. SPSS18. 0 statistical software was used for data analy-sis. Results Serum RBP - 4 levels in patients with CHD were significantly higher than those in normal people(P ﹤0. 01). There was no significant difference in TC and TG between the two groups. RBP - 4 level was positively correla-ted with TC,TG,ApoA1,BUN and UA( Pearson coefficient of association were 0. 128,0. 156,0. 151,0. 128 and 0. 130,P ﹤ 0. 05),while negatively correlated with TBILI and IBI(Pearson coefficient of association were - 0. 117 and - 0. 131,P ﹤ 0. 05). Conclusion RBP - 4 level may be an independent risk factor to hyperlipidemia,and hope-fully become a new

  6. 血清视黄醇结合蛋白4与慢性乙肝的相关性分析%Relationship between Serum Retinol-Binding Protein4 and Chronic Hepatitis B

    Institute of Scientific and Technical Information of China (English)

    杨秋红; 刘海亮; 崔景利; 燕二相; 杨凤云

    2011-01-01

    目的:观察慢性乙肝患者血清视黄醇结合蛋白4(RBP4)、前白蛋白(PA)、血氨水平,分析RBP4与慢性乙肝的相关性.方法:采集90例慢性乙肝患者分为轻度组26例,中度组34例,重度组30例,另选择30例健康对照组.采用酶联免疫吸附法(ELISA)测定血清RBP4水平,采用免疫透射比浊法测定血清PA水平,用全自动生化分析仪测定血氨水平.结果:血清RBP4、PA在病例组中低于对照组,差异有统计学意义(P<0.05),血氨水平在病例组中高于对照组,差异有统计学意义(P<0.05).血清RBP4、PA、血氨水平在轻度、中度、重度组内比较P<0.05,有统计学意义.经Pearson's相关分析,血清RBP4与PA浓度呈显著正相关相关(r=0.896,P<0.01),与血氨浓度呈显著负相关(r=-0.781,P<0.01).结论:RBP4与慢性乙肝存在一定的相关性,与肝脏的损伤程度有关,可作为预测肝脏损伤的血清标志物.%Objective: To evaluate the correlation of Retinol binding protein 4 (RBP4) and the Chronic Hepatitis B by test the serum level of the RBP4, the prealbumin (PA) and the blood ammonia (BA).Methods: Ninety patients with Chronic Hepatitis B were divided into the mild group(n=26), the moderate group (n =34) and the severe group (n=30), 30 normal subjects without the Hepatitis B diagnosed by the laboratory examination served as the control group.The serum level of RBP4 is measured by enzyme linked immune sorbent assay (ELISA), while the PA is measured by turbidmetric immunoassay and the serum level of the BA is measured by the automatic biochemistry analyzer.Results: The serum level of RBP4 and PA were lower in the research group than the control group (P<0.05),but the blood ammonia is higher in the research group than the control group (P<0.05).The mean levels of RBP4、PA and BA among the mild, moderate and the severe group were significantly different (P<0.05).The serum level of RBP4 was significantly positive correlation with the PA (r=0

  7. Expression and the roles of serum retinol-binding protein 4 in acute stroke patients and the discussion on retinol-binding protein 4 and low density lipoprotein relationship%急性脑卒中患者血清视黄醇结合蛋白4的表达及其与低密度脂蛋白关系的探讨

    Institute of Scientific and Technical Information of China (English)

    王珊; 姚娟; 高小平

    2013-01-01

    Objective This study was performed to analysis the expression of serum retinol-binding protein 4 (RBP4) in acute stroke patients and discuss the relationship between serum RBP4 and low density lipoprotein level.Methods 81 patients of acute intracerebral hemorrhage(ICH) and 191 acute cerebral infarction(CI) patients who were in the Neurology department of Hunan Provincial People's Hospital were observed between June 2011 to June 2012.The control group includes 100 normal subjects in the mean time. All the Patients were tested their RBP4 and LDL. Compared the RBP4 level and LDL level of these three groups ,analysising the relationship be-tween these two indexes of each group. Results Compared with the control group, the levels of RBP4 and LDL of the acute Cerebral infarction (CI) group was significantly higher (P<0.001).The acute intracerebral hemorrhage (ICH) group was higher than control group too.(P<0.01).The linear correlation analysis revealed that the level of RBP4 in CI group with the level of LDL were positive correlated. (r=0.456,P<0.001).Conclusion Serum RBP4 is probably associated with the occurrence and the development of acute stroke. The level of RBP4 has a correlation with LDL in cerebral infarction group. It may become one of the important marks of the acute cerebral infarction, it also be helpful for the prediction and early diagnosis.%  目的:探讨急性症状性脑卒中患者血清视黄醇结合蛋白4(RBP4)的表达水平及其与低密度脂蛋白之间有无相关关系。方法:从本院选取2011年6月至2012年6月间住院的191例急性脑梗死患者,81例急性脑出血患者为观察组。以同期体检健康者100例为对照组。比较急性脑梗死组、急性脑出血组与对照组血清RBP4水平,低密度脂蛋白水平。分析视黄醇结合蛋白4与低密度脂蛋白的相关性。结果:与对照组相比,脑梗死组平均RBP4水平、LDL水平明显升高(P<0.001),脑出血组平均RBP4水

  8. Função renal de pacientes de unidade de terapia intensiva: creatinina plasmática e proteína carreadora do retinol urinário Renal function of intensive care unit patients: plasma creatinine and urinary retinol-binding protein

    Directory of Open Access Journals (Sweden)

    Cristina Satoko Mizoi

    2008-12-01

    ário. CONCLUSÃO: A proteina carreadora do retinol urinário, na prática clínica, pode ser considerada um marcador mais apropriado para o diagnóstico em pacientes com risco de desenvolver uma insuficiência renal aguda, quando comparada com outros marcadores usados rotineiramente. Ademais, a proteina carreadora do retinol urinário apresenta outros aspectos de um bom teste diagnóstico - é um método prático e não-invasivo.OBJECTIVES: The early assessment of renal dysfunction using common markers does not provide either a sensitive or specific indication of renal dysfunction in critically ill patients. More specific and sensitive markers are desirable for the early detection of an initial renal pathophysiological process. Urinary retinol-binding protein could be an alternative method to early evaluation of renal function in these patients. METHODS: This study followed-up 100 critical care patients and assessed their clinical and laboratory variables, including plasma creatinine and urinary retinol-binding ratio, and demographic variables. RESULTS: The sample was characterized by geriatric (63.4±15.6 years, male (68%, being 53% surgical patients. Statistical analysis showed association between plasma creatinine and the following variables: gender (p-0.026, age (p-0.038, use of vasoactive drugs (p-0.003, proteinuria (p-0.025, Acute Physiological Chronic Health Evaluation (APACHE II score (p-0.000, urea (p-0.000, potassium (p-0.003 and estimated creatinine clearance (p-0.000. Urinary retinol-binding protein was correlated with more variables: weight, use of invasive ventilation (p-0.000, use of nonsteroidal antiinflammatory drugs (p-0.018, use of vasoactive drugs (p-0.021, high temperature (>37.5ºC (p-0.005, proteinuria (p-0.000, bilirubinuria (p-0.004, urinary flow (p-0.019, minimal diastolic pressure (p-0.032, minimal systolic pressure (p-0.029, APACHE II (p-0.000, creatinine (p-0.001, urea (p-0.001, estimated creatinine clearance (p-0.000. Urinary retinol-binding protein

  9. The aging changes of the plasma retinol-binding protein 4 levels in elderly essential hypertension patients%老年高血压患者血浆视黄醇结合蛋白的增龄变化

    Institute of Scientific and Technical Information of China (English)

    曹萍; 李睿; 沈丹; 钟亚

    2011-01-01

    Objective To explore the aging changes of the plasma retinol-binding protein 4(RBP4)levels in elderly essential hypertension patients and to evaluate the influential factors. Methods 275 essential hypertension patients were divided into two groups according to whether complicated by type 2 diabetes mellitus. Fifty healthy persons served as normal control group. Plasma RBP4 levels were determined in the three groups. The relationships of plasma RBP4 levels with the blood pressure,the plasma lipids levels and body mass index were analyzed. The effect of aging in the 275 patients on the plasma RBP4 levels was explored. Results The plasma RBP4 levels were significantly increased both in the pure hypertension group and in the hypertension complicated by type 2 diabetes mellitus group compared with the control group (P<0.01), but there was no statistical difference between the pure hypertension group and the hypertension complicated by type 2 diabetes mellitus group. The level of plasma RBP4 was positively correlated with plasma triglyceride and low density lipoprotein-cholesterol (r = 0. 347, r = 0. 229, P < 0.01). However, the level of plasma RBP4 gradually decreased with age in all essential hypertension patients. The age was negatively correlated with the level of plasma RBP4, buttock circumference, body weight, body mass index, diastolic pressure,average arterial pressure, triglyceride and low density lipoprotein cholesterol (P < 0.01). Conclusion There is a phenomenon of insulin resistance which correlates with plasma RBP4 increase in the patients with essential hypertension. The level of plasma RBP4 gradually decreases with age in all essential hypertension patients. It is inferred that the insulin resistance plays a more important part in essential hypertension in young patients than in elderly patients.%目的 探讨老年高血压患者血浆视黄醇结合蛋白(retionl binding protein 4,RBP4)水平的增龄变化及其影响因素.方法 将275例高

  10. 视黄醇结合蛋白4与非酒精性脂肪肝病的相关研究%Relationship between serum retinol-binding protein 4 and non-alcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    刘滨菘; 李强; 王薇; 郭琳; 王晶; 刘姝; 张巾超

    2013-01-01

    ,blood lipid,liver function,kidney function,and serum retinol-binding protein 4 (RBP4) levels were determined.The risk of various indicators for NAFLD was determined by correlation analysis and logistic regression analysis.The results showed that fasting glucose levels in diabetics with or without NAFLD were significantly higher than those in NC and NAFLD groups(P<0.01).Triglyceride (TG) level in DMN group was significantly higher than those in other three groups(all P<0.01),while high density lipoprotein-cholesterol level was lower than those in other three groups(all P<0.01).Systolic blood pressure and diastolic blood pressure in DMN group were higher than those in NC and T2DM groups (P<0.05 or P<0.01).Serum RBP4 level in patients with NAFLD was significantly higher compared with the subjects without NAFLD [45.00 (38.75,51.00) mg/L vs 51.00 (43.00,62.00) mg/L,P <0.01],and was rising with the progress of NAFLD [NAFLD-L group 44.00 (37.00,51.00) mg/L,NAFLD-M group 52.00(46.00,63.00) mg/L,and NAFLD-S group 78.5 (72.75,83.00) mg/L,all P<0.01].Logistic regression analysis showed that the RBP4 level was an independent factor associated with NAFLD (P =0.029).In addition,serum RBP4 level was correlated with body mass index,waist-to-hip ratio,serum gamma-glutamyl transpeptidase,total cholesterol,TG,aspartate aminotransferase,alanine aminotransferase,prealbumin,creatinine,blood urea nitrogen,and uric acid.These resuhs suggest that serum RBP4 is an independent risk factor of NAFLD.

  11. Assessment of Retinol Binding Protein 4 in Nutritional Diseases and Liver or Kidney Diseases%视黄醇结合蛋白4检测在营养性疾病及肝肾损害检测中的临床应用

    Institute of Scientific and Technical Information of China (English)

    孟俊; 顾志冬; 陈呢喃; 张冬青

    2015-01-01

    视黄醇结合蛋白(retinol binding protein,RBP)是一种分泌型视黄醇结合蛋白,主要合成于肝脏,广泛分布于人体血液、尿液等体液中的视黄醇(VitA)运载蛋白,在协助 VitA发挥生理功能中起到关键作用[1]。最新研究表明:RBP4是一种新的脂肪细胞因子,参与胰岛素抵抗和2型糖尿病的发生,与糖尿病肾病、营养性疾病等的发展存在着一定的相关性。这一发现使得 RBP4更加受到人们的重视。该文就 RBP4的生理功能,在肝肾疾病、糖尿病等各类疾病方面的应用以及新型临床检测方法作一综述。%Retinol binding protein 4 (RBP4)was a class of secreting protein,mainly synthesized by the liver,widely distribu-ted in the human body blood,urine and other body fluids.It plays an important role in assisting the physiological function of vitamin A[1].Recent research shows that RBP4 was a new kind of adipocytokine,participated in insulin resistance and occur-rence of type 2 diabetes,and had a closed relationship with diabetic nephropathy,nutritional disease.This article describes the function of RBP4,review the relationship between RBP4 and nutritional or other type of diseases,and new clinical detec-tion method with RBP4.

  12. 非酒精性脂肪性肝病模型大鼠饮食或二甲双胍干预后肝视黄醇结合蛋白4表达%Effects of dietary interventionversus metformin treatment on retinol binding protein 4 expressions in rats with non-alcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    马红; 郭春花; 杨香玖; 鲁华东; 陈立刚; 黄延玲; 张文强

    2014-01-01

    BACKGROUND:Conflicting data have been reported regarding the expression of retinol-binding protein 4 in non-alcoholic fatty liver disease. OBJECTIVE:To evaluate the impact of dietary interventionversus metformin treatment on expression of retinol-binding protein 4 in rats with non-alcoholic fatty liver disease. METHODS: Fifty male Sprague-Dawley rats were randomized to six groups, including two normal control groups (rats were kiled after 8 and 16 weeks of normal diet), two HFD groups (rats were kiled after 8 and 16 weeks of high-fat diet), one dietary intervention group (rats were kiled after 8 weeks of high-fat diet and 8 weeks of normal diet) and one metformin treatment group (rats were kiled after 8 weeks of high-fat diet and 8 weeks of high-fat diet and metformin treatment). The levels of retinol-binding protein 4 in serum and biochemical indexes were detected through enzyme-linked immunosorbent assay. The expression of retinol-binding protein 4 mRNA in liver tissues was measuredvia western blot analysis, immunohistochemistry and RT-PCR. RESULTS AND CONCLUSION:Non-alcoholic fatty liver disease models were successfuly established by high-fat diet. Liver tissues of high-fat diet fed rats showed progressing non-alcoholic fatty liver disease histology, from non-alcoholic fatty liver to non-alcoholic steatohepatitis. Dietary intervention increased retinol-binding protein 4 expression in liver tissue as wel as improving liver enzyme, dyslipidemia and insulin resistance, and aleviated impaired liver histology. Metformin treatment only aleviated hepatic steatosis caused by high-fat diet. The results indicated that retinol-binding protein 4 expression might play a role in the pathogenesis of non-alcoholic fatty liver disease. Metformin treatment can aleviate non-alcoholic fatty liver disease histology,dietary intervention should be the fundamental treatment.%背景:目前关于血清视黄醇结合蛋白4在非酒精性脂肪性肝病中的表达水平仍存在争

  13. 大鼠肝脏组织视黄醇结合蛋白4在衰老过程中表达及与胰岛素抵抗的关系%The increased expression of retinol binding protein 4 during aging in rat liver and the relation to insulin resistance

    Institute of Scientific and Technical Information of China (English)

    王兆君; 张秀锦; 何疆春; 杨晔; 叶平

    2012-01-01

    Objective;To investigate difference expression of retinol binding protein 4( RBP4) during aging in liver tissue of rat and explore the molecular mechanism of insulin resistance(IR). Methods: We used the minimal model technique of Bergman to estimate the insulin sensitivity of young(8 - 12 weeks) and aged (24months) rat. The levels of RBP4 and peroxisome proliferator-activated receptora ( PPARα) mRNA were measured by reverse transcription-polymerse chain reaction ( RT-PCR) and the proteins of RBP4 and PPARα were determined by western blotting,respectively. Results;The degree of IR in the aged group was significantly increased compared with that in the young group. The RBP4mRNA and protein of the aged group were significantly increased. The PPARα mRNA and protein of the aged group were significantly decreased. Conclusion: The mechanism of IR during aging is probably associated with the increased expression of RBP4 in rat liver.%目的:观察大鼠肝脏组织视黄醇结合蛋白4( retinol binding protein4,RBP4)在衰老过程中表达差异,在分子水平上探讨衰老过程中出现胰岛素抵抗(insulin resistance,IR)的可能机制.方法:用Bergman创立的微小模型技术评价年轻鼠(8~12周龄)和老年鼠(24个月龄)的胰岛素敏感性,取大鼠肝脏组织提取总RNA,采用半定量RT-PCR法检测RBP4和过氧化体增殖物激活型受体α(peroxisome proliferator-activated receptorα,PPARα)mRNA水平,用Western blot法检测RBP4和PPARα蛋白表达情况.结果:与年轻鼠组比较,老年鼠组存在明显的胰岛素抵抗,而老年鼠组的RBP4mRNA及蛋白表达明显升高,PPARαmRNA及蛋白表达明显减少.结论:衰老过程中大鼠肝脏组织RBP4表达升高可能与胰岛素抵抗有关.

  14. Influência da resposta inflamatória de fase aguda nos níveis séricos de retinol e da proteína de ligação do retinol em pacientes com AIDS Influence of acute-phase inflammatory response on serum levels of retinol and retinol binding protein in HIV/AIDS patients

    Directory of Open Access Journals (Sweden)

    Fábio Fernandes Neves

    2010-02-01

    Full Text Available INTRODUÇÃO: a hiporretinolemia constitui fator prognóstico independente em pacientes com AIDS, e a atividade inflamatória causa redução dos níveis séricos deste nutriente na população em geral. Entretanto, faltam estudos que avaliem o impacto da atividade inflamatória sobre o nível sérico do retinol em pacientes com AIDS. MÉTODOS: foram avaliados transversalmente 41 pacientes internados por complicações da AIDS, que tiveram quantificados alguns marcadores de inflamação (proteína C reativa e fator de necrose tumoral alfa e concentrações séricas de retinol e da proteína de ligação do retinol. RESULTADOS: apesar da baixa (14,6% prevalência de hiporretinolemia evidenciou-se correlação negativa dos marcadores de inflamação com os níveis séricos de retinol e de sua proteína de ligação nos pacientes com AIDS. CONCLUSÕES: a atividade inflamatória de fase aguda está associada a baixos níveis séricos de retinol em indivíduos com AIDS.INTRODUCTION: Hyporetinolemia is an independent prognostic factor in AIDS patients. Inflammatory activity causes a reduction in the serum levels of this nutrient in the general population. However, there are no studies assessing the impact of inflammatory activity on the serum retinol level in AIDS patients. METHODS: A cross-sectional assessment was conducted on 41 patients hospitalized due to AIDS complications. Inflammatory markers (C-reactive protein and tumor necrosis factor-alpha and serum retinol and retinol binding protein concentrations were quantified. RESULTS: Despite the low (14.6% prevalence of hyporetinolemia, a significant negative correlation was observed between the inflammatory markers and the serum retinol and retinol binding protein levels in AIDS patients. CONCLUSIONS: Acute-phase inflammatory activity is associated with low serum retinol levels in individuals with AIDS.

  15. Relationship between Plasma Retinol-binding Protein 4 and Intima-media Thickness of Common Iliac Artery in Newly Diagnosed Type 2 Diabetics%新诊T2DM患者血浆RBP4与髂动脉内中膜厚度的关系研究

    Institute of Scientific and Technical Information of China (English)

    钟慧; 漆辉洲; 游咏; 陈雯; 冯聚玲; 谢娟; 李熠

    2014-01-01

    Objective To evaluate the relationship between the concentration of plasma retinol-binding protein 4 (RBP4) and intima-media thickness of common iliac artery (CIA-IMT) in newly diagnosed type 2 diabetic (T2DM) patients. Methods There were 180 newly diagnosed T2DM patients in study. Their plasma retinol-binding protein 4 level and other clinic index were tested. The patients were divided into three groups based on the concentrations of RBP4 to compare their CIA-IMT. The relevance of RBP4 and other parameters were analyzed by Pearson correlation analysis. Results CIA-IMT of RBP4 high tertile group was significantly thicker than other groups ( P<0.05). It is showed by Pearson correlation analysis that the concentration of RBP4 in T2DM patients is positively correlated with BMI, FBS, PBS, FINS and HOMA-IR.Conclusion CIA-IMT in newly diagnosed T2DM patients is closely correlated with plasma RBP4 levels.%目的:探讨新诊2型糖尿病(T2DM)患者血浆视黄醇结合蛋白4(RBP4)与髂动脉内中膜厚度(CIA-IMT)的关系。方法180例新诊T2DM患者测定血浆RBP4浓度、血糖、糖化血红蛋白(HbA1c)、血脂、胰岛素(FINS)及CIA-IMT,根据RBP4浓度由低到高按三分位法将180例患者分为三组,比较其CIA-IMT;用Pearson相关分析分析RBP4与其他指标的相关性。结果T2DM患者RBP4上三分位组CIA-IMT比其余两组增厚,差异有统计学意义(P<0.05);Pearson相关分析显示T2DM患者血浆RBP4与BMI、FBS、PBS、FINS及HOMA-IR呈正相关。结论新诊T2DM患者的血浆RBP4水平与CIA-IMT密切相关。

  16. 短期膳食赖氨酸摄入量对健康青年男性血浆PA、RBP水平的影响及意义%Effect of different dietary lysine intakes on the plasma prealbumin and retinol-binding protein levels of healthy male youths in short period

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    田颖; 彭景; 陈玉; 李哲光; 龚君俊; 丰晔; 陈俊

    2012-01-01

    Objective To provide evidence to establish the lysine reference intakes for different population. Methods Seven healthy young men were selected as subjects. Five dietary lysine intakes of 25 , 35 , 45, 55 , 65 mg/( kg · d) were given to subjects from high to low every week by turns. From the 1st day to the 6th day of each experiment week were adaptation days, and the 7 th day was blood sample collection day. Plasma prealbumin and retinol-binding protein levels were detected by ELISA method. Results The actual dietary lysine intakes were 26, 41, 49, 63, 77 mg/( kg · d). There were no significant differences between the five experimental results and the results before the experiment. Conclusion There is no effect of dietary lysine intakes between 26 to 77 mg/ ( kg · d ) on the plasma prealbumin and retinol-binding protein levels of healthy young male subjects in seven days.%目的 为确定健康人群赖氨酸需要量提供理论依据.方法 选取7例健康青年男性作为研究对象,设定25、35、45、55、65mg/(kg·d)5个膳食赖氨酸水平,由高到低依次给予,每周1个剂量,共5周;每周的第1~6天为适应期,第7天采集受试者静脉血,采用ELISA法检测血浆前白蛋白(PA)、视黄醇结合蛋白(RBP)水平.结果 膳食赖氨酸的实际摄入量为26、41、49、63、77 mg/(kg·d),与实验前相比,摄入5个膳食赖氨酸水平者PA、RBP变化无统计学意义.结论 健康青年男性7天膳食赖氨酸摄入量为26 ~77 mg/(kg·d)不会对血浆PA、RBP水平造成影响.

  17. Levels of Retinol-Binding Protein 4 in Neonates Umbilical Blood and Serum of Gestational Diabetes Mellitus Patients and Normal Pregnant Women during Different Gestational Weeks%妊娠期糖尿病患者和正常孕妇在不同孕周中血清及新生儿脐血中视黄醇结合蛋白4的含量变化

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    孙霞; 韩淑娟; 纪向虹; 王茜

    2015-01-01

    Objective:To study the expression of retinol-binding protein 4 in neonates umbilical blood and serum of gestational diabetics and normal pregnant women during different gestational weeks in order to provide basis for the estimation and treatment of gestational diabetes mellitus(GDM).Method:Among the pregnant women who received antenatal care in our hospital from January 2013 to December 2013,50 pregnant women with GDM were selected as the experimental group,50 normal pregnant women were selected as the control group.The retinol-binding protein 4 levels in serum of neonates umbilical cord and pregnancy of 31 to 33 weeks and 37 to 41 weeks were detected through ELISA method.Result:The retinol-binding protein 4 was increased according with the increase of gestational weeks, the differences of it in different times were statistically significant(P<0.001). The retinol-binding protein 4 of the experimental group in different times was higher than that of the control group,the difference was statistically significant (P<0.001).The difference values in retinol-binding protein 4 of the two groups were increased with the time, the differences were statistically significant(P<0.001).The ranges of retinol-binding protein 4 in the experimental group were greater than those in the control group, the differences were statistically significant(P<0.001).The retinol-binding protein 4 of the experimental group had positive correlations with FBG,FINS and HOMA-IR(P<0.001). Conclusion:Retinol-binding protein 4 levels may use as the basis for the prediction and assessment of GDM and as the guidelines for the treatment of gestational diabetes mellitus.%目的:研究视黄醇结合蛋白4在妊娠期糖尿病患者和正常孕妇的不同孕周的血清及新生儿脐血中的表达,为妊娠期糖尿病的预测及治疗提供依据。方法:选择2013年1-12月在本院产科产检的妊娠期糖尿病孕妇50例作为试验组,正常孕妇50例作

  18. Relationship between serum retinol binding protein 4 and the heart rate variability in hypertension patients with acute cerebral infarction%高血压病合并急性脑梗死患者血清视黄醇结合蛋白4与心率变异性的关系

    Institute of Scientific and Technical Information of China (English)

    刘涛生; 张爱军; 周志鸿; 郑凤霞

    2012-01-01

    Objective To investigate the relationship between serum retinol binding protein 4 ( RBP4 ) and heart rate variability HRV )in hypertension patients with acute cerebral infarction. Methods 78 cases of hypertension patients with a-cute cerebral infarction were enrolled in the observation group, 50 cases of simple hypertension patients were enrolled in the control group. Enzyme linked immunosorbent assay of serum RBP4 levels of the subjects were measured, ambulatory blood pressure were used to monitor heart rate variability time domain parameters, included SDNN, SDANN, SDNN index, rMSSD and PNN50. Results The serum retinol binding protein 4 levels in control group and observation group were( 15. 5 ± 5.4 )mg/ L and( 24. 2 ±7. 6 )mg/L respectively, the difference between them was statistically significant( P <0. 01 ). The time domain HRV parameters in control group and observation group were as follows, SDNN ( 112. 3 ±21. 9 vs. 79. 7 ± 19. 1 )ms, SDANN (36.1 ±9.3 vs. 25. 8±7.2)ms,SDNN index(96.7±26. 8 vs. 81.3 ±25.0 )ms,rMSSD ( 23.2 ±7.9 vs. 19.4 ±5.7 )ms, PNN50 ( 8. 9 ±4. 1 vs. 5. 7 ±3. 2 )% ,these data in the observation group were lwoer than in the control group,the differences were statistically significant P <0.05 ). Pearson linear correlation analysis showed that serum RBP4 and SDNN( r = - 0. 483, P <0.01 ), SDANN( r = -0.452, P <0.01 ), SDNN index( r = -0.414, P <0.01 ),rMSSD( r = -0.293, P < 0. 05 ), PNN50( r = -0.286, P <0. 05 ) were negative correlated. Conclusion The serum retinol binding protein 4 was negative correlated with heart rate variability parameters. Serum retinol binding protein 4 might be part of autonomic imbalance in hypertension patients with acute cerebral infarction.%目的 探讨高血压病合并急性脑梗死患者血清视黄醇结合蛋白4(RBP4)与心率变异性(HRV)之间的关系.方法 选择78例高血压病合并急性脑梗死患者为观察组,以50例单纯高血压病为对照组.采用酶联免疫吸

  19. Effect of antihypertensive drugs on plasma adiponection and retinol binding protein 4 in elderly patients with essential hypertension%降压药物对老年高血压患者血浆脂联素和视黄醛结合蛋白4含量的影响

    Institute of Scientific and Technical Information of China (English)

    曹萍; 沈丹; 钟亚; 李睿

    2013-01-01

    目的 观察老年高血压患者应用氨氯地平、培哚普利、缬沙坦3种药物降压治疗前后的血浆脂联素和血浆视黄醛结合蛋白含量的变化. 方法 选择2007年3月至2010年7月年在我院住院的老年高血压患者238例,完成研究1 93例,数字抽签随机分为3组,分别用氨氯地平、培哚普利、缬沙坦治疗,1 2周后观察血压、心率、身高、体质量、腹围、腰围、血脂、血浆脂联素及视黄醛结合蛋白水平等改变. 结果 氨氯地平组、培哚普利组、缬沙坦组治疗后血压均较治疗前下降(均P<0.01);治疗后3组血压比较,差异无统计学意义(均P>0.05).治疗前、后血浆脂联素水平培哚普利组(7.4±1.8)μg/L与(8.3±1.8)μg/L、缬沙坦组(7.5±1.7)μg/L与(8.4±1.9)μg/L较治疗前升高(均P<0.01);治疗后培哚普利组、缬沙坦组血浆脂联素水平高于氨氯地平组(7.6±1.8)μg/L(均P<0.05).治疗后培哚普利组、缬沙坦组血浆视黄醛结合蛋白水平较治疗前降低(P<0.01).氨氯地平组较治疗前血浆视黄醛结合蛋白水平降低,但差异无统计学意义(P>0.05).血浆视黄醛结合蛋白水平治疗后培哚普利组(36.6±14.2) mg/L、缬沙坦组(36.3±14.1)mg/L低于氨氯地平组(42.7±13.8)mg/L,差异有统计学意义(均P<0.01). 结论 培哚普利、缬沙坦能提高老年高血压病患者血浆脂联素水平,降低血浆视黄醛结合蛋白水平,从而起到降压作用以外的心血管保护作用.%Objective To explore the effects of amlodipine,perindopril and valsartan on plasma adiponectin and retinol binding protein 4 in elderly patients with essential hypertension.Methods From March 2007 to July 2010,238 elderly patients with essential hypertension were selected and 193 cases completed this study.Patients were randomly divided into 3 groups:amlodipine group (n=68),perindoprilgroup (n=60) and valsartan group (n=65).Patients in each group were treated with amlodipine

  20. Effects of retinol binding protein 4 knockdown on the PI3K/Akt pathways in porcine adipocytes%干扰视黄醇结合蛋白4对猪脂肪细胞PI3K/Akt信号通路的影响

    Institute of Scientific and Technical Information of China (English)

    蒲蕾; 程佳; 吴国芳; 杨浩; 仇杨; 张振宇; 杨公社; 孙世铎

    2013-01-01

    视黄醇结合蛋白4 (Retinol binding protein 4,RBP4)是一种脂肪细胞分泌因子,其表达水平的升高与胰岛素抵抗及Ⅱ型糖尿病等疾病密切相关,但具体作用机制尚不清楚.为明确此机制,通过包装RBP4干扰慢病毒并侵染猪前体脂肪细胞.运用胰岛素激活及诱导胰岛素抵抗模型,利用QRT-PCR及Western blotting方法检测RBP4的干扰效率及处理组PI3K/Akt信号通路相关基因的表达.结果显示RBP4的基因及蛋白的干扰效率达到60%(P<0.01)以上.进一步研究发现在胰岛素诱导及胰岛素抵抗的情况下,LH1-shRBP4干扰后可显著提高胰岛素信号通路AKT2、PI3K.GLUT4和IRS1基因mRNA的表达;明显促进AKT2、PI3K和IRS1蛋白的磷酸化;提高AKT2、PI3K和GLUT4基因的总蛋白水平.总之,RBP4干扰通过上调PI3K/Akt胰岛素信号通路相关因子的表达及其磷酸化水平,提高了胰岛素敏感性.此研究将为胰岛素抵抗相关疾病的治疗提供新思路.%Retinol-binding protein 4 (RBP4) is adipocyte-derived secreted adipokines and elevated RBP4 expression level was closely related to insulin resistance and type Ⅱ diabetes mellitus. However, the exact mechanisms are unknown. To clarify the mechanism, RBP4 lentivirus particles were packaged to infect porcine preadipocytes. Then porcine preadipocytes were activated by insulin or induced model of insulin resistance. RBP4 interference efficiency and the gene expression of each treatment groups in PBK/Akt pathways were examined by QRT-PCR and Western blotting. The result shows that RBP4 mRNA and protein expressions were suppressed more than 60% (P<0.01). Furthermore, no matter under insulin stimulation or insulin resistance, RBP4 knockdown significantly increased the mRNA expressions of AKT2, PI3K, GLUT4 and IRS1 compared with the control. The protein phosphorylate levels of AKT2, PI3K, IRS1 arised, meanwhile enhanced the AKT2, PI3K, GLUT4 total protein expressions. Collectively

  1. Association of serum lipoprotein (a) level,retinol-binding protein 4 with diabetic retinopathy in type 2 diabetes%血清脂蛋白(a)和视黄醇结合蛋白4与2型糖尿病视网膜病变的相关性

    Institute of Scientific and Technical Information of China (English)

    田婷; 马向华; 沈捷

    2011-01-01

    Objective; To investigate the independent risk factors related to the development of diabetic retinopathy (DR) for type 2 diabetic patients. Methods; A case-control study containing 82 DR patients and 86 diabetics patients without DR (NDR) was per-formed from January,2009 to December,2010. The clinical parameter and biochemical indicators were compared between the two groups. Conditional Logistic regression analysis was further performed to assess variables independently associated with the DR de-veloping. Results; In the univariate analysis,duration of diabetes,HbA1c,diastolic blood pressure and retinol-binding protein 4 (RBP4) were significant between DR and NDR. Logistic regression analysis showed that duration of diabetes(OR=2.41 ;95%CI; 1.12-5.18),lipoprotein (a) (OR=2.22;95% CI: 1.15~4.31) and RBP4 (OR=2.95;95% CI:1.54~5.65) were significant and independent predictors of the DR developing. Conclusion; These data suggest that duration of diabetes,lipoprotein(a) and RBP4 level are inde-pendent risk factors for the development of DR in type 2 diabetics.%目的:探讨2型糖尿病视网膜病变发生的独立危险因素.方法:选取南京医科大学第一附属医院内分泌科2009年1月~2010年12月82例糖尿病视网膜病变患者和86例不伴有视网膜病变的2型糖尿病患者进行病例-对照研究.比较两组临床参数及生化指标,对于有意义的指标进一步行Logistic回归分析,寻找糖尿病视网膜病变的独立预后指标.结果:单变量分析结果显示,两组间糖尿病病程、糖化血红蛋白、舒张压及视黄醇结合蛋白4(retinol-binding protein 4,RBP4)有统计学差异.Logistic回归分析显示:糖尿病病程(OR=2.41;95% CI:1.12~5.18)、脂蛋白(a) (OR=2.22;95% CI:1.15~4.31)和RBP4 (OR=2.95;95% CI:1.54~5.65)是糖尿病视网膜病变发生的独立预测指标.结论:脂蛋白(a)和RBP4是糖尿病视网膜病变发生的危险因素,且为独立的预测因子.

  2. Effects of telmisartan on insulin resistance and serum retinol-binding protein 4 in patients with essential hypertension%替米沙坦对肥胖高血压患者胰岛素抵抗和血清视黄醇结合蛋白4水平的影响

    Institute of Scientific and Technical Information of China (English)

    黄高忠; 张蓓; 胡挺军; 张莉; 王蓓芸; 章晓燕; 钟远

    2011-01-01

    AIM: To investigate the effects of telmisartan on insulin resistance and serum retinol-binding protein 4 in patients with essential hypertension. METHODS: Forty-five subjects with essential hypertension were treated with telmisartan (80 mg/day) or losartan (100 mg/day) combined with long-acting calcium antagonist, if necessary, for 16 weeks. Waist and hip circumference, body mass index, blood pressure, fasting plasma glucose (FPG), insulin (FPI), lipid and retinol-binding protein 4 (RBP4)were measured before and after the treatment. Insulin sensitivity was estimated by homeostasis model assessment (HOMA-IR). RESULTS: Compared with baseline levels, systolic and diastolic blood pressure decreased significantly in both groups. But the levels of HOMA-IR and RBP4 decreased significantly only in telmisartan group. CONCLUSION: Telmisartan improves insulin resistance and decreases serum RBP4 level in patients with essential hypertension.%目的:观察替米沙坦对伴超重或肥胖的高血压患者血压、精脂代谢指标和血清视黄醇结合蛋白4(RBP4)水平的影响.方法:将45例门诊超重或肥胖的原发性高血压患者随机分为替米沙坦组(n=23)和氯沙坦组(n=22),分别给予替米沙坦80 mg(qd)或氯沙坦100 mg(qd),必要时加用长效钙拮抗剂,治疗16周.观察用药前后腰围、腰臀比、体质量指数、血压、空腹血糖、胰岛素、血脂和血清RBP4含量的变化.采用稳态模式法计算胰岛素抵抗指数(HOMA-IR).结果:两组治疗后,收缩压及舒张压与治疗前比较均明显下降,替米沙坦组分别降低20.5 mmHg和14.8mmHg,氧沙坦组分别降低18.3 mmH和14.2 mmHg,下降幅度组间比较无差异;替米沙坦组HOMA-IR和血清RBP4的含量明显下降,分别由7.24±1.82下降至6.02±2.16(P<0.05)和(46.9±15.0)mg/L下降至(39.8±14.8)mg/L(P<0.05).结论:替米沙坦可改善肥胖伴高血压患者的胰岛素敏感性、降低血清RBP4的水平.

  3. 飞行员血液视黄醇结合蛋白4与冠心病危险因素的相关性%Research on correlation between blood retinol binding protein4 and coronary heart disease risk factors in pilots

    Institute of Scientific and Technical Information of China (English)

    刘芳芳; 罗惠兰; 蒋晓旋; 那美晶; 代传芬

    2015-01-01

    目的:研究飞行员血液视黄醇结合蛋白4(retinol binding protein 4,RBP4)水平变化及其与冠心病危险因素的相关性。方法选取军事飞行员477例,冠心病患者44例,普通地面工作健康体检者202例,采用酶联免疫吸附法测定受试者RBP4水平,测量身高、体重、血压等,并采集记录相应生化数据:总胆固醇(TC)、三酰甘油(TG)、空腹血糖(FBG)、尿酸(UA),应用统计软件进行统计检验。结果冠心病组血液RBP4水平明显高于普通健康人群组(t=5.986,P<0.01);飞行员组血液RBP4水平明显高于普通健康人群组(t=4.822,P<0.01)。在相同年龄组中,飞行员组血液RBP4水平均高于普通健康人群组(t=2.091、3.048、3.424,P<0.05),但飞行员各年龄组间血液RBP4水平差异无统计学意义;飞行员组不同飞行时间组间血液RBP4水平差异无统计学意义。结论飞行因素可能导致飞行员血液RBP4水平升高,而RBP4水平升高可能是飞行员冠心病的危险因素。%ObjectiveTo study the change of blood retinol binding protein 4(RBP4) concentration in pilots and investigate the correlation between RBP4 and coronary heart disease(CHD) risk factors for the pilots.MethodsSerum sample were taken from 477 military pilots,44 patients with coronary heart disease and 202 healthy ground service personnel. The serum level of RBP4 was measured by enzyme linked immune sorbent assay(ELISA), the body height, weight, blood Pressure were measured, and the appropriate biochemical data: total cholesterol (TC), triglyceride (TG), fasting blood glucose (FBG), uric acid (UA) were collected and recorded, and statistical software was adopted for the statistical testing.ResultsThe serum level of RBP4 in CHD was significantly higher thannormal healthy population group (t=5.986,P<0.01); the serum level of RBP4 in pilot was significantly higher than normal healthy population group (t=4

  4. SIGNIFICANCE OF URINARY RETINOL BINDING PROTEIN IN DIAGNOSIS OF EARLY RENAL TUBULAR INJURY%尿视黄醇结合蛋白检测在糖尿病早期肾小管损伤诊断中的意义

    Institute of Scientific and Technical Information of China (English)

    樊淑珍; 刘云彪; 张彩虹

    2012-01-01

    Objective:To determine the content of Urinary Retinol Binding Protein( RBP)in urine and further,and explore the effects and significance of RBP in the diagnosis of early renal tubular injury in patients with hypertention and diabetes. Methods; 106 patients with diabetes and hypertention were divided into 6 groups,which were the group of the patients with single hypertention,hypertention complicated with kidney diseases, diabetes without kidney diseases, diabetes complicated with kidney diseases, diabetes complicated with hypertension and the patients complicated with diabetes, hypertention and kidney diseases. Meanwhile,55 healthy patients were setted as normal control group. OLYMPUS AU2700 fully automatic biochemistry analyzer was used to assay RBP in each group. Results: The RBP Value was 0.45 ±0. 16 in normal group,the RBP value were between 0. 57 ±0. 18 and 17. 22 ± 3. 11 in experience group, which implies the RBP in the hypertention patients complicated with diabetes is significantly different from group. Conclusions: Assay of RBP is important to make a diagnosis of early renal tubular injury in patients with hypertention and diabetes, which can be termed as a reference index in diagnosing early renal tubular injury in patients with hypertention and diabetes.%目的:检测尿液中视黄醇结合蛋白( Retinol - binding protein,RBP)含量水平,探讨尿液中RBP在高血压、糖尿病早期肾小管损伤中的作用及意义.方法:选取106例糖尿病及高血压病人,分为高血压无肾病组、高血压合并肾病组、糖尿病无肾病组、糖尿病合并肾病组、糖尿病高血压无肾病组和糖尿病高血压合并肾病组等6个组,同时选择55例正常体检病人做对照组.采用OLYMPUS AU2700全自动生化分析仪对各组尿液RBP进行检测,并经统计学分析处理.结果:正常对照组尿液RBP值0.45±0.16;实验组尿液RBP在0.57±0.18~17.22±3.11之间.即高血压和糖尿病病人尿液

  5. 急性心肌梗死患者血清视黄醇结合蛋白4的变化及意义%Changes of serum retinol binding proteins 4 (RBP4) of acute myocardial infarction patients and its significance

    Institute of Scientific and Technical Information of China (English)

    王治中

    2012-01-01

    OBJECTIVE To observe the changes of serum retinol binding proteins 4 (RBP4) of acute myocardial infarction patients , and to discuss the significance of detecting serum RBP4 in acute myocardial infarction. METHODS 59 patients with a-cute myocardial infarction (AMI) and coronary intervention after surgery, 31 cases of patients without AMI, 40 patients in control group, all used enzyme-linked immunosorbent adsorption method (ELISA) to determinate RBP4 serum level. RESULTS Serum RBP4 in patients with acute myocardial infarction was higher than other group (P < 0.01), serum RBP4 level before and after coronary intervention surgery was obviously different (P< 0.01). CONCLUSION RBP4 could be as early diagnosis and clinical observation index for acute myocardial infarction.%目的 观察急性心肌梗死患者血清视黄醇结合蛋白4 (RBP4)的变化,探讨检测血清RBP4在急性心肌梗死中的意义.方法 59例急性心肌梗死(AMI)患者及冠脉介入手术后,31例非AMI患者,40例对照组,均采用酶联免疫吸附法(ELISA)测定血清RBP4水平.结果 急性心肌梗死患者血清RBP4高于其他对照组(P<0.01),冠脉介入手术前后血清RBP4水平有明显变化(P<0.01).结论 RBP4可作为急性心肌梗死早期诊断和疗效观察指标.

  6. The correlation between retinol binding protein 4 and nonalcoholic fatty liver disease in newly-diagnosed type 2 diabetes mellitus%视黄醇结合蛋白4与新诊断2型糖尿病合并非酒精性脂肪肝的关系研究

    Institute of Scientific and Technical Information of China (English)

    桑谊荃; 马向华; 倪娟; 谢媛; 李晓娜; 俞岭

    2013-01-01

    Objective:To investigate the metabolic characteristics of newly-diagnosed type 2 diabetes with nonalcoholic fatty liver disease (NAFLD) and the correlation between retinol binding protein 4 in newly-diagnosed type 2 diabetes with nonalcoholic fatty liver disease.Methods:A total of 216 patients with newly-diagnosed type 2 diabetes were enrolled in this study.They were divided into two groups according to with or without NAFLD.We compared the blood pressure,body mass index (BMI),blood lipids [TC,TG,HDL,LDL,Lp (a)],fasting glucose,fasting insulin,HbA1c,uric acid,liver function and retinol binding protein 4(RBP4).Logistic regression and Pearson correlation were performed to analyze the related factors.Results:The levels of BMI,systolic blood pressure,diastolic blood pressure were much higher in T2DM with NAFLD group than T2DM without NAFLD group.After adjustment of age,sex and BMI,the levels of triglyceride,total cholesterol,fasting insulin,insulin resistance index (HOMA-IR),ALT,γ-GGT,uric acid,RBP4 were significant higher in newly-diagnosed type 2 diabetes with NAFLD disease (P < 0.05).In logistic regression analysis,BMI,ALT and RBP4 were significant and independent predictors of newly-diagnosed type 2 diabetes with NAFLD (P < 0.05).RBP4 was significantly correlated with HOMA-IR,HbA 1 c,FINS,γ-GGT,UA (P < 0.05).Conclusion:The results suggest that newly-diagnosed type 2 diabetes with NAFLD displayed with the components of metabolic syndrome RBP4 may be an important indicator of nonalcoholic fatty liver disease in newly-diagnosed type 2 diabetes.%目的:探讨新诊断的2型糖尿病(type 2 diabetes mellitus,T2DM)合并非酒精性脂肪肝(nonalcoholic fatty liver disease,NAFLD)的代谢特征及与视黄醇结合蛋白4(retinol binding protein 4,RBP4)的关系.方法:收集新诊断的T2DM住院患者216例,根据是否合并NAFLD分为T2DM伴有NAFLD组144例和T2DM不伴NAFLD组72例.测量两组患者血压、体质指数(body mass index

  7. Investigation of urine β2-microglobulin, retinol binding protein and mAlb determination in the diagnosis of chronic cadmium poisoning%尿液β2-微球蛋白、视黄醇结合蛋白和微量白蛋白测定对慢性镉中毒诊断价值的探讨

    Institute of Scientific and Technical Information of China (English)

    周妮; 伍细言; 彭艳华; 易海燕

    2013-01-01

    OBJECTIVE To explore the changes and the clinical significance of its value of urine p2-microglobulin ((β2-mi-croglobulin, β2-MG) , retinol binding protein (retinol binding protein, RBP) and mAlb (Microalbuminuria, mAlb) in the diagnosis of chronic cadmium poisoning. METHODS Urinary β2-MG, RBP and mAlb were detected in 86 inpatients whose twice cadmium exceeded (cadmium > 5μg/g.Cr) and normal medical groups (102 people) by latex enhanced immunoturbidi-metric assay, which was adjusted with urine creatinine, then the results of two populations were compared. RESULTS β2-MG, RBP and mAlb by creatinine correction had different levels increasing in the group with urinary cadmium exceeding compared with the normal population. In urinary β2-MG (β2-MG > 1 000.0μg/g.cr) , RBP (RBP > 1 000.0μg/g.cr) , mAlb (mAlb > 30.0mg/g.cr), the positive rates of β2-MG, RBP, mAlb were 40.7%, 37.2%, 46.5%; Positive rates of β2-MG + RBP, β2-MG + mAlb, RBP + mAlb were 51.2%, 58.2%, 54.7%, which was combination with at least one of positive; The positive rate of three combined (β2-MG + RBP + mAlb) was 59.3%, the positive rates of latter three combinations was greater than only urinary β2-MG or RBP and urinary cadmium exceeded twice as the standard diagnosis of chronic cadmium poisoning in GBZ17-2002 "occupational cadmium poisoning diagnostic criteria" . CONCLUSION The urinary β2-MG, RBP, and mAlb of early kidney damage indicators increase in varying degrees in occupational cadmium exceeded the population, and joint detection in combination with clinical symptoms contribute to overall diagnosis of chronic cadmium poisoning patients in cadmium exceeded population.%目的 探讨尿β2-微球蛋白(β2-microglobulin,β2-MG)、视黄醇结合蛋白(retinol binding protein,RBP)和微量白蛋白(Microalbuminuria,mAlb)的改变在慢性镉中毒诊断中的临床意义及其价值.方法 分别应用胶乳增强免疫比浊法、免疫透射比浊法、免疫速率比浊法对某

  8. The clinical application of cystatin C, retinol binding protein and D-dimer in preeclampsia diagnosis%子痫前期患者胱抑素C、视黄醇结合蛋白、D-二聚体检测的临床应用研究

    Institute of Scientific and Technical Information of China (English)

    王艳春; 雒雪

    2016-01-01

    目的:探讨胱抑素C(cystatin C, CysC)、视黄醇结合蛋白(retinol binding protein, RBP)、D-二聚体(D-dimer, D-D)在子痫前期患者诊断中的临床应用价值。方法选取我院220例晚期妊娠住院的子痫前期患者为研究对象,分为轻度子痫前期组120例,重度子痫前期组100例,选择同期正常孕妇100例为对照组,检测所有受试者CysC、RBP及D-D的水平,对检测结果进行统计学分析。结果轻度子痫前期组、重度子痫前期组及对照组间CysC、RBP及D-D差异均有统计学意义(P均<0.05);轻度子痫前期组、重度子痫前期组CysC、RBP及D-D检测结果均高于对照组,且差异均具有统计学意义(P均<0.05);轻度子痫前期组CysC、RBP及D-D的检测结果均高于对照组,且差异均有统计学意义(P均<0.05)。结论 CysC、RBP及D-D在子痫前期病情严重程度评估方面有重要的临床参考意义。%Objective To study the clinical application value of cystatin C (CysC), retinol binding protein(RBP) and D-dimer(D-D) in preeclampsia diagnosis. Methods 220 cases patients with preeclamp-sia in our hospital from May 2015 to February 2016 were collected , and were divided into mild preeclampsia group(120 cases), severe preeclampsia group(100 cases). 100 cases normal pregnant women at the same pe-riod were collected as control group. The CysC, RBP and D-D levels of all the subjects were all detected, and the results were analyzed statistically. Results There were statistical significance in the differences of serum CysC, RBP and D-D levels among mild preeclampsia group, severe preeclampsia group and control group (Pall<0.05). The CysC, RBP and D-D levels in mild preeclampsia group and severe preeclampsia group were all higher than that of control group, and the differences all had statistical significance(Pall<0.05). The CysC, RBP and D-D levels in severe preeclampsia group were all

  9. 尿液视黄醇结合蛋白-4水平变化在慢性心力衰竭患者中的临床价值%The Changes and Clinical Significance of Urinary Retinol-binding Protein-4 Protein Level in Patients with Chronic Heart Failure

    Institute of Scientific and Technical Information of China (English)

    戴海浪

    2013-01-01

    目的探讨尿液蛋白视黄醇结合蛋白-4(RBP-4)在临床应用中的价值。方法运用酶联免疫吸附法对60例正常对照组和108例慢性心力衰竭患者的尿液样本进行RBP-4蛋白浓度检测,结合临床资料进行统计分析。结果尿液RBP-4蛋白在慢性心力衰竭患者中含量显著高于正常对照组(1.66±0.82 mg/ml vs.0.28±0.11 mg/ml,P<0.0001),且其含量在慢性心力衰竭患者合并有肾功能损害时显著升高,差异有显著性意义(P=0.0015)。结论检测尿液视黄醇结合蛋白-4(RBP-4)的水平对于诊断和监测慢性心力衰竭进展有一定应用价值。%Objective To study the significance of urinary Retinol-binding protein-4 (RBP-4) in the urine form patients with chronic heart failure (CHF). Methods We applied enzyme-linked immunosorbent assay (ELISA) to measure the expression level of RBP-4 in the urine from 60 normal controls and 108 patients with CHF validation, then the statistical analysis was done with the ELISA results coupled with clinical data. Results The level of RBP-4 was significantly elevated in urine form CHF patients versus normal controls (1.66±0.82 mg/ml vs. 0.28±0.11 mg/ml,P <0.0001). Moreover, RBP-4 was markedly increased in CHF patients with impaired renal function than normal renal function(P=0.0015.)Conclusion The urinary RBP-4 level may have an important value in detection and surveil ance of chronic heart failure.

  10. The Correlation Research between Retinol Binding Protein 4 and Inflammatory Cytokines of Patients with Coronary Heart Disease%冠心病患者炎性因子的变化及其与血清视黄醇结合蛋白4水平的相关性研究

    Institute of Scientific and Technical Information of China (English)

    吴桂平; 付鑫; 张彦红; 邹慕蔚; 万多

    2014-01-01

    Objective To discuss the relationship between the high sensitivity C-reactive protein(hs-CRP),interleukin-6,monocyte chemoattractant protein-1 and Retinol binding protein 4 of patients with coronary heart disease. Methods The healthy group, AS group and CHD group were collected. The serum level of RBP4, hs-CRP, IL-6, MCP-1 was measured.Results Compared with the healthy group, The serum level of RBP4 and hs-CRP, IL-6. MCP-1 were higher in AS and CHD group that in healthy group (P<0.05 or P<0.01).Correlation analysis showed that The serum level of RBP4 and hs-CRP,IL-6.MCP-1 were signiifeantly positive correlation in AS and CHD group. Conclusion RBP4 involve the Inlfammatory reaction process of Atherosclerosis, which could partake the the occurrence of coronary heart disease development through many ways directly or indirectly.%目的:探讨冠心病患者血清高敏C反应蛋白(hs-CRP)、白细胞介素-6(IL-6)、MCP-1与视黄醇结合蛋白4(RBP4)的相关性。方法分别收集健康组、动脉粥样硬化组、CHD组患者,检测其空腹血清RBP4、hs-CRP、IL-6、MCP-1水平。结果与健康组相比,AS组、CHD组患者血清RBP4、hs-CRP、IL-6、MCP-1含量明显升高(P<0.05或P<0.01);相关性分析显示AS组、CHD组患者血清RBP4与炎性因子hs-CRP、IL-6、MCP-1呈正相关。结论 RBP4参与了动脉粥样硬化的炎性反应过程,其可能通过多种途径直接或间接地参与冠心病的发生发展。

  11. 视黄醇结合蛋白RBP4可与多种核受体相互作用%Retinol Binding Protein Could Interacts with Many Nuclear Receptors

    Institute of Scientific and Technical Information of China (English)

    陈健; 陈敏; 陈彬; 李渝萍; 李强; 周度金

    2004-01-01

    In order to explore the tunctions ot retinol bining protein (RBP4)in regulation of gene expression, yeast two hybrid assay and transient co-transforming were used to detect the interactions between RBP4 and nuclear receptors and the effects of over-expressed RBP4 on trans-activation functions of human estrogen receptor related receptor 1 (hERR1) and human estrogen (hER). The requirement of activation function domain-2 (AF-2) for hER to interact with RBP4 was also detected by the yeast two hybrid assay. The results show that RBP4 could interact with many nuclear receptors including mouse estrogen receptor related receptor 3 (mERR3), retinoid X receptor (RXR), glucocorticoid receptor (GR), progestin receptor (PR),and androgen receptor (AR) in yeast cells. Over-expressed RBP4 could strongly enhance the trans-activation functions of hERR1 and hER in a dose-dependent manner, respectively. RBP4 could also interact with hER in an AF-2-dependent manner.

  12. Significance of combined determination of serum retinol-binding protein,cystatin C and urine mi-cro-albumin for early diagnosis of diabetic nephropathy%血清视黄醇结合蛋白和胱抑素 C 及尿微量蛋白联合检测对糖尿病肾病早期诊断的意义

    Institute of Scientific and Technical Information of China (English)

    杨芳; 郭春霞

    2016-01-01

    目的:探讨血清视黄醇结合蛋白(RBP)、血清胱抑素 C(Cys C)和尿微量白蛋白(Um ALB)联合检测在糖尿病早期诊断中的意义。方法采用透射比浊法测定血清 RBP 和 Cys C,免疫比浊法检测 Um ALB,并与健康对照组进行比较。结果糖尿病(DM)组与健康对照组比较,血清 RBP、Cys C 和 Um ALB 的含量差异未见统计学意义(P >0.05);糖尿病肾病1组与健康对照组比较差异有统计学意义(P <0.05);糖尿病肾病2组与糖尿病肾病1组比较,血清 RBP、Cys C 和 Um ALB 差异均有统计学意义(P <0.01)。结论联合检测血 RBP、Cys C 和 Um ALB对 DN 的早期诊断有重要意义。%Objective To investigate the significance of combined determination of serum reti-nol-binding protein,cystatin C and urine micro-albumin for early diagnosis of diabetic nephropathy. Methods Quantitative determination of serum retinol-binding protein and cystatin C applied transmission turbidimetry and of urine micro-albumin through immunity turbidimetry,the results were compared with normal control group. Results The contents of serum RBP,Cys C,Um ALB in DM group were similiar with the normal control group(P > 0. 05),but the difference was significant in DN1 group compared with normal group(P <0. 05). The contents of serum RBP,Cys C,Um ALB in DN2 group had significant differ-ence compared with DN1 group(P < 0. 01). Conclusions It is important for early diagnostic in diabetic nephropathy using combined determinations of serum RBP,Cys C and Um ALB.

  13. Serum level of retinol binding protein 4 and related factors in human subjects with impaired glucose regulation and type 2 diabetes%糖尿病患者和糖耐量异常个体血清视黄醇结合蛋白4水平及影响因素的研究

    Institute of Scientific and Technical Information of China (English)

    刘静婧; 任伟; 李素芳; 吴丹东; 李金超; 郑晓雅

    2010-01-01

    目的:探讨初发2型糖尿病(Type 2 diabetes,T2DM)和葡萄糖耐量异常(Impaired glncose regulation,IGR)人群血清视黄醇结合蛋白4(Retinol binding protein 4,RBP4)水平及其影响因素.方法:采用酶联免疫吸附(Enzyme-linked immunosorbent assay,ELISA)法测定27例初发2型糖尿病(T2DM组)、27例糖耐量异常(IGR组)个体的空腹血清RBP4浓度,并用26例糖耐量正常个体(Normal glucose tolerance,NGT)做对照,同时测定血糖、血脂、血压、身高、体重、腰腹围和胰岛素水平,分析各指标与血清RBP4的相关性.结果:初发T2DM和IGR人群血清RBP4水平明显高于正常人群,但是两组人群之间RBP4水平没有差异.多元相关与回归分析显示空腹胰岛素(Fasting insulin,FINS)、胰岛素抵抗(Insulin resistance,IR)和收缩压(Systolic blood pressure,SBP)与RBP4呈正相关,但没有指标是影响血清RBP4水平的主要因素.结论:初发T2DM和IGR人群外周血RBP4蛋白高表达,并与T2DM及其相关临床指标相关,这提示了RBP4可能在T2DM发生发展中起作用.

  14. Detection and clinical significance of retinol binding protein in patients with chronic hepatitis B combined with acute hepatitis E%慢性乙型肝炎重叠急性戊型肝炎患者视黄醇结合蛋白检测

    Institute of Scientific and Technical Information of China (English)

    殷艳天; 王立蓉; 黄菁; 谢劲松

    2013-01-01

    目的 探讨慢性乙型肝炎(慢乙肝)重叠急性戊型肝炎(戊肝)患者视黄醇结合蛋白(RBP)水平变化及临床意义.方法 慢乙肝患者81例分为单纯乙肝(A组,41例)和重叠戊肝(B组,40例)两组,同时随机选择同期健康体检者42例为对照(C组),比较各组RBP水平.结果 A、B组的RBP水平在发作期和恢复期均明显低于C组(P<0.05或P<0.01),B组的RBP水平在发作期和恢复期均明显低于A组(P<0.05或P<0.01).各组RBP与前白蛋白(PA)和白蛋白呈正相关,与ALT和AST呈负相关(P<0.01).结论 RBP水平可以作为慢乙肝患者,尤其在重叠感染时,肝损伤的评估指标.%Objective To study the detection and clinical significance of retinol binding protein (RBP) in the patients with chronic hepatitis B (CHB)combined with acute hepatitis E.Methods Serum levels of RBP were detected in 41 patients with CHB (group A),40 patients with CHB combined with acute hepatitis E(group B) and 42 healthy people(group C).Results Serum levels of RBP in the period of attack and recovery were lower in groups of A and B than those in group C (P<0.05 or P<0.01),which were lower in group B than those in group A(P<0.05 or P<0.01).Serum level of RBP was positively correlated to that of prealbumin(PA) and albumin,but negatively correlated to ALT and AST(P<0.01).Conclusion Serum RBP may be taken as an indicator for evaluating liver damage in the patients with CHB,especially combined with acute hepatitis E.

  15. 急慢性肾衰的指甲肌酐测定与尿视黄醇结合蛋白检测的比较%THE VALUE OF COMPARING MENSTRUATING NAIL CREATININE AND URINE RETINOL-BINDING PROTEIN IN CHRONIC RENAL FAILURE AND ACUTE RENAL FAILURE.

    Institute of Scientific and Technical Information of China (English)

    符克英; 钟路; 占锋

    2001-01-01

    目的:探讨指甲肌酐在鉴别急慢性肾衰的临床意义。方法 指甲肌酐(NCr)应用碱性苦味酸法,尿视黄醇结合蛋白(RBP)应用ELISA法及其与尿肌酐比值。结果 慢性肾衰组(NCr)及健康对照组(NCr)及急性肾衰组(NCr)比较有显著差异(P<0.01)健康对照组(NCr)及急性肾衰组(NCr)比较无显著差异(P>0.05),慢性肾衰组(RBP,RBP/Cr)及急性肾衰组(RBP,RBP/Cr)与健康对照组(RBP,RBP/Cr)比较有显著差异(P<0.01),慢性肾衰组(RBP,RBP/Cr)与急性肾衰组(RBP,RBP/Cr)比较无显著差异(P>0.05)。结论 指甲肌酐含量的测定在鉴别急慢性肾衰中有着重要的临床价值。%Objective:To discuss the clinic significance about nailcreatinine in pa tients of acute renal failure and chronic renal failure.Methods: To use the alkal escent picrate methodology menstruates the nail creatinine(NCr),and to use the E LISA methodology menstruates the retinol-binding protein(RBP),and to use routine methodology menstruates the proportionality between RBP and urine creatinine(RB P/Ucr).Results:In creatinine(NCr),there is a remarkable signific ance between chr onic renal failure group and normal control group ,acute renal failure group(P< 0.01),there is no significance between normal control group and acute renal fail ure(P>0.05),but in RBP,RBP/Ucr,there is a remarkable significance between signi ficance,acute renal failure group and normal control group(P<0.01),there is no significance between in chronic renal failure group and acute renal failure grou p.Conclusions:There is significant value for differentiating chronic renal failure and acute renal failure.

  16. Expression and Roles of Retinol-Binding Protein 4 in Patients with Gestational Diabetes Mellitus: a Prospective Study%视黄醇结合蛋白4在妊娠期糖尿病患者中的表达及其临床意义

    Institute of Scientific and Technical Information of China (English)

    王丹丹; 周洁; 杨玲; 周圆; 张炜; 周琳; 陈菊萍; 戴海燕; 赵一鸣; 罗晓红; 刘玲; 朱泰来; 羊伟瑾

    2011-01-01

    Objective:This study was performed to analysis the expression of retinol-binding protein 4 (RBP4) in serum of patients with gestational diabetes mellitus (GDM) and healthy pregnant woman? and the relationship between RBP4 and clinicopathological features of GDM patients. Methods: We prospectively collected and measured the serum RBP4 levels by enzymelinked immunosorbentassay (ELISA) of 18 patients with GDM and 212 healthy pregnant women at gestational weeks 18, 20,28, and postpartum weeks 8. The extent of insulin resistant was evaluated by homeostasis model assessment (HOMA-IR).Results: The serum RBP4 level presented a time-dependent increase in all pregnant women. The serum RBP4 level of GDM was higher than that of healthy pregnant women at gestational weeks 20 and 28. The serum RBP4 level had positive relations with HOMA-IR and fasting blood-glucose (FPG) at gestational weeks 20. Conclusions: The serum RBP4 level at gestational weeks 20 is potential to be an early diagnostic marker for GDM.%目的:分析视黄醇结合蛋白4(retinol-binding protein 4,RBP4)在妊娠期糖尿病患者和健康孕妇血清中的浓度差异及其与临床、病理特征的关系.方法:检测18例妊娠期糖尿病(GDM)和212例健康孕妇血清中RBP4的表达,分别于孕18周、孕20周、孕28周及产后8周空腹收集血清.利用酶联免疫吸附实验(ELISA)检测血清RBP4的表达.用HOMA-IR(homeostasis model assessment)模型评价胰岛素抵抗程度.结果:所有孕妇血清RBP4水平在产前各时间点呈时间依赖性升高.产后8周 (中位数,15.35 μg/mL;四分位数,11.32~27.85 μg/mL)孕妇血清RBP4水平均下降.孕20周(中位数,45.72 μg/mL;四分位数,33.34~58.69 μg/mL) 、孕28周(中位数,52.34 μg/mL;四分位数,42.65~73.54 μg/mL )时,GDM患者血清RBP4水平高于健康孕妇 (孕20周:中位数,19.13 μg/mL;四分位数,15.23~22.65 μg/mL;孕28周:中位数,42.54 μg/mL;四分位数,24.56~55.21 μg/mL).孕18周(中位数,16

  17. 血清视黄醇结合蛋白4对非糖尿病孕妇分娩巨大儿的预测价值%The Predictive Value of Serumal Retinol-Binding Protein 4 for Fetal Macrosomia of Non-Diabetic Pregnant Women

    Institute of Scientific and Technical Information of China (English)

    张保华; 冯晓丹; 沈卫; 余凤萍; 季静; 徐文怡; 王琴; 李岚; 郭洁

    2014-01-01

    Objective:To investigate the predictive value of serumal retinol-binding protein 4(RBP4) level fro fetal macrosomia of non-diabetic pregnant women .Methods :The serumal levels of RBP4 of 500 non-diabetic pregnant women at 12 week ,20 week and 24 week of pregnancy were measured by immune projection turbidimetric method .Fetal macrosomia was defined as birth weight≥4000 g .The cut-off value ,sensitivity and specificity were calculated with receiver operating characteristic (ROC) curve .Results:Of the 500 non-diabetic pregnant women ,30 cases(6% ) got fetal macrosomia .The ROC curve showed that the predictive cut-off values of RBP4 at 12 week ,20 week and 24 week of pregnancy were 61 .0 mg/L ,50 .5 mg/L and 52 .5 mg/L , respectively ;the predictive sensitivity and specificity at 12 week ,20 week and 24 week of pregnancy were 42 .9% and 94 .5% , 70 .0% and 69 .5% ,76 .9% and 73 .2% ,respectively .The predictive cut-off value of RBP4 no later than 24 week of pregnancy was 51 .5 mg/L ;the predictive sensitivity and specificity were 61 .8% and 69 .5% .There was significant difference(P<0 .05) between the serumal level of RBP4 at 24 week of pregnancy in group fetal macrosomia and that in group nonfetal macrosomia . Conclusions :The predictive sensitivity of RBP4 increases in accordance with the increase of serumal level of RBP 4 .The serumal level of RBP4 of non-diabetic pregnant women at 24 week of pregnancy may have higher sensitivity and specificity in the predic-tion of fetal macrosomia .If the serumal level of RBP4 no later than 24 week of pregnancy is beyond 50 mg/L ,then the risk of fetal macrosomia will be higher .%目的:探讨非糖尿病孕妇血清中视黄醇结合蛋白4(retinol-binding protein 4,RBP4)水平对巨大儿的预测价值。方法:采用免疫投射比浊法检测500例非糖尿病孕妇在不同孕周(孕12、20、24周)的血清RBP4水平,以出生体质量≥4000 g者为巨大儿。采

  18. Relationship between serum retinol-binding protein 4 and non-alcoholic fatty liver disease in schizophrenia%精神分裂症患者血清视黄醇结合蛋白4与非酒精性脂肪肝的关系

    Institute of Scientific and Technical Information of China (English)

    张书友; 孙剑; 余海鹰; 陈方斌; 张理义

    2014-01-01

    Objective To investigate the serum retinol-binding protein 4 (RBP4) level in olanzapinetreated schizophrenia with non-alcoholic fatty liver disease (NAFLD) via a case-control study and to explore its relationship with NAFLD.Methods Schizophrenia receiving olanzapine treatment,with or without NAFLD were enrolled as cases (n=60) or controls (n=60).The serum retinol-binding protein 4,metabolic syndrome component including body mass index (BMI),waist-to-hip ratio (WHR),fasting plasma glucose (FPG),total cholesterol (TG),total glycerin (TC) and blood pressure were assayed.TyG index,CT value ratio of liver and spleen were used for insulin resistance or NAFLD diagnosis and severity assessment respectively.Results The serum level of RBP4 was significantly higher in cases than that in controls ((70± 13)mg/L vs (52±12)mg/L ; t =4.943,P<0.01) and the same result was showed after influencing factor adjustment thru covariance analysis (F=16.797,P<0.01).Moreover,cases had significantly higher TyG index,BMI,WHR,FPG,TG and systolic pressure (t=2.383-4.300,P<0.05-0.01).Cases with severe or moderate NAFLD had significantly elevated serum RBP4 level compared with mild cases((79± 16) mg/L,(72±8) mg/L vs (63t9) mg/L,d =16.2,9.9 ; P<0.01,0.05).A significantly negative correlation between RBP4 level and the CT value ratio of liver and spleen (r=-0.244,P<0.05),and a significantly positive correlation between RBP4 level and TyG index,BMI,WHR,TG(r=0.197-0.244,all P<0.05) were observed.The partial coefficient between RBP4 level and CT value of liver and spleen was significant with influence adjusted(r=-0.453,P<0.01).Logistic regression showed that serum RBP4 level(β3=0.105,P<0.01)and TyG index,hyperlipidemia,obesity,central obesity or high blood pressure (β =1.288-9.711,P< 0.05-0.01) were closely associated with NAFLD.Conclusion A heighten serum RBP4 level may be one of NAFLD risk factors in schizophrenia treated with olanzapine.%目的 对精神分裂症伴发非酒

  19. 视黄醇结合蛋白和血清胱抑素C以及同型半胱氨酸在糖尿病肾损伤患者中的检测意义%Value for detection of Retinol-binding protein,serum cystatin C and ho-mocysteine in patients with diabetic renal injury

    Institute of Scientific and Technical Information of China (English)

    付小国; 卢爱国; 唐艳兰; 秦加巍

    2015-01-01

    Objective To explore the value for detection of retinol binding protein (RBP),serum cystatin C (CysC) and homocysteine (Hcy) in patients with diabetic renal injury. Methods 117 patients with type 2 diabetes in our hospital from March 2013 to December 2014 were randomly selected,according to the quantity of urinary protein,the patients were divided into group A (urine protein was less than 150 mg/24 h) and group B (urine protein was 150-300 mg/24 h). 56 normal physical examination human during the same period were selected as control group.The level change of RBP, CysC and Hcy among three groups was compared. Results The level of RBP,CysC and Hcy in group A and group B was higher than that in control group(P<0.05).With the progress of the disease,the level of RBP,CysC and Hcy in group A was higher than that in group B (P<0.05).There was significant difference about RBP,CysC,Hcy combination detection in group A or group B compared with RBP,CysC,Hcy detection separately in group A or group B (P<0.05). Conclusion Regular monitoring of RBP,CysC and Hcy for diabetic patients has important significance in early diagnosis of glomeru-lar filtration function damage in type 2 diabetic patients and reducing the occurrence of the disease.%目的:探讨视黄醇结合蛋白(RBP)和血清胱抑素C(CysC)以及同型半胱氨酸(Hcy)在糖尿病肾损伤患者中的检测意义。方法随机选取2013年3月~2014年12月117例2型糖尿病患者,根据尿蛋白定量分为A组(尿蛋白<150 mg/24 h)和B组(尿蛋白为150~300 mg/24 h)。选择同期正常体检者56例作为对照组。比较3组患者的RBP、CysC、Hcy水平变化。结果 A、B组患者的RBP、CysC、Hcy水平显著高于对照组(均P<0.05),随着病情进展,A组患者的RBP、CysC、Hcy水平显著高于B组(均P<0.05)。 A、B组RBP、CysC、Hcy联合检测与RBP、CysC、Hcy各项单独检测比较,差异有统计学意义(均P<0.05)。结论糖尿病患

  20. 非酒精性脂肪性肝病合并早发冠心病患者视黄醇结合蛋白4的检测及其意义%The detection and clinical significance of retinol-binding protein 4 in patients with non-alcoholic fatty liver diseases and premature coronary artery diseases

    Institute of Scientific and Technical Information of China (English)

    汤涌; 张晓峰; 郭忠玉; 李朝凤; 马根山

    2015-01-01

    Objective: To assess the correlation of retinol-binding protein 4 ( RBP4 ) and premature coronary artery disease in patients with non-alcoholic fatty liver diseases( NAFLD) .Methods:79 patients with NAFLD were selected for the study.With the help of coronary angiography, they were divided into two groups: premature coronary artery disease group with 49 patients and control group with 30 patients.Based on results of ultrasound examinations, they were further divided into three groups: mild fatty liver group, moderate fatty liver group and severe fatty liver group.Biochemical indexes, serum levels of RBP4 and C reactive protein were measured for correlation analysis in peripheral venous blood of the 79 patients.Results:Compared to the control group, serum levels of RBP4;C reactive protein,and LDL-C in premature coronary artery disease group had significantly larger increase( P<0.05 ) .The number of patients with coronary artery disease in severe fatty liver group, and serum levels of RBP4 in severe and moderate fatty liver groups increased significantly more than in themild fatty liver group( P<0.05 ) .Conclusion: For NAFLD patients, RBP4, which increases in premature coronary artery, is closely associated with the severity of fatty liver disease.%目的:观察非酒精性脂肪性肝病( NAFLD)患者血清视黄醇结合蛋白4( RBP4)水平与早发冠心病的相关性。方法:选择79例NAFLD患者,经冠状动脉造影分为早发冠心病组49例和对照组30例。患者再根据肝脏B超检查结果分为轻、中、重度脂肪肝组。所有患者均抽外周静脉血检测生化指标、RBP4和超敏C反应蛋白( hs-CRP)水平,并行组间比较。结果:与对照组比较,早发冠心病组血清RBP4、hs-CRP、LDL-C水平均明显增加,差异有统计学意义( P<0.05)。与轻度脂肪肝组比较,重度脂肪肝组合并冠心病人数增加,中度和重度脂肪肝组RBP4水平增加

  1. 2型糖尿病及糖尿病肾病患者视黄醇结合蛋白4检测的意义%Significance of retinol binding protein 4 in patients with type 2 diabetes mellitus and diabetic nephropathy

    Institute of Scientific and Technical Information of China (English)

    宁艳平

    2013-01-01

    Objective To investigate the changes and clinical significance of retinol binding protein 4 (RBP4) level in patients with type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN) .Methods According to uri-nary albumin excretion rate (UAER) ,118 T2DM cases were divided into simple diabetic mellitus group (SDM group ,47 cases) ,early DN group (EDN group ,40 cases) and clinical DN group (CDN group ,31 cases) .30 health-y subjects were enrolled as controls group (NC group) .Plasma level of RBP4 was examined by using enzyme linked immunosorbent assay with double antibody sandwich method .Results Compared with NC group ,plasma levels of RBP4 and high sensitive C-reactive protein (hs-CRP) in SDM ,EDN and CDN group were significantly increased (P<0 .05) ,which was more obvious as pathogenetic condition aggravated .Plasma RBP4 level was positively corre-lated with hs-CRP (r=0 .77 ,P<0 .01) .RBP4 level increased as urine level of microalbumin increased in T 2DM pa-tients .Conclusion Plasma level of RBP4 could be increased in patients with T2DM ,which might be taken as an early sensitive diagnostic marker for DN .%目的探讨2型糖尿病(T2DM)及其合并肾病(DN)患者血视黄醇结合蛋白4(RBP4)浓度变化及临床意义。方法根据尿清蛋白排泄率(UAER)将118例 T2DM 患者分为单纯糖尿病(SDM )组47例、早期糖尿病肾病(EDN )组40例和临床糖尿病肾病(CDN )组31例;另选30例健康体检者作为对照(NC )组。采用酶联免疫吸附试验双抗体夹心法检测RBP4。结果 SDM 、EDN、CDN组RBP4、超敏C-反应蛋白(hs-CRP)较NC组升高(P<0.05),随病情加重,升高更为明显。RBP4与hs-CRP高度相关(r=0.77,P<0.01)。T2DM 患者血浆 RBP4水平随着尿清蛋白的增加而升高。结论 T2DM 患者血浆RBP4水平明显升高,可作为DN早期的敏感的诊断指标。

  2. Study on levels of serum retinol and retinol-binding protein-4 in patients with pulmonary tuberculosis%肺结核患者血清视黄醇和视黄醇结合蛋白4水平变化的研究

    Institute of Scientific and Technical Information of China (English)

    麦洪珍; 杨智; 宋晓东; 蔡春葵; 路希维

    2015-01-01

    目的 检测耐药肺结核、非耐药肺结核患者和健康对照者血清维生素A(视黄醇)和视黄醇结合蛋白4(retinol-binding protein-4,RBP4)水平,并分析它们的影响因素.方法 收集2011年7月至2013年8月大连市结核病医院门诊随访及住院治疗的耐药肺结核患者128例(耐药组)、非耐药肺结核患者152例(非耐药组),匹配选取我院同期健康体检者120名作为对照组.采用高效液相色谱法(HPLC)测定上述受试者血清视黄醇水平,同时采用酶联免疫吸附测定法(ELISA)检测血清RBP4水平.结果以(-±s)表示,所有数据采用SPSS 15.0统计软件进行统计学分析.多组间比较采用单因素方差分析及SNK-q检验,以P<0.05为差异有统计学意义.影响因素分析采用直线相关和多元逐步回归分析.结果 耐药组、非耐药组患者血清视黄醇、RBP4水平分别为(206.10±10.35)μg/L、(6.22±1.64)μg/ml和(249.61±12.06)μg/L、(8.23±2.31)μg/ml,均显著低于对照组血清视黄醇、RBP4水平(326.57±11.52)μg/L、(11.52±2.60)μg/ml,差异均有统计学意义(q=12.35和10.66,P值均<0.01;q=3.86和3.36,P值均<0.05);而耐药组较非耐药组,患者血清视黄醇、RBP4水平均显著降低,差异均有统计学意义(q=3.25和3.12,P值均<0.05).多元逐步回归分析表明,体质量指数(BMI)是血清视黄醇和RBP4的独立影响因素(t=2.154和5.211,P值均<0.05).结论 肺结核患者血清视黄醇和RBP4水平均显著降低,耐药肺结核患者降低更明显.

  3. The study of serum retinol-binding protein 4 and related factors in chronic hepatitis C%慢性丙型肝炎患者血清视黄醇结合蛋白4水平及相关影响因素的研究

    Institute of Scientific and Technical Information of China (English)

    吴萍; 陈红; 李秋贞; 闫淑花; 范琦丽

    2010-01-01

    目的 探讨慢性丙型肝炎患者血清视黄醇结合蛋白4(RBP4)的水平及相关影响因素.方法 选择56例慢性丙型肝炎患者(观察组)及35例健康体检者(对照组),采用ELISA法测定空腹血清RBP4水平,并测定空腹血糖(FBG)、三酰甘油(TG)、总胆固醇(TC)、丙氨酸氨基转移酶(ALT)、γ谷氨酰转移酶(γ-GT),PCR法测定丙型肝炎病毒(HCV)-RNA水平.结果 两组FBG、TC、TG、γ-GT水平比较差异无统计学意义(P>0.05),观察组血清RBP4水平为(33.38±6.43)mg/L,明显高于对照组的(26.11±3.35)mg/L(P<0.01).ALT正常的观察组26例患者血清RBP4水平为(38.96±4.09)mg/L,明显高于ALT异常的观察组30例患者的(28.53±3.43)mg/L(P<0.01).观察组患者的ALT水平与RBP4水平呈负相关(r=-0.6368,P<0.05).结论 血清RBP4水平与慢性丙型肝炎有显著相关性,且与ALT呈负相关,与FBG、TC、TG、γ-GT及HCV-RNA无关.%Objective To investigate the level of serum retinol-binding protein 4 (RBP4) and related factors in chronic hepatitis C (CHC). Methods Fifty-six patients with CHC (CHC group) and 35 healthy volunteers (control group) were selected. Serum RBP4 level was measured by ELISA method.Fasting blood glucose ( FBG ), triglycerides (TG), total cholesterol ( TC ), alanine aminotransferase (ALT),γ-glutamyl transpeptidase (γ-GT) were measured, HCV-RNA level was tested by qualitative polymerase chain reaction(q-PCR). Results There were no significant difference in FBG, TC,TG, γ-GT between two groups (P > 0.05 ). Serum RBP4 level in CHC group [(33.38 ± 6.43 ) mg/L] was higher than that in control group [(26.11 ± 3.35) mg/L](P< 0.01),the CHC patients with ALT normal (26 cases) had significantly higher RBP4 level [( 38.96 ± 4.09) mg/L] compared with ALT abnormal [30 cases, ( 28.53 ± 3.43 ) mg/L](P < 0.01 ). ALT level was negative with RBP4 in CHC group (r = -0.6368, P < 0.05 ). Conclusion Serum RBP4 level is significantly associated with CHC and negatively

  4. 子宫内膜异位症患者RBP4与ENA-78的含量变化%Changes of Levels of Prostaglandin Retinol Binding Protein 4(RBP4)and Epithelial Neutrophil-Activing Peptide-78 (ENA-78)in Peritoneal Fluid and Serum of Patients with Endometriosis

    Institute of Scientific and Technical Information of China (English)

    张文敏; 赵艳丽; 班开斌; 黄友敏

    2012-01-01

    目的 探讨子宫内膜异位症(EMS)患者腹腔液及血清中视黄醇结合蛋白4(RBP4)和中性粒细胞激活肽-78(ENA-78)的含量变化及其与EMS发病的关系.方法 采用酶联免疫吸附法(EHSA)检测86例EMS患者和36例因卵巢囊肿或浆膜下子宫肌瘤手术患者腹腔液及血清RBP4和ENA-78含量并进行分析.结果 EMS组患者腹腔液中RBP4、ENA-78的含量明显高于对照组,两组比较差异均有统计学意义(P<0.01).Ⅲ、Ⅳ期EMS患者腹腔液及血清中RBP4的含量较Ⅰ、Ⅱ期患者明显升高,差异也有统计学意义(P<0.01);Ⅲ、Ⅳ期EMS患者腹腔液及血清中ENA-78的含量较Ⅰ、Ⅱ期患者升高,差异有统计学意义(P<0.05).同时EMS组患者RBP4与ENA-78的含量之间存在正相关(r=0.72,P<0.01).结论 EMS患者腹腔中高含量的RBP4与ENA-78,可能对EMS发病有影响;EMS患者腹腔液与血清中RBP4和ENA-78含量变化且与EMS关系密切.%Objective To investigate the concentrations of prostagland in retinol binding protein 4(RBP4) and epithelial neutrophil-activing peptide-78 (ENA-78) in serum and peritoneal fluid of women with endometriosis. Methods The study group included 86 samples of peritoneal fluid and serum respectively from patients with endometriosis, and control group included 36 samples of peritoneal fluid and serum respectively from patients without endometriosis(either ovary cyst or uterine myoma). The peritoneal fluids were collected at the time of laparoscopic operation, and the sera were collected before surgery. Concentrations of RBP4 and ENA-78 were determined by enzyme linked immunosorbent assay ( ELISA). Results The peritoneal fluid concentrations of RBP4 and ENA-78 in study group were significantly higher than those of control group(P <0.01 )>;and the RBP4 levels of stage HI , IV in endometriosis group were significantly higher than those of stage I , II in endometriosis group in serum and peritoneal fluid(P <0.01) ;and the ENA-78

  5. Relationship between the Serum Retinol Binding Protein 4 and Insulin Resistance in Nonalcoholic Fatty Liver Disease%非酒精性脂肪肝患者血清RBP4水平与胰岛素抵抗等相关性研究

    Institute of Scientific and Technical Information of China (English)

    张洪梅; 许华强; 张建武; 丁俊蓉; 陈艳

    2011-01-01

    Objective To investigate the level of serum retinol binding protein 4(RBP4) in patients with nonalcoholic fatty liver disease(NAFLD) and its relationship with obesity, insulin sensitivity, blood glucose, and blood lipid.Methods 64 patients with nonalcoholic fatty liver disease( NAFLD group) and 35 normal subjects( normal control group) were selected.The level of serum RBP4 was measured by ELISA.Height, weight, waist circumstance, hip girth, fasting blood glucose( FBG), blood lipid( TC,TG, HDL-C, LDL-C ), liver function ( AST, ALT), and fasting insulin (FINS) were measured.Body mass index ( BMI ), waist to hip ratio( WHR), homeostasis model assessment of insulin resistance(HOMA-IR) were calculated as well.Results Serum levels of FBG,TC,TG,LDL-C,FINS,RBP4 and HOMA-IR,BMI,WHR were higher in NAFLD patients as compared to normal controls ( P <0.01 ).And the moderate NAFLD group had higher FBG,TC,TG,LDL-C,FINS,RBP4 and HOMA-IR,BMI,WHR as compared with the mild NAFLD group( P < 0.01 ).Serum RBP4 were positively correlated with BMI, WHR, FBG, TC, TG, LDL-C,FINS and HOMA-IR(r=0.379,0.341,0.367,0.359,0.366,0.342,0.338,0.447,P <0.01 ).Conclusion Serum RBP4 was involved in the insulin resistance during the development of nonalcoholic fatty liver disease.%目的 探讨非酒精性脂肪肝患者血清视黄醇结合蛋白4(RBP4)及其与肥胖、胰岛素抵抗、血糖、血脂的关系.方法 选择非酒精性脂肪肝患者64例,正常对照35例,采用ELISA方法 测定空腹血清RBP4,同时检测其身高、体重、腰围、臀围、血糖、血脂、肝功能及胰岛素水平,并计算体重指数(BMI)、腰臀比(WHR)和胰岛素抵抗指数(HOMA-IR).结果 与正常对照组比较,轻、中度非酒精性脂肪肝患者的BMI、WHR、FBG、TC、TG、LDL-C、FINS、HOMA-IR和RBP4显著增高(P<0.01).相关分析显示,血清RBP4与BMI、WHR、FBG、TC、TG、LDL-C、FINS、HOMA-IR呈正相关.结论 在非酒精性脂肪肝的发病过程中,RBP4可能参与了胰岛素抵抗.

  6. 冠心病患者血清视黄醇结合蛋白4与高敏C反应蛋白的相关性分析%Study of the relationship between serum retinol binding protein 4 and high sensitive C-reactive protein in oatients with coronary heart disease

    Institute of Scientific and Technical Information of China (English)

    刘海亮; 李国庆

    2011-01-01

    Objective To evaluate the correlation of Retinol binding protein 4 ( RBP4), the high sensitivity C-reactive protein(hs-CRP) and coronary heart disease(CHD) by test the serum level of them.Methods Ninety patients with CHD were divided into the acute myocardial infarction(AMI) group( n =30), the unstable angina pectoris (UAP) group ( n = 30) and the stable angina pectoris(SAP) group ( n =30) ,30 normal subjects without CHD diagnosed by coronary arteriography(CAG) served as the control group. The serum level of RBP4 is measured by enzyme linked immune sorbent assay(ELISA) and the serum level of hs-CRP is measured by turbidmetricimmunoassay. Results The serum level of RBP4 and hsCRP were higher in AMI and UAP group that in SAP group and control group( P <0.05 ). The mean level of hs-CBP in SAP group was differently significantly,compared with that in control( P > 0.05 ). While the RBP4 is the opposite. The mean level of RBP4 or hs-CRP in single, double and three vessel lesion group were higher than that in control group( P < 0.05 ) ,but the serum levels of RBP4 or hs-CRP among single,double and three were not significant different( P > 0.05). The serum level of RBP4 and hs-CRP were significantly positive correlation in Spearman correlation coefficients ( r = 0. 469, P < 0.01 ). Conclusions RBP4 and hs-CRP may act as one of vulnerable plaques,and be correlated with CHD. However,may not reflect the severity of artery stenosiso%目的 测定冠心病患者血清视黄醇结合蛋白4(RBP4)和高敏C反应蛋白(hs-CRP)水平,分析两者与冠心病的相关性.方法 将90例冠心病患者分为急性心肌梗死组30例,不稳定性心绞痛组30例,稳定性心绞痛组30例,另选择30例冠状动脉造影结果正常者为对照组.采用酶联免疫吸附法测定受试者血清RBP4水平,采用增强免疫透射比浊法测定血清hs-CRP水平.结果 急性心肌梗死和不稳定性心绞痛组患者血清RBP4、hs-CRP水平高于稳定性心绞痛组

  7. 血清视黄醇结合蛋白4水平与2型糖尿病并发急性脑梗死的相关性研究%The study of the correlation of serum retinol binding protein 4 in type 2 diabetes mellitus patients combined with acute cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    曹灵; 张真稳; 朱妍

    2015-01-01

    目的:探讨血清视黄醇结合蛋白4(retinol-binding protein,RBP4)水平与2型糖尿病并发急性脑梗死的相关性。方法选取2014年6月-2015年1月在扬州大学医学院附属医院住院的30例2型糖尿病并发急性脑梗死患者、30例2型糖尿病并发陈旧性脑梗死患者、30例2型糖尿病不合并脑梗死患者、30例非糖尿病脑梗死患者及30例同期体检健康者。比较各组受检者的总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、脂蛋白(a)[LP (a)]、胱抑素C(Cyc-C)、空腹血糖(FPG)、糖化血红蛋白(HbA1c)、RBP4水平。采用Spearman相关分析RBP4的相关因素,采用二分类Logistic回归分析2型糖尿病并发急性脑梗死的影响因素。结果①5组受检者收缩压( SBP)、FPG、TG、HDL-C、Cyc-C、HbA1c、RBP4水平差异有统计学意义(P<0.05);其中2型糖尿病并发急性脑梗死组患者血清RBP4水平均高于对照组、2型糖尿病并发陈旧性脑梗死患者组、2型糖尿病患者组、脑梗死患者组。②Spearman相关分析显示,血清TG、Cyc-C水平均与RBP4呈正相关(r值分别为0.309和0.176,P值均<0.05),血清HDL-C水平与RBP4呈负相关(r值为-0.249,P<0.01)。③二分类Logistic回归分析显示,RBP4与2型糖尿病并发急性脑梗死存在回归关系(OR=1.188,P<0.05),收缩压(SBP)和舒张压(DBP)与2型糖尿病并发陈旧性脑梗死存在回归关系(分别为OR=1.133,P<0.01;OR=0.879,P<0.05)。结论高血清RBP4水平可能是2型糖尿病并发急性脑梗死的危险因子之一,血清RBP4升高与血脂偏高有关。%Objective To explore the relation between serum retinol binding protein 4 ( RBP4 ) level and type 2 diabetes mellitus patients combined with acute cerebral infarction.Methods The patients who were admitted to the Affiliated

  8. Clinical significance of retinol-binding protein detection for diagnosis of nephrotic syndrome in children%视黄醇结合蛋白检测在肾病综合征患儿诊断中的临床意义

    Institute of Scientific and Technical Information of China (English)

    李浩军; 孟秀荣; 董晓妮

    2014-01-01

    Objective To explore the clinical significance of retinol‐binding protein detection for diagnosis of nephrotic syndrome in children .Methods A total of 60 cases of children with nephrotic syndrome were enrolled in the experimental group and divided into two groups (33 cases for the simple type nephrotic syndrome group and 27 cases for the nephritic type nephrotic syndrome group) .And other 30 cases of healthy children were selected as the healthy control group .The levels of retinol‐binding protein ,urea and creatinine were detected and analyzed .Results The levels of serum retinol‐binding protein ,urea and creatinine were higher in two experimental groups than those in healthy control group ,and in the two experimental groups the positive detectable rate of serum retinol‐binding protein was higher than that of urea and creatinine ,all with significant difference(P< 0 .05) .The levels of serum retinol‐binding protein detected after treatment were evidently higher than those detected before treatment(P<0 .05) ,and a certain correlation was found between levels of serum retinol‐binding protein and the clinical feature (r=0 .799 3 ,P<0 .05) .The diagnostic efficiency of retinol‐binding protein was the highest ,followed by urea and creatinine .Conclu‐sion The retinol binding protein detection could be with positive clinical value for the clinical diagnosis and thera‐peutic morniteration of children with nephrotic syndrome .%目的:探讨视黄醇结合蛋白检测在肾病综合征患儿诊断中的临床意义。方法选择2013年1~12月在涿州市中医院确诊为肾病综合征的患儿60例为试验组(单纯型肾病综合征组33例,肾炎型肾病综合征组27例),另选择30名健康儿童设为健康对照组,分别测定其血清视黄醇结合蛋白、尿素和肌酐水平并进行比较分析。结果试验组两组患儿的血清视黄醇结合蛋白、尿素和肌酐浓度水平均高于健康对照组,且试验组

  9. Integrating protein structures and precomputed genealogies in the Magnum database: Examples with cellular retinoid binding proteins

    Directory of Open Access Journals (Sweden)

    Bradley Michael E

    2006-02-01

    Full Text Available Abstract Background When accurate models for the divergent evolution of protein sequences are integrated with complementary biological information, such as folded protein structures, analyses of the combined data often lead to new hypotheses about molecular physiology. This represents an excellent example of how bioinformatics can be used to guide experimental research. However, progress in this direction has been slowed by the lack of a publicly available resource suitable for general use. Results The precomputed Magnum database offers a solution to this problem for ca. 1,800 full-length protein families with at least one crystal structure. The Magnum deliverables include 1 multiple sequence alignments, 2 mapping of alignment sites to crystal structure sites, 3 phylogenetic trees, 4 inferred ancestral sequences at internal tree nodes, and 5 amino acid replacements along tree branches. Comprehensive evaluations revealed that the automated procedures used to construct Magnum produced accurate models of how proteins divergently evolve, or genealogies, and correctly integrated these with the structural data. To demonstrate Magnum's capabilities, we asked for amino acid replacements requiring three nucleotide substitutions, located at internal protein structure sites, and occurring on short phylogenetic tree branches. In the cellular retinoid binding protein family a site that potentially modulates ligand binding affinity was discovered. Recruitment of cellular retinol binding protein to function as a lens crystallin in the diurnal gecko afforded another opportunity to showcase the predictive value of a browsable database containing branch replacement patterns integrated with protein structures. Conclusion We integrated two areas of protein science, evolution and structure, on a large scale and created a precomputed database, known as Magnum, which is the first freely available resource of its kind. Magnum provides evolutionary and structural

  10. Relationship between the Level of Serum Retinol-Binding Protein 4 and the Extent of Coronary Lesions in Coronary Heart Disease Accompanied with Type 2 Diabetes Mellitus%冠心病合并2型糖尿病血清视黄醇结合蛋白4水平与冠状动脉病变程度的相关性研究

    Institute of Scientific and Technical Information of China (English)

    张敏; 唐荣珍; 曹晓红; 张维; 辜晓惠; 董巍

    2011-01-01

    Objective To explore the relationship between the level of serum retinol-binding protein 4 (RBP4) and the extent of coronary lesions in coronary heart disease (CHD) patients accompanied with type 2 diabetes mellitus (T2DM). Methods A total of 120 patients with CHD diagnosed by coronary arteriongraphy between October 2008 and April 2010 were enrolled. The patients were divided into two groups: CHD group (60 patients); CHD accompanied with T2DM group (60 patients). The levels of serum insulin, adiponectin and RBP4 were measured. All the patients underwent coronary angiography and the extent of coronary lesions was assessed quantitatively based on the Gensini's scoring system. Results The levels of serum insulin, plasma RBP4 and the extent of coronary artery stenosis in CHD accompanied with T2DM group were significantly higher than those in CHD group (P<0. 05). Correlation analysis showed that the level of RBP4 was positively correlated with LDL-C, insulin resistance index and the coronary artery narrow degree(r=0. 312, 0. 322, 0. 314; P<0. 05); and negatively correlated with adiponectin (r=-0. 362, P<0. 01). Conclusion The significant elevated plasma RBP4 in CHD patients accompanied with T2DM is positively correlated with the extent of coronary artery lesion.%目的 研究合并2型糖尿病的冠心病患者冠状动脉病变程度与血清视黄醇结合蛋白4( retinol-binding protein 4,RBP4)水平的相关性.方法 2008年10月- 2010年4月选择性冠状动脉造影确诊的冠心病患者共120例,分为单纯冠心病组(A组)60例和冠心病合并糖尿病组(B组)60例,检测血糖、血脂、胰岛素以及脂联素、RBP4水平;根据冠状动脉造影结果,以Gensini评分评判冠状动脉病变程度.结果 B组空腹血糖、胰岛素、RBP4均显著高于A组(P<0.05);冠状动脉病变程度更重(P<0.05).相关性分析显示RBP4水平与低密度脂蛋白胆固醇、胰岛素抵抗和冠状动脉病变积分呈正相关(r=0.312、0.322

  11. Discuss the significance of serum retinol binding protein in nutritional status monitoring different during pregnancy%探讨血清视黄醇结合蛋白在不同孕期中营养状况监测的意义

    Institute of Scientific and Technical Information of China (English)

    邓修利

    2015-01-01

    Objective Discuss of serum retinol binding protein (RBP)level in pregnancy in the process of change, scientific guidance in different periods of pregnancy pregnant women nutritional level control to provide laboratory ba-sis.Methods Selection of 182 cases hospitalized in our hospital obstetrics and gynecology clinic for prenatal examina-tion and cards delivery of pregnant women,according to the gestation week number for early pregnancy,women in the late group RBP and traditional nutritional status evaluation index of Prealbumin (PA),albumin (ALB)and hemoglobin (HGB)water level test,and the control group (healthy women)testing results were statistically analyzed,and RBP in different pregnancy in testing of abnormal results were analyzed.Results Pregnancy early,middle and late group of RBP levels higher than the control group,the difference is statistically significant or highly significant (P 0.05);pregnancy,late group PA,ALB,HGB level of detection is lower than that of the control group,the difference has statistical significance (P < 0.05).When pregnant women body obvious changes in blood volume.Conclusion Serum RBP are good indicators of monitoring in different periods of pregnancy pregnant women nutritional status,serum levels of RBP level can provide valuable laboratory basis for the pregnancy period preg-nant women to evaluate the nutritional status of the body.The level of serum RBP trends are consistent with pregrant women to nutrition.%目的:探讨血清视黄醇结合蛋白(RBP)水平在妊娠过程中变化,为科学指导不同孕期的孕妇控制营养水平提供实验室依据。方法选择182例在本院妇产科门诊行孕期体检和建卡分娩住院的孕妇,对按妊娠周数分为妊娠早、中、晚期组的孕妇进行 RBP 和传统营养状况评价指标前白蛋白(PA)、白蛋白(ALB)和血红蛋白(HGB)水平检测,与对照组(健康体检妇女)检测结果进行统计学分析,并对 RBP 在不同

  12. 慢性阻塞性肺疾病患者血清维生素A和视黄醇结合蛋白-4水平及其与营养状况的关系%Serum retinol and retinol binding protein-4 levels in patients with chronic obstructive pulmonary disease and their relationship to nutritional status

    Institute of Scientific and Technical Information of China (English)

    麦洪珍; 王秋月; 韩丽萍; 康健; 于润江

    2009-01-01

    目的 探讨COPD患者血清维生素A和视黄醇结合蛋白-4(RBP_4)水平及其与营养状况的关系.方法 2006年9月至2007年9月在中国医科大学附属第一医院门诊随访的110例COPD稳定期患者为COPD组,同期90例健康体检者为对照组,采用高效液相色谱法测定所有研究对象的血清维生素A水平,采用酶联免疫吸附试验检测COPD组中62例和对照组中20例的血清RBP_4水平.计数资料采用X~2检验,两组间均数比较采用t检验,多组间比较采用单因素方差分析及SNK-q检验,影响因素分析采用直线相关和多元逐步回归分析.结果 COPD组血清维生素A和RBP_4水平分别为(275±11)μg/L和(7.4±2.6)mg/L,明显低于对照组的(338±13)μg/L和(11.4±4.1)mg/L;COPD营养不良组血清维生素A和RBP_4水平分别为(246±18)μg/L和(6.4±1.0)mg/L,明显低于COPD营养正常组的(290±14)μg/L和(8.2±3.2)mg/L.COPD患者血清维生素A和RBP_4水平均与体重指数和上臂围呈显著正相关(r值为0.210~0.469,均P<0.05和P<0.01).体重指数和上臂围是COPD)患者血清维生素A的独立影响因素.结论 COPD稳定期患者血清维生素A和RBP_4水平均明显降低,营养状况是其主要影响因素.%Objective To explore the serum retinol and retinol binding protein-4 (RBP_4) levels in patients with chronic obstructive pulmonary disease (COPD) and to investigate their relationship with the nutritional status. Methods The serum retinol level was determined by high-performance liquid chromatography (HPLC) in 110 outpatients with stable COPD during Sept 2006 to Sept. 2007, and 90 healthy volunteers served as the controls. The serum RBP_4 level in 62 stable COPD outpatients and 20 healthy controls was measured by enzyme-linked immunosorbent assay ( ELISA ). Associated factors with the serum retinol and RBP_4 levels were analyzed, t-test and one-way ANOVA were used for the statistic analysis. Results The serum retinol and RBP_4 levels in COPD patients

  13. 人视黄醇结合蛋白4水平升高与冠心病及其预后相关%Elevated plasma levels of retinol-binding protein-4 are associated coronary artery disease and one-year prognosis

    Institute of Scientific and Technical Information of China (English)

    谢芳艺; 陈忠; 丁震; 范沛英; 王鑫; 冯毅; 马根山

    2012-01-01

    Objective: To examine whether plasma levels of retinol-binding protein-4 (RBP4) are associated with coronary artery disease (CAD) and one-year prognosis. Methods: RBP4 levels were determined by ELISA kit (IBL. Germany) in 140 patients without type 2 diabetes undergoing coronary angiography for the concern of CAD. Patients were divided into controls (normal coronary arteries, n =46) and CAD (≥50% diameter stenosis, n = 94). CAD patients were followed up for average 12 months. Major adverse cardiac events (MACEs) including recurrent anginal, recurrent infarction, deteriorated heart failure and cardiac death were analyzed. Multivariate analysis was done to determine the association between RBP4 and composite MACEs during one- year follow up. Results: Compared to the controls, patients with CAD were older, had higher prevalence of hypertension and smokers (all P <0. 05). Meanwhile, patients suffering from MACEs (n = 8) had higher levels of RBP4 than those without [ (76. 12 ± 42. 89) μg·ml-1 vs (46. 24 ± 17. 66) μg·ml-1 , P <0. 01 ] ; these patients suffering from MACEs had higher ratio of RBP4 levels 3=70 μg · ml-1 than those without (37.50% vs 9.30%, P =0.018). Multivariate analysis demonstrated that RBP4 was an independent predictor of composite MACEs during one-year follow up ( OR: 1. 091 , 95% CI:1.015-1. 172, P =0. 018) . Conclusion-. RBP-4 levels are associated with CAD and one-year prognosis. Patients with higher RBP-4 levels are at higher risk of MACEs.%目的:研究人视黄醇结合蛋白4 (RBP4)水平与冠心病及1年预后关系.方法:选择因疑诊冠心病而行冠状动脉造影的140例非糖尿病患者,其中确诊冠心病患者94例,非冠心病患者46例(作为对照).采用ELISA试剂盒(德国IBL公司)检测140例患者血浆RBP4水平.冠心病患者出院后完成1年随访,记录主要不良心脏事件(MACEs),即再发心绞痛、再发心肌梗死、心力衰竭恶化和心源性死亡.多变量回归分析RBP4与1年随

  14. 妊娠肥胖、妊娠期糖尿病患者血清视黄醇结合蛋白4水平的变化及其相关影响因素%Change of Serum Retinol-binding Protein-4 Level in Pregnancy Obese Subjects and GDM and Related Factors

    Institute of Scientific and Technical Information of China (English)

    陈震宇; 杜鹃

    2011-01-01

    目的 探讨妊娠肥胖、妊娠期糖尿病(GDM)患者血清视黄醇结合蛋白4(RBP-4)水平变化及其相关影响因素.方法 采用酶联免疫吸附法检测24例孕前BMI≥28 kg/m,孕期体质量增加<20 kg的GDM孕妇(孕前肥胖GDM组,A组);28例孕前BMI 18.5~23.9 kg/m2,孕期体质量增加<20 kg的GDM孕妇(孕前非肥胖GDM组,B组);23例孕前BMI≥28 kg/m2,孕期体质量增加<20kg,无任何妊娠并发症的孕妇(单纯肥胖孕妇组,C组);23例孕前BMI 18.5~23.9 kg/m2,孕期体质量增加<20 kg的正常健康孕妇(正常对照组,D组)血清RBP-4、肿瘤坏死因子α(TNF-α)、脂联素(APN)水平;同时测定所有受试者的糖、脂生化指标,并计算胰岛素抵抗指数(HOMA-IR).结果 (1)A组孕妇FINS、HOMA-IR明显高于其他3组(P<0.01),B组孕妇FINS、HOMA-IR高于C组及D组(P<0.05),C组孕妇血清FINS、HOMA-IR高于D组(P<0.01);(2)A组孕妇血清RBP-4水平明显高于其他3组孕妇(P<0.05),C组孕妇血清RBP-4水平高于B组及D组(P<0.05);(3)血清RBP-4与舒张压、孕前BMI、FINS、HOMA-IR、TNF-α正相关,与APN负相关(r值分别为0.274,0.667,0.500,0.435,0.528,-0.386,P均<0.05);(4)多元逐步回归分析显示孕前BMI、TNF-α是血清RBP-4的独立相关因素(P<0.05).结论 GDM孕妇存在胰岛素抵抗,孕前肥胖的孕妇无论是否合并有GDM,其血清RBP-4水平均明显升高,血清RBP-4水平与肥胖密切相关,脂肪细胞因子之间相互抑制或相互促进,参与肥胖或GDM的发生.%Objective To investigate the change of serum retinol binding protein 4 (RBP-4) levels in obesity pregnant women and pregnant women with GDM and to investigate it's impact factors.Methods Serum RBP-4 levels,TNF-ot,APN,were measured by EnzymeLinked Immuno Sorbent Assay(ELISA) in 24 cases of GDM with obesity,28 cases of GDM with normal weight,23 cases of obesity pregnant women without pregnancy complications and 23 cases of normal weight pregnant women

  15. Determination of serum visfatin and retinol binding protein 4 ( RBP4 ) in patients with idiopathic sudden sensorineural hearing loss and its clinical significance%突发性耳聋患者内脂素和RBP4含量变化的研究

    Institute of Scientific and Technical Information of China (English)

    牛善利; 黄友敏; 周永勤

    2012-01-01

    Objective To study the role and clinical significance of serum visfatin and retinol binding protein 4 (RBP4) in idiopathic sudden sensorineural hearing loss by measuring the change of their levels in the patients with idiopathic sudden sensorineural hearing loss.Methods The levels of visfatin and RBP4 were determined by ELISA method in the 102 idiopathic sudden sensorineural hearing loss patients who were observed at two different time points ( before and after treatment),and thirty-five patients with other neurologic diseases (20 with sciatica,16 with trigeminal neuralgia) and thirty healthy people were used as control.Results The levels of visfatin and RBP4 in the serum of patients with idiopathic sudden sensorineural hearing loss after treatment [Visfatin (24.26 ± 2.17 ) μg/L; RBP4 (46.65 ± 5.26 ) mg/L]were markedly higher than the group with other neurologic diseases [Visfatin ( 20.67 ± 2.14 ) μ g/L; RBP4(34.37 ±5.73)mg/L] and the healthy control group[Visfatin(17.61 ±2.45) μg/L; RBP4 (24.82 ±5.24)mg/L] ( t =10.38,10.41,12.16,15.06,P <0.01),and it was significantly less than that before treatment [Visfatin(32.24 ± 2.37) μ /L; RBP4 ( 57.43 ± 6.19 ) mg/L] ( t =17.25,15.12,P < 0.01 ).The levels visfatin and RBP4 in serum of severe group with idiopathic sudden sensorineural hearing loss [Visfatin ( 36.52 ± 2.46 ) μg/L; RBP4 (67.17 ± 5.92 ) mg/L] were markedly higher than those in the moderate group[Visfatin(28.92 ±2.26)μg/L; RBP4 (55.34±5.95)mg/L]( t =11.21,11.17,P <0.01).The levels visfatin and RBP4 in serum of moderate group were markedly higher than those in the mild group [Visfatin ( 25.31 ± 2.32 ) μg/L; RBP4 ( 47.48 ± 5.82 ) mg/L],all these differences were statistically significant( t =10.43,10.49,P <0.01 ).There was a positive correlation between visfatin and RBP4 in patients with idiopathic sudden sensorineural hearing loss ( r =0.68,P < 0.01 ).Conclusions The levels of serum visfatin and RBP4 have instructive significance in

  16. Níveis plasmáticos de vitamina A, carotenóides e proteína ligadora de retinol em crianças com infecções respiratórias agudas e doenças diarréicas Plasma levels of vitamin A, carotenoids and retinol binding protein in children with acute respiratory infections and diarrhoeal diseases

    Directory of Open Access Journals (Sweden)

    Gustavo Velasquez-Melendez

    1994-10-01

    Full Text Available Planejou-se um estudo com o objetivo de se avaliar os níveis plasmáticos de vitamina A, carotenóides e proteína ligadora de retinol (RBP em 311 crianças, de 7 meses a onze anos de idade, com história de infecções das vias aéreas superiores (IVAS, pneumonia e diarréia, residentes na área urbana da Cidade de São Paulo, Brasil, e atendidas no serviço de pediatria de um hospital-escola. As dosagens de vitamina A e carotenóides realizaram-se pelo método de Neeld-Pearson e o RBP pelo método de Mancini. Os níveis plasmáticos de vitamina A (µg/dl e RBP (mg/dl foram mais baixos (pThe present study was carried out in order to assess the plasma levels of vitamin A, carotenoids and retinol binding protein (RBP of three-hundred and eleven children aged from seven months to eleven years, who had a history of upper respiratory infection (URI, pneumonia and diarrhoea. The children were resident in the urban area of the Municipality of S. Paulo, Brazil, and were seen at the pediatric service of the one school-hospital. The data show that plasma vitamin A (µg/dl and RBP (mg/ dl levels in the diarrhoea (15.2 µg/dl; 1.7 mg/dl and pneumonia (15.2 µg/dl; 0.7 mg/dl groups were lower (p<0.05 than those observed in the control (18.8 µg/dl; 2.6 mg/dl and URI (19.0 µg/dl; 2.4 mg/dl groups. The plasma carotenoid levels were lower in all groups than in the control group (p<0.05. These findings corroborate the results that show low levels of vitamin A in circulation during period of infection.

  17. Advanced Developments of Electron Spin Labeling as High-Resolution Sensors of Protein Structure and Conformational Switching

    Science.gov (United States)

    2007-11-02

    Myoglobin (Myb) and Cellular Retinol Binding Protein (CRBP) were prepared, and the corresponding EPR spectra analyzed by simulation techniques. In...unprecedented level of sophistication in interpretation of the EPR spectra of labeled proteins, and establish the feasibility of separating structural and...protein as well as local structure, but to date the level of interpretation has been largely qualitative and it has not been possible to separate the

  18. 血清中β2微球蛋白、视黄醇结合蛋白、胱抑素C在替诺福韦或恩替卡韦单药治疗慢性乙型肝炎早期肾功能变化中的意义%Changes in serum β2-microglobulin, retinol-binding protein, and cystatin C and their value in identifying early renal dysfunction in patients with chronic hepatitis B undergoing tenofovir or entecavir monotherapy: a comparative analysis

    Institute of Scientific and Technical Information of China (English)

    何佳; 宁会彬; 曾艳丽; 李威; 李宽; 尚佳

    2016-01-01

    Objective To investigate the dynamic changes in serum β2-microglobulin,retinolbinding protein,and cystatin C in chronic hepatitis B (CHB) patients treated with tenofovir or entecavir alone as the anti-HBV therapy,as well as their value in identifying early renal dysfunction.Methods A total of 61 previously untreated CHB patients who were diagnosed and treated in the Department of Infectious Diseases in Henan Provincial People's Hospital from June 2013 to August 2015 were enrolled and divided into tenofovir group and entecavir group.The serum levels of β2-microglobulin,retinol-binding protein,cystatin C,and creatinine and estimated glomerular filtration rate (eGFR) were compared between the two groups at baseline and 4,8,39,52,78,and 104 weeks after antiviral therapy.The independent samples t-test was used for comparison of continuous data,and the chi-square test was used for comparison of categorical data.P < 0.05 was considered statistically significant.Results A total of 61 CHB patients were enrolled,with 31 in the tenofovir group and 30 in the entecavir group.The two groups had comparable serum levels of β2-microglobulin,retinol-binding protein,and cystatin C at baseline,but there were significant differences in β2-microglobulin and retinol-binding protein over time (both P < 0.05).There was a significant difference in cystatin C at 78 weeks (t =-2.062,P =0.044),but there was no significant difference at 104 weeks (t =-1.544,P=0.128).There were no significant differences in serum creatinine or eGFR at any time point between the two groups (P > 0.05).At 104 weeks,there were no significant differences in HBV-DNA clearance rate or the level of virologic breakthrough between the two groups (P > 0.05).Conclusion Serum β2-microglobulin,retinol binding protein,and cystatin C are more sensitive than eGFR in the monitoring of early renal dysfunction during the anti-HBV therapy with tenofovir or entecavir alone.%目的 比较单用替诺福韦或恩替卡韦

  19. 新诊断2型糖尿病患者血清视黄醇结合蛋白4和游离脂肪酸水平变化及其与胰岛素敏感性的关系研究%Changes of Serum Retinol Binding Protein 4 and Free Fatty Acids Levels among Newly Diagnosed Type 2 Diabetic Patients and the Correlations with Insulin-sensitivity

    Institute of Scientific and Technical Information of China (English)

    潘佳秋; 王慧慧; 张超; 于学静; 姜飞飞

    2011-01-01

    Objective To explore the levels of serum retinol binding protein 4 ( RBP4 ) and free fatty acids ( FFA ), as well as the relationships between RBP4 level, FFA level and insulin - resistance index ( ISI ) in newly diagnosed type 2 diabetic patients.Methods Both Newly diagnosed type 2 diabetes patients ( T2DM, n = 76 ) and healthy subjects ( NC, n = 30 ) were enrolled grouping this study, with their serum levels of RBP4 and FFA measured.Also, insulin resistance index ( HOMA -IR ) and insulin sensitivity ( ISI) were calculated in both groups.Results ( 1 ) Serum levels of RBP4 and FFA in the T2DM group were significantly higher than in the control group ( P <0.01 ).(2) Single - factor correlation analysis showed that serum RBP4 was positively correlated with BMI, triglyceride ( TG ), cholesterol ( TC ), HOMA - IR and FFA and negatively correlated with ISI and HOMA - 尾 ( P < 0.05 ).(3) Multielement stepwise regression analysis discoveryed that HOMA - 尾 and FFA were independent risk factors of elevated RBP4 levels.Conclusion Serum RBP4 and FFA levels are significantly elevated among T2DM patients.The high expression level of serum RBP4 is associated with glucose and lipid metabolism which in turn leads to the development of IR and contributes to the pathogenesis of type 2 diabetes.RBP4 and FFA might be synergistic factors in emergence the insulin resistance.%目的 探讨新诊断2型糖尿病(T2DM)患者血清视黄醇结合蛋白4(RBP4)和游离脂肪酸(FFA)的表达水平以及二者与胰岛素敏感性的关系.方法 选取新诊断T2DM患者76例(T2DM组)及健康体检者30例(对照组).观察各组空腹血清RBP4和FFA水平,并计算胰岛素抵抗指数(HOMA-IR)、胰岛素敏感性指数(ISI)用以评价各组胰岛素敏感性.结果 (1)T2DM组患者血清RBP4和FFA水平显著高于对照组(P<0.01).(2)单因素相关分析显示,血清RBP4与体质指数(BMI)、三酰甘油(TG)、总胆固醇(TC)、HOMA-IR、FFA呈正相

  20. 视黄醇结合蛋白4和脂蛋白相关磷脂酶A2水平与冠心病及冠状动脉病变特征的相关性分析%The relationships between the levels of retinol binding protein 4 and lipoprotein associated phospholipase A2,and coronary heart disease and coronary artery lesion characteristics

    Institute of Scientific and Technical Information of China (English)

    葛玲; 程训民; 杨松; 唐杨章; 谢义民

    2015-01-01

    Objective:To investigate the relationships between the levels of retinol binding protein 4 ( RBP4 ) and lipoprotein associated phospholipase A2 ( Lp-PLA2 ) , and stability of deterioration of coronary heart disease and selective coronary angiography results. Methods:Eighty-nine patients with coronary heart disease were divided into the control group( without vessel lesion) ,1 vessel lesion group,2 branches lesion group and 3 branches lesion group according to the results of coronary angiography. The levels of Lp-PLA2 and RBP4 in 4 groups before angiography were detected by enzyme-linked immunosorbent assay. Results:The levels of Lp-PLA2 and RBP4 in 3 branches lesion group were significantly higher than those in control group,1 vessel lesion group and 2 branches lesion group(P0. 05). The difference of the RBP4 levels between 1 branch lesion group,2 branches lesion group 2 and control group were not statistically significant(P >0. 05). Conclusions:The levels of serum Lp-PLA2 and RBP4 in patients with coronary heart disease are related to the number of coronary artery lesion,which can predict the stenosis degree of coronary artery in a certain extent.%目的::探讨血清视黄醇结合蛋白4(RBP4)、脂蛋白相关磷脂酶A2(Lp-PLA2)水平与冠心病的稳定性、恶化及选择性冠状动脉(冠脉)造影结果的关系。方法:将89例冠心病患者根据冠脉造影结果分为4组,造影结果正常者14例为对照组,异常者根据冠脉病变支数,分为单支病变组22例,2支病变组21例和3支病变组32例。于造影前采集血标本,酶联免疫吸附法分别定量测定4组患者Lp-PLA2、RBP4水平。结果:3支病变组患者血清RBP4和Lp-PLA2水平均明显高于对照组、单支和2支病变组(P0.05),单支和2支病变组及对照组血清RBP4水平差异均无统计学意义(P>0.05)。结论:冠心病患者血清Lp-PLA2、RBP4水平与冠脉病变支数有关,可以在一定程度上反映冠脉的狭窄程度。

  1. 尿β2-微球蛋白与视黄醇结合蛋白及N-乙酰-β-D-氨基葡萄糖苷酶诊断成人心脏术后早期急性肾损伤的价值%Value of urine β2-microglobulin, urine retinol binding protein and N-acetyl-β-D-glucosaminidase to the diagnosis of early acute kidney injury after heart surgery in adult patients

    Institute of Scientific and Technical Information of China (English)

    刘红; 尹传妍; 刘颖; 陆晨; 岳华; 陶建双

    2016-01-01

    目的 探讨尿β2-微球蛋白(β2-microglobulin, β2-MG)、尿视黄醇结合蛋白(retinol-binding protein, RBP)、尿N-乙酰-β-D-氨基葡萄糖苷酶(N-acetyl-β-D-glucosa minidase, NAG)在成人心脏手术后急性肾损伤(acute kidney injury, AKI)早期诊断中的价值.方法 行心脏手术患者60例,分别于术前及术后24、48、72 h采用ELISA法检测尿β2-MG、 RBP水平,采用对硝基苯酚比色法检测尿NAG水平,采用酶法检测血清肌酐(serum creatinine, SCr).以术后48 h血清SCr较基础值增加≥50%为AKI判定标准,将60例患者分为AKI组41例,非AKI组19例,比较2组手术前、后尿β2-MG、RBP、 NAG水平变化;绘制ROC曲线,以AUC评价各标志物诊断AKI的效能.结果 2组术前尿β2-MG、 RBP、 NAG水平比较差异均无统计学意义(P>0.05), AKI组术后24、48、72 h尿β2-MG[(1.010±0.137)、(1.803±0.278)、(0.783±0.619)mg/L]、RBP[(0.384±0.336)、(0.468±0.418)、(0.383±0.359)mg/L]、 NAG[(29.276±23.406)、(33.275±26.175)、 (36.404±22.903)u/L]及血清SCr[(71.529±18.666)、 (91.930±32.017)、 (89.135±44.988)μmol/L]较非AKI组[β2-MG(0.168±0.150)、(0.227±0.155)、(0.160±0.124)mg/L,RBP(0.228±0.165)、(0.150±0.147)、(0.138±0.118)mg/L,NAG(10.441±5.535)、(13.900±8.243)、(11.940±6.307)u/L,SCr(64.517±17.392)、(68.761±20.176)、(64.268±19.119)μmol/L]明显增高,差异均有统计学意义(P<0.01);术后48 h尿β2-MG的AUC最大为0.822,95%CI:0.765~0.890,尿RBP的AUC为0.778,95%CI:0.701~0.878;术后72 h尿NAG的AUC最大为0.850,95%CI:0.774~0.927.结论 成人心脏手术后发生AKI者尿β2-MG、 RBP及NAG水平明显增高;尿β2-MG、RBP诊断心脏手术后AKI的最佳时间点为术后48 h,尿NAG为术后72 h.

  2. The difference of urinary N-acetyl-β-D-glucosaminidase and retinol binding protein before and after coronary angingraphy and their predictive values in contrast induced nephropaty%尿N-乙酰-β-D氨基葡萄糖酐酶和视黄醇结合蛋白在冠状动脉介入术后的变化及早期预测造影剂肾病的价值

    Institute of Scientific and Technical Information of China (English)

    王玲; 倪兆慧; 何奔; 刘建平; 杜勇平; 宋玮; 卜军; 戴惠莉; 吴青伟

    2009-01-01

    Objective To prospectively study the difference of urinary N-acetyl-β-D-glucosaminidase( UN-AG) and retinol binding protein(URBP) in contrast-induced nephropathy (CIN). Methods The clinical data of 150 patients undergoing coronary angiography were documented. The urine and blood samples before,24 hours after and 48~72 hours after the procedure were collected;Serum creatinine (SCr) and urinary ereatinine (UCr)were tested by enzymic method. UNAG and URBP were tested by ELISA in CIN and control group. CIN was defined as an increase in SCr of ≥44 μmol/L or >25% from baseline 48 ~72 h after the procedure. 27 age- , sex- , results of coro-nary angiography-matched cases were taken as control group. Results CIN was diagnosed in 13 of 150 patients (8.7%). In CIN group, UNAG/UCr were significantly higher than that in control group[ 1.97 (1.06,2.64) U/mmol vs 1.07 (0, 68,1.88 ) U/mmol, Z = 2.076, P = 0.039 ] before ;24 hours after the procedure, UNAG/UCr was signifi-cantly up-regulated in CIN group from baseline level [ 2.82 ( 1.88 ,4.26) U/mmol vs 1.97 (1.06,2.64) U/mmol, Z =2.607,P =0. 009]. ROC curve analysis showed that baseline UNAG could be used as an early predictor for CIN, the AUC =0. 776 ,P =0.023 ;when cut off value = 8.08 U/L,the sensitivity and specificity of UNAG were 0. 771 and 0. 713 respectively. The percentage of patients of UNAG over 8.08 U/L in CIN group was significantly higher than that in control group[77.1% (10/13) vs 29.6% (8/27) ,Z =2. 564,P =0. 011 ] ,the related risk factor is 5.58,95% CI was 1.24 ~ 25.08. Conclusion UNAG could be used as a predictor of CIN before the procedure and its postprocedure 24 h level maybe useful in early diagnosis after the procedure.%目的 前瞻性研究冠状动脉介入诊疗术后,尿N-乙酰-β-D氨基葡萄糖酐酶(UNAG)和尿视黄醇结合蛋白(URBP)在造影剂所致急性肾损伤发生前后的差异.方法 收集150例接受冠状动脉造影及介入治疗患者的临床资

  3. 慢性心力衰竭患者血浆视黄醇结合蛋白、胱抑素、NT-proBNP 浓度与体质量指数的关系%Relationship among plamsa retinol binding protein, cystatin C, N-teminal pro-brain natriuretic peptides levels with body mass index in patients with chronic heart failure

    Institute of Scientific and Technical Information of China (English)

    古忆; 卢新政; 周建松; 夏思良; 黄红娟; 郑宏健; 秦晓毅; 曹克将; 黄峻

    2011-01-01

    目的 探讨慢性心力衰竭患者血浆视黄醇结合蛋白(RBP)、胱抑素(Cys-C)、NT-proB-NP 浓度与体质量指数(BMI)的关系,及其对慢性心力衰竭患者心功能、预后评估的价值.方法 135例慢性心力衰竭患者(男70 例,女65 例,左心室射血分数28 kg/m2 ),测定慢性心力衰竭患者血浆RBP、Cys-C、NT-proBNP 浓度,探讨其与BMI 的相关性及其对慢性心力衰竭患者心功能、预后的影响.结果 (1)肥胖组患者血浆RBP 水平[(70.45 ±8.74)mg/L]明显高于BMI 正常组[(56.45 ±7.15)mg/L]及超重组[(64.61 ±7.24)mg/L],胱抑素水平[(2.78 ±0.38)mg/L]明显高于BMI 正常组[(1.90 ±0.48)mg/L]及超重组[(2.39 ±0.41)mg/L],血浆NT-proBNP 水平[(1536 ±69)ng/L]明显低于BMI 正常组[(1857 ±145)ng/L]及超重组[(1726 ±115)ng/L](P 均<0.01);(2)慢性心力衰竭患者血浆RBP、Cys-C 与BMI 之间存在显著正相关(r =0.621,P <0.01;r =0.680,P <0.01),且随肥胖程度加重而逐渐增高;NT-proBNP 与BMI 之间存在显著负相关(r =-0.865,P <0.01).结论 慢性心力衰竭患者血浆RBP、Cys-C 水平均随BMI 增加而增加,而NT-proBNP 随BMI 增加而降低,联合检测血浆NT-proBNP靇_氋;_岪、Cys-C、RBP 水平有利于肥胖合并慢性心力衰竭的诊断及预后评估.%Objective To explore the relationship among levels of plasma retinol binding protein , cystatin C,N-teminal pro-brain natriuretic peptide(NT-proBNP) with body mass index(BMI) ,and to identify whether the simultaneous determination of the three markers is valuable to evaluate the cardiac function and prognosis for patients with chronic heart failure. Methods 135 patients with chronic heart failure were enrolled in this study (70 males ,65 females and LVEF <50% ) ,and height and weight of each patient were measured and BMI were calculated with these parameter. The patients were divided into 3 groups according to BMI; normal group (BMI <24 kg/m2) , overweight group (BMI 24-27. 9 kg/m2) and obese group

  4. ING proteins in cellular senescence.

    Science.gov (United States)

    Menéndez, Camino; Abad, María; Gómez-Cabello, Daniel; Moreno, Alberto; Palmero, Ignacio

    2009-05-01

    Cellular senescence is an effective anti-tumor barrier that acts by restraining the uncontrolled proliferation of cells carrying potentially oncogenic alterations. ING proteins are putative tumor suppressor proteins functionally linked to the p53 pathway and to chromatin regulation. ING proteins exert their tumor-protective action through different types of responses. Here, we review the evidence on the participation of ING proteins, mainly ING1 and ING2, in the implementation of the senescent response. The currently available data support an important role of ING proteins as regulators of senescence, in connection with the p53 pathway and chromatin organization.

  5. Correlation between cystatin C,retinol-binding protein and pulmonary infection of patients with diabetes mellitus%糖尿病患者胱抑素C和视黄醇结合蛋白与肺部感染相关性研究

    Institute of Scientific and Technical Information of China (English)

    周玉森; 方朝晖; 李新杰; 武玮; 孔艳华; 张允

    2016-01-01

    OBJECTIVE To study the correlation between cystatin C ,retinol‐binding protein and pulmonary infection of patients with diabetes mellitus ,in order to provide evidence for the diagnosis and treatment of diabetes mellitus complicated with pulmonary infection .METHODS A total of 50 patients with diabetes mellitus complicated with pulmonary infection in hospital from Sep .2013 to Sep .2015 were selected as the group A ,and another 50 patients in the same period with diabetes mellitus were selected as the group B ,another 50 patients with pulmonary infec‐tion as the group C .Then the clinical indexes in three groups were compared and the relation to diabetes mellitus complicated with pulmonary infection were analyzed .RESULTS The serum cystatin C ,serum and urine retinol‐binding protein levels of group A were respectively (2 .75 ± 0 .42)mg/L ,(80 .33 ± 6 .74)mg/L and (0 .31 ± 0 .06) mg/L ,and they were all higher than those of group B and group C .The detection results of group A and group B with different glycosylated hemoglobin levels ,group A and group C with different infection degree of pulmonary in‐fection both had significant differences(P<0 .05) .The logistic analysis showed that those serum and urine indexes all had close relationship to the diabetes mellitus complicated with pulmonary infection (P<0 .05) .CONCLUSION The cystatin C and retinol‐binding protein both have close relationship to the diabetes mellitus complicated with pulmonary infection ,so it has active clinical detection value for the disease .%目的:研究胱抑素C、视黄醇结合蛋白与糖尿病患者肺部感染的关系,为糖尿病患者肺部感染的诊断与治疗提供参考依据。方法选取2013年9月-2015年9月医院收治的50例糖尿病并发肺部感染患者为A组,选取同期的50例糖尿病无肺部感染患者为B组,50例单纯肺部感染患者为C组,比较3组患者临床指标,分析与糖尿病并发肺部感染的关系。结果 A

  6. Discussion on the clinical diagnostic value of joint detection with serum cystatin c (cysc) and retinol binding protein (RBP)in nephropathy%探讨血清视黄醇结合蛋白和胱抑素C在肾脏疾病中的诊断价值

    Institute of Scientific and Technical Information of China (English)

    傅园园; 罗厚龙; 农妍; 刘行超

    2016-01-01

    Objective Discussion on the clinical diagnostic value of joint detection with serum cystatin C (cysC)and retinol bind‐ing protin(RBP)in nephropathy .Methods CysC and RBP were detected in 173 nephropathy patinents and 50 controls with Beck‐man auto chemistry analyzer .Urea Cr and UA were detected at the same time with related statistical analysis .Results ⑴RBP level was significantly higher in 173 nephropathy patients than the healthy controls [(70 .86 ± 14 .41)mg/L and(41 .36 ± 5 .68)mg/L re‐spectively ,P<0 .05] .CysC level was significantly higher in 173 nephropathy patients than the healthy controls [(3 .41 ± 0 .65)mg/L and(0 .98 ± 0 .20)mg/L respectively ,P<0 .05] .(2)The positivity rate of CysC was highest ,followed by RBP .And the positivity rate of joint detection serum CysC and RBP was higher ,significantly higher than that of the traditional renal function indexes (inclu‐ding Urea ,Cr ,UA) .Conclusion Either RBP or CysC can be used as a sensitive index for diagnosis of renal disease .The combined detection of RBP and CysC can be more helpful for the diagnostic yield .%目的:探讨血清视黄醇结合蛋白(retinol blinding protein ,RBP)和胱抑素C(Cystatin C ,CysC)联合检测在肾脏疾病中的临床诊断价值。方法采用Beckman‐Coulter全自动生化仪分别检测173例肾病患者和50例健康体检者的血清尿素氮(U‐rea)、肌酐(Cr)、尿酸(UA)、视黄醇结合蛋白(RBP)、胱抑素C(CysC)的含量,并进行相关的统计学分析。结果173例肾病患者的RBP浓度为(70.86±14.41)mg/L ,CysC浓度为(3.41 ± 0.65)mg/L ,对照组RBP浓度为(41.36±5.68)mg/L ,CysC浓度为(0.98 ± 0.20)mg/L ,肾病组明显高于对照组(P<0.05)。各疾病组 Cysc的检出阳性率最高,RBP次之,二者联合检测阳性率更高,明显高于传统肾功能指标Urea、Cr、UA。结论血清视黄醇结合蛋白和胱抑素C

  7. Retinoid-binding proteins: similar protein architectures bind similar ligands via completely different ways.

    Directory of Open Access Journals (Sweden)

    Yu-Ru Zhang

    Full Text Available BACKGROUND: Retinoids are a class of compounds that are chemically related to vitamin A, which is an essential nutrient that plays a key role in vision, cell growth and differentiation. In vivo, retinoids must bind with specific proteins to perform their necessary functions. Plasma retinol-binding protein (RBP and epididymal retinoic acid binding protein (ERABP carry retinoids in bodily fluids, while cellular retinol-binding proteins (CRBPs and cellular retinoic acid-binding proteins (CRABPs carry retinoids within cells. Interestingly, although all of these transport proteins possess similar structures, the modes of binding for the different retinoid ligands with their carrier proteins are different. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we analyzed the various retinoid transport mechanisms using structure and sequence comparisons, binding site analyses and molecular dynamics simulations. Our results show that in the same family of proteins and subcellular location, the orientation of a retinoid molecule within a binding protein is same, whereas when different families of proteins are considered, the orientation of the bound retinoid is completely different. In addition, none of the amino acid residues involved in ligand binding is conserved between the transport proteins. However, for each specific binding protein, the amino acids involved in the ligand binding are conserved. The results of this study allow us to propose a possible transport model for retinoids. CONCLUSIONS/SIGNIFICANCE: Our results reveal the differences in the binding modes between the different retinoid-binding proteins.

  8. Sponging of Cellular Proteins by Viral RNAs

    OpenAIRE

    Charley, Phillida A.; Wilusz, Jeffrey

    2014-01-01

    Viral RNAs accumulate to high levels during infection and interact with a variety of cellular factors including miRNAs and RNA-binding proteins. Although many of these interactions exist to directly modulate replication, translation and decay of viral transcripts, evidence is emerging that abundant viral RNAs may in certain cases serve as a sponge to sequester host non coding RNAs and proteins. By effectively reducing the ability of cellular RNA binding proteins to regulate host cell gene exp...

  9. Differentiation-dependent expression of retinoid-binding proteins in BFC-1 beta adipocytes.

    Science.gov (United States)

    Zovich, D C; Orologa, A; Okuno, M; Kong, L W; Talmage, D A; Piantedosi, R; Goodman, D S; Blaner, W S

    1992-07-15

    Recently, we demonstrated that adipose tissue plays an important role in retinol storage and retinol-binding protein (RBP) synthesis. Our data suggested that RBP expression in adipose tissue is dependent on the state of adipocyte differentiation. To examine this possibility, we explored the differentiation-dependent expression of RBP using BFC-1 beta preadipocytes, which can be stimulated to undergo adipose differentiation. Total RNA was isolated from undifferentiated (preadipocytes) and differentiated (adipocytes) BFC-1 beta cells and analyzed by Northern blotting. RBP mRNA was not detected in the preadipocytes, but considerable RBP mRNA was present in differentiated BFC-1 beta cells. In BFC-1 beta cells, induced to differentiate with insulin and thyroid hormone, RBP mRNA was first detected after 4 days, reached a maximum level by day 10, and remained at this maximum level for at least 2 more days. Cellular retinol-binding protein was expressed at low levels in the BFC-1 beta preadipocytes and the level of expression increased for 6 days after induction to differentiate and slowly declined on later days. Neither the maximum level of RBP expression nor the day on which this level was reached was influenced by the level of retinol provided in the BFC-1 beta culture medium. BFC-1 beta cells secreted newly synthesized RBP into the culture medium at a rate of 43 +/- 14 ng RBP/24 h/10(6) adipocytes. When the BFC-1 beta adipocytes were provided 1.0 microM retinol in the medium, they accumulated the retinol and synthesized retinyl esters. These studies with BFC-1 beta cells confirm that RBP synthesis and secretion and retinol accumulation are intrinsic properties of differentiated adipocytes. Furthermore, they suggest that RBP and cellular retinol-binding protein gene expression are regulated as part of a package of genes which are modulated during adipocyte differentiation.

  10. Cellular regulation by protein phosphorylation.

    Science.gov (United States)

    Fischer, Edmond H

    2013-01-11

    A historical account of the discovery of reversible protein phosphorylation is presented. This process was uncovered in the mid 1950s in a study undertaken with Edwin G. Krebs to elucidate the complex hormonal regulation of skeletal muscle glycogen phosphorylase. Contrary to the known activation of this enzyme by AMP which serves as an allosteric effector, its hormonal regulation results from a phosphorylation of the protein by phosphorylase kinase following the activation of the latter by Ca(2+) and ATP. The study led to the establishment of the first hormonal cascade of successive enzymatic reactions, kinases acting on kinases, initiated by cAMP discovered by Earl Sutherland. It also showed how two different physiological processes, carbohydrate metabolism and muscle contraction, could be regulated in concert.

  11. Protein S-palmitoylation in cellular differentiation

    Science.gov (United States)

    Zhang, Mingzi M.

    2017-01-01

    Reversible protein S-palmitoylation confers spatiotemporal control of protein function by modulating protein stability, trafficking and activity, as well as protein–protein and membrane–protein associations. Enabled by technological advances, global studies revealed S-palmitoylation to be an important and pervasive posttranslational modification in eukaryotes with the potential to coordinate diverse biological processes as cells transition from one state to another. Here, we review the strategies and tools to analyze in vivo protein palmitoylation and interrogate the functions of the enzymes that put on and take off palmitate from proteins. We also highlight palmitoyl proteins and palmitoylation-related enzymes that are associated with cellular differentiation and/or tissue development in yeasts, protozoa, mammals, plants and other model eukaryotes. PMID:28202682

  12. HIV and schistosomiasis in rural Zimbabwe: the association of Retinol-binding protein with disease progression, inflammation and mortality

    Directory of Open Access Journals (Sweden)

    Sebastian Ranzi Kotzé

    2015-04-01

    Conclusions: In HIV-infected individuals, RBP was negatively associated with levels of inflammatory markers, markers of HIV progression, infection with schistosomiasis and markers of schistosomal intensity.

  13. WD40 proteins propel cellular networks.

    Science.gov (United States)

    Stirnimann, Christian U; Petsalaki, Evangelia; Russell, Robert B; Müller, Christoph W

    2010-10-01

    Recent findings indicate that WD40 domains play central roles in biological processes by acting as hubs in cellular networks; however, they have been studied less intensely than other common domains, such as the kinase, PDZ or SH3 domains. As suggested by various interactome studies, they are among the most promiscuous interactors. Structural studies suggest that this property stems from their ability, as scaffolds, to interact with diverse proteins, peptides or nucleic acids using multiple surfaces or modes of interaction. A general scaffolding role is supported by the fact that no WD40 domain has been found with intrinsic enzymatic activity despite often being part of large molecular machines. We discuss the WD40 domain distributions in protein networks and structures of WD40-containing assemblies to demonstrate their versatility in mediating critical cellular functions.

  14. CORRELATION OF RETINOL-BINDING PROTEIN 4 AND RETINOL BINDING TYPE 2 DIA-BETIC NEPHROPATHY%2型糖尿病肾病与视黄醇结合蛋白4的相关性研究

    Institute of Scientific and Technical Information of China (English)

    龚新华; 胡远明; 刘培忠; 黄月玲; 王治伟

    2014-01-01

    目的:探讨视黄醇结合蛋白4对于2型糖尿病肾病的临床检测意义。方法随机选择2013年11月~2014年3月来医院诊治的2型糖尿病合并肾病患者68例为研究组,同时随机抽取同期体检健康者68例为对照A组,随机抽取68例2型糖尿病无肾病者为对照B组。测量研究组与对照组的体质指数、血尿视黄醇结合蛋白4以及胰岛素水平。结果研究组的视黄醇结合蛋白4高于对照组,而且视黄醇结合蛋白4与患者体质指数、胰岛素水平呈现相关性。结论视黄醇结合蛋白4检测对于糖尿病肾病早期检测具有重要的意义,可以为早期糖尿病肾病的诊断提供参考依据。%Objective To explore the clinical significance of RBP 4 for type 2 diabetic nephropathy.Methods Ran-domly selected 68 cases of Type 2 diabetic nephropathy that visited our hospital between November 2013 and February 2014 were selected as research group;68 cases that received health examination during the same period were selected as control group A; and 68 cases of Type 2 diabetes without kidney disease were selected as control group B.BMI, RBP 4 and fasting insulin level were measured and compared in different groups.Results The level of BP4 in research group was higher than that in the control group, and BMI and fasting insulin level in research group were associated with the level of BP4.Conclu-sion RBP4 could be used for assistant diagnosis of type 2 diabetic nephropathy , and it has clinical significance for early de-tection of diabetic nephropathy.

  15. Tuning the Electronic Absorption of Protein-Embedded All-trans-Retinal

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wenjing [Michigan State Univ., East Lansing, MI (United States); Nossoni, Zahra [Michigan State Univ., East Lansing, MI (United States); Berbasova, Tetyana [Michigan State Univ., East Lansing, MI (United States); Watson, Camille T. [Michigan State Univ., East Lansing, MI (United States); Yapici, Ipek [Michigan State Univ., East Lansing, MI (United States); Lee, Kin Sing Stephen [Michigan State Univ., East Lansing, MI (United States); Vasileiou, Chrysoula [Michigan State Univ., East Lansing, MI (United States); Geiger, James H. [Michigan State Univ., East Lansing, MI (United States); Borhan, Babak [Michigan State Univ., East Lansing, MI (United States)

    2014-10-02

    Protein-chromophore interactions are a central component of a wide variety of critical biological processes such as color vision and photosynthesis. To understand the fundamental elements that contribute to spectral tuning of a chromophore inside the protein cavity, we redesigned human cellular retinol binding protein II (hCRBPII) to fully encapsulate all-trans-retinal and form a covalent bond as a protonated Schiff base. The system, using rational mutagenesis designed to alter the electrostatic environment within the binding pocket of the host protein, enabled regulation of the absorption maximum of the pigment in the range of 425 to 644 nanometers. Moreover, with only nine point mutations, the hCRBPII mutants induced a systematic shift in the absorption profile of all-trans-retinal of more than 200 nanometers across the visible spectrum.

  16. Recovery of protein from urine specimens collected in cotton wool.

    Science.gov (United States)

    Smith, G C; Taylor, C M

    1992-01-01

    Cotton wool balls have been used to aid the collection of urine from infants. Concentrations of two urinary proteins, albumin and retinol binding protein, decreased by 40 and 80% respectively within 15 minutes of contact with the cotton wool. Cotton wool balls should not be used when investigating proteinuria. PMID:1489230

  17. Fluorescopic evaluation of protein-lipid relations in cellular signalling.

    NARCIS (Netherlands)

    Pap, E.H.W.

    1994-01-01

    IntroductionCellular communication is partly mediated through the modulation of protein activity, structure and dynamics by lipids. In contrast to the biochemical aspects of lipid signalling, relatively little is known about the physical properties of the "signal" lipids (lipids involved in cellular

  18. Cellular Reprogramming Employing Recombinant Sox2 Protein

    Directory of Open Access Journals (Sweden)

    Marc Thier

    2012-01-01

    Full Text Available Induced pluripotent stem (iPS cells represent an attractive option for the derivation of patient-specific pluripotent cells for cell replacement therapies as well as disease modeling. To become clinically meaningful, safe iPS cells need to be generated exhibiting no permanent genetic modifications that are caused by viral integrations of the reprogramming transgenes. Recently, various experimental strategies have been applied to accomplish transgene-free derivation of iPS cells, including the use of nonintegrating viruses, episomal expression, or excision of transgenes after reprogramming by site-specific recombinases or transposases. A straightforward approach to induce reprogramming factors is the direct delivery of either synthetic mRNA or biologically active proteins. We previously reported the generation of cell-permeant versions of Oct4 (Oct4-TAT and Sox2 (Sox2-TAT proteins and showed that Oct4-TAT is reprogramming-competent, that is, it can substitute for Oct4-encoding virus. Here, we explore conditions for enhanced Sox2-TAT protein stabilization and functional delivery into somatic cells. We show that cell-permeant Sox2 protein can be stabilized by lipid-rich albumin supplements in serum replacement or low-serum-supplemented media. Employing optimized conditions for protein delivery, we demonstrate that Sox2-TAT protein is able to substitute for viral Sox2. Sox2-piPS cells express pluripotency-associated markers and differentiate into all three germ layers.

  19. In vivo cellular imaging using fluorescent proteins - Methods and Protocols

    Directory of Open Access Journals (Sweden)

    M. Monti

    2012-12-01

    Full Text Available The discovery and genetic engineering of fluorescent proteins has revolutionized cell biology. What was previously invisible to the cell often can be made visible with the use of fluorescent proteins. With this words, Robert M. Hoffman introduces In vivo Cellular Imaging Using Fluorescent proteins, the eighteen chapters book dedicated to the description of how fluorescence proteins have changed the way to analyze cellular processes in vivo. Modern researches aim to study new and less invasive methods able to follow the behavior of different cell types in different biological contexts: for example, how cancer cells migrate or how they respond to different therapies. Also, in vivo systems can help researchers to better understand animal embryonic development so as how fluorescence proteins may be used to monitor different processes in living organisms at the molecular and cellular level.

  20. Piezo proteins: regulators of mechanosensation and other cellular processes.

    Science.gov (United States)

    Bagriantsev, Sviatoslav N; Gracheva, Elena O; Gallagher, Patrick G

    2014-11-14

    Piezo proteins have recently been identified as ion channels mediating mechanosensory transduction in mammalian cells. Characterization of these channels has yielded important insights into mechanisms of somatosensation, as well as other mechano-associated biologic processes such as sensing of shear stress, particularly in the vasculature, and regulation of urine flow and bladder distention. Other roles for Piezo proteins have emerged, some unexpected, including participation in cellular development, volume regulation, cellular migration, proliferation, and elongation. Mutations in human Piezo proteins have been associated with a variety of disorders including hereditary xerocytosis and several syndromes with muscular contracture as a prominent feature.

  1. Cellular strategies for regulating functional and nonfunctional protein aggregation.

    Science.gov (United States)

    Gsponer, Jörg; Babu, M Madan

    2012-11-29

    Growing evidence suggests that aggregation-prone proteins are both harmful and functional for a cell. How do cellular systems balance the detrimental and beneficial effect of protein aggregation? We reveal that aggregation-prone proteins are subject to differential transcriptional, translational, and degradation control compared to nonaggregation-prone proteins, which leads to their decreased synthesis, low abundance, and high turnover. Genetic modulators that enhance the aggregation phenotype are enriched in genes that influence expression homeostasis. Moreover, genes encoding aggregation-prone proteins are more likely to be harmful when overexpressed. The trends are evolutionarily conserved and suggest a strategy whereby cellular mechanisms specifically modulate the availability of aggregation-prone proteins to (1) keep concentrations below the critical ones required for aggregation and (2) shift the equilibrium between the monomeric and oligomeric/aggregate form, as explained by Le Chatelier's principle. This strategy may prevent formation of undesirable aggregates and keep functional assemblies/aggregates under control.

  2. Novel intracellular proteins associated with cellular vitamin D action.

    Science.gov (United States)

    Angelo, Giana; Wood, Richard J; Mayer, Jean

    2002-07-01

    Work with vitamin D-resistant New World primates has revealed novel cellular proteins involved in vitamin D action. An "intracellular vitamin D-binding protein" functions to bind vitamin D metabolites in the cell and enhances vitamin D action. By contrast, a "vitamin D response element-binding protein" inhibits vitamin D receptor binding to the DNA and is responsible for vitamin D resistance in New World primates.

  3. Nipah virus matrix protein: expert hacker of cellular machines.

    Science.gov (United States)

    Watkinson, Ruth E; Lee, Benhur

    2016-08-01

    Nipah virus (NiV, Henipavirus) is a highly lethal emergent zoonotic paramyxovirus responsible for repeated human outbreaks of encephalitis in South East Asia. There are no approved vaccines or treatments, thus improved understanding of NiV biology is imperative. NiV matrix protein recruits a plethora of cellular machinery to scaffold and coordinate virion budding. Intriguingly, matrix also hijacks cellular trafficking and ubiquitination pathways to facilitate transient nuclear localization. While the biological significance of matrix nuclear localization for an otherwise cytoplasmic virus remains enigmatic, the molecular details have begun to be characterized, and are conserved among matrix proteins from divergent paramyxoviruses. Matrix protein appropriation of cellular machinery will be discussed in terms of its early nuclear targeting and later role in virion assembly.

  4. Megalin binds and mediates cellular internalization of folate binding protein

    DEFF Research Database (Denmark)

    Birn, Henrik; Zhai, Xiaoyue; Holm, Jan;

    2005-01-01

    Folate is an essential vitamin involved in a number of biological processes. High affinity folate binding proteins (FBPs) exist both as glycosylphosphatidylinositol-linked, membrane associated folate binding proteins and as soluble FBPs in plasma and some secretory fluids such as milk, saliva...... to bind and mediate cellular uptake of FBP. Surface plasmon resonance analysis shows binding of bovine and human milk FBP to immobilized megalin, but not to low density lipoprotein receptor related protein. Binding of (125)I-labeled folate binding protein (FBP) to sections of kidney proximal tubule, known...

  5. Interactions of the HSV-1 UL25 Capsid Protein with Cellular Microtubule-associated Protein

    Institute of Scientific and Technical Information of China (English)

    Lei GUO; Ying ZHANG; Yan-chun CHE; Wen-juan WU; Wei-zhong LI; Li-chun WANG; Yun LIAO; Long-ding LIU; Qi-han LI

    2008-01-01

    An interaction between the HSV-1 UL25 capsid protein and cellular microtubule-associated protein was found using a yeast two-hybrid screen and β-D-galactosidase activity assays. Immunofluorescence microscopy of the UL25 protein demonstrated its co-localization with cellular microtubule-associated protein in the plasma membrane. Further investigations with deletion mutants suggest that UL25 is likely to have a function in the nucleus.

  6. Retinol Binding Protein-4 Is Associated with TNF-α and Not Insulin Resistance in Subjects with Type 2 Diabetes Mellitus and Coronary Heart Disease

    Directory of Open Access Journals (Sweden)

    Nasser M. Al-Daghri

    2009-01-01

    Full Text Available We studied the association between RBP4 and various markers related to insulin resistance and diabetic complications as well as inflammatory markers in Saudi population suffering from type 2 diabetes and coronary heart disease. Patients with type 2 diabetes were divided into 3 groups according to the type of treatment and involvement of coronary artery disease. Serum RBP4, TNF-α, insulin, CRP, resistin, leptin and adiponectin were analysed in all samples. RBP4 levels increased significantly in the group of diabetic subjects treated with oral hypoglycemic agents and diabetic patients with coronary heart disease (30.2 ± 11.8; 33.4 ± 13.6 respectively, while there was no significant change in the other group for diabetic subjects on low-carbohydrate diet (25.1 ± 10.9 compared to control group (22.6 ± 9.5. RPB4 levels were positively correlated with TNF-α in the group of diabetic subjects on oral hypoglycemic agents and diabetic patients with coronary heart disease (r = 0.52, P < 0.05; r = 0.58, P < 0.05 respectively. No correlations were found between RBP4 levels and insulin resistance in all studied groups. Our findings suggest that serum RBP4 levels is associated with pro-inflammatory cytokine (TNF-α and is not associated with insulin resistance among patients with type 2 diabetes and coronary heart disease.

  7. Serum Retinol-Binding Protein 4 Concentration and Its Ratio to Serum Retinol Are Associated with Obesity and Metabolic Syndrome Components in Children

    NARCIS (Netherlands)

    Aeberli, I.; Molinari, L.; Spinas, G.; Lehmann, R.; Allemand, l' D.; Zimmermann, M.B.

    2007-01-01

    Objective: The objective of the study was to measure serum RBP4, serum retinol (SR), the RBP4-to-SR molar ratio, and dietary VA intakes in normal-weight and overweight children and investigate the relationship of these variables to IR, subclinical inflammation, and the metabolic syndrome in this age

  8. Identification of a novel Rev-interacting cellular protein

    Directory of Open Access Journals (Sweden)

    Werner Thomas

    2005-04-01

    Full Text Available Abstract Background Human cell types respond differently to infection by human immunodeficiency virus (HIV. Defining specific interactions between host cells and viral proteins is essential in understanding how viruses exploit cellular functions and the innate strategies underlying cellular control of HIV replication. The HIV Rev protein is a post-transcriptional inducer of HIV gene expression and an important target for interaction with cellular proteins. Identification of Rev-modulating cellular factors may eventually contribute to the design of novel antiviral therapies. Results Yeast-two hybrid screening of a T-cell cDNA library with Rev as bait led to isolation of a novel human cDNA product (16.4.1. 16.4.1-containing fusion proteins showed predominant cytoplasmic localization, which was dependent on CRM1-mediated export from the nucleus. Nuclear export activity of 16.4.1 was mapped to a 60 amino acid region and a novel transport signal identified. Interaction of 16.4.1 with Rev in human cells was shown in a mammalian two-hybrid assay and by colocalization of Rev and 16.4.1 in nucleoli, indicating that Rev can recruit 16.4.1 to the nucleus/nucleoli. Rev-dependent reporter expression was inhibited by overexpressing 16.4.1 and stimulated by siRNAs targeted to 16.4.1 sequences, demonstrating that 16.4.1 expression influences the transactivation function of Rev. Conclusion These results suggest that 16.4.1 may act as a modulator of Rev activity. The experimental strategies outlined in this study are applicable to the identification and biological characterization of further novel Rev-interacting cellular factors.

  9. Cellular reprogramming through mitogen-activated protein kinases

    Directory of Open Access Journals (Sweden)

    Justin eLee

    2015-10-01

    Full Text Available Mitogen-activated protein kinase (MAPK cascades are conserved eukaryote signaling modules where MAPKs, as the final kinases in the cascade, phosphorylate protein substrates to regulate cellular processes. While some progress in the identification of MAPK substrates has been made in plants, the knowledge on the spectrum of substrates and their mechanistic action is still fragmentary. In this focused review, we discuss the biological implications of the data in our original paper (Sustained mitogen-activated protein kinase activation reprograms defense metabolism and phosphoprotein profile in Arabidopsis thaliana; Frontiers in Plant Science 5: 554 in the context of related research. In our work, we mimicked in vivo activation of two stress-activated MAPKs, MPK3 and MPK6, through transgenic manipulation of Arabidopsis thaliana and used phosphoproteomics analysis to identify potential novel MAPK substrates. Here, we plotted the identified putative MAPK substrates (and downstream phosphoproteins as a global protein clustering network. Based on a highly stringent selection confidence level, the core networks highlighted a MAPK-induced cellular reprogramming at multiple levels of gene and protein expression – including transcriptional, post-transcriptional, translational, post-translational (such as protein modification, folding and degradation steps, and also protein re-compartmentalization. Additionally, the increase in putative substrates/phosphoproteins of energy metabolism and various secondary metabolite biosynthesis pathways coincides with the observed accumulation of defense antimicrobial substances as detected by metabolome analysis. Furthermore, detection of protein networks in phospholipid or redox elements suggests activation of downstream signaling events. Taken in context with other studies, MAPKs are key regulators that reprogram cellular events to orchestrate defense signaling in eukaryotes.

  10. A receptor for infectious and cellular prion protein

    Directory of Open Access Journals (Sweden)

    V.R. Martins

    1999-07-01

    Full Text Available Prions are an unconventional form of infectious agents composed only of protein and involved in transmissible spongiform encephalopathies in humans and animals. The infectious particle is composed by PrPsc which is an isoform of a normal cellular glycosyl-phosphatidylinositol (GPI anchored protein, PrPc, of unknown function. The two proteins differ only in conformation, PrPc is composed of 40% a helix while PrPsc has 60% ß-sheet and 20% a helix structure. The infection mechanism is trigged by interaction of PrPsc with cellular prion protein causing conversion of the latter's conformation. Therefore, the infection spreads because new PrPsc molecules are generated exponentially from the normal PrPc. The accumulation of insoluble PrPsc is probably one of the events that lead to neuronal death. Conflicting data in the literature showed that PrPc internalization is mediated either by clathrin-coated pits or by caveolae-like membranous domains. However, both pathways seem to require a third protein (a receptor or a prion-binding protein either to make the connection between the GPI-anchored molecule to clathrin or to convert PrPc into PrPsc. We have recently characterized a 66-kDa membrane receptor which binds PrPc in vitro and in vivo and mediates the neurotoxicity of a human prion peptide. Therefore, the receptor should have a role in the pathogenesis of prion-related diseases and in the normal cellular process. Further work is necessary to clarify the events triggered by the association of PrPc/PrPsc with the receptor.

  11. Cellular recycling of proteins in seed dormancy alleviation and germination

    Directory of Open Access Journals (Sweden)

    Krystyna Oracz

    2016-07-01

    Full Text Available Each step of the seed-to-seed cycle of plant development including seed germination is characterized by a specific set of proteins. The continual renewal and/or replacement of these biomolecules are crucial for optimal plant adaptation. As proteins are the main effectors inside the cells, their levels need to be tightly regulated. This is partially achieved by specific proteolytic pathways via multicatalytic protease complexes defined as 20S and 26S proteasomes. In plants, the 20S proteasome is responsible for degradation of carbonylated proteins, while the 26S being a part of ubiquitin-proteasome pathway (UPP is known to be involved in proteolysis of phytohormone signaling regulators. On the other hand, the role of translational control of plant development is also well documented, especially in the context of pollen tube growth and light signaling. Despite the current progress that has been made in seed biology, the sequence of cellular events that determine if the seed can germinate or not are still far from complete understanding. The role and mechanisms of regulation of proteome composition during processes occurring in the plant’s photosynthetic tissues have been well characterized since many years, but in nonphotosynthetic seeds it has emerged as a tempting research task only since the last decade. This review discusses the recent discoveries providing insights into the role of protein turnover in seed dormancy alleviation, and germination, with a focus on the control of translation and proteasomal proteolysis. The presented novel data of translatome profiling in seeds highlighted that post-transcriptional regulation of germination results from a timely regulated initiation of translation. In addition, the importance of 26S proteasome in the degradation of regulatory elements of cellular signaling and that of the 20S complex in proteolysis of specific carbonylated proteins in hormonal- and light-dependent processes occurring in seeds is

  12. Fluorescence microscopy of single autofluorescent proteins for cellular biology

    CERN Document Server

    Cognet, Laurent; Choquet, Daniel; Lounis, Brahim

    2002-01-01

    In this paper we review the applicability of autofluorescent proteins for single-molecule imaging in biology. The photophysical characteristics of several mutants of the Green Fluorescent Protein (GFP) and those of DsRed are compared and critically discussed for their use in cellular biology. The alternative use of two-photon excitation at the single-molecule level or Fluorescence Correlation Spectroscopy is envisaged for the study of individual autofluorescent proteins. Single-molecule experiments performed in live cells using eGFP and preferably eYFP fusion proteins are reviewed. Finally, the first use at the single-molecule level of citrine, a more photostable variant of the eYFP is reported when fused to a receptor for neurotransmitter in live cells.

  13. Protein carbonylation and metal-catalyzed protein oxidation in a cellular perspective

    DEFF Research Database (Denmark)

    Møller, Ian Max; Rogowska-Wrzesinska, Adelina; Rao, R S P

    2011-01-01

    Proteins can become oxidatively modified in many different ways, either by direct oxidation of amino acid side chains and protein backbone or indirectly by conjugation with oxidation products of polyunsaturated fatty acids and carbohydrates. While reversible oxidative modifications are thought...... to be relevant in physiological processes, irreversible oxidative modifications are known to contribute to cellular damage and disease. The most well-studied irreversible protein oxidation is carbonylation. In this work we first examine how protein carbonylation occurs via metal-catalyzed oxidation (MCO) in vivo...... and in vitro with an emphasis on cellular metal ion homeostasis and metal binding. We then review proteomic methods currently used for identifying carbonylated proteins and their sites of modification. Finally, we discuss the identified carbonylated proteins and the pattern of carbonylation sites in relation...

  14. Efficient cellular solid-state NMR of membrane proteins by targeted protein labeling

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Lindsay A. [University of Oxford, Oxford Particle Imaging Centre, The Wellcome Trust Centre for Human Genetics, Division of Structural Biology, Nuffield Department of Medicine (United Kingdom); Daniëls, Mark; Cruijsen, Elwin A. W. van der; Folkers, Gert E.; Baldus, Marc, E-mail: m.baldus@uu.nl [Utrecht University, NMR Spectroscopy, Department of Chemistry, Faculty of Science, Bijvoet Center for Biomolecular Research (Netherlands)

    2015-06-15

    Solid-state NMR spectroscopy (ssNMR) has made significant progress towards the study of membrane proteins in their native cellular membranes. However, reduced spectroscopic sensitivity and high background signal levels can complicate these experiments. Here, we describe a method for ssNMR to specifically label a single protein by repressing endogenous protein expression with rifampicin. Our results demonstrate that treatment of E. coli with rifampicin during induction of recombinant membrane protein expression reduces background signals for different expression levels and improves sensitivity in cellular membrane samples. Further, the method reduces the amount of time and resources needed to produce membrane protein samples, enabling new strategies for studying challenging membrane proteins by ssNMR.

  15. PACRG, a protein linked to ciliary motility, mediates cellular signaling.

    Science.gov (United States)

    Loucks, Catrina M; Bialas, Nathan J; Dekkers, Martijn P J; Walker, Denise S; Grundy, Laura J; Li, Chunmei; Inglis, P Nick; Kida, Katarzyna; Schafer, William R; Blacque, Oliver E; Jansen, Gert; Leroux, Michel R

    2016-07-01

    Cilia are microtubule-based organelles that project from nearly all mammalian cell types. Motile cilia generate fluid flow, whereas nonmotile (primary) cilia are required for sensory physiology and modulate various signal transduction pathways. Here we investigate the nonmotile ciliary signaling roles of parkin coregulated gene (PACRG), a protein linked to ciliary motility. PACRG is associated with the protofilament ribbon, a structure believed to dictate the regular arrangement of motility-associated ciliary components. Roles for protofilament ribbon-associated proteins in nonmotile cilia and cellular signaling have not been investigated. We show that PACRG localizes to a small subset of nonmotile cilia in Caenorhabditis elegans, suggesting an evolutionary adaptation for mediating specific sensory/signaling functions. We find that it influences a learning behavior known as gustatory plasticity, in which it is functionally coupled to heterotrimeric G-protein signaling. We also demonstrate that PACRG promotes longevity in C. elegans by acting upstream of the lifespan-promoting FOXO transcription factor DAF-16 and likely upstream of insulin/IGF signaling. Our findings establish previously unrecognized sensory/signaling functions for PACRG and point to a role for this protein in promoting longevity. Furthermore, our work suggests additional ciliary motility-signaling connections, since EFHC1 (EF-hand containing 1), a potential PACRG interaction partner similarly associated with the protofilament ribbon and ciliary motility, also positively regulates lifespan.

  16. Absorption of Vitamin A and Carotenoids by the Enterocyte: Focus on Transport Proteins

    Directory of Open Access Journals (Sweden)

    Emmanuelle Reboul

    2013-09-01

    Full Text Available Vitamin A deficiency is a public health problem in most developing countries, especially in children and pregnant women. It is thus a priority in health policy to improve preformed vitamin A and/or provitamin A carotenoid status in these individuals. A more accurate understanding of the molecular mechanisms of intestinal vitamin A absorption is a key step in this direction. It was long thought that β-carotene (the main provitamin A carotenoid in human diet, and thus all carotenoids, were absorbed by a passive diffusion process, and that preformed vitamin A (retinol absorption occurred via an unidentified energy-dependent transporter. The discovery of proteins able to facilitate carotenoid uptake and secretion by the enterocyte during the past decade has challenged established assumptions, and the elucidation of the mechanisms of retinol intestinal absorption is in progress. After an overview of vitamin A and carotenoid fate during gastro-duodenal digestion, our focus will be directed to the putative or identified proteins participating in the intestinal membrane and cellular transport of vitamin A and carotenoids across the enterocyte (i.e., Scavenger Receptors or Cellular Retinol Binding Proteins, among others. Further progress in the identification of the proteins involved in intestinal transport of vitamin A and carotenoids across the enterocyte is of major importance for optimizing their bioavailability.

  17. Absorption of vitamin A and carotenoids by the enterocyte: focus on transport proteins.

    Science.gov (United States)

    Reboul, Emmanuelle

    2013-09-12

    Vitamin A deficiency is a public health problem in most developing countries, especially in children and pregnant women. It is thus a priority in health policy to improve preformed vitamin A and/or provitamin A carotenoid status in these individuals. A more accurate understanding of the molecular mechanisms of intestinal vitamin A absorption is a key step in this direction. It was long thought that β-carotene (the main provitamin A carotenoid in human diet), and thus all carotenoids, were absorbed by a passive diffusion process, and that preformed vitamin A (retinol) absorption occurred via an unidentified energy-dependent transporter. The discovery of proteins able to facilitate carotenoid uptake and secretion by the enterocyte during the past decade has challenged established assumptions, and the elucidation of the mechanisms of retinol intestinal absorption is in progress. After an overview of vitamin A and carotenoid fate during gastro-duodenal digestion, our focus will be directed to the putative or identified proteins participating in the intestinal membrane and cellular transport of vitamin A and carotenoids across the enterocyte (i.e., Scavenger Receptors or Cellular Retinol Binding Proteins, among others). Further progress in the identification of the proteins involved in intestinal transport of vitamin A and carotenoids across the enterocyte is of major importance for optimizing their bioavailability.

  18. The cellular prion protein: a player in immunological quiescence

    Directory of Open Access Journals (Sweden)

    Maren Kolltveit Bakkebø

    2015-09-01

    Full Text Available Despite intensive studies since the 1990s, the physiological role of the cellular prion protein (PrPC remains elusive. Here, we present a novel concept suggesting that PrPC contributes to immunological quiescence in addition to cell protection. PrPC is highly expressed in diverse organs that by multiple means are particularly protected from inflammation, such as the brain, eye, placenta, pregnant uterus and testes, while at the same time it is expressed in most cells of the lymphoreticular system. In this paradigm, PrPC serves two principal roles: to modulate the inflammatory potential of immune cells and to protect vulnerable parenchymal cells against noxious insults generated through inflammation. Here we review studies of PrPC physiology in view of this concept.

  19. Stimulation of Cellular Proliferation by Hepatitis B Virus X Protein

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    Charles R. Madden

    2001-01-01

    Full Text Available Chronic infection with the hepatitis B virus (HBV is a known risk factor in the development of human hepatocellular carcinoma (HCC. The HBV-encoded X protein, HBx, has been investigated for properties that may explain its cancer cofactor role in transgenic mouse lines. We discuss here recent data showing that HBx is able to induce hepatocellular proliferation in vitro and in vivo. This property of HBx is predicted to sensitize hepatocytes to other HCC cofactors, including exposure to carcinogens and to other hepatitis viruses. Cellular proliferation is intimately linked to the mechanism(s by which most tumor-associated viruses transform virus-infected cells. The HBx alteration of the cell cycle provides an additional mechanism by which chronic HBV infection may contribute to HCC.

  20. Domain-Swapped Dimers of Intracellular Lipid-Binding Proteins: Evidence for Ordered Folding Intermediates.

    Science.gov (United States)

    Assar, Zahra; Nossoni, Zahra; Wang, Wenjing; Santos, Elizabeth M; Kramer, Kevin; McCornack, Colin; Vasileiou, Chrysoula; Borhan, Babak; Geiger, James H

    2016-09-06

    Human Cellular Retinol Binding Protein II (hCRBPII), a member of the intracellular lipid-binding protein family, is a monomeric protein responsible for the intracellular transport of retinol and retinal. Herein we report that hCRBPII forms an extensive domain-swapped dimer during bacterial expression. The domain-swapped region encompasses almost half of the protein. The dimer represents a novel structural architecture with the mouths of the two binding cavities facing each other, producing a new binding cavity that spans the length of the protein complex. Although wild-type hCRBPII forms the dimer, the propensity for dimerization can be substantially increased via mutation at Tyr60. The monomeric form of the wild-type protein represents the thermodynamically more stable species, making the domain-swapped dimer a kinetically trapped entity. Hypothetically, the wild-type protein has evolved to minimize dimerization of the folding intermediate through a critical hydrogen bond (Tyr60-Glu72) that disfavors the dimeric form.

  1. Transient expression and cellular localization of recombinant proteins in cultured insect cells

    Science.gov (United States)

    Heterologous protein expression systems are used for production of recombinant proteins, interpretation of cellular trafficking/localization, and for the determination of biochemical function of proteins at the sub-organismal level. Although baculovirus expression systems are increasingly used for ...

  2. A pipeline for determining protein-protein interactions and proximities in the cellular milieu.

    Science.gov (United States)

    Subbotin, Roman I; Chait, Brian T

    2014-11-01

    It remains extraordinarily challenging to elucidate endogenous protein-protein interactions and proximities within the cellular milieu. The dynamic nature and the large range of affinities of these interactions augment the difficulty of this undertaking. Among the most useful tools for extracting such information are those based on affinity capture of target bait proteins in combination with mass spectrometric readout of the co-isolated species. Although highly enabling, the utility of affinity-based methods is generally limited by difficulties in distinguishing specific from nonspecific interactors, preserving and isolating all unique interactions including those that are weak, transient, or rapidly exchanging, and differentiating proximal interactions from those that are more distal. Here, we have devised and optimized a set of methods to address these challenges. The resulting pipeline involves flash-freezing cells in liquid nitrogen to preserve the cellular environment at the moment of freezing; cryomilling to fracture the frozen cells into intact micron chunks to allow for rapid access of a chemical reagent and to stabilize the intact endogenous subcellular assemblies and interactors upon thawing; and utilizing the high reactivity of glutaraldehyde to achieve sufficiently rapid stabilization at low temperatures to preserve native cellular interactions. In the course of this work, we determined that relatively low molar ratios of glutaraldehyde to reactive amines within the cellular milieu were sufficient to preserve even labile and transient interactions. This mild treatment enables efficient and rapid affinity capture of the protein assemblies of interest under nondenaturing conditions, followed by bottom-up MS to identify and quantify the protein constituents. For convenience, we have termed this approach Stabilized Affinity Capture Mass Spectrometry. Here, we demonstrate that Stabilized Affinity Capture Mass Spectrometry allows us to stabilize and elucidate

  3. Cellular prion protein and NMDA receptor modulation: protecting against excitotoxicity

    Directory of Open Access Journals (Sweden)

    Stefanie A.G. Black

    2014-08-01

    Full Text Available Although it is well established that misfolding of the cellular prion protein (PrPC into the beta-sheet-rich, aggregated scrapie conformation (PrPSc causes a variety of transmissible spongiform encephalopathies (TSEs, the physiological roles of PrPC are still incompletely understood. There is accumulating evidence describing the roles of PrPC in neurodegeneration and neuroinflammation. Recently, we identified a functional regulation of NMDA receptors by PrPC that involves formation of a physical protein complex between these proteins. Excessive NMDA receptor activity during conditions such as ischemia mediates enhanced Ca2+ entry into cells and contributes to excitotoxic neuronal death. In addition, NMDA receptors and/or PrPC play critical roles in neuroinflammation and glial cell toxicity. Inhibition of NMDA receptor activity protects against PrPSc-induced neuronal death. Moreover, in mice lacking PrPC, infarct size is increased after focal cerebral ischemia, and absence of PrPC increases susceptibility of neurons to NMDA receptor-dependent death. Recently, PrPC was found to be a receptor for oligomeric beta-amyloid (Abeta peptides, suggesting a role for PrPC in Alzheimer’s disease. Our recent findings suggest that Abeta peptides enhance NMDA receptor current by perturbing the normal copper- and PrPC-dependent regulation of these receptors. Here, we review evidence highlighting a role for PrPC in preventing NMDA receptor-mediated excitotoxicity and inflammation. There is a need for more detailed molecular characterization of PrPC-mediated regulation of NMDA receptors, such as determining which NMDA receptor subunits mediate pathogenic effects upon loss of PrPC-mediated regulation and identifying PrPC binding site(s on the receptor. This knowledge will allow development of novel therapeutic interventions for not only TSEs, but also for Alzheimer’s disease and other neurodegenerative disorders involving dysfunction of PrPC.

  4. Predict drug-protein interaction in cellular networking.

    Science.gov (United States)

    Xiao, Xuan; Min, Jian-Liang; Wang, Pu; Chou, Kuo-Chen

    2013-01-01

    Involved with many diseases such as cancer, diabetes, neurodegenerative, inflammatory and respiratory disorders, GPCRs (G-protein-coupled receptors) are the most frequent targets for drug development: over 50% of all prescription drugs currently on the market are actually acting by targeting GPCRs directly or indirectly. Found in every living thing and nearly all cells, ion channels play crucial roles for many vital functions in life, such as heartbeat, sensory transduction, and central nervous system response. Their dysfunction may have significant impact to human health, and hence ion channels are deemed as "the next GPCRs". To develop GPCR-targeting or ion-channel-targeting drugs, the first important step is to identify the interactions between potential drug compounds with the two kinds of protein receptors in the cellular networking. In this minireview, we are to introduce two predictors. One is called iGPCR-Drug accessible at http://www.jci-bioinfo.cn/iGPCR-Drug/; the other called iCDI-PseFpt at http://www.jci-bioinfo.cn/iCDI-PseFpt. The former is for identifying the interactions of drug compounds with GPCRs; while the latter for that with ion channels. In both predictors, the drug compound was formulated by the two-dimensional molecular fingerprint, and the protein receptor by the pseudo amino acid composition generated with the grey model theory, while the operation engine was the fuzzy K-nearest neighbor algorithm. For the convenience of most experimental pharmaceutical and medical scientists, a step-bystep guide is provided on how to use each of the two web-servers to get the desired results without the need to follow the complicated mathematics involved originally for their establishment.

  5. Integrated cellular network of transcription regulations and protein-protein interactions

    Directory of Open Access Journals (Sweden)

    Chen Bor-Sen

    2010-03-01

    Full Text Available Abstract Background With the accumulation of increasing omics data, a key goal of systems biology is to construct networks at different cellular levels to investigate cellular machinery of the cell. However, there is currently no satisfactory method to construct an integrated cellular network that combines the gene regulatory network and the signaling regulatory pathway. Results In this study, we integrated different kinds of omics data and developed a systematic method to construct the integrated cellular network based on coupling dynamic models and statistical assessments. The proposed method was applied to S. cerevisiae stress responses, elucidating the stress response mechanism of the yeast. From the resulting integrated cellular network under hyperosmotic stress, the highly connected hubs which are functionally relevant to the stress response were identified. Beyond hyperosmotic stress, the integrated network under heat shock and oxidative stress were also constructed and the crosstalks of these networks were analyzed, specifying the significance of some transcription factors to serve as the decision-making devices at the center of the bow-tie structure and the crucial role for rapid adaptation scheme to respond to stress. In addition, the predictive power of the proposed method was also demonstrated. Conclusions We successfully construct the integrated cellular network which is validated by literature evidences. The integration of transcription regulations and protein-protein interactions gives more insight into the actual biological network and is more predictive than those without integration. The method is shown to be powerful and flexible and can be used under different conditions and for different species. The coupling dynamic models of the whole integrated cellular network are very useful for theoretical analyses and for further experiments in the fields of network biology and synthetic biology.

  6. Dynamic circadian protein-protein interaction networks predict temporal organization of cellular functions.

    Directory of Open Access Journals (Sweden)

    Thomas Wallach

    2013-03-01

    Full Text Available Essentially all biological processes depend on protein-protein interactions (PPIs. Timing of such interactions is crucial for regulatory function. Although circadian (~24-hour clocks constitute fundamental cellular timing mechanisms regulating important physiological processes, PPI dynamics on this timescale are largely unknown. Here, we identified 109 novel PPIs among circadian clock proteins via a yeast-two-hybrid approach. Among them, the interaction of protein phosphatase 1 and CLOCK/BMAL1 was found to result in BMAL1 destabilization. We constructed a dynamic circadian PPI network predicting the PPI timing using circadian expression data. Systematic circadian phenotyping (RNAi and overexpression suggests a crucial role for components involved in dynamic interactions. Systems analysis of a global dynamic network in liver revealed that interacting proteins are expressed at similar times likely to restrict regulatory interactions to specific phases. Moreover, we predict that circadian PPIs dynamically connect many important cellular processes (signal transduction, cell cycle, etc. contributing to temporal organization of cellular physiology in an unprecedented manner.

  7. Insights into the physiological function of cellular prion protein

    Directory of Open Access Journals (Sweden)

    Martins V.R.

    2001-01-01

    Full Text Available Prions have been extensively studied since they represent a new class of infectious agents in which a protein, PrPsc (prion scrapie, appears to be the sole component of the infectious particle. They are responsible for transmissible spongiform encephalopathies, which affect both humans and animals. The mechanism of disease propagation is well understood and involves the interaction of PrPsc with its cellular isoform (PrPc and subsequently abnormal structural conversion of the latter. PrPc is a glycoprotein anchored on the cell surface by a glycosylphosphatidylinositol moiety and expressed in most cell types but mainly in neurons. Prion diseases have been associated with the accumulation of the abnormally folded protein and its neurotoxic effects; however, it is not known if PrPc loss of function is an important component. New efforts are addressing this question and trying to characterize the physiological function of PrPc. At least four different mouse strains in which the PrP gene was ablated were generated and the results regarding their phenotype are controversial. Localization of PrPc on the cell membrane makes it a potential candidate for a ligand uptake, cell adhesion and recognition molecule or a membrane signaling molecule. Recent data have shown a potential role for PrPc in the metabolism of copper and moreover that this metal stimulates PrPc endocytosis. Our group has recently demonstrated that PrPc is a high affinity laminin ligand and that this interaction mediates neuronal cell adhesion and neurite extension and maintenance. Moreover, PrPc-caveolin-1 dependent coupling seems to trigger the tyrosine kinase Fyn activation. These data provide the first evidence for PrPc involvement in signal transduction.

  8. Prion search and cellular prion protein expression in stranded dolphins.

    Science.gov (United States)

    Di Guardo, G; Cocumelli, C; Meoli, R; Barbaro, K; Terracciano, G; Di Francesco, C E; Mazzariol, S; Eleni, C

    2012-01-01

    The recent description of a prion disease (PD) case in a free-ranging bottlenose dolphin (Tursiops truncatus) prompted us to carry out an extensive search for the disease-associated isoform (PrPSc) of the cellular prion protein (PrPC) in the brain and in a range of lymphoid tissues from 23 striped dolphins (Stenella coeruleoalba), 5 bottlenose dolphins and 2 Risso s dolphins (Grampus griseus) found stranded between 2007 and 2012 along the Italian coastline. Three striped dolphins and one bottlenose dolphin showed microscopic lesions of encephalitis, with no evidence of spongiform brain lesions being detected in any of the 30 free-ranging cetaceans investigated herein. Nevertheless, we could still observe a prominent PrPC immunoreactivity in the brain as well as in lymphoid tissues from these dolphins. Although immunohistochemical and Western blot investigations yielded negative results for PrPSc deposition in all tissues from the dolphins under study, the reported occurrence of a spontaneous PD case in a wild dolphin is an intriguing issue and a matter of concern for both prion biology and intra/inter-species transmissibility, as well as for cetacean conservation medicine.

  9. Protein source and choice of anticoagulant decisively affect nanoparticle protein corona and cellular uptake

    Science.gov (United States)

    Schöttler, S.; Klein, Katja; Landfester, K.; Mailänder, V.

    2016-03-01

    Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance of the choice of protein source used for in vitro protein corona analysis is concisely investigated. Major and decisive differences in cellular uptake of a polystyrene nanoparticle incubated in fetal bovine serum, human serum, human citrate and heparin plasma are reported. Furthermore, the protein compositions are determined for coronas formed in the respective incubation media. A strong influence of heparin, which is used as an anticoagulant for plasma generation, on cell interaction is demonstrated. While heparin enhances the uptake into macrophages, it prevents internalization into HeLa cells. Taken together we can give the recommendation that human plasma anticoagulated with citrate seems to give the most relevant results for in vitro studies of nanoparticle uptake.Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance

  10. Ethanol cellular defense induce unfolded protein response in yeast

    Directory of Open Access Journals (Sweden)

    Elisabet eNavarro-Tapia

    2016-02-01

    Full Text Available Ethanol is a valuable industrial product and a common metabolite used by many cell types. However, this molecule produces high levels of cytotoxicity affecting cellular performance at several levels. In the presence of ethanol, cells must adjust some of their components, such as the membrane lipids to maintain homeostasis. In the case of microorganism as Saccharomyces cerevisiae, ethanol is one of the principal products of their metabolism and is the main stress factor during fermentation. Although many efforts have been made, mechanisms of ethanol tolerance are not fully understood and very little evidence is available to date for specific signaling by ethanol in the cell. This work studied two Saccharomyces cerevisiae strains, CECT10094 and Temohaya-MI26, isolated from flor wine and agave fermentation (a traditional fermentation from Mexico respectively, which differ in ethanol tolerance, in order to understand the molecular mechanisms underlying the ethanol stress response and the reasons for different ethanol tolerance. The transcriptome was analyzed after ethanol stress and, among others, an increased activation of genes related with the unfolded protein response (UPR and its transcription factor, Hac1p, was observed in the tolerant strain CECT10094. We observed that this strain also resist more UPR agents than Temohaya-MI26 and the UPR-ethanol stress correlation was corroborated observing growth of 15 more strains and discarding UPR correlation with other stresses as thermal or oxidative stress. Furthermore, higher activation of UPR pathway in the tolerant strain CECT10094 was observed using a UPR mCherry reporter. Finally, we observed UPR activation in response to ethanol stress in other S. cerevisiae ethanol tolerant strains as the wine strains T73 and EC1118. This work demonstrates that the UPR pathway is activated under ethanol stress occurring in a standard fermentation and links this response to an enhanced ethanol tolerance. Thus

  11. Retinol status and expression of retinol-related proteins in methionine-choline deficient rats.

    Science.gov (United States)

    Miyazaki, Hiroshi; Takitani, Kimitaka; Koh, Maki; Inoue, Akiko; Kishi, Kanta; Tamai, Hiroshi

    2014-01-01

    Retinol and its derivative, retinoic acid, have pleiotropic functions including vision, immunity, hematopoiesis, reproduction, cell differentiation/growth, and development. Non-alcoholic fatty liver disease (NAFLD) is one of the most common diseases in developed countries and encompasses a broad spectrum of forms, ranging from steatosis to steatohepatitis, which develops further to cirrhosis. Retinol status has an important role in liver homeostasis. The purpose of this study was to evaluate the retinol status and expression of retinol-related proteins, including enzymes and binding proteins, in methionine-choline deficient (MCD) rats as a model of NAFLD. We examined retinol levels in the plasma and liver and gene expression for β-carotene 15,15'-monooxygenase (BCMO), lecithIn: retinol acyltransferase (LRAT), aldehyde dehydrogenase 1A1 (ALDH1A1), ALDH1A2, and cellular retinol binding protein (CRBP)-I in MCD rats. The plasma retinol levels in MCD rats were lower than those in the controls, whereas hepatic retinol levels in MCD rats were higher. BCMO expression in the intestine and liver in MCD rats was lower, whereas that in the testes and the kidneys was higher than in control rats. Expression of LRAT, CRBP-I, ALDH1A1, and ALDH1A2 in the liver of MCD rats was also higher. Altered expression of retinol-related proteins may affect retinol status in NAFLD.

  12. Cellular Binding of Anionic Nanoparticles is Inhibited by Serum Proteins Independent of Nanoparticle Composition.

    Science.gov (United States)

    Fleischer, Candace C; Kumar, Umesh; Payne, Christine K

    2013-09-01

    Nanoparticles used in biological applications encounter a complex mixture of extracellular proteins. Adsorption of these proteins on the nanoparticle surface results in the formation of a "protein corona," which can dominate the interaction of the nanoparticle with the cellular environment. The goal of this research was to determine how nanoparticle composition and surface modification affect the cellular binding of protein-nanoparticle complexes. We examined the cellular binding of a collection of commonly used anionic nanoparticles: quantum dots, colloidal gold nanoparticles, and low-density lipoprotein particles, in the presence and absence of extracellular proteins. These experiments have the advantage of comparing different nanoparticles under identical conditions. Using a combination of fluorescence and dark field microscopy, flow cytometry, and spectroscopy, we find that cellular binding of these anionic nanoparticles is inhibited by serum proteins independent of nanoparticle composition or surface modification. We expect these results will aid in the design of nanoparticles for in vivo applications.

  13. Methods for the Analysis of Protein Phosphorylation-Mediated Cellular Signaling Networks

    Science.gov (United States)

    White, Forest M.; Wolf-Yadlin, Alejandro

    2016-06-01

    Protein phosphorylation-mediated cellular signaling networks regulate almost all aspects of cell biology, including the responses to cellular stimulation and environmental alterations. These networks are highly complex and comprise hundreds of proteins and potentially thousands of phosphorylation sites. Multiple analytical methods have been developed over the past several decades to identify proteins and protein phosphorylation sites regulating cellular signaling, and to quantify the dynamic response of these sites to different cellular stimulation. Here we provide an overview of these methods, including the fundamental principles governing each method, their relative strengths and weaknesses, and some examples of how each method has been applied to the analysis of complex signaling networks. When applied correctly, each of these techniques can provide insight into the topology, dynamics, and regulation of protein phosphorylation signaling networks.

  14. Cellular prion protein expression is not regulated by the Alzheimer's amyloid precursor protein intracellular domain.

    Directory of Open Access Journals (Sweden)

    Victoria Lewis

    Full Text Available There is increasing evidence of molecular and cellular links between Alzheimer's disease (AD and prion diseases. The cellular prion protein, PrP(C, modulates the post-translational processing of the AD amyloid precursor protein (APP, through its inhibition of the β-secretase BACE1, and oligomers of amyloid-β bind to PrP(C which may mediate amyloid-β neurotoxicity. In addition, the APP intracellular domain (AICD, which acts as a transcriptional regulator, has been reported to control the expression of PrP(C. Through the use of transgenic mice, cell culture models and manipulation of APP expression and processing, this study aimed to clarify the role of AICD in regulating PrP(C. Over-expression of the three major isoforms of human APP (APP(695, APP(751 and APP(770 in cultured neuronal and non-neuronal cells had no effect on the level of endogenous PrP(C. Furthermore, analysis of brain tissue from transgenic mice over-expressing either wild type or familial AD associated mutant human APP revealed unaltered PrP(C levels. Knockdown of endogenous APP expression in cells by siRNA or inhibition of γ-secretase activity also had no effect on PrP(C levels. Overall, we did not detect any significant difference in the expression of PrP(C in any of the cell or animal-based paradigms considered, indicating that the control of cellular PrP(C levels by AICD is not as straightforward as previously suggested.

  15. Clinical significance of serum cystatin C and retinol binding proteinin in patients with primary hypertension nephropathy%原发性高血压肾病患者血清胱抑素C和视黄醇结合蛋白检测的临床意义

    Institute of Scientific and Technical Information of China (English)

    方宗信; 黄瑞茹; 夏昕; 李金南; 李秀义; 汪平

    2013-01-01

    Objective To explore the clinical significance of serum cystatin C (CYSC) and retinol binding proteinin (RBP) in patients with primary hypertension nephropathy. Methods Serum CYSC, RBP and urine micro-protein levels (MALB, IgG, TRFU, α-MG, β2~MG) were detected with immunoturbidimetry in 184 patieents (57 cases in the normal albuminuria group, 59 cases in the microalbuminuria group and 68 cases in the macroalbumin-uria group) with primary hypertension nephropathy, and compared with those of 72 healthy voluntes (the control group). Results The levels of CYSC, RBP, MALB, IgG, TRFU, α1-MG and β-MG in the microalbuminuria group and 68 macroalbuminuria group were significantly higher than those in the control group and the normal albuminuria group (P< 0.05). Serum CYSC had positive correlation with RBP, MALB, IgG, TRFU,a,-MG andβ2-MG 0=0.92, 0.85, 0.76, 0.67, 0.58, 0.63, P<0.05) in the patients. Conclusion The levels of CYSC, RBP, M ALB, IgG, TRFU, a1-MG and β2-MG increase gradually with the primary hypertension nephropathy getting more severe. It could be used as a sensitive marker for early monitoring the development and progress of primary hypertension nephropathy.%目的 探讨原发性高血压肾病患者血清胱抑素C (Cysc)和血清视黄醇结合蛋白(RBP)水平检测的临床意义.方法 应用免疫比浊法对184 例原发性高血压患者(正常蛋白尿组57 例,微量蛋白尿组59 例,大量蛋白尿组68 例)血清Cysc、RBP 以及尿液微量蛋白(MALB、IgG、TRFU、α1-MG、β2-MG)的水平进行检测,并与72 例健康体检者(正常对照组)进行对比分析.结果 微量蛋白尿组和大量蛋白尿组患者血清Cysc、RBP尿MALB、IgG、TRFU、α1-MG、β2-MG 等各项微量蛋白水平显著高于正常对照组和正常蛋白尿组,差异有统计学意义(P<0.05).原发性高血压肾病患者血清Cysc 与血清RBP及各项尿MALB、IgG、TRFU、α1-MG、β2-MG等微量蛋白指标水平呈正相关(r=0.92、0.85、0.76、0

  16. Eukaryotic protein domains as functional units of cellular evolution

    DEFF Research Database (Denmark)

    Jin, Jing; Xie, Xueying; Chen, Chen;

    2009-01-01

    domain compositions and functional properties, termed "domain clubs," which we use to compare multiple eukaryotic proteomes. This analysis shows that different domain types can take distinct evolutionary trajectories, which correlate with the conservation, gain, expansion, or decay of particular...... of different domain types to assess the molecular compartment occupied by each domain. This reveals that specific subsets of domains demarcate particular cellular processes, such as growth factor signaling, chromatin remodeling, apoptotic and inflammatory responses, or vesicular trafficking. We suggest...

  17. Control of Cellular Structural Networks Through Unstructured Protein Domains

    Science.gov (United States)

    2016-07-01

    structural and mechanical networks in cells. The research plan seeks to determine the role of molecular­scale steric forces on the assembly, mechanics...Distribution Unlimited UU UU UU UU 01-07-2016 1-Oct-2009 30-Sep-2015 Final Report: WHITEPAPER; Research Area 8; Control of cellular structural networks ...any other aspect of this collection of information, including suggesstions for reducing this burden, to Washington Headquarters Services , Directorate

  18. An antiviral disulfide compound blocks interaction between arenavirus Z protein and cellular promyelocytic leukemia protein

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, C.C. [Laboratory of Virology, Department of Biological Chemistry, School of Sciences, University of Buenos Aires, 1428 Buenos Aires (Argentina); Topisirovic, I. [Institute de Recherche en Immunologie et en Cancerologie, Universite de Montreal, Montreal, QC, Canada H3T 1J4 (Canada); Djavani, M. [Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, MD 21201 (United States); Borden, K.L.B. [Institute de Recherche en Immunologie et en Cancerologie, Universite de Montreal, Montreal, QC, Canada H3T 1J4 (Canada); Damonte, E.B. [Laboratory of Virology, Department of Biological Chemistry, School of Sciences, University of Buenos Aires, 1428 Buenos Aires (Argentina); Salvato, M.S., E-mail: msalvato@ihv.umaryland.edu [Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, MD 21201 (United States)

    2010-03-19

    The promyelocytic leukemia protein (PML) forms nuclear bodies (NB) that can be redistributed by virus infection. In particular, lymphocytic choriomeningitis virus (LCMV) influences disruption of PML NB through the interaction of PML with the arenaviral Z protein. In a previous report, we have shown that the disulfide compound NSC20625 has antiviral and virucidal properties against arenaviruses, inducing unfolding and oligomerization of Z without affecting cellular RING-containing proteins such as the PML. Here, we further studied the effect of the zinc-finger-reactive disulfide NSC20625 on PML-Z interaction. In HepG2 cells infected with LCMV or transiently transfected with Z protein constructs, treatment with NSC20625 restored PML distribution from a diffuse-cytoplasmic pattern to punctate, discrete NB which appeared identical to NB found in control, uninfected cells. Similar results were obtained in cells transfected with a construct expressing a Z mutant in zinc-binding site 2 of the RING domain, confirming that this Z-PML interaction requires the integrity of only one zinc-binding site. Altogether, these results show that the compound NSC20625 suppressed Z-mediated PML NB disruption and may be used as a tool for designing novel antiviral strategies against arenavirus infection.

  19. Direct protein-protein interactions and substrate channeling between cellular retinoic acid binding proteins and CYP26B1.

    Science.gov (United States)

    Nelson, Cara H; Peng, Chi-Chi; Lutz, Justin D; Yeung, Catherine K; Zelter, Alex; Isoherranen, Nina

    2016-08-01

    Cellular retinoic acid binding proteins (CRABPs) bind all-trans-retinoic acid (atRA) tightly. This study aimed to determine whether atRA is channeled directly to cytochrome P450 (CYP) CYP26B1 by CRABPs, and whether CRABPs interact directly with CYP26B1. atRA bound to CRABPs (holo-CRABP) was efficiently metabolized by CYP26B1. Isotope dilution experiments showed that delivery of atRA to CYP26B1 in solution was similar with or without CRABP. Holo-CRABPs had higher affinity for CYP26B1 than free atRA, but both apo-CRABPs inhibited the formation of 4-OH-RA by CYP26B1. Similar protein-protein interactions between soluble binding proteins and CYPs may be important for other lipophilic CYP substrates.

  20. Physiological enzymology: The next frontier in understanding protein structure and function at the cellular level.

    Science.gov (United States)

    Lee, Irene; Berdis, Anthony J

    2016-01-01

    Historically, the study of proteins has relied heavily on characterizing the activity of a single purified protein isolated from other cellular components. This classic approach allowed scientists to unambiguously define the intrinsic kinetic and chemical properties of that protein. The ultimate hope was to extrapolate this information toward understanding how the enzyme or receptor behaves within its native cellular context. These types of detailed in vitro analyses were necessary to reduce the innate complexities of measuring the singular activity and biochemical properties of a specific enzyme without interference from other enzymes and potential competing substrates. However, recent developments in fields encompassing cell biology, molecular imaging, and chemical biology now provide the unique chemical tools and instrumentation to study protein structure, function, and regulation in their native cellular environment. These advancements provide the foundation for a new field, coined physiological enzymology, which quantifies the function and regulation of enzymes and proteins at the cellular level. In this Special Edition, we explore the area of Physiological Enzymology and Protein Function through a series of review articles that focus on the tools and techniques used to measure the cellular activity of proteins inside living cells. This article is part of a Special Issue entitled: Physiological Enzymology and Protein Functions.

  1. Cellular functions of gamma-secretase-related proteins.

    Science.gov (United States)

    Haffner, Christof; Haass, Christian

    2006-01-01

    Amyloid-beta peptide (Abeta) is generated by gamma-secretase, a membrane protein complex with an unusual aspartyl protease activity consisting of the four components presenilin, nicastrin, APH-1 and PEN-2. Presenilin is considered the catalytic subunit of this complex since it represents the prototype of the new family of intramembrane-cleaving GxGD-type aspartyl proteases. Recently, five novel members of this family and a nicastrin-like protein were identified. Whereas one of the GxGD-type proteins was shown to be identical with signal peptide peptidase (SPP), the function of the others, now called SPP-like proteins (SPPLs), is not known. We therefore analyzed SPPL2b and SPPL3 and demonstrated that they localize to different subcellular compartments suggesting nonredundant functions. This was supported by different phenotypes obtained in knockdown studies in zebrafish embryos. In addition, these phenotypes could be phenocopied by ectopic expression of putative active site mutants, providing strong evidence for a proteolytic function of SPPL2b and SPPL3. We also identified and characterized the nicastrin-like protein nicalin which, together with the 130-kDa protein NOMO (Nodal modulator), forms a membrane protein complex different from gamma-secretase. We found that during zebrafish embryogenesis this complex is involved in the patterning of the axial mesendoderm, a process controlled by the Nodal signaling pathway.

  2. The 14-3-3 protein forms a molecular complex with heat shock protein Hsp60 and cellular prion protein.

    Science.gov (United States)

    Satoh, Jun-ichi; Onoue, Hiroyuki; Arima, Kunimasa; Yamamura, Takashi

    2005-10-01

    The 14-3-3 protein family consists of acidic 30-kDa proteins composed of 7 isoforms expressed abundantly in neurons and glial cells of the central nervous system (CNS). The 14-3-3 protein identified in the cerebrospinal fluid provides a surrogate marker for premortem diagnosis of Creutzfeldt-Jakob disease, although an active involvement of 14-3-3 in the pathogenesis of prion diseases remains unknown. By protein overlay and mass spectrometric analysis of protein extract of NTera2-derived differentiated neurons, we identified heat shock protein Hsp60 as a 14-3-3-interacting protein. The 14-3-3zeta and gamma isoforms interacted with Hsp60, suggesting that the interaction is not isoform-specific. Furthermore, the interaction was identified in SK-N-SH neuroblastoma, U-373MG astrocytoma, and HeLa cervical carcinoma cells. The cellular prion protein (PrPC) along with Hsp60 was coimmunoprecipitated with 14-3-3 in the human brain protein extract. By protein overlay, 14-3-3 interacted with both recombinant human Hsp60 and PrPC produced by Escherichia coli, indicating that the molecular interaction is phosphorylation-independent. The 14-3-3-binding domain was located in the N-terminal half (NTF) of Hsp60 spanning amino acid residues 27-287 and the NTF of PrPC spanning amino acid residues 23-137. By immunostaining, the 14-3-3 protein Hsp60 and PrPC were colocalized chiefly in the mitochondria of human neuronal progenitor cells in culture, and were coexpressed most prominently in neurons and reactive astrocytes in the human brain. These observations indicate that the 14-3-3 protein forms a molecular complex with Hsp60 and PrPC in the human CNS under physiological conditions and suggest that this complex might become disintegrated in the pathologic process of prion diseases.

  3. Evolutionarily Conserved and Nonconserved Cellular Localizations and Functions of Human SIRT Proteins

    OpenAIRE

    Michishita, Eriko; Park, Jean Y.; Burneskis, Jenna M.; Barrett, J. Carl; Horikawa, Izumi

    2005-01-01

    Sir2 is a NAD+-dependent protein deacetylase that extends lifespan in yeast and worms. This study examines seven human proteins homologous to Sir2 (SIRT1 through SIRT7) for cellular localization, expression profiles, protein deacetylation activity, and effects on human cell lifespan. We found that: 1) three nuclear SIRT proteins (SIRT1, SIRT6, and SIRT7) show different subnuclear localizations: SIRT6 and SIRT7 are associated with heterochromatic regions and nucleoli, respectively, where yeast...

  4. Evolutionarily conserved and nonconserved cellular localizations and functions of human SIRT proteins.

    Science.gov (United States)

    Michishita, Eriko; Park, Jean Y; Burneskis, Jenna M; Barrett, J Carl; Horikawa, Izumi

    2005-10-01

    Sir2 is a NAD+-dependent protein deacetylase that extends lifespan in yeast and worms. This study examines seven human proteins homologous to Sir2 (SIRT1 through SIRT7) for cellular localization, expression profiles, protein deacetylation activity, and effects on human cell lifespan. We found that: 1) three nuclear SIRT proteins (SIRT1, SIRT6, and SIRT7) show different subnuclear localizations: SIRT6 and SIRT7 are associated with heterochromatic regions and nucleoli, respectively, where yeast Sir2 functions; 2) SIRT3, SIRT4, and SIRT5 are localized in mitochondria, an organelle that links aging and energy metabolism; 3) cellular p53 is a major in vivo substrate of SIRT1 deacetylase, but not the other six SIRT proteins; 4) SIRT1, but not the other two nuclear SIRT proteins, shows an in vitro deacetylase activity on histone H4 and p53 peptides; and 5) overexpression of any one of the seven SIRT proteins does not extend cellular replicative lifespan in normal human fibroblasts or prostate epithelial cells. This study supports the notion that multiple human SIRT proteins have evolutionarily conserved and nonconserved functions at different cellular locations and reveals that the lifespan of normal human cells, in contrast to that of lower eukaryotes, cannot be manipulated by increased expression of a single SIRT protein.

  5. FERM family proteins and their importance in cellular movements and wound healing (review).

    Science.gov (United States)

    Bosanquet, David C; Ye, Lin; Harding, Keith G; Jiang, Wen G

    2014-07-01

    Motility is a requirement for a number of biological processes, including embryonic development, neuronal development, immune responses, cancer progression and wound healing. Specific to wound healing is the migration of endothelial cells, fibroblasts and other key cellular players into the wound space. Aberrations in wound healing can result in either chronic wounds or abnormally healed wounds. The protein 4.1R, ezrin, radixin, moesin (FERM) superfamily consists of over 40 proteins all containing a three lobed N-terminal FERM domain which binds a variety of cell-membrane associated proteins and lipids. The C-terminal ends of these proteins typically contain an actin-binding domain (ABD). These proteins therefore mediate the linkage between the cell membrane and the actin cytoskeleton, and are involved in cellular movements and migration. Certain FERM proteins have been shown to promote cancer metastasis via this very mechanism. Herein we review the effects of a number of FERM proteins on wound healing and cancer. We show how these proteins typically aid wound healing through their effects on increasing cellular migration and movements, but also typically promote metastasis in cancer. We conclude that FERM proteins play important roles in cellular migration, with markedly different outcomes in the context of cancer and wound healing.

  6. Cellular functions of gamma-secretase-related proteins

    OpenAIRE

    Haffner, Christof; Haass, Christian

    2006-01-01

    Amyloid-beta pepticle (A beta) is generated by gamma-secretase, a membrane protein complex with an unusual aspartyl protease activity consisting of the four components presenilin, nicastrin, APH-1 and PEN-2. Presenilin is considered the catalytic subunit of this complex since it represents the prototype of the new family of intramembrane-cleaving GxGD-type aspartyl proteases. Recently, five novel members of this family and a nicastrin-like protein were identified. Whereas one of the GxGD-type...

  7. Reprogramming cellular events by poly(ADP-ribose)-binding proteins

    Science.gov (United States)

    Pic, Émilie; Ethier, Chantal; Dawson, Ted M.; Dawson, Valina L.; Masson, Jean-Yves; Poirier, Guy G.; Gagné, Jean-Philippe

    2013-01-01

    Poly(ADP-ribosyl)ation is a posttranslational modification catalyzed by the poly(ADP-ribose) polymerases (PARPs). These enzymes covalently modify glutamic, aspartic and lysine amino acid side chains of acceptor proteins by the sequential addition of ADP-ribose (ADPr) units. The poly(ADP-ribose) (pADPr) polymers formed alter the physico-chemical characteristics of the substrate with functional consequences on its biological activities. Recently, non-covalent binding to pADPr has emerged as a key mechanism to modulate and coordinate several intracellular pathways including the DNA damage response, protein stability and cell death. In this review, we describe the basis of non-covalent binding to pADPr that has led to the emerging concept of pADPr-responsive signaling pathways. This review emphasizes the structural elements and the modular strategies developed by pADPr-binding proteins to exert a fine-tuned control of a variety of pathways. Poly(ADP-ribosyl)ation reactions are highly regulated processes, both spatially and temporally, for which at least four specialized pADPr-binding modules accommodate different pADPr structures and reprogram protein functions. In this review, we highlight the role of well-characterized and newly discovered pADPr-binding modules in a diverse set of physiological functions. PMID:23268355

  8. Protein tyrosine phosphatase PTPRR isoforms in cellular signaling and trafficking

    NARCIS (Netherlands)

    Dilaver, Gönül

    2005-01-01

    Previous work has revealed the existence of two Protein Tyrosine Phosphatases in mouse, PTPBR7 and PTP-SL, that were in part identical, suggesting that they originated from the same gene, termed Ptprr (1,5,6). In this thesis, I report on the characterization of the various PTPRR isoforms in neuronal

  9. Protein-protein interaction networks identify targets which rescue the MPP+ cellular model of Parkinson’s disease

    Science.gov (United States)

    Keane, Harriet; Ryan, Brent J.; Jackson, Brendan; Whitmore, Alan; Wade-Martins, Richard

    2015-11-01

    Neurodegenerative diseases are complex multifactorial disorders characterised by the interplay of many dysregulated physiological processes. As an exemplar, Parkinson’s disease (PD) involves multiple perturbed cellular functions, including mitochondrial dysfunction and autophagic dysregulation in preferentially-sensitive dopamine neurons, a selective pathophysiology recapitulated in vitro using the neurotoxin MPP+. Here we explore a network science approach for the selection of therapeutic protein targets in the cellular MPP+ model. We hypothesised that analysis of protein-protein interaction networks modelling MPP+ toxicity could identify proteins critical for mediating MPP+ toxicity. Analysis of protein-protein interaction networks constructed to model the interplay of mitochondrial dysfunction and autophagic dysregulation (key aspects of MPP+ toxicity) enabled us to identify four proteins predicted to be key for MPP+ toxicity (P62, GABARAP, GBRL1 and GBRL2). Combined, but not individual, knockdown of these proteins increased cellular susceptibility to MPP+ toxicity. Conversely, combined, but not individual, over-expression of the network targets provided rescue of MPP+ toxicity associated with the formation of autophagosome-like structures. We also found that modulation of two distinct proteins in the protein-protein interaction network was necessary and sufficient to mitigate neurotoxicity. Together, these findings validate our network science approach to multi-target identification in complex neurological diseases.

  10. PACRG, a protein linked to ciliary motility, mediates cellular signaling.

    OpenAIRE

    Loucks, Catrina M.; Bialas, Nathan J.; Dekkers, Martijn; Walker, Denise S.; Grundy, Laura J.; Li, Chunmei; Inglis, P. Nick; Kida, Katarzyna; Schafer, William R; Blacque, Oliver E; Jansen, Gert; Michel R Leroux

    2016-01-01

    Cilia are microtubule-based organelles that project from nearly all mammalian cell types. Motile cilia generate fluid flow, whereas nonmotile (primary) cilia are required for sensory physiology and modulate various signal transduction pathways. Here we investigate the nonmotile ciliary signaling roles of parkin coregulated gene (PACRG), a protein linked to ciliary motility. PACRG is associated with the protofilament ribbon, a structure believed to dictate the regular arrangement of motility-a...

  11. PACRG, a protein linked to ciliary motility, mediates cellular signaling

    OpenAIRE

    Loucks, Catrina M.; Bialas, Nathan J.; Dekkers, Martijn P. J.; Walker, Denise S.; Grundy, Laura J.; Li, Chunmei; Inglis, P. Nick; Kida, Katarzyna; Schafer, William R; Blacque, Oliver E; Jansen, Gert; Michel R Leroux

    2016-01-01

    Cilia are microtubule-based organelles that project from nearly all mammalian cell types. Motile cilia generate fluid flow, whereas nonmotile (primary) cilia are required for sensory physiology and modulate various signal transduction pathways. Here we investigate the nonmotile ciliary signaling roles of parkin coregulated gene (PACRG), a protein linked to ciliary motility. PACRG is associated with the protofilament ribbon, a structure believed to dictate the regular arrangement of motility-a...

  12. Autoantigenic proteins that bind recombinogenic sequences in Epstein-Barr virus and cellular DNA.

    OpenAIRE

    1994-01-01

    We have identified conserved autoantigenic cellular proteins that bind to G-rich sequence motifs in recombinogenic regions of Epstein-Barr virus (EBV) DNA. This binding activity, called TRBP, recognizes the EBV terminal repeats, a locus responsible for interconversion of linear and circular EBV DNA. We found that TRBP also binds to EBV DNA sequences involved in deletion of EBNA2, a gene product required for immortalization. We show that TRBP binds sequences present in repetitive cellular DNA,...

  13. Cellular oxido-reductive proteins of Chlamydomonas reinhardtii control the biosynthesis of silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Barwal Indu

    2011-12-01

    Full Text Available Abstract Background Elucidation of molecular mechanism of silver nanoparticles (SNPs biosynthesis is important to control its size, shape and monodispersity. The evaluation of molecular mechanism of biosynthesis of SNPs is of prime importance for the commercialization and methodology development for controlling the shape and size (uniform distribution of SNPs. The unicellular algae Chlamydomonas reinhardtii was exploited as a model system to elucidate the role of cellular proteins in SNPs biosynthesis. Results The C. reinhardtii cell free extract (in vitro and in vivo cells mediated synthesis of silver nanoparticles reveals SNPs of size range 5 ± 1 to 15 ± 2 nm and 5 ± 1 to 35 ± 5 nm respectively. In vivo biosynthesized SNPs were localized in the peripheral cytoplasm and at one side of flagella root, the site of pathway of ATP transport and its synthesis related enzymes. This provides an evidence for the involvement of oxidoreductive proteins in biosynthesis and stabilization of SNPs. Alteration in size distribution and decrease of synthesis rate of SNPs in protein-depleted fractions confirmed the involvement of cellular proteins in SNPs biosynthesis. Spectroscopic and SDS-PAGE analysis indicate the association of various proteins on C. reinhardtii mediated in vivo and in vitro biosynthesized SNPs. We have identified various cellular proteins associated with biosynthesized (in vivo and in vitro SNPs by using MALDI-MS-MS, like ATP synthase, superoxide dismutase, carbonic anhydrase, ferredoxin-NADP+ reductase, histone etc. However, these proteins were not associated on the incubation of pre-synthesized silver nanoparticles in vitro. Conclusion Present study provides the indication of involvement of molecular machinery and various cellular proteins in the biosynthesis of silver nanoparticles. In this report, the study is mainly focused towards understanding the role of diverse cellular protein in the synthesis and capping of silver

  14. Generic framework for mining cellular automata models on protein-folding simulations.

    Science.gov (United States)

    Diaz, N; Tischer, I

    2016-05-13

    Cellular automata model identification is an important way of building simplified simulation models. In this study, we describe a generic architectural framework to ease the development process of new metaheuristic-based algorithms for cellular automata model identification in protein-folding trajectories. Our framework was developed by a methodology based on design patterns that allow an improved experience for new algorithms development. The usefulness of the proposed framework is demonstrated by the implementation of four algorithms, able to obtain extremely precise cellular automata models of the protein-folding process with a protein contact map representation. Dynamic rules obtained by the proposed approach are discussed, and future use for the new tool is outlined.

  15. The Interaction of the Gammaherpesvirus 68 orf73 Protein with Cellular BET Proteins Affects the Activation of Cell Cycle Promoters▿

    Science.gov (United States)

    Ottinger, Matthias; Pliquet, Daniel; Christalla, Thomas; Frank, Ronald; Stewart, James P.; Schulz, Thomas F.

    2009-01-01

    Infection of mice with murine gammaherpesvirus 68 (MHV-68) provides a valuable animal model for gamma-2 herpesvirus (rhadinovirus) infection and pathogenesis. The MHV-68 orf73 protein has been shown to be required for the establishment of viral latency in vivo. This study describes a novel transcriptional activation function of the MHV-68 orf73 protein and identifies the cellular bromodomain containing BET proteins Brd2/RING3, Brd3/ORFX, and BRD4 as interaction partners for the MHV-68 orf73 protein. BET protein members are known to interact with acetylated histones, and Brd2 and Brd4 have been implicated in fundamental cellular processes, including cell cycle regulation and transcriptional regulation. Using MHV-68 orf73 peptide array assays, we identified Brd2 and Brd4 interaction sites in the orf73 protein. Mutation of one binding site led to a loss of the interaction with Brd2/4 but not the retinoblastoma protein Rb, to impaired chromatin association, and to a decreased ability to activate the BET-responsive cyclin D1, D2, and E promoters. The results therefore pinpoint the binding site for Brd2/4 in a rhadinoviral orf73 protein and suggest that the recruitment of a member of the BET protein family allows the MHV-68 orf73 protein to activate the promoters of G1/S cyclins. These findings point to parallels between the transcriptional activator functions of rhadinoviral orf73 proteins and papillomavirus E2 proteins. PMID:19244327

  16. Redox modulation of cellular metabolism through targeted degradation of signaling proteins by the proteasome

    Energy Technology Data Exchange (ETDEWEB)

    Squier, Thomas C.

    2006-02-01

    Under conditions of oxidative stress, the 20S proteasome plays a critical role in maintaining cellular homeostasis through the selective degradation of oxidized and damaged proteins. This adaptive stress response is distinct from ubiquitin-dependent pathways in that oxidized proteins are recognized and degraded in an ATP-independent mechanism, which can involve the molecular chaperone Hsp90. Like the regulatory complexes 19S and 11S REG, Hsp90 tightly associates with the 20S proteasome to mediate the recognition of aberrant proteins for degradation. In the case of the calcium signaling protein calmodulin, proteasomal degradation results from the oxidation of a single surface exposed methionine (i.e., Met145); oxidation of the other eight methionines has a minimal effect on the recognition and degradation of calmodulin by the proteasome. Since cellular concentrations of calmodulin are limiting, the targeted degradation of this critical signaling protein under conditions of oxidative stress will result in the downregulation of cellular metabolism, serving as a feedback regulation to diminish the generation of reactive oxygen species. The targeted degradation of critical signaling proteins, such as calmodulin, can function as sensors of oxidative stress to downregulate global rates of metabolism and enhance cellular survival.

  17. Epigenetic regulation of cellular memory by the Polycomb and Trithorax group proteins.

    Science.gov (United States)

    Ringrose, Leonie; Paro, Renato

    2004-01-01

    During the development of multicellular organisms, cells become different from one another by changing their genetic program in response to transient stimuli. Long after the stimulus is gone, "cellular memory" mechanisms enable cells to remember their chosen fate over many cell divisions. The Polycomb and Trithorax groups of proteins, respectively, work to maintain repressed or active transcription states of developmentally important genes through many rounds of cell division. Here we review current ideas on the protein and DNA components of this transcriptional memory system and how they interact dynamically with each other to orchestrate cellular memory for several hundred genes.

  18. Cellular protein quality control and the evolution of aggregates in spinocerebellar ataxia type 3 (SCA3)

    NARCIS (Netherlands)

    Seidel, K.; Meister, M.; Dugbartey, G. J.; Zijlstra, M. P.; Vinet, J.; Brunt, E. R. P.; van Leeuwen, F. W.; Rueb, U.; Kampinga, H. H.; den Dunnen, W. F. A.

    2012-01-01

    K. Seidel, M. Meister, G. J. Dugbartey, M. P. Zijlstra, J. Vinet, E. R. P. Brunt, F. W. van Leeuwen, U. Rub, H. H. Kampinga and W. F. A. den Dunnen (2012) Neuropathology and Applied Neurobiology38, 548558 Cellular protein quality control and the evolution of aggregates in spinocerebellar ataxia type

  19. Lysine acetylation targets protein complexes and co-regulates major cellular functions

    DEFF Research Database (Denmark)

    Choudhary, Chuna Ram; Kumar, Chanchal; Gnad, Florian;

    2009-01-01

    Lysine acetylation is a reversible posttranslational modification of proteins and plays a key role in regulating gene expression. Technological limitations have so far prevented a global analysis of lysine acetylation's cellular roles. We used high-resolution mass spectrometry to identify 3600...

  20. Adipocyte size and cellular expression of caveolar proteins analyzed by confocal microscopy

    DEFF Research Database (Denmark)

    Hulstrøm, Veronica; Prats Gavalda, Clara; Vinten, Jørgen

    2013-01-01

    Caveolae are abundant in adipocytes and are involved in the regulation of lipid accumulation, which is the main volume determinant of these cells. We have developed and applied a confocal microscopic technique for measuring individual cellular expression of the caveolar proteins cavin-1 and caveo...

  1. Protein turnover and cellular autophagy in growing and growth-inhibited 3T3 cells

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulos, T.; Pfeifer, U. (Univ. of Wuerzburg (West Germany))

    1987-07-01

    The relationship between growth, protein degradation, and cellular autophagy was tested in growing and in growth-inhibited 3T3 cell monolayers. For the biochemical evaluation of DNA and protein metabolism, growth-inhibited 3T3 cell monolayers with high cell density and growing 3T3 cell monolayers with low cell density were labeled simultaneously with ({sup 14}C)thymidine and ({sup 3}H)leucine. The evaluation of the DNA turnover and additional ({sup 3}H)thymidine autoradiography showed that 24 to 5% of 3T3 cells continue to replicate even in the growth-inhibited state, where no accumulation of protein and DNA can be observed. Cell loss, therefore, has to be assumed to compensate for the ongoing cell proliferation. When the data of protein turnover were corrected for cell loss, it was found that the rate constant of protein synthesis in nongrowing monolayers was reduced to half the value found in growing monolayers. Simultaneously, the rate constant of protein degradation in nongrowing monolayers was increased to about 1.5-fold the value of growing monolayers. These data are in agreement with the assumption that cellular autophagy represents a major pathway of regulating protein degradation in 3T3 cells and that the regulation of autophagic protein degradation is of relevance for the transition from a growing to a nongrowing state.

  2. 免疫比浊法测定血清视黄醇结合蛋白方法学评价%Turbidimetric immunoassay for detection of retinol-binding protein in serum

    Institute of Scientific and Technical Information of China (English)

    王宁

    2010-01-01

    目的 对免疫透射比浊法测定血清视黄醇结合蛋白(RBP)进行方法学评价.方法 采用免疫比浊测定法,根据美国临床实验室标准化委员会(NCCLS)相关文件,对该方法进行精密度、线性、准确性等评价及临床初步应用.结果 批内CV%<4.0%,批间CV%<5.0%.抗干扰性强,Hb≤4.0 g/L、胆红素小于或等于420 μmol/L、三酰甘油小于或等于10 mmol/L对测定无影响;与进口试剂对比,Y=1.007 5X+0.002 9,r=0.999 5,两者相关性良好,试剂开瓶稳定性良好.结论 免疫比浊测定血清视黄醇结合蛋白,方法简便、快速、灵敏,结果准确,可用自动分析仪测试,适合临床检验科应用.

  3. Identification of dynamic changes in proteins associated with the cellular cytoskeleton after exposure to okadaic acid

    DEFF Research Database (Denmark)

    Opsahl, Jill A; Ljostveit, Sonja; Solstad, Therese;

    2013-01-01

    wanted to identify these phosphoproteins and searched for them in the cellular lipid rafts, which have been found to contain proteins that regulate cytoskeletal dynamics and cell adhesion. By using stable isotope labeling by amino acids in cell culture cells treated with okadaic acid (400 nM) could...... be combined with control cells before the isolation of lipid rafts. Protein phosphorylation events and translocations induced by okadaic acid were identified by mass spectrometry. Okadaic acid was shown to regulate the phosphorylation status and location of proteins associated with the actin cytoskeleton...

  4. PhosphoregDB: The tissue and sub-cellular distribution of mammalian protein kinases and phosphatases

    Directory of Open Access Journals (Sweden)

    Suzuki Harukazu

    2006-02-01

    Full Text Available Abstract Background Protein kinases and protein phosphatases are the fundamental components of phosphorylation dependent protein regulatory systems. We have created a database for the protein kinase-like and phosphatase-like loci of mouse http://phosphoreg.imb.uq.edu.au that integrates protein sequence, interaction, classification and pathway information with the results of a systematic screen of their sub-cellular localization and tissue specific expression data mined from the GNF tissue atlas of mouse. Results The database lets users query where a specific kinase or phosphatase is expressed at both the tissue and sub-cellular levels. Similarly the interface allows the user to query by tissue, pathway or sub-cellular localization, to reveal which components are co-expressed or co-localized. A review of their expression reveals 30% of these components are detected in all tissues tested while 70% show some level of tissue restriction. Hierarchical clustering of the expression data reveals that expression of these genes can be used to separate the samples into tissues of related lineage, including 3 larger clusters of nervous tissue, developing embryo and cells of the immune system. By overlaying the expression, sub-cellular localization and classification data we examine correlations between class, specificity and tissue restriction and show that tyrosine kinases are more generally expressed in fewer tissues than serine/threonine kinases. Conclusion Together these data demonstrate that cell type specific systems exist to regulate protein phosphorylation and that for accurate modelling and for determination of enzyme substrate relationships the co-location of components needs to be considered.

  5. Searching for cellular partners of hantaviral nonstructural protein NSs: Y2H screening of mouse cDNA library and analysis of cellular interactome.

    Directory of Open Access Journals (Sweden)

    Tuomas Rönnberg

    Full Text Available Hantaviruses (Bunyaviridae are negative-strand RNA viruses with a tripartite genome. The small (S segment encodes the nucleocapsid protein and, in some hantaviruses, also the nonstructural protein (NSs. The aim of this study was to find potential cellular partners for the hantaviral NSs protein. Toward this aim, yeast two-hybrid (Y2H screening of mouse cDNA library was performed followed by a search for potential NSs protein counterparts via analyzing a cellular interactome. The resulting interaction network was shown to form logical, clustered structures. Furthermore, several potential binding partners for the NSs protein, for instance ACBD3, were identified and, to prove the principle, interaction between NSs and ACBD3 proteins was demonstrated biochemically.

  6. Searching for cellular partners of hantaviral nonstructural protein NSs: Y2H screening of mouse cDNA library and analysis of cellular interactome.

    Science.gov (United States)

    Rönnberg, Tuomas; Jääskeläinen, Kirsi; Blot, Guillaume; Parviainen, Ville; Vaheri, Antti; Renkonen, Risto; Bouloy, Michele; Plyusnin, Alexander

    2012-01-01

    Hantaviruses (Bunyaviridae) are negative-strand RNA viruses with a tripartite genome. The small (S) segment encodes the nucleocapsid protein and, in some hantaviruses, also the nonstructural protein (NSs). The aim of this study was to find potential cellular partners for the hantaviral NSs protein. Toward this aim, yeast two-hybrid (Y2H) screening of mouse cDNA library was performed followed by a search for potential NSs protein counterparts via analyzing a cellular interactome. The resulting interaction network was shown to form logical, clustered structures. Furthermore, several potential binding partners for the NSs protein, for instance ACBD3, were identified and, to prove the principle, interaction between NSs and ACBD3 proteins was demonstrated biochemically.

  7. Contaminant loading in remote Arctic lakes affects cellular stress-related proteins expression in feral charr.

    Science.gov (United States)

    Wiseman, Steve; Jorgensen, Even H.; Maule, Alec G.; Vijayan, Mathilakath M.

    2011-01-01

    The remote Arctic lakes on Bjornoya Island, Norway, offer a unique opportunity to study possible affect of lifelong contaminant exposure in wild populations of landlocked Arctic charr (Salvelinus alpinus). This is because Lake Ellasjoen has persistent organic pollutant (POP) levels that are significantly greater than in the nearby Lake Oyangen. We examined whether this differential contaminant loading was reflected in the expression of protein markers of exposure and effect in the native fish. We assessed the expressions of cellular stress markers, including cytochrome P4501A (Cyp1A), heat shock protein 70 (hsp70), and glucocorticoid receptor (GR) in feral charr from the two lakes. The average polychlorinated biphenyl (PCB) load in the charr liver from Ellasjoen was approximately 25-fold higher than in individuals from Oyangen. Liver Cyp1A protein expression was significantly higher in individuals from Ellasjoen compared with Oyangen, confirming differential PCB exposure. There was no significant difference in hsp70 protein expression in charr liver between the two lakes. However, brain hsp70 protein expression was significantly elevated in charr from Ellasjoen compared with Oyangen. Also, liver GR protein expression was significantly higher in the Ellasjoen charr compared with Oyangen charr. Taken together, our results suggest changes to cellular stress-related protein expression as a possible adaptation to chronic-contaminant exposure in feral charr in the Norwegian high-Arctic.

  8. Two outer membrane proteins contribute to cellular fitness in Caulobacter crescentus by preventing intracellular S-layer protein accumulation.

    Science.gov (United States)

    Overton, K Wesley; Park, Dan M; Yung, Mimi C; Dohnalkova, Alice C; Smit, John; Jiao, Yongqin

    2016-09-23

    Surface layers, or S-layers, are two-dimensional protein arrays that form the outermost layer of many bacteria and archaea. They serve several functions including physical protection of the cell from environmental threats. The high abundance of S-layer proteins necessitates a highly efficient export mechanism to transport S-layer protein from the cytoplasm to the cell exterior. Caulobacter crescentus is unique in that it has two homologous, seemingly redundant outer membrane proteins, RsaFa and RsaFb, that, together with other components, form a type I protein translocation pathway for S-layer export. These proteins have homology to E. coli TolC, the outer membrane channel of multidrug efflux pumps. Here we provide evidence that, unlike TolC, RsaFa and RsaFb are not involved in either the maintenance of membrane stability or the active export of antimicrobial compounds. Rather, RsaFa and RsaFb are required to prevent intracellular accumulation and aggregation of the S-layer protein RsaA; deletion of RsaFa and RsaFb led to a general growth defect and lowered cellular fitness. Using Western blotting, transmission electron microscopy, and RNA-seq, we show that loss of both RsaFa and RsaFb led to accumulation of insoluble RsaA in the cytoplasm, which in turn caused upregulation of a number of genes involved in protein mis-folding and degradation pathways. These findings provide new insight into the requirement for RsaFa and RsaFb in cellular fitness and tolerance to antimicrobial agents and further our understanding of the S-layer export mechanism on both the transcriptional and translational levels in C. crescentus IMPORTANCE: Decreased growth rate and reduced cell fitness are common side effects of protein production in overexpression systems. Inclusion bodies typically form inside the cell largely due to lack of sufficient export machinery to transport the overexpressed proteins to the extracellular environment. This phenomenon can conceivably also occur in natural

  9. Molecular design and nanoparticle-mediated intracellular delivery of functional proteins to target cellular pathways

    Science.gov (United States)

    Shah, Dhiral Ashwin

    Intracellular delivery of specific proteins and peptides represents a novel method to influence stem cells for gain-of-function and loss-of-function. Signaling control is vital in stem cells, wherein intricate control of and interplay among critical pathways directs the fate of these cells into either self-renewal or differentiation. The most common route to manipulate cellular function involves the introduction of genetic material such as full-length genes and shRNA into the cell to generate (or prevent formation of) the target protein, and thereby ultimately alter cell function. However, viral-mediated gene delivery may result in relatively slow expression of proteins and prevalence of oncogene insertion into the cell, which can alter cell function in an unpredictable fashion, and non-viral delivery may lead to low efficiency of genetic delivery. For example, the latter case plagues the generation of induced pluripotent stem cells (iPSCs) and hinders their use for in vivo applications. Alternatively, introducing proteins into cells that specifically recognize and influence target proteins, can result in immediate deactivation or activation of key signaling pathways within the cell. In this work, we demonstrate the cellular delivery of functional proteins attached to hydrophobically modified silica (SiNP) nanoparticles to manipulate specifically targeted cell signaling proteins. In the Wnt signaling pathway, we have targeted the phosphorylation activity of glycogen synthase kinase-3beta (GSK-3beta) by designing a chimeric protein and delivering it in neural stem cells. Confocal imaging indicates that the SiNP-chimeric protein conjugates were efficiently delivered to the cytosol of human embryonic kidney cells and rat neural stem cells, presumably via endocytosis. This uptake impacted the Wnt signaling cascade, indicated by the elevation of beta-catenin levels, and increased transcription of Wnt target genes, such as c-MYC. The results presented here suggest that

  10. The involvement of XPC protein in the cisplatin DNA damaging treatment-mediated cellular response

    Institute of Scientific and Technical Information of China (English)

    Gan WANG; Alan DOMBKOWSKI; Lynn CHUANG; Xiao Xin S XU

    2004-01-01

    Recognition of DNA damage is a critical step for DNA damage-mediated cellular response. XPC is an important DNA damage recognition protein involved in nucleotide excision repair (NER). We have studied the XPC protein in cisplatin DNA damaging treatment-mediated cellular response. Comparison of the microarray data from both normal and XPCdefective human fibroblasts identified 861 XPC-responsive genes in the cisplatin treatment (with minimum fold change≥1.5).The cell cycle and cell proliferation-related genes are the most affected genes by the XPC defect in the treatment. Many other cellular function genes, especially the DNA repair and signal transduction-related genes, were also affected by the XPC defect in the treatment. To validate the microarray data, the transcription levels of some microarray-identified genes were also determined by an RT-PCR based real time PCR assay. The real time PCR results are consistent with the microarray data for most of the tested genes, indicating the reliability of the microarray data. To further validate the microarray data, the cisplatin treatment-mediated caspase-3 activation was also determined. The Western blot hybridization results indicate that the XPC defect greatly attenuates the cisplatin treatment-mediated Caspase-3 activation. We elucidated the role of p53 protein in the XPC protein DNA damage recognition-mediated signaling process. The XPC defect reduces the cisplatin treatment-mediated p53 response. These results suggest that the XPC protein plays an important role in the cisplatin treatment-mediated cellular response. It may also suggest a possible mechanism of cancer cell drug resistance.

  11. Cellular immune response of humans to the circumsporozoite protein of Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Mauricio M. Rodrigues

    1991-06-01

    Full Text Available The cellular immune response to the circumsporozoite (CS protein of plasmodium vivax of individuals from malaria-endemic areas of Brazil was studied. We examined the in vitro proliferative response of the peripheral blood mononuclear cells (PBMC of 22 individuals when stimulated with a CS recombinant protein (rPvCS-2 and two other synthetic peptides based on the sequenceof the P. vivax CS protein. Seven of the individuals from malaria-endemic area displayed an antigen specific in vitro proliferative responseto the recombinant protein PvCS-2 and one out of 6, proliferative response to the peptide 308-320. In contrast, none of the individuals displayed a proliferative reponse when stimulated with the D/A peptide which represent some of the repeated units present in this CS protein. Our study, therefore, provides evidence for the presence, withinthe major surface antigen of P. vivax sporozoites, of epitopes capble to induce proliferation of human PBMC.

  12. Efficient isolation and elution of cellular proteins using aptamer-mediated protein precipitation assay.

    Science.gov (United States)

    Kim, Kiseok; Lee, SeungJin; Ryu, Sungho; Han, Dongil

    2014-05-23

    Protein precipitation is one of the most widely used methods for antigen detection and purification in biological research. We developed a reproducible aptamer-mediated magnetic protein precipitation method that is able to efficiently capture, purify and isolate the target proteins. We discovered DNA aptamers having individually high affinity and specificity against human epidermal growth factor receptor (EGFR) and human insulin receptor (INSR). Using aptamers and magnetic beads, we showed it is highly efficient technique to enrich endogenous proteins complex and is applicable to identify physiologically relevant protein-protein interactions with minimized nonspecific binding of proteins. The results presented here indicate that aptamers would be applicable as a useful and cost-effective tool to identify the presence of the particular target protein with their specific protein partners.

  13. A Herpesvirus Protein Selectively Inhibits Cellular mRNA Nuclear Export.

    Science.gov (United States)

    Gong, Danyang; Kim, Yong Hoon; Xiao, Yuchen; Du, Yushen; Xie, Yafang; Lee, Kevin K; Feng, Jun; Farhat, Nisar; Zhao, Dawei; Shu, Sara; Dai, Xinghong; Chanda, Sumit K; Rana, Tariq M; Krogan, Nevan J; Sun, Ren; Wu, Ting-Ting

    2016-11-09

    Nuclear mRNA export is highly regulated to ensure accurate cellular gene expression. Viral inhibition of cellular mRNA export can enhance viral access to the cellular translation machinery and prevent anti-viral protein production but is generally thought to be nonselective. We report that ORF10 of Kaposi's sarcoma-associated herpesvirus (KSHV), a nuclear DNA virus, inhibits mRNA export in a transcript-selective manner to control cellular gene expression. Nuclear export inhibition by ORF10 requires an interaction with an RNA export factor, Rae1. Genome-wide analysis reveals a subset of cellular mRNAs whose nuclear export is blocked by ORF10 with the 3' UTRs of ORF10-targeted transcripts conferring sensitivity to export inhibition. The ORF10-Rae1 interaction is important for the virus to express viral genes and produce infectious virions. These results suggest that a nuclear DNA virus can selectively interfere with RNA export to restrict host gene expression for optimal replication.

  14. A simple yeast-based strategy to identify host cellular processes targeted by bacterial effector proteins.

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    Eran Bosis

    Full Text Available Bacterial effector proteins, which are delivered into the host cell via the type III secretion system, play a key role in the pathogenicity of gram-negative bacteria by modulating various host cellular processes to the benefit of the pathogen. To identify cellular processes targeted by bacterial effectors, we developed a simple strategy that uses an array of yeast deletion strains fitted into a single 96-well plate. The array is unique in that it was optimized computationally such that despite the small number of deletion strains, it covers the majority of genes in the yeast synthetic lethal interaction network. The deletion strains in the array are screened for hypersensitivity to the expression of a bacterial effector of interest. The hypersensitive deletion strains are then analyzed for their synthetic lethal interactions to identify potential targets of the bacterial effector. We describe the identification, using this approach, of a cellular process targeted by the Xanthomonas campestris type III effector XopE2. Interestingly, we discover that XopE2 affects the yeast cell wall and the endoplasmic reticulum stress response. More generally, the use of a single 96-well plate makes the screening process accessible to any laboratory and facilitates the analysis of a large number of bacterial effectors in a short period of time. It therefore provides a promising platform for studying the functions and cellular targets of bacterial effectors and other virulence proteins.

  15. Encapsulated Cellular Implants for Recombinant Protein Delivery and Therapeutic Modulation of the Immune System

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    Aurélien Lathuilière

    2015-05-01

    Full Text Available Ex vivo gene therapy using retrievable encapsulated cellular implants is an effective strategy for the local and/or chronic delivery of therapeutic proteins. In particular, it is considered an innovative approach to modulate the activity of the immune system. Two recently proposed therapeutic schemes using genetically engineered encapsulated cells are discussed here: the chronic administration of monoclonal antibodies for passive immunization against neurodegenerative diseases and the local delivery of a cytokine as an adjuvant for anti-cancer vaccines.

  16. The effect of blood protein adsorption on cellular uptake of anatase TiO2 nanoparticles.

    Science.gov (United States)

    Allouni, Zouhir E; Gjerdet, Nils R; Cimpan, Mihaela R; Høl, Paul J

    2015-01-01

    Protein adsorption onto nanoparticles (NPs) in biological fluids has emerged as an important factor when testing biological responses to NPs, as this may influence both uptake and subsequent toxicity. The aim of the present study was to quantify the adsorption of proteins onto TiO2 NPs and to test the influence on cellular uptake. The surface composition of the particles was characterized by thermal analysis and by X-ray photoelectron spectroscopy. The adsorption of three blood proteins, ie, human serum albumin (HSA), γ-globulins (Glbs), and fibrinogen (Fib), onto three types of anatase NPs of different sizes was quantified for each protein. The concentration of the adsorbed protein was measured by ultraviolet-visible spectrophotometry using the Bradford method. The degree of cellular uptake was quantified by inductivity coupled plasma mass spectroscopy, and visualized by an ultra-high resolution imaging system. The proteins were adsorbed onto all of the anatase NPs. The quantity adsorbed increased with time and was higher for the smaller particles. Fib and Glbs showed the highest affinity to TiO2 NPs, while the lowest was seen for HSA. The adsorption of proteins affected the surface charge and the hydrodynamic diameter of the NPs in cell culture medium. The degree of particle uptake was highest in protein-free medium and in the presence HSA, followed by culture medium supplemented with Glbs, and lowest in the presence of Fib. The results indicate that the uptake of anatase NPs by fibroblasts is influenced by the identity of the adsorbed protein.

  17. Prion protein modulates cellular iron uptake: a novel function with implications for prion disease pathogenesis.

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    Ajay Singh

    Full Text Available Converging evidence leaves little doubt that a change in the conformation of prion protein (PrP(C from a mainly alpha-helical to a beta-sheet rich PrP-scrapie (PrP(Sc form is the main event responsible for prion disease associated neurotoxicity. However, neither the mechanism of toxicity by PrP(Sc, nor the normal function of PrP(C is entirely clear. Recent reports suggest that imbalance of iron homeostasis is a common feature of prion infected cells and mouse models, implicating redox-iron in prion disease pathogenesis. In this report, we provide evidence that PrP(C mediates cellular iron uptake and transport, and mutant PrP forms alter cellular iron levels differentially. Using human neuroblastoma cells as models, we demonstrate that over-expression of PrP(C increases intra-cellular iron relative to non-transfected controls as indicated by an increase in total cellular iron, the cellular labile iron pool (LIP, and iron content of ferritin. As a result, the levels of iron uptake proteins transferrin (Tf and transferrin receptor (TfR are decreased, and expression of iron storage protein ferritin is increased. The positive effect of PrP(C on ferritin iron content is enhanced by stimulating PrP(C endocytosis, and reversed by cross-linking PrP(C on the plasma membrane. Expression of mutant PrP forms lacking the octapeptide-repeats, the membrane anchor, or carrying the pathogenic mutation PrP(102L decreases ferritin iron content significantly relative to PrP(C expressing cells, but the effect on cellular LIP and levels of Tf, TfR, and ferritin is complex, varying with the mutation. Neither PrP(C nor the mutant PrP forms influence the rate or amount of iron released into the medium, suggesting a functional role for PrP(C in cellular iron uptake and transport to ferritin, and dysfunction of PrP(C as a significant contributing factor of brain iron imbalance in prion disorders.

  18. Stem-loop binding protein is a multifaceted cellular regulator of HIV-1 replication

    Science.gov (United States)

    Tucker, Lynne D.; Asara, John M.; Cheruiyot, Collins K.; Lu, Huafei; Wu, Zhijin J.; Newstein, Michael C.; Dooner, Mark S.; Friedman, Jennifer; Lally, Michelle A.; Ramratnam, Bharat

    2016-01-01

    A rare subset of HIV-1–infected individuals is able to maintain plasma viral load (VL) at low levels without antiretroviral treatment. Identifying the mechanisms underlying this atypical response to infection may lead to therapeutic advances for treating HIV-1. Here, we developed a proteomic analysis to compare peripheral blood cell proteomes in 20 HIV-1–infected individuals who maintained either high or low VL with the aim of identifying host factors that impact HIV-1 replication. We determined that the levels of multiple histone proteins were markedly decreased in cohorts of individuals with high VL. This reduction was correlated with lower levels of stem-loop binding protein (SLBP), which is known to control histone metabolism. Depletion of cellular SLBP increased promoter engagement with the chromatin structures of the host gene high mobility group protein A1 (HMGA1) and viral long terminal repeat (LTR), which led to higher levels of HIV-1 genomic integration and proviral transcription. Further, we determined that TNF-α regulates expression of SLBP and observed that plasma TNF-α levels in HIV-1–infected individuals correlated directly with VL levels and inversely with cellular SLBP levels. Our findings identify SLBP as a potentially important cellular regulator of HIV-1, thereby establishing a link between histone metabolism, inflammation, and HIV-1 infection. PMID:27454292

  19. Protein extraction and 2-DE of water- and lipid-soluble proteins from bovine pericardium, a low-cellularity tissue.

    Science.gov (United States)

    Griffiths, Leigh G; Choe, Leila; Lee, Kelvin H; Reardon, Kenneth F; Orton, E Christopher

    2008-11-01

    Bovine pericardium (BP) is an important biomaterial used in the production of glutaraldehyde-fixed heart valves and tissue-engineering applications. The ability to perform proteomic analysis on BP is useful for a range of studies, including investigation of immune rejection after implantation. However, proteomic analysis of fibrous tissues such as BP is challenging due to their relative low-cellularity and abundance of extracellular matrix. A variety of methods for tissue treatment, protein extraction, and fractionation were investigated with the aim of producing high-quality 2-DE gels for both water- and lipid-soluble BP proteins. Extraction of water-soluble proteins with 3-(benzyldimethylammonio)-propanesulfonate followed by n-dodecyl beta-D-maltoside extraction and ethanol precipitation for lipid-soluble proteins provided the best combination of yield, spot number, and resolution on 2-DE gels (Protocol E2). ESI-quadrupole/ion trap or MALDI-TOF/TOF MS protein identifications were performed to confirm bovine origin and appropriate subcellular prefractionation of resolved proteins. Twenty-five unique, predominantly cytoplasmic bovine proteins were identified from the water-soluble fraction. Thirty-two unique, predominantly membrane bovine proteins were identified from the lipid-soluble fraction. These results demonstrated that the final protocol produced high-quality proteomic data from this important tissue for both cytoplasmic and membrane proteins.

  20. Interacting factors and cellular localization of SR protein-specific kinase Dsk1

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    Tang, Zhaohua, E-mail: ztang@jsd.claremont.edu [W.M. Keck Science Center, The Claremont Colleges, Claremont, CA 91711 (United States); Luca, Maria; Taggart-Murphy, Laura; Portillio, Jessica; Chang, Cathey; Guven, Ayse [W.M. Keck Science Center, The Claremont Colleges, Claremont, CA 91711 (United States); Lin, Ren-Jang [Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010 (United States); Murray, Johanne; Carr, Antony [Genome Damage and Stability Center, University of Sussex, Falmer, BN1 9RQ (United Kingdom)

    2012-10-01

    Schizosaccharomyces pombe Dsk1 is an SR protein-specific kinase (SRPK), whose homologs have been identified in every eukaryotic organism examined. Although discovered as a mitotic regulator with protein kinase activity toward SR splicing factors, it remains largely unknown about what and how Dsk1 contributes to cell cycle and pre-mRNA splicing. In this study, we investigated the Dsk1 function by determining interacting factors and cellular localization of the kinase. Consistent with its reported functions, we found that pre-mRNA processing and cell cycle factors are prominent among the proteins co-purified with Dsk1. The identification of these factors led us to find Rsd1 as a novel Dsk1 substrate, as well as the involvement of Dsk1 in cellular distribution of poly(A){sup +} RNA. In agreement with its role in nuclear events, we also found that Dsk1 is mainly localized in the nucleus during G{sub 2} phase and at mitosis. Furthermore, we revealed the oscillation of Dsk1 protein in a cell cycle-dependent manner. This paper marks the first comprehensive analysis of in vivo Dsk1-associated proteins in fission yeast. Our results reflect the conserved role of SRPK family in eukaryotic organisms, and provide information about how Dsk1 functions in pre-mRNA processing and cell-division cycle.

  1. Molecular modeling of the conformational dynamics of the cellular prion protein

    Science.gov (United States)

    Nguyen, Charles; Colling, Ian; Bartz, Jason; Soto, Patricia

    2014-03-01

    Prions are infectious agents responsible for transmissible spongiform encephalopathies (TSEs), a type of fatal neurodegenerative disease in mammals. Prions propagate biological information by conversion of the non-pathological version of the prion protein to the infectious conformation, PrPSc. A wealth of knowledge has shed light on the nature and mechanism of prion protein conversion. In spite of the significance of this problem, we are far from fully understanding the conformational dynamics of the cellular isoform. To remedy this situation we employ multiple biomolecular modeling techniques such as docking and molecular dynamics simulations to map the free energy landscape and determine what specific regions of the prion protein are most conductive to binding. The overall goal is to characterize the conformational dynamics of the cell form of the prion protein, PrPc, to gain insight into inhibition pathways against misfolding. NE EPSCoR FIRST Award to Patricia Soto.

  2. An ectromelia virus profilin homolog interacts with cellular tropomyosin and viral A-type inclusion protein

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    Burke Robert D

    2007-07-01

    Full Text Available Abstract Background Profilins are critical to cytoskeletal dynamics in eukaryotes; however, little is known about their viral counterparts. In this study, a poxviral profilin homolog, ectromelia virus strain Moscow gene 141 (ECTV-PH, was investigated by a variety of experimental and bioinformatics techniques to characterize its interactions with cellular and viral proteins. Results Profilin-like proteins are encoded by all orthopoxviruses sequenced to date, and share over 90% amino acid (aa identity. Sequence comparisons show highest similarity to mammalian type 1 profilins; however, a conserved 3 aa deletion in mammalian type 3 and poxviral profilins suggests that these homologs may be more closely related. Structural analysis shows that ECTV-PH can be successfully modelled onto both the profilin 1 crystal structure and profilin 3 homology model, though few of the surface residues thought to be required for binding actin, poly(L-proline, and PIP2 are conserved. Immunoprecipitation and mass spectrometry identified two proteins that interact with ECTV-PH within infected cells: alpha-tropomyosin, a 38 kDa cellular actin-binding protein, and the 84 kDa product of vaccinia virus strain Western Reserve (VACV-WR 148, which is the truncated VACV counterpart of the orthopoxvirus A-type inclusion (ATI protein. Western and far-western blots demonstrated that the interaction with alpha-tropomyosin is direct, and immunofluorescence experiments suggest that ECTV-PH and alpha-tropomyosin may colocalize to structures that resemble actin tails and cellular protrusions. Sequence comparisons of the poxviral ATI proteins show that although full-length orthologs are only present in cowpox and ectromelia viruses, an ~ 700 aa truncated ATI protein is conserved in over 90% of sequenced orthopoxviruses. Immunofluorescence studies indicate that ECTV-PH localizes to cytoplasmic inclusion bodies formed by both truncated and full-length versions of the viral ATI protein

  3. Functional domains and sub-cellular distribution of the Hedgehog transducing protein Smoothened in Drosophila.

    Science.gov (United States)

    Nakano, Y; Nystedt, S; Shivdasani, A A; Strutt, H; Thomas, C; Ingham, P W

    2004-06-01

    The Hedgehog signalling pathway is deployed repeatedly during normal animal development and its inappropriate activity is associated with various tumours in human. The serpentine protein Smoothened (Smo) is essential for cells to respond to the Hedeghog (Hh) signal; oncogenic forms of Smo have been isolated from human basal cell carcinomas. Despite similarities with ligand binding G-protein coupled receptors, the molecular basis of Smo activity and its regulation remains unclear. In non-responding cells, Smo is suppressed by the activity of another multipass membrane spanning protein Ptc, which acts as the Hh receptor. In Drosophila, binding of Hh to Ptc has been shown to cause an accumulation of phosphorylated Smo protein and a concomitant stabilisation of the activated form of the Ci transcription factor. Here, we identify domains essential for Smo activity and investigate the sub-cellular distribution of the wild type protein in vivo. We find that deletion of the amino terminus and the juxtamembrane region of the carboxy terminus of the protein result in the loss of normal Smo activity. Using Green Fluorescent Protein (GFP) and horseradish peroxidase fusion proteins we show that Smo accumulates in the plasma membrane of cells in which Ptc activity is abrogated by Hh but is targeted to the degradative pathway in cells where Ptc is active. We further demonstrate that Smo accumulation is likely to be a cause, rather than a consequence, of Hh signal transduction.

  4. Topology of Endoplasmic Reticulum-Associated Cellular and Viral Proteins Determined with Split-GFP.

    Science.gov (United States)

    Hyun, Seong-In; Maruri-Avidal, Liliana; Moss, Bernard

    2015-07-01

    The split green fluorescent protein (GFP) system was adapted for investigation of the topology of ER-associated proteins. A 215-amino acid fragment of GFP (S1-10) was expressed in the cytoplasm as a free protein or fused to the N-terminus of calnexin and in the ER as an intraluminal protein or fused to the C-terminus of calnexin. A 16-amino acid fragment of GFP (S11) was fused to the N- or C-terminus of the target protein. Fluorescence occurred when both GFP fragments were in the same intracellular compartment. After validation with the cellular proteins PDI and tapasin, we investigated two vaccinia virus proteins (L2 and A30.5) of unknown topology that localize to the ER and are required for assembly of the viral membrane. Our results indicated that the N- and C-termini of L2 faced the cytoplasmic and luminal sides of the ER, respectively. In contrast both the N- and C-termini of A30.5 faced the cytoplasm. The system offers advantages for quickly determining the topology of intracellular proteins: the S11 tag is similar in length to commonly used epitope tags; multiple options are available for detecting fluorescence in live or fixed cells; transfection protocols are adaptable to numerous expression systems and can enable high throughput applications.

  5. Prevalence of protein calorie malnutrition in general surgical patients.

    Science.gov (United States)

    Tan, Y S; Nambiar, R; Yo, S L

    1992-05-01

    The prevalence of protein calorie malnutrition (PCM) based on ten nutritional parameters was studied in 307 patients undergoing major elective surgical operations. These parameters included anthropometric measurements (weight/height, triceps skin fold thickness, arm muscle circumference) and biochemical (serum total proteins, albumin, transferrin, prealbumin, retinol binding protein) and immunological tests (total lymphocyte count and delayed hypersensitivity test). Using these criteria, the prevalence of PCM was high. Eighty-six percent of patients had at least one abnormal parameter. The prevalence of PCM as judged by weight/height and arm muscle circumference was 49% and 62% respectively. The incidence was higher in cancer than non cancer patients (63% vs 43%). Although serum albumin and total protein levels were normal in 93.5% of patients, acute serum protein markers such as transferrin, prealbumin and retinol binding protein were low in 20-30%. Lymphopenia of 1500 cells/cu mm or less was found in 18% and abnormal delayed hypersensitivity test in 60%. We found that only weight/height, serum protein, transferrin and lymphopenia had predictive values in postoperative morbidity and mortality. By identifying PCM patients early, adequate nutritional support can be given in order to reduce the risk of major surgical complications.

  6. Interactions of the p53 protein family in cellular stress response in gastrointestinal tumors.

    Science.gov (United States)

    Vilgelm, Anna E; Washington, Mary K; Wei, Jinxiong; Chen, Heidi; Prassolov, Vladimir S; Zaika, Alexander I

    2010-03-01

    p53, p63, and p73 are members of the p53 protein family involved in regulation of cell cycle, apoptosis, differentiation, and other critical cellular processes. Here, we investigated the contribution of the entire p53 family in chemotherapeutic drug response in gastrointestinal tumors. Real-time PCR and immunohistochemistry revealed complexity and variability of expression profiles of the p53 protein family. Using colon and esophageal cancer cells, we found that the integral transcription activity of the entire p53 family, as measured by the reporter analysis, associated with response to drug treatment in studied cells. We also found that p53 and p73, as well as p63 and p73, bind simultaneously to the promoters of p53 target genes. Taken together, our results support the view that the p53 protein family functions as an interacting network of proteins and show that cellular responses to chemotherapeutic drug treatment are determined by the total activity of the entire p53 family rather than p53 alone.

  7. Poliovirus infection induces the co-localization of cellular protein SRp20 with TIA-1, a cytoplasmic stress granule protein.

    Science.gov (United States)

    Fitzgerald, Kerry D; Semler, Bert L

    2013-09-01

    Different types of environmental stress cause mammalian cells to form cytoplasmic foci, termed stress granules, which contain mRNPs that are translationally silenced. These foci are transient and dynamic, and contain components of the cellular translation machinery as well as certain mRNAs and RNA binding proteins. Stress granules are known to be induced by conditions such as hypoxia, nutrient deprivation, and oxidative stress, and a number of cellular factors have been identified that are commonly associated with these foci. More recently it was discovered that poliovirus infection also induces the formation of stress granules, although these cytoplasmic foci appear to be somewhat compositionally unique. Work described here examined the punctate pattern of SRp20 (a host cell mRNA splicing protein) localization in the cytoplasm of poliovirus-infected cells, demonstrating the partial co-localization of SRp20 with the stress granule marker protein TIA-1. We determined that SRp20 does not co-localize with TIA-1, however, under conditions of oxidative stress, indicating that the close association of these two proteins during poliovirus infection is not representative of a general response to cellular stress. We confirmed that the expression of a dominant negative version of TIA-1 (TIA-1-PRD) results in the dissociation of stress granules. Finally, we demonstrated that expression of wild type TIA-1 or dominant negative TIA-1-PRD in cells during poliovirus infection does not dramatically affect viral translation. Taken together, these studies provide a new example of the unique cytoplasmic foci that form during poliovirus infection.

  8. Impact of protein pre-coating on the protein corona composition and nanoparticle cellular uptake.

    Science.gov (United States)

    Mirshafiee, Vahid; Kim, Raehyun; Park, Soyun; Mahmoudi, Morteza; Kraft, Mary L

    2016-01-01

    Nanoparticles (NPs) are functionalized with targeting ligands to enable selectively delivering drugs to desired locations in the body. When these functionalized NPs enter the blood stream, plasma proteins bind to their surfaces, forming a protein corona that affects NP uptake and targeting efficiency. To address this problem, new strategies for directing the formation of a protein corona that has targeting capabilities are emerging. Here, we have investigated the feasibility of directing corona composition to promote targeted NP uptake by specific types of cells. We used the well-characterized process of opsonin-induced phagocytosis by macrophages as a simplified model of corona-mediated NP uptake by a desired cell type. We demonstrate that pre-coating silica NPs with gamma-globulins (γ-globulins) produced a protein corona that was enriched with opsonins, such as immunoglobulins. Although immunoglobulins are ligands that bind to receptors on macrophages and elicit phagocytois, the opsonin-rich protein corona did not increase NP uptake by macrophage RAW 264.7 cells. Immunolabeling experiments indicated that the binding of opsonins to their target cell surface receptors was impeded by other proteins in the corona. Thus, corona-mediated NP targeting strategies must optimize both the recruitment of the desired plasma proteins as well as their accessibility and orientation in the corona layer.

  9. Differential activities of cellular and viral macro domain proteins in binding of ADP-ribose metabolites.

    Science.gov (United States)

    Neuvonen, Maarit; Ahola, Tero

    2009-01-01

    Macro domain is a highly conserved protein domain found in both eukaryotes and prokaryotes. Macro domains are also encoded by a set of positive-strand RNA viruses that replicate in the cytoplasm of animal cells, including coronaviruses and alphaviruses. The functions of the macro domain are poorly understood, but it has been suggested to be an ADP-ribose-binding module. We have here characterized three novel human macro domain proteins that were found to reside either in the cytoplasm and nucleus [macro domain protein 2 (MDO2) and ganglioside-induced differentiation-associated protein 2] or in mitochondria [macro domain protein 1 (MDO1)], and compared them with viral macro domains from Semliki Forest virus, hepatitis E virus, and severe acute respiratory syndrome coronavirus, and with a yeast macro protein, Poa1p. MDO2 specifically bound monomeric ADP-ribose with a high affinity (K(d)=0.15 microM), but did not bind poly(ADP-ribose) efficiently. MDO2 also hydrolyzed ADP-ribose-1'' phosphate, resembling Poa1p in all these properties. Ganglioside-induced differentiation-associated protein 2 did not show affinity for ADP-ribose or its derivatives, but instead bound poly(A). MDO1 was generally active in these reactions, including poly(A) binding. Individual point mutations in MDO1 abolished monomeric ADP-ribose binding, but not poly(ADP-ribose) binding; in poly(ADP-ribose) binding assays, the monomer did not compete against polymer binding. The viral macro proteins bound poly(ADP-ribose) and poly(A), but had a low affinity for monomeric ADP-ribose. Thus, the viral proteins do not closely resemble any of the human proteins in their biochemical functions. The differential activity profiles of the human proteins implicate them in different cellular pathways, some of which may involve RNA rather than ADP-ribose derivatives.

  10. Plin2 inhibits cellular glucose uptake through interactions with SNAP23, a SNARE complex protein.

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    Subramanian Senthivinayagam

    Full Text Available Although a link between excess lipid storage and aberrant glucose metabolism has been recognized for many years, little is known what role lipid storage droplets and associated proteins such as Plin2 play in managing cellular glucose levels. To address this issue, the influence of Plin2 on glucose uptake was examined using 2-NBD-Glucose and [(3H]-2-deoxyglucose to show that insulin-mediated glucose uptake was decreased 1.7- and 1.8-fold, respectively in L cell fibroblasts overexpressing Plin2. Conversely, suppression of Plin2 levels by RNAi-mediated knockdown increased 2-NBD-Glucose uptake several fold in transfected L cells and differentiated 3T3-L1 cells. The effect of Plin2 expression on proteins involved in glucose uptake and transport was also examined. Expression of the SNARE protein SNAP23 was increased 1.6-fold while levels of syntaxin-5 were decreased 1.7-fold in Plin2 overexpression cells with no significant changes observed in lipid droplet associated proteins Plin1 or FSP27 or with the insulin receptor, GLUT1, or VAMP4. FRET experiments revealed a close proximity of Plin2 to SNAP23 on lipid droplets to within an intramolecular distance of 51 Å. The extent of targeting of SNAP23 to lipid droplets was determined by co-localization and co-immunoprecipitation experiments to show increased partitioning of SNAP23 to lipid droplets when Plin2 was overexpressed. Taken together, these results suggest that Plin2 inhibits glucose uptake by interacting with, and regulating cellular targeting of SNAP23 to lipid droplets. In summary, the current study for the first time provides direct evidence for the role of Plin2 in mediating cellular glucose uptake.

  11. Identification of Dynamic Changes in Proteins Associated with the Cellular Cytoskeleton after Exposure to Okadaic Acid

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    Peter Roepstorff

    2013-05-01

    Full Text Available Exposure of cells to the diarrhetic shellfish poison, okadaic acid, leads to a dramatic reorganization of cytoskeletal architecture and loss of cell-cell contact. When cells are exposed to high concentrations of okadaic acid (100–500 nM, the morphological rearrangement is followed by apoptotic cell death. Okadaic acid inhibits the broad acting Ser/Thr protein phosphatases 1 and 2A, which results in hyperphosphorylation of a large number of proteins. Some of these hyperphosphorylated proteins are most likely key players in the reorganization of the cell morphology induced by okadaic acid. We wanted to identify these phosphoproteins and searched for them in the cellular lipid rafts, which have been found to contain proteins that regulate cytoskeletal dynamics and cell adhesion. By using stable isotope labeling by amino acids in cell culture cells treated with okadaic acid (400 nM could be combined with control cells before the isolation of lipid rafts. Protein phosphorylation events and translocations induced by okadaic acid were identified by mass spectrometry. Okadaic acid was shown to regulate the phosphorylation status and location of proteins associated with the actin cytoskeleton, microtubules and cell adhesion structures. A large number of these okadaic acid-regulated proteins have previously also been shown to be similarly regulated prior to cell proliferation and migration. Our results suggest that okadaic acid activates general cell signaling pathways that induce breakdown of the cortical actin cytoskeleton and cell detachment.

  12. Exploring Cellular Interactions of Liposomes Using Protein Corona Fingerprints and Physicochemical Properties.

    Science.gov (United States)

    Bigdeli, Arafeh; Palchetti, Sara; Pozzi, Daniela; Hormozi-Nezhad, Mohammad Reza; Baldelli Bombelli, Francesca; Caracciolo, Giulio; Mahmoudi, Morteza

    2016-03-22

    To control liposomes fate and transport upon contact with biofluids, it is essential to consider several parameters affecting the synthetic and biological identity of liposomes, as well as liposome-protein corona (PC) aspects. As a powerful tool in this data mining adventure, quantitative structure-activity relationship (QSAR) approach is used to correlate physicochemical properties of liposomes and their PC fingerprints to multiple quantified biological responses. In the present study, the relationship between cellular interactions of a set of structurally diverse liposomal formulations and their physicochemical and PC properties has been investigated via linear and nonlinear QSAR models. Significant parameters affecting cellular uptake and cell viability of liposomes in two important cancer cell lines (PC3 and HeLa) have been identified. The developed QSARs have the capacity to be implemented in advanced targeted delivery of liposomal drugs.

  13. Divalent metals stabilize cellular prion proteins and alter the rate of proteinase-K dependent limited proteolysis

    Science.gov (United States)

    Background: The key biochemical event in the pathogenesis of prion diseases is the conversion of normal cellular prion proteins (PrP**c) to the proteinase K (PK) resistant, abnormal form (PrP**sc); however, the cellular mechanisms underlying the conversion remain enigmatic. Binding of divalent ca...

  14. Expression and cellular distribution of multidrug resistance-related proteins in the hippocampus of patients with mesial temporal lobe epilepsy

    NARCIS (Netherlands)

    E. Aronica; J.A. Gorter; M. Ramkema; S. Redeker; F. Ozbas-Gercer; E.A. van Vliet; G.L. Scheffer; R.J. Scheper; P. van der Valk; J.C. Baayen; D. Troost

    2004-01-01

    Purpose: This study investigated the cellular distribution of different multidrug resistance (MDR)-related proteins such as P-glycoprotein (P-gp), the multidrug resistance-associated proteins (MRP) 1 and 2, and the major vault protein (MVP) in normal and sclerotic hippocampus of patients with medica

  15. Modification of an acetone-sodium dodecyl sulfate disruption method for cellular protein extraction from neuropathogenic Clostridium botulinum

    Science.gov (United States)

    An acetone-sodium dodecyl sulfate (SDS) disruption method was used for the extraction of cellular proteins from neurotoxigenic Clostridium botulinum. The amount of protein extracted per gram of dry weight and the protein profile as revealed by polyacrylamide gel electrophoresis (PAGE) was comparabl...

  16. Two Outer Membrane Proteins Contribute to Caulobacter crescentus Cellular Fitness by Preventing Intracellular S-Layer Protein Accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Overton, K. Wesley; Park, Dan M.; Yung, Mimi C.; Dohnalkova, Alice C.; Smit, John; Jiao, Yongqin; Parales, R. E.

    2016-09-23

    ABSTRACT

    Surface layers, or S-layers, are two-dimensional protein arrays that form the outermost layer of many bacteria and archaea. They serve several functions, including physical protection of the cell from environmental threats. The high abundance of S-layer proteins necessitates a highly efficient export mechanism to transport the S-layer protein from the cytoplasm to the cell exterior.Caulobacter crescentusis unique in that it has two homologous, seemingly redundant outer membrane proteins, RsaFaand RsaFb, which together with other components form a type I protein translocation pathway for S-layer export. These proteins have homology toEscherichia coliTolC, the outer membrane channel of multidrug efflux pumps. Here we provide evidence that, unlike TolC, RsaFaand RsaFbare not involved in either the maintenance of membrane stability or the active export of antimicrobial compounds. Rather, RsaFaand RsaFbare required to prevent intracellular accumulation and aggregation of the S-layer protein RsaA; deletion of RsaFaand RsaFbled to a general growth defect and lowered cellular fitness. Using Western blotting, transmission electron microscopy, and transcriptome sequencing (RNA-seq), we show that loss of both RsaFaand RsaFbled to accumulation of insoluble RsaA in the cytoplasm, which in turn caused upregulation of a number of genes involved in protein misfolding and degradation pathways. These findings provide new insight into the requirement for RsaFaand RsaFbin cellular fitness and tolerance to antimicrobial agents and further our understanding of the S-layer export mechanism on both the transcriptional and translational levels in

  17. Fast kinase domain-containing protein 3 is a mitochondrial protein essential for cellular respiration

    Energy Technology Data Exchange (ETDEWEB)

    Simarro, Maria [Division of Rheumatology, Immunology and Allergy, Brigham and Women' s Hospital, and Department of Medicine, Harvard Medical School, Boston, MA 02115 (United States); Gimenez-Cassina, Alfredo [Department of Cancer Biology at Dana Farber Institute, Boston, MA 02115 (United States); Kedersha, Nancy [Division of Rheumatology, Immunology and Allergy, Brigham and Women' s Hospital, and Department of Medicine, Harvard Medical School, Boston, MA 02115 (United States); Lazaro, Jean-Bernard; Adelmant, Guillaume O.; Marto, Jarrod A. [Department of Cancer Biology at Dana Farber Institute, Boston, MA 02115 (United States); Rhee, Kirsten [Division of Rheumatology, Immunology and Allergy, Brigham and Women' s Hospital, and Department of Medicine, Harvard Medical School, Boston, MA 02115 (United States); Tisdale, Sarah; Danial, Nika [Department of Cancer Biology at Dana Farber Institute, Boston, MA 02115 (United States); Benarafa, Charaf [Theodor Kocher Institute, University of Bern, 3012 Bern (Switzerland); Orduna, Anonio [Unidad de Investigacion, Hospital Clinico Universitario de Valladolid, 47005 Valladolid (Spain); Anderson, Paul, E-mail: panderson@rics.bwh.harvard.edu [Division of Rheumatology, Immunology and Allergy, Brigham and Women' s Hospital, and Department of Medicine, Harvard Medical School, Boston, MA 02115 (United States)

    2010-10-22

    Research highlights: {yields} Five members of the FAST kinase domain-containing proteins are localized to mitochondria in mammalian cells. {yields} The FASTKD3 interactome includes proteins involved in various aspects of mitochondrial metabolism. {yields} Targeted knockdown of FASTKD3 significantly reduces basal and maximal mitochondrial oxygen consumption. -- Abstract: Fas-activated serine/threonine phosphoprotein (FAST) is the founding member of the FAST kinase domain-containing protein (FASTKD) family that includes FASTKD1-5. FAST is a sensor of mitochondrial stress that modulates protein translation to promote the survival of cells exposed to adverse conditions. Mutations in FASTKD2 have been linked to a mitochondrial encephalomyopathy that is associated with reduced cytochrome c oxidase activity, an essential component of the mitochondrial electron transport chain. We have confirmed the mitochondrial localization of FASTKD2 and shown that all FASTKD family members are found in mitochondria. Although human and mouse FASTKD1-5 genes are expressed ubiquitously, some of them are most abundantly expressed in mitochondria-enriched tissues. We have found that RNA interference-mediated knockdown of FASTKD3 severely blunts basal and stress-induced mitochondrial oxygen consumption without disrupting the assembly of respiratory chain complexes. Tandem affinity purification reveals that FASTKD3 interacts with components of mitochondrial respiratory and translation machineries. Our results introduce FASTKD3 as an essential component of mitochondrial respiration that may modulate energy balance in cells exposed to adverse conditions by functionally coupling mitochondrial protein synthesis to respiration.

  18. A critical role of a cellular membrane traffic protein in poliovirus RNA replication.

    Directory of Open Access Journals (Sweden)

    George A Belov

    2008-11-01

    Full Text Available Replication of many RNA viruses is accompanied by extensive remodeling of intracellular membranes. In poliovirus-infected cells, ER and Golgi stacks disappear, while new clusters of vesicle-like structures form sites for viral RNA synthesis. Virus replication is inhibited by brefeldin A (BFA, implicating some components(s of the cellular secretory pathway in virus growth. Formation of characteristic vesicles induced by expression of viral proteins was not inhibited by BFA, but they were functionally deficient. GBF1, a guanine nucleotide exchange factor for the small cellular GTPases, Arf, is responsible for the sensitivity of virus infection to BFA, and is required for virus replication. Knockdown of GBF1 expression inhibited virus replication, which was rescued by catalytically active protein with an intact N-terminal sequence. We identified a mutation in GBF1 that allows growth of poliovirus in the presence of BFA. Interaction between GBF1 and viral protein 3A determined the outcome of infection in the presence of BFA.

  19. Functions of the cellular prion protein, the end of Moore's law, and Ockham's razor theory.

    Science.gov (United States)

    del Río, José A; Gavín, Rosalina

    2016-01-01

    Since its discovery the cellular prion protein (encoded by the Prnp gene) has been associated with a large number of functions. The proposed functions rank from basic cellular processes such as cell cycle and survival to neural functions such as behavior and neuroprotection, following a pattern similar to that of Moore's law for electronics. In addition, particular interest is increasing in the participation of Prnp in neurodegeneration. However, in recent years a redefinition of these functions has begun, since examples of previously attributed functions were increasingly re-associated with other proteins. Most of these functions are linked to so-called "Prnp-flanking genes" that are close to the genomic locus of Prnp and which are present in the genome of some Prnp mouse models. In addition, their role in neuroprotection against convulsive insults has been confirmed in recent studies. Lastly, in recent years a large number of models indicating the participation of different domains of the protein in apoptosis have been uncovered. However, after more than 10 years of molecular dissection our view is that the simplest mechanistic model in PrP(C)-mediated cell death should be considered, as Ockham's razor theory suggested.

  20. ZRT/IRT-like Protein 14 (ZIP14) Promotes the Cellular Assimilation of Iron from Transferrin*

    OpenAIRE

    Zhao, Ningning; Gao, Junwei; Enns, Caroline A; Knutson, Mitchell D.

    2010-01-01

    ZIP14 is a transmembrane metal ion transporter that is abundantly expressed in the liver, heart, and pancreas. Previous studies of HEK 293 cells and the hepatocyte cell lines AML12 and HepG2 established that ZIP14 mediates the uptake of non-transferrin-bound iron, a form of iron that appears in the plasma during pathologic iron overload. In this study we investigated the role of ZIP14 in the cellular assimilation of iron from transferrin, the circulating plasma protein that normally delivers ...

  1. Multiplex assay for live-cell monitoring of cellular fates of amyloid-β precursor protein (APP.

    Directory of Open Access Journals (Sweden)

    Maria Merezhko

    Full Text Available Amyloid-β precursor protein (APP plays a central role in pathogenesis of Alzheimer's disease. APP has a short half-life and undergoes complex proteolytic processing that is highly responsive to various stimuli such as changes in cellular lipid or energy homeostasis. Cellular trafficking of APP is controlled by its large protein interactome, including dozens of cytosolic adaptor proteins, and also by interactions with lipids. Currently, cellular regulation of APP is mostly studied based on appearance of APP-derived proteolytic fragments to conditioned media and cellular extracts. Here, we have developed a novel live-cell assay system based on several indirect measures that reflect altered APP trafficking and processing in cells. Protein-fragment complementation assay technology for detection of APP-BACE1 protein-protein interaction forms the core of the new assay. In a multiplex form, the assay can measure four endpoints: total cellular APP level, total secreted sAPP level in media, APP-BACE1 interaction in cells and in exosomes released by the cells. Functional validation of the assay with pharmacological and genetic tools revealed distinct patterns of cellular fates of APP, with immediate mechanistic implications. This new technology will facilitate functional genomics studies of late-onset Alzheimer's disease, drug discovery efforts targeting APP and characterization of the physiological functions of APP and its proteolytic fragments.

  2. Anterior gradient protein-2 is a regulator of cellular adhesion in prostate cancer.

    Directory of Open Access Journals (Sweden)

    Diptiman Chanda

    Full Text Available Anterior Gradient Protein (AGR-2 is reported to be over-expressed in many epithelial cancers and promotes metastasis. A clear-cut mechanism for its observed function(s has not been previously identified. We found significant upregulation of AGR-2 expression in a bone metastatic prostate cancer cell line, PC3, following culturing in bone marrow-conditioned medium. Substantial AGR-2 expression was also confirmed in prostate cancer tissue specimens in patients with bone lesions. By developing stable clones of PC3 cells with varying levels of AGR-2 expression, we identified that abrogation of AGR-2 significantly reduced cellular attachment to fibronectin, collagen I, collagen IV, laminin I and fibrinogen. Loss of cellular adhesion was associated with sharp decrease in the expression of α4, α5, αV, β3 and β4 integrins. Failure to undergo apoptosis following detachment is a hallmark of epithelial cancer metastasis. The AGR-2-silenced PC3 cells showed higher resistance to Tumor necrosis factor-related apoptosis- inducing ligand (TRAIL induced apoptosis in vitro. This observation was also supported by significantly reduced Caspase-3 expression in AGR-2-silenced PC3 cells, which is a key effector of both extrinsic and intrinsic death signaling pathways. These data suggest that AGR-2 influence prostate cancer metastasis by regulation of cellular adhesion and apoptosis.

  3. Multiple cellular proteins interact with LEDGF/p75 through a conserved unstructured consensus motif.

    Science.gov (United States)

    Tesina, Petr; Čermáková, Kateřina; Hořejší, Magdalena; Procházková, Kateřina; Fábry, Milan; Sharma, Subhalakshmi; Christ, Frauke; Demeulemeester, Jonas; Debyser, Zeger; De Rijck, Jan; Veverka, Václav; Řezáčová, Pavlína

    2015-08-06

    Lens epithelium-derived growth factor (LEDGF/p75) is an epigenetic reader and attractive therapeutic target involved in HIV integration and the development of mixed lineage leukaemia (MLL1) fusion-driven leukaemia. Besides HIV integrase and the MLL1-menin complex, LEDGF/p75 interacts with various cellular proteins via its integrase binding domain (IBD). Here we present structural characterization of IBD interactions with transcriptional repressor JPO2 and domesticated transposase PogZ, and show that the PogZ interaction is nearly identical to the interaction of LEDGF/p75 with MLL1. The interaction with the IBD is maintained by an intrinsically disordered IBD-binding motif (IBM) common to all known cellular partners of LEDGF/p75. In addition, based on IBM conservation, we identify and validate IWS1 as a novel LEDGF/p75 interaction partner. Our results also reveal how HIV integrase efficiently displaces cellular binding partners from LEDGF/p75. Finally, the similar binding modes of LEDGF/p75 interaction partners represent a new challenge for the development of selective interaction inhibitors.

  4. Rapamycin reverses cellular phenotypes and enhances mutant protein clearance in Hutchinson-Gilford progeria syndrome cells.

    Science.gov (United States)

    Cao, Kan; Graziotto, John J; Blair, Cecilia D; Mazzulli, Joseph R; Erdos, Michael R; Krainc, Dimitri; Collins, Francis S

    2011-06-29

    Hutchinson-Gilford progeria syndrome (HGPS) is a lethal genetic disorder characterized by premature aging. HGPS is most commonly caused by a de novo single-nucleotide substitution in the lamin A/C gene (LMNA) that partially activates a cryptic splice donor site in exon 11, producing an abnormal lamin A protein termed progerin. Accumulation of progerin in dividing cells adversely affects the integrity of the nuclear scaffold and leads to nuclear blebbing in cultured cells. Progerin is also produced in normal cells, increasing in abundance as senescence approaches. Here, we report the effect of rapamycin, a macrolide antibiotic that has been implicated in slowing cellular and organismal aging, on the cellular phenotypes of HGPS fibroblasts. Treatment with rapamycin abolished nuclear blebbing, delayed the onset of cellular senescence, and enhanced the degradation of progerin in HGPS cells. Rapamycin also decreased the formation of insoluble progerin aggregates and induced clearance through autophagic mechanisms in normal fibroblasts. Our findings suggest an additional mechanism for the beneficial effects of rapamycin on longevity and encourage the hypothesis that rapamycin treatment could provide clinical benefit for children with HGPS.

  5. Protein synthesis patterns of Paracoccidiodes brasiliensis isolates in stage-specific forms and during cellular differentiation.

    Science.gov (United States)

    Salem-Izacc, S M; Jesuino, R S; Brito, W A; Pereira, M; Felipe, M S; Soares, C M

    1997-01-01

    In this paper we compared the protein synthesis patterns of Paracoccidioides brasiliensis isolates. The protein profiles were compared for both yeast and mycelial forms and similarity analysis among them was performed by calculating similarity matrices and grouping the isolates in dendrograms. The examined isolates exhibited highly variable cellular morphology at 36 degrees C, when typical yeast cells were expected. On the other hand, at 26 degrees C all the isolates showed mycelial morphology. The analysis of protein synthesis profiles made it possible to cluster the P. brasiliensis isolates into groups that correlated with the morphological data. Interestingly, growth at 36 degrees C strongly decreased the heterogeneity of protein synthesis patterns seen in mycelial isolates. It was possible to cluster the isolates grown at 36 degrees C in three groups based on their two-dimensional protein synthesis analysis. The similarity index observed among the mycelial isolates was lower than that obtained with yeast cells, suggesting a more homogenous gene expression pattern in the host-adapted form than in the saprobic phase.

  6. Cellular and subcellular localization of Ras guanyl nucleotide-releasing protein in the rat hippocampus.

    Science.gov (United States)

    Pierret, P; Vallée, A; Mechawar, N; Dower, N A; Stone, J C; Richardson, P M; Dunn, R J

    2001-01-01

    Ras guanyl nucleotide-releasing protein (RasGRP) is a recently discovered Ras guanyl nucleotide exchange factor that is expressed in selected regions of the rodent CNS, with high levels of expression in the hippocampus. Biochemical studies suggest that RasGRP can activate the Ras signal pathway in response to changes in diacylglycerol and possibly calcium. To investigate potential sites for RasGRP signaling, we have determined the cellular and subcellular localization of RasGRP protein in adult rat hippocampus, and have also examined the appearance of RasGRP mRNA and protein during hippocampal development. RasGRP immunoreactivity is predominately localized to those neurons participating in the direct cortico-hippocampo-cortical loop. In both hippocampal and entorhinal neurons, RasGRP protein appeared to be localized to both dendrites and somata, but not to axons. Electron microscopy of hippocampal pyramidal cells confirmed RasGRP immunoreactivity in neuronal cell bodies and dendrites, where it appeared to be associated with microtubules. The localization of RasGRP to dendrites suggests a role for this pathway in the regulation of dendritic function. Examination of developing hippocampal structures indicated that RasGRP mRNA and protein appear synchronously during the first 2 weeks of postnatal development as these neurons become fully mature. This result indicates that the RasGRP signal transduction pathway is not required during early hippocampal development, but is a feature of mature neurons during the later stages of development.

  7. Redox Modulation of Cellular Signaling and Metabolism Through Reversible Oxidation of Methionine Sensors in Calcium Regulatory Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, Diana J.; Squier, Thomas C.

    2005-01-17

    Adaptive responses associated with environmental stressors are critical to cell survival. These involve the modulation of central signaling protein functions through site-specific and enzymatically reversible oxidative modifications of methionines to coordinate cellular metabolism, energy utilization, and calcium signaling. Under conditions when cellular redox and antioxidant defenses are overwhelmed, the selective oxidation of critical methionines within selected protein sensors functions to down-regulate energy metabolism and the further generation of reactive oxygen species (ROS). Mechanistically, these functional changes within protein sensors take advantage of the helix-breaking character of methionine sulfoxide. Thus, depending on either the ecological niche of the organism or the cellular milieu of different organ systems, cellular metabolism can be fine-tuned to maintain optimal function in the face of variable amounts of collateral oxidative damage. The sensitivity of several calcium regulatory proteins to oxidative modification provides cellular sensors that link oxidative stress to cellular response and recovery. Calmodulin (CaM) is one such critical calcium regulatory protein, which is functionally sensitive to methionine oxidation. Helix destabilization resulting from the oxidation of either Met{sup 144} or Met{sup 145} results in the nonproductive association between CaM and target proteins. The ability of oxidized CaM to stabilize its target proteins in an inhibited state with an affinity similar to that of native (unoxidized) CaM permits this central regulatory protein to function as a cellular rheostat that down-regulates energy metabolism in response to oxidative stress. Likewise, oxidation of a methionine within a critical switch region of the regulatory protein phospholamban is expected to destabilize the phosphorylationdependent helix formation necessary for the release of enzyme inhibition, resulting in a down-regulation of the Ca-ATPase in

  8. Activation of human natural killer cells by the soluble form of cellular prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Yeon-Jae [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Hafis Clinic, Seoul (Korea, Republic of); Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Bum-Chan [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Park, Su-Hyung [Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Young Woo [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Shin, Eui-Cheol, E-mail: ecshin@kaist.ac.kr [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of)

    2015-08-21

    Cellular prion protein (PrP{sup C}) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP{sup C} in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP{sup C} protein on human natural killer (NK) cells. Recombinant soluble PrP{sup C} protein was generated by fusion of human PrP{sup C} with the Fc portion of human IgG{sub 1} (PrP{sup C}-Fc). PrP{sup C}-Fc binds to the surface of human NK cells, particularly to CD56{sup dim} NK cells. PrP{sup C}-Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP{sup C}-Fc facilitated the IL-15-induced proliferation of NK cells. PrP{sup C}-Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP{sup C}-Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP{sup C} (PrP{sup C}-Fc) was generated by fusion of human PrP{sup C} with IgG1 Fc portion. • PrP{sup C}-Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP{sup C}-Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways.

  9. Click chemistry for the conservation of cellular structures and fluorescent proteins: ClickOx.

    Science.gov (United States)

    Löschberger, Anna; Niehörster, Thomas; Sauer, Markus

    2014-05-01

    Reactive oxygen species (ROS), including hydrogen peroxide, are known to cause structural damage not only in living, but also in fixed, cells. Copper-catalyzed azide-alkyne cycloaddition (click chemistry) is known to produce ROS. Therefore, fluorescence imaging of cellular structures, such as the actin cytoskeleton, remains challenging when combined with click chemistry protocols. In addition, the production of ROS substantially weakens the fluorescence signal of fluorescent proteins. This led us to develop ClickOx, which is a new click chemistry protocol for improved conservation of the actin structure and better conservation of the fluorescence signal of green fluorescent protein (GFP)-fusion proteins. Herein we demonstrate that efficient oxygen removal by addition of an enzymatic oxygen scavenger system (ClickOx) considerably reduces ROS-associated damage during labeling of nascent DNA with ATTO 488 azide by Cu(I)-catalyzed click chemistry. Standard confocal and super-resolution fluorescence images of phalloidin-labeled actin filaments and GFP/yellow fluorescent protein-labeled cells verify the conservation of the cytoskeleton microstructure and fluorescence intensity, respectively. Thus, ClickOx can be used advantageously for structure preservation in conventional and most notably in super-resolution microscopy methods.

  10. Diurnal Rhythms Result in Significant Changes in the Cellular Protein Complement in the Cyanobacterium Cyanothece 51142

    Energy Technology Data Exchange (ETDEWEB)

    Stockel, Jana; Jacobs, Jon M.; Elvitigala, Thanura R.; Liberton, Michelle L.; Welsh, Eric A.; Polpitiya, Ashoka D.; Gritsenko, Marina A.; Nicora, Carrie D.; Koppenaal, David W.; Smith, Richard D.; Pakrasi, Himadri B.

    2011-02-22

    Cyanothece sp. ATCC 51142 is a diazotrophic cyanobacterium notable for its ability to perform oxygenic photosynthesis and dinitrogen fixation in the same single cell. Previous transcriptional analysis revealed that the existence of these incompatible cellular processes largely depends on tightly synchronized expression programs involving ,30% of genes in the genome. To expand upon current knowledge, we have utilized sensitive proteomic approaches to examine the impact of diurnal rhythms on the protein complement in Cyanothece 51142. We found that 250 proteins accounting for,5% of the predicted ORFs from the Cyanothece 51142 genome and 20% of proteins detected under alternating light/dark conditions exhibited periodic oscillations in their abundances. Our results suggest that altered enzyme activities at different phases during the diurnal cycle can be attributed to changes in the abundance of related proteins and key compounds. The integration of global proteomics and transcriptomic data further revealed that post-transcriptional events are important for temporal regulation of processes such as photosynthesis in Cyanothece 51142. This analysis is the first comprehensive report on global quantitative proteomics in a unicellular diazotrophic cyanobacterium and uncovers novel findings about diurnal rhythms.

  11. Diurnal Rhythms Result in Significant Changes in the Cellular Protein Complement in the Cyanobacterium Cyanothece 51142

    Science.gov (United States)

    Elvitigala, Thanura R.; Liberton, Michelle; Welsh, Eric A.; Polpitiya, Ashoka D.; Gritsenko, Marina A.; Nicora, Carrie D.; Koppenaal, David W.; Smith, Richard D.; Pakrasi, Himadri B.

    2011-01-01

    Cyanothece sp. ATCC 51142 is a diazotrophic cyanobacterium notable for its ability to perform oxygenic photosynthesis and dinitrogen fixation in the same single cell. Previous transcriptional analysis revealed that the existence of these incompatible cellular processes largely depends on tightly synchronized expression programs involving ∼30% of genes in the genome. To expand upon current knowledge, we have utilized sensitive proteomic approaches to examine the impact of diurnal rhythms on the protein complement in Cyanothece 51142. We found that 250 proteins accounting for ∼5% of the predicted ORFs from the Cyanothece 51142 genome and 20% of proteins detected under alternating light/dark conditions exhibited periodic oscillations in their abundances. Our results suggest that altered enzyme activities at different phases during the diurnal cycle can be attributed to changes in the abundance of related proteins and key compounds. The integration of global proteomics and transcriptomic data further revealed that post-transcriptional events are important for temporal regulation of processes such as photosynthesis in Cyanothece 51142. This analysis is the first comprehensive report on global quantitative proteomics in a unicellular diazotrophic cyanobacterium and uncovers novel findings about diurnal rhythms. PMID:21364985

  12. Diurnal rhythms result in significant changes in the cellular protein complement in the cyanobacterium Cyanothece 51142.

    Directory of Open Access Journals (Sweden)

    Jana Stöckel

    Full Text Available Cyanothece sp. ATCC 51142 is a diazotrophic cyanobacterium notable for its ability to perform oxygenic photosynthesis and dinitrogen fixation in the same single cell. Previous transcriptional analysis revealed that the existence of these incompatible cellular processes largely depends on tightly synchronized expression programs involving ∼30% of genes in the genome. To expand upon current knowledge, we have utilized sensitive proteomic approaches to examine the impact of diurnal rhythms on the protein complement in Cyanothece 51142. We found that 250 proteins accounting for ∼5% of the predicted ORFs from the Cyanothece 51142 genome and 20% of proteins detected under alternating light/dark conditions exhibited periodic oscillations in their abundances. Our results suggest that altered enzyme activities at different phases during the diurnal cycle can be attributed to changes in the abundance of related proteins and key compounds. The integration of global proteomics and transcriptomic data further revealed that post-transcriptional events are important for temporal regulation of processes such as photosynthesis in Cyanothece 51142. This analysis is the first comprehensive report on global quantitative proteomics in a unicellular diazotrophic cyanobacterium and uncovers novel findings about diurnal rhythms.

  13. Diurnal rhythms result in significant changes in the cellular protein complement in the cyanobacterium Cyanothece 51142.

    Science.gov (United States)

    Stöckel, Jana; Jacobs, Jon M; Elvitigala, Thanura R; Liberton, Michelle; Welsh, Eric A; Polpitiya, Ashoka D; Gritsenko, Marina A; Nicora, Carrie D; Koppenaal, David W; Smith, Richard D; Pakrasi, Himadri B

    2011-02-22

    Cyanothece sp. ATCC 51142 is a diazotrophic cyanobacterium notable for its ability to perform oxygenic photosynthesis and dinitrogen fixation in the same single cell. Previous transcriptional analysis revealed that the existence of these incompatible cellular processes largely depends on tightly synchronized expression programs involving ∼30% of genes in the genome. To expand upon current knowledge, we have utilized sensitive proteomic approaches to examine the impact of diurnal rhythms on the protein complement in Cyanothece 51142. We found that 250 proteins accounting for ∼5% of the predicted ORFs from the Cyanothece 51142 genome and 20% of proteins detected under alternating light/dark conditions exhibited periodic oscillations in their abundances. Our results suggest that altered enzyme activities at different phases during the diurnal cycle can be attributed to changes in the abundance of related proteins and key compounds. The integration of global proteomics and transcriptomic data further revealed that post-transcriptional events are important for temporal regulation of processes such as photosynthesis in Cyanothece 51142. This analysis is the first comprehensive report on global quantitative proteomics in a unicellular diazotrophic cyanobacterium and uncovers novel findings about diurnal rhythms.

  14. Association of the Cellular Apoptosis Susceptibility Protein with HBV Infection in Hepatocellular Carcinoma

    Institute of Scientific and Technical Information of China (English)

    Hong Zang; Dong Ji; Qing Shao; Guang-de Zhou; Deng Pan; Shao-jie Xin; Jing-min Zhao; Guo-feng Chen

    2014-01-01

    Objective The cellular apoptosis susceptibility (CAS) protein plays a regulatory role in the induction of cell death in tumor cells. The objective of this study was to investigate the association of the expression of CAS protein with HBV infection in the development of HCC. Methods The expression level of CAS was measured with immunohistochemistry. The occurrence of HBsAg, HBeAg and HBV DNA in HCC were concurrently examined with immunohistochemistry and in situ hybridization, respectively. Results The results showed that the CAS protein was detected in 86% (43/50), 70% (7/10), 15% (3/20) and none (0/20) of livers from patients with HCC, cholangiocarcinoma, cirrhosis and hepatitis, respectively. Furthermore, the level of CAS protein was higher in poorly differentiated tumors than moderately or well differentiated HCC. Interestingly, the CAS was stained significantly stronger in HBV-infected HCC than in non-HBV infected tissues (P < 0.01). Conclusions The expression of CAS is facilitated by HBV infection in HCC, suggesting that CAS might be a prognostic marker and a putative therapeutic target for HCC.

  15. The Intracellular Destiny of the Protein Corona: A Study on its Cellular Internalization and Evolution.

    Science.gov (United States)

    Bertoli, Filippo; Garry, David; Monopoli, Marco P; Salvati, Anna; Dawson, Kenneth A

    2016-11-22

    It has been well established that the early stages of nanoparticle-cell interactions are governed, at least in part, by the layer of proteins and other biomolecules adsorbed and slowly exchanged with the surrounding biological media (biomolecular corona). Subsequent to membrane interactions, nanoparticles are typically internalized into the cell and trafficked along defined pathways such as, in many cases, the endolysosomal pathway. Indeed, if the original corona is partially retained on the nanoparticle surface, the biomolecules in this layer may play an important role in determining subsequent cellular processing. In this work, using a combination of organelle separation and fluorescence labeling of the initial extracellular corona, we clarify its intracellular evolution as nanoparticles travel within the cell. We show that specific proteins present in the original protein corona are retained on the nanoparticles until they accumulate in lysosomes, and, once there, they are degraded. We also report on how different bare surfaces (amino and carboxyl modified) affect the details of this evolution. One overarching discovery is that the same serum proteins can exhibit different intracellular processing when carried inside cells by nanoparticles, as components of their corona, compared to what is observed when they are transported freely from the extracellular medium.

  16. Negative Regulation of STAT3 Protein-mediated Cellular Respiration by SIRT1 Protein

    DEFF Research Database (Denmark)

    Bernier, Michel; Paul, Rajib K; Martin-Montalvo, Alejandro;

    2011-01-01

    In mammals, the transcriptional activity of signal transducer and activator of transcription 3 (STAT3) is regulated by the deacetylase SIRT1. However, whether the newly described nongenomic actions of STAT3 toward mitochondrial oxidative phosphorylation are dependent on SIRT1 is unclear....... In this study, Sirt1 gene knock-out murine embryonic fibroblast (MEF) cells were used to delineate the role of SIRT1 in the regulation of STAT3 mitochondrial function. Here, we show that STAT3 mRNA and protein levels and the accumulation of serine-phosphorylated STAT3 in mitochondria were increased...... significantly in Sirt1-KO cells as compared with wild-type MEFs. Various mitochondrial bioenergetic parameters, such as the oxygen consumption rate in cell cultures, enzyme activities of the electron transport chain complexes in isolated mitochondria, and production of ATP and lactate, indicated that Sirt1-KO...

  17. Influence of HFE variants and cellular iron on monocyte chemoattractant protein-1

    Directory of Open Access Journals (Sweden)

    Simmons Zachary

    2009-02-01

    Full Text Available Abstract Background Polymorphisms in the MHC class 1-like gene known as HFE have been proposed as genetic modifiers of neurodegenerative diseases that include neuroinflammation as part of the disease process. Variants of HFE are relatively common in the general population and are most commonly associated with iron overload, but can promote subclinical cellular iron loading even in the absence of clinically identified disease. The effects of the variants as well as the resulting cellular iron dyshomeostasis potentially impact a number of disease-associated pathways. We tested the hypothesis that the two most common HFE variants, H63D and C282Y, would affect cellular secretion of cytokines and trophic factors. Methods We screened a panel of cytokines and trophic factors using a multiplexed immunoassay in human neuroblastoma SH-SY5Y cells expressing different variants of HFE. The influence of cellular iron secretion on the potent chemokine monocyte chemoattractant protein-1 (MCP-1 was assessed using ferric ammonium citrate and the iron chelator, desferroxamine. Additionally, an antioxidant, Trolox, and an anti-inflammatory, minocycline, were tested for their effects on MCP-1 secretion in the presence of HFE variants. Results Expression of the HFE variants altered the labile iron pool in SH-SY5Y cells. Of the panel of cytokines and trophic factors analyzed, only the release of MCP-1 was affected by the HFE variants. We further examined the relationship between iron and MCP-1 and found MCP-1 secretion tightly associated with intracellular iron status. A potential direct effect of HFE is considered because, despite having similar levels of intracellular iron, the association between HFE genotype and MCP-1 expression was different for the H63D and C282Y HFE variants. Moreover, HFE genotype was a factor in the effect of minocycline, a multifaceted antibiotic used in treating a number of neurologic conditions associated with inflammation, on MCP-1

  18. Quantitative MS-based enzymology of caspases reveals distinct protein substrate specificities, hierarchies, and cellular roles.

    Science.gov (United States)

    Julien, Olivier; Zhuang, Min; Wiita, Arun P; O'Donoghue, Anthony J; Knudsen, Giselle M; Craik, Charles S; Wells, James A

    2016-04-05

    Proteases constitute the largest enzyme family, yet their biological roles are obscured by our rudimentary understanding of their cellular substrates. There are 12 human caspases that play crucial roles in inflammation and cell differentiation and drive the terminal stages of cell death. Recent N-terminomics technologies have begun to enumerate the diverse substrates individual caspases can cleave in complex cell lysates. It is clear that many caspases have shared substrates; however, few data exist about the catalytic efficiencies (kcat/KM) of these substrates, which is critical to understanding their true substrate preferences. In this study, we use quantitative MS to determine the catalytic efficiencies for hundreds of natural protease substrates in cellular lysate for two understudied members: caspase-2 and caspase-6. Most substrates are new, and the cleavage rates vary up to 500-fold. We compare the cleavage rates for common substrates with those found for caspase-3, caspase-7, and caspase-8, involved in apoptosis. There is little correlation in catalytic efficiencies among the five caspases, suggesting each has a unique set of preferred substrates, and thus more specialized roles than previously understood. We synthesized peptide substrates on the basis of protein cleavage sites and found similar catalytic efficiencies between the protein and peptide substrates. These data suggest the rates of proteolysis are dominated more by local primary sequence, and less by the tertiary protein fold. Our studies highlight that global quantitative rate analysis for posttranslational modification enzymes in complex milieus for native substrates is critical to better define their functions and relative sequence of events.

  19. Cellular IAP proteins and LUBAC differentially regulate necrosome-associated RIP1 ubiquitination

    Science.gov (United States)

    de Almagro, M C; Goncharov, T; Newton, K; Vucic, D

    2015-01-01

    Necroptosis is a caspase-independent regulated type of cell death that relies on receptor-interacting protein kinases RIP1 (receptor-interacting protein kinases 1) and RIP3. Tumor necrosis factor-α (TNFα)-stimulated assembly of the TNFR1 (TNF receptor 1)-associated signaling complex leads to the recruitment of RIP1, whose ubiquitination is mediated by the cellular inhibitors of apoptosis (c-IAPs). Translocation of RIP1 to the cytoplasm and association of RIP1 with the necrosome is believed to correlate with deubiquitination of RIP1. However, we found that RIP1 is ubiquitinated with K63 and linear polyubiquitin chains during TNFα, IAP antagonist BV6 and caspase inhibitor zVAD-fmk-induced necroptotic signaling. Furthermore, ubiquitinated RIP1 is associated with the necrosome, and RIP1 ubiquitination in the necrosome coincides with RIP3 phosphorylation. Both cellular IAPs and LUBAC (linear ubiquitin chain assembly complex) modulate RIP1 ubiquitination in IAP antagonist-treated necrotic cells, but they use different mechanisms. c-IAP1 regulates RIP1 recruitment to the necrosome without directly affecting RIP1 ubiquitination, whereas HOIP and HOIL1 mediate linear ubiquitination of RIP1 in the necrosome, but are not essential for necrosome formation. Knockdown of the E3 ligase c-IAP1 decreased RIP1 ubiquitination, necrosome assembly and necroptosis induced by TNFα, BV6 and zVAD-fmk. c-IAP1 deficiency likely decreases necroptotic cell death through the activation of the noncanonical NF-κB pathway and consequent c-IAP2 upregulation. The ability to upregulate c-IAP2 could determine whether c-IAP1 absence will have a positive or negative impact on TNFα-induced necroptotic cell death and necrosome formation. Collectively, these results reveal unexpected complexity of the roles of IAP proteins, IAP antagonists and LUBAC in the regulation of necrosome assembly. PMID:26111062

  20. A cellular protein specifically binds to the 3'-terminal sequences of hepatitis C virus intermediate negative-strand RNA

    Institute of Scientific and Technical Information of China (English)

    王巍; 邓庆丽; 黄开红; 段朝晖; 邵静; 黄志清; 黄志明

    2003-01-01

    ObjectiveTo study the mechanism of the cellular proteins involved in the process of replication of hepatitis C virus (HCV) negative-strand RNA.MethodsUltraviolet (UV) cross-linking was used to identify the cellular proteins that would bind to the 3'-end of HCV negative-strand RNA. Competition experimentwas used to confirm the specificity of this binding, in which excess nonhomologous protein and RNA transcripts were used as competitors. The required binding sequence was determined by mapping, then the binding site was predicted through secondary structure analysis.ResultsA cellular protein of 45 kD (p45) was found to bind specifically to the 3'-endof HCV negative-strand RNA by UV cross-linking. nhomologous proteins and RNA transcripts could not compete out this binding, whereas the unlabeled 3'-endof HCV negative-strand RNA could. Mapping of the protein-binding site suggested that the 3'-end 131-278nt of HCV negative-strand RNA was the possible protein-binding region. Analysis of RNA secondary structure presumed that the potential binding site was located at 194-GAAAGAAC-201. ConclusionThe cellular protein p45 could specifically bind to the secondary structure of the 3'-end of HCV intermediate negative-strand RNA, and may play an important role in HCV RNA replication.

  1. Magnolol Affects Cellular Proliferation, Polyamine Biosynthesis and Catabolism-Linked Protein Expression and Associated Cellular Signaling Pathways in Human Prostate Cancer Cells in vitro

    Directory of Open Access Journals (Sweden)

    Brendan T. McKeown

    2015-01-01

    Full Text Available Background: Prostate cancer is the most commonly diagnosed form of cancer in men in Canada and the United States. Both genetic and environmental factors contribute to the development and progression of many cancers, including prostate cancer. Context and purpose of this study: This study investigated the effects of magnolol, a compound found in the roots and bark of the magnolia tree Magnolia officinalis, on cellular proliferation and proliferation-linked activities of PC3 human prostate cancer cells in vitro. Results: PC3 cells exposed to magnolol at a concentration of 80 μM for 6 hours exhibited decreased protein expression of ornithine decarboxylase, a key regulator in polyamine biosynthesis, as well as affecting the expression of other proteins involved in polyamine biosynthesis and catabolism. Furthermore, protein expression of the R2 subunit of ribonucleotide reductase, a key regulatory protein associated with DNA synthesis, was significantly decreased. Finally, the MAPK (mitogen-activated protein kinase, PI3K (phosphatidylinositol 3-kinase, NFκB (nuclear factor of kappa-light-chain-enhancer of activated B cells and AP-1 (activator protein 1 cellular signaling pathways were assayed to determine which, if any, of these pathways magnolol exposure would alter. Protein expressions of p-JNK-1 and c-jun were significantly increased while p-p38, JNK-1/2, PI3Kp85, p-PI3Kp85, p-Akt, NFκBp65, p-IκBα and IκBα protein expressions were significantly decreased. Conclusions: These alterations further support the anti-proliferative effects of magnolol on PC3 human prostate cancer cells in vitro and suggest that magnolol may have potential as a novel anti-prostate cancer agent.

  2. GCK-MODY diabetes associated with protein misfolding, cellular self-association and degradation.

    Science.gov (United States)

    Negahdar, Maria; Aukrust, Ingvild; Johansson, Bente B; Molnes, Janne; Molven, Anders; Matschinsky, Franz M; Søvik, Oddmund; Kulkarni, Rohit N; Flatmark, Torgeir; Njølstad, Pål Rasmus; Bjørkhaug, Lise

    2012-11-01

    GCK-MODY, dominantly inherited mild fasting hyperglycemia, has been associated with >600 different mutations in the glucokinase (GK)-encoding gene (GCK). When expressed as recombinant pancreatic proteins, some mutations result in enzymes with normal/near-normal catalytic properties. The molecular mechanism(s) of GCK-MODY due to these mutations has remained elusive. Here, we aimed to explore the molecular mechanisms for two such catalytically 'normal' GCK mutations (S263P and G264S) in the F260-L270 loop of GK. When stably overexpressed in HEK293 cells and MIN6 β-cells, the S263P- and G264S-encoded mutations generated misfolded proteins with an increased rate of degradation (S263P>G264S) by the protein quality control machinery, and a propensity to self-associate (G264S>S263P) and form dimers (SDS resistant) and aggregates (partly Triton X-100 insoluble), as determined by pulse-chase experiments and subcellular fractionation. Thus, the GCK-MODY mutations S263P and G264S lead to protein misfolding causing destabilization, cellular dimerization/aggregation and enhanced rate of degradation. In silico predicted conformational changes of the F260-L270 loop structure are considered to mediate the dimerization of both mutant proteins by a domain swapping mechanism. Thus, similar properties may represent the molecular mechanisms for additional unexplained GCK-MODY mutations, and may also contribute to the disease mechanism in other previously characterized GCK-MODY inactivating mutations.

  3. Roadmap to cellular reprogramming--manipulating transcriptional networks with DNA, RNA, proteins and small molecules.

    Science.gov (United States)

    Wörsdörfer, P; Thier, M; Kadari, A; Edenhofer, F

    2013-06-01

    Recent reports demonstrate that the plasticity of mammalian somatic cells is much higher than previously assumed and that ectopic expression of transcription factors may have the potential to induce the conversion of any cell type into another. Fibroblast cells can be converted into embryonic stem cell-like cells, neural cells, cardiomyocytes, macrophage-like cells as well as blood progenitors. Additionally, the conversion of astrocytes into neurons or neural stem cells into monocytes has been demonstrated. Nowadays, in the era of systems biology, continuously growing holistic data sets are providing increasing insights into core transcriptional networks and cellular signaling pathways. This knowledge enables cell biologists to understand how cellular fate is determined and how it could be manipulated. As a consequence for biomedical applications, it might be soon possible to convert patient specific somatic cells directly into desired transplantable other cell types. The clinical value, however, of such reprogrammed cells is currently limited due to the invasiveness of methods applied to induce reprogramming factor activity. This review will focus on experimental strategies to ectopically induce cell fate modulators. We will emphasize those strategies that enable efficient and robust overexpression of transcription factors by minimal genetic alterations of the host genome. Furthermore, we will discuss procedures devoid of any genomic manipulation, such as the direct delivery of mRNA, proteins, or the use of small molecules. By this, we aim to give a comprehensive overview on state of the art techniques that harbor the potential to generate safe reprogrammed cells for clinical applications.

  4. Highly efficient enzyme encapsulation in a protein nanocage: towards enzyme catalysis in a cellular nanocompartment mimic

    Science.gov (United States)

    Schoonen, Lise; Nolte, Roeland J. M.; van Hest, Jan C. M.

    2016-07-01

    The study of enzyme behavior in small nanocompartments is crucial for the understanding of biocatalytic processes in the cellular environment. We have developed an enzymatic conjugation strategy to attach a model enzyme to the interior of a cowpea chlorotic mottle virus capsid. It is shown that with this methodology high encapsulation efficiencies can be achieved. Additionally, we demonstrate that the encapsulation does not affect the enzyme performance in terms of a decreased activity or a hampered substrate diffusion. Finally, it is shown that the encapsulated enzymes are protected against proteases. We believe that our strategy can be used to study enzyme kinetics in an environment that approaches physiological conditions.The study of enzyme behavior in small nanocompartments is crucial for the understanding of biocatalytic processes in the cellular environment. We have developed an enzymatic conjugation strategy to attach a model enzyme to the interior of a cowpea chlorotic mottle virus capsid. It is shown that with this methodology high encapsulation efficiencies can be achieved. Additionally, we demonstrate that the encapsulation does not affect the enzyme performance in terms of a decreased activity or a hampered substrate diffusion. Finally, it is shown that the encapsulated enzymes are protected against proteases. We believe that our strategy can be used to study enzyme kinetics in an environment that approaches physiological conditions. Electronic supplementary information (ESI) available: Experimental procedures for the cloning, expression, and purification of all proteins, as well as supplementary figures and calculations. See DOI: 10.1039/c6nr04181g

  5. Cellular prion protein is expressed in a subset of neuroendocrine cells of the rat gastrointestinal tract.

    Science.gov (United States)

    Marcos, Zuberoa; Pffeifer, Kristine; Bodegas, María E; Sesma, María P; Guembe, Laura

    2004-10-01

    Prion diseases are believed to develop from the conformational change of normal cellular prion protein (PrPc) to a pathogenic isoform (PrPsc). PrPc is present in both the central nervous system and many peripheral tissues, although protein concentration is significantly lower in non-neuronal tissues. PrPc expression is essential for internalization and replication of the infectious agent. Several works have pointed to the gastrointestinal (GI) tract as the principal site of entry of PrPsc, but how passage through the GI mucosa occurs is not yet known. Here we studied PrPc expression using Western blot, RT-PCR, and immunohistochemistry in rat GI tract. PrPc mRNA and protein were detected in corpus, antrum, duodenum, and colon. Immunoreactivity was found in scattered cells of the GI epithelium. With double immunofluorescence, these cells have been identified as neuroendocrine cells. PrPc immunostaining was found in subsets of histamine, somatostatin (Som), ghrelin, gastrin (G), and serotonin (5HT) cells in stomach. In small and large bowel, PrPc cells co-localized with subpopulations of 5HT-, Som-, G-, and peptide YY-immunolabeled cells. Our results provide evidence for a possible and important role of endocrine cells in the internalization of PrPsc from gut lumen.

  6. Simian virus 40 late proteins possess lytic properties that render them capable of permeabilizing cellular membranes.

    Science.gov (United States)

    Daniels, Robert; Rusan, Nasser M; Wilbuer, Anne-Kathrin; Norkin, Leonard C; Wadsworth, Patricia; Hebert, Daniel N

    2006-07-01

    Many nonenveloped viruses have evolved an infectious cycle that culminates in the lysis or permeabilization of the host to enable viral release. How these viruses initiate the lytic event is largely unknown. Here, we demonstrated that the simian virus 40 progeny accumulated at the nuclear envelope prior to the permeabilization of the nuclear, endoplasmic reticulum, and plasma membranes at a time which corresponded with the release of the progeny. The permeabilization of these cellular membranes temporally correlated with late protein expression and was not observed upon the inhibition of their synthesis. To address whether one or more of the late proteins possessed an inherent capacity to induce membrane permeabilization, we examined the permeability of Escherichia coli that separately expressed the late proteins. VP2 and VP3, but not VP1, caused the permeabilization of bacterial membranes. Additionally, VP3 expression resulted in bacterial cell lysis. These findings demonstrate that VP3 possesses an inherent lytic property that is independent of eukaryotic signaling or cell death pathways.

  7. Cellular Prion Protein Promotes Regeneration of Adult Muscle Tissue ▿ †

    Science.gov (United States)

    Stella, Roberto; Massimino, Maria Lina; Sandri, Marco; Sorgato, M. Catia; Bertoli, Alessandro

    2010-01-01

    It is now well established that the conversion of the cellular prion protein, PrPC, into its anomalous conformer, PrPSc, is central to the onset of prion disease. However, both the mechanism of prion-related neurodegeneration and the physiologic role of PrPC are still unknown. The use of animal and cell models has suggested a number of putative functions for the protein, including cell signaling, adhesion, proliferation, and differentiation. Given that skeletal muscles express significant amounts of PrPC and have been related to PrPC pathophysiology, in the present study, we used skeletal muscles to analyze whether the protein plays a role in adult morphogenesis. We employed an in vivo paradigm that allowed us to compare the regeneration of acutely damaged hind-limb tibialis anterior muscles of mice expressing, or not expressing, PrPC. Using morphometric and biochemical parameters, we provide compelling evidence that the absence of PrPC significantly slows the regeneration process compared to wild-type muscles by attenuating the stress-activated p38 pathway, and the consequent exit from the cell cycle, of myogenic precursor cells. Demonstrating the specificity of this finding, restoring PrPC expression completely rescued the muscle phenotype evidenced in the absence of PrPC. PMID:20679477

  8. Combinatorial effects of continuous protein synthesis, ERK-signaling, and reactive oxygen species on induction of cellular senescence.

    Science.gov (United States)

    Takauji, Yuki; En, Atsuki; Miki, Kensuke; Ayusawa, Dai; Fujii, Michihiko

    2016-07-15

    Mammalian cells, when treated with sub-lethal doses of genotoxic stresses, slow down DNA synthesis but continue protein synthesis. Thus, these cells show an accumulation of proteins and undergo unbalanced growth. In the previous studies, we have shown that HeLa cells treated with excess thymidine or camptothecin undergo unbalanced growth, and prolonged unbalanced growth causes induction of cellular senescence, which is suppressed by restriction of protein synthesis or inhibition of ERK-signaling. In this study, we found that restriction of protein synthesis, inhibition of ERK-signaling, and elimination of reactive oxygen species showed a combinatorial effect on suppression of cellular senescence induced by excess thymidine or camptothecin. Of these, restriction of protein synthesis most effectively suppressed cellular senescence. Importantly, a similar combinatorial effect was observed in replicative senescence in normal human diploid fibroblasts. Our findings suggested that various stresses were cumulatively involved in cellular senescence, and suppression of cellular senescence was improved by combining the treatments that reduce the stresses.

  9. The eukaryotic Pso2/Snm1/Artemis proteins and their function as genomic and cellular caretakers

    Directory of Open Access Journals (Sweden)

    D. Bonatto

    2005-03-01

    Full Text Available DNA double-strand breaks (DSBs represent a major threat to the genomic stability of eukaryotic cells. DNA repair mechanisms such as non-homologous end joining (NHEJ are responsible for the maintenance of eukaryotic genomes. Dysfunction of one or more of the many protein complexes that function in NHEJ can lead to sensitivity to DNA damaging agents, apoptosis, genomic instability, and severe combined immunodeficiency. One protein, Pso2p, was shown to participate in the repair of DSBs induced by DNA inter-strand cross-linking (ICL agents such as cisplatin, nitrogen mustard or photo-activated bi-functional psoralens. The molecular function of Pso2p in DNA repair is unknown, but yeast and mammalian cell line mutants for PSO2 show the same cellular responses as strains with defects in NHEJ, e.g., sensitivity to ICLs and apoptosis. The Pso2p human homologue Artemis participates in V(DJ recombination. Mutations in Artemis induce a variety of immunological deficiencies, a predisposition to lymphomas, and an increase in chromosomal aberrations. In order to better understand the role of Pso2p in the repair of DSBs generated as repair intermediates of ICLs, an in silico approach was used to characterize the catalytic domain of Pso2p, which led to identification of novel Pso2p homologues in other organisms. Moreover, we found the catalytic core of Pso2p fused to different domains. In plants, a specific ATP-dependent DNA ligase I contains the catalytic core of Pso2p, constituting a new DNA ligase family, which was named LIG6. The possible functions of Pso2p/Artemis/Lig6p in NHEJ and V(DJ recombination and in other cellular metabolic reactions are discussed.

  10. Biopolymer stochastic moments. I. Modeling human rhinovirus cellular recognition with protein surface electrostatic moments.

    Science.gov (United States)

    González-Díaz, Humberto; Uriarte, Eugenio

    2005-04-05

    Stochastic moments may be applied as molecular descriptors in quantitative structure-activity relationship (QSAR) studies for small molecules (H. González-Dìaz et al., Journal of Molecular Modeling, 2002, Vol. 8, pp. 237-245; 2003, Vol. 9, pp. 395-407). However, applications in the field of biopolymers are less known. Recently, the MARCH-INSIDE approach has been generalized to encode structural features of proteins and other biopolymers (H. González-Dáaz et al., Bioinformatics, 2003, Vol. 19, pp. 2079-2087; Bioorganic & Medicinal Chemistry Letters, 2004, Vol. 14, pp. 4691-4695; Polymers, 2004, Vol. 45, pp. 3845-3853; Bioorganic & Medicinal Chemistry, 2005, Vol. 13, pp. 323-331). The present article attempts to extend this research by introducing for the first time stochastic moments for a surface road map of viral proteins. These moments are afterward used to seek a model that predicts the cellular receptor for human rhinoviruses. The model correctly classified 100% of 10 viruses binding to low-density lipoprotein receptor (LDLR) and 88.9% of 9 viruses binding to the intracellular adhesion molecule (ICAM) receptors in training. The same results have been obtained in four cross-validation experiments using a resubstitution technique. The present model favorably compares, in terms of complexity, with other previously reported based on entropy considerations, and offers a quantitative basis for the visual rule previously reported by Vlasak et al.

  11. Application of elastin-mimetic recombinant proteins in chemotherapeutics delivery, cellular engineering, and regenerative medicine.

    Science.gov (United States)

    Jeon, Won Bae

    2013-01-01

    With the remarkable increase in the fields of biomedical engineering and regenerative medicine, biomaterial design has become an indispensable approach for developing the biocompatible carriers for drug or gene cargo and extracellular matrix (ECM) for cell survival, proliferation and differentiation. Native ECM materials derived from animal tissues were believed to be the best choices for tissue engineering. However, possible pathogen contamination by cellular remnants from foreign animal tissues is an unavoidable issue that has limited the use of native ECM for human benefit. Some synthetic polymers have been used as alternative materials for manufacturing native ECM because of the biodegradability and ease of large-scale production of the polymers. However, the inherent polydispersity of the polymers causes batch-to-batch variation in polymer composition and possible cytotoxic interactions between chemical matrices and neighboring cells or tissues have not yet been fully resolved. Elastin-like proteins (ELPs) are genetically engineered biopolymers modeled after the naturally occurring tropoelastin and have emerged as promising materials for biomedical applications because they are biocompatible, non-immunogenic and biodegradable, and their composition, mechanical stiffness and even fate within the cell can be controlled at the gene level. This commentary highlights the recent progresses in the development of the ELP-based recombinant proteins that are being increasingly used for the delivery of chemotherapeutics and to provide a cell-friendly ECM environment.

  12. The adaptor protein FHL2 enhances the cellular innate immune response to influenza A virus infection.

    Science.gov (United States)

    Nordhoff, Carolin; Hillesheim, Andrea; Walter, Beate M; Haasbach, Emanuel; Planz, Oliver; Ehrhardt, Christina; Ludwig, Stephan; Wixler, Viktor

    2012-07-01

    The innate immune response of influenza A virus-infected cells is predominantly mediated by type I interferon-induced proteins. Expression of the interferon β (IFNβ) itself is initiated by accumulating viral RNA and is transmitted by different signalling cascades that feed into activation of the three transcriptional elements located in the IFNβ promoter, AP-1, IRF-3 and NF-κB. FHL2 (four-and-a-half LIM domain protein 2) is an adaptor molecule that shuttles between membrane and nucleus regulating signalling cascades and gene transcription. Here we describe FHL2 as a novel regulator of influenza A virus propagation. Using mouse FHL2 wild-type, knockout and rescued cells and human epithelial cells with different expression levels of FHL2 we showed that FHL2 decreases influenza A virus propagation by regulating the intrinsic cellular antiviral immune response. On virus infection FHL2 translocates into the nucleus, potentiating the IRF-3-dependent transcription of the IFNβ gene.

  13. The Dengue Virus NS5 Protein Intrudes in the Cellular Spliceosome and Modulates Splicing

    Science.gov (United States)

    Shah, Priya; Pozzi, Berta; Gebhard, Leopoldo G.; Mammi, Pablo; Yanovsky, Marcelo J.; Andino, Raul; Krogan, Nevan; Srebrow, Anabella; Gamarnik, Andrea V.

    2016-01-01

    Dengue virus NS5 protein plays multiple functions in the cytoplasm of infected cells, enabling viral RNA replication and counteracting host antiviral responses. Here, we demonstrate a novel function of NS5 in the nucleus where it interferes with cellular splicing. Using global proteomic analysis of infected cells together with functional studies, we found that NS5 binds spliceosome complexes and modulates endogenous splicing as well as minigene-derived alternative splicing patterns. In particular, we show that NS5 alone, or in the context of viral infection, interacts with core components of the U5 snRNP particle, CD2BP2 and DDX23, alters the inclusion/exclusion ratio of alternative splicing events, and changes mRNA isoform abundance of known antiviral factors. Interestingly, a genome wide transcriptome analysis, using recently developed bioinformatics tools, revealed an increase of intron retention upon dengue virus infection, and viral replication was improved by silencing specific U5 components. Different mechanistic studies indicate that binding of NS5 to the spliceosome reduces the efficiency of pre-mRNA processing, independently of NS5 enzymatic activities. We propose that NS5 binding to U5 snRNP proteins hijacks the splicing machinery resulting in a less restrictive environment for viral replication. PMID:27575636

  14. The Cellular Prion Protein Controls Notch Signaling in Neural Stem/Progenitor Cells.

    Science.gov (United States)

    Martin-Lannerée, Séverine; Halliez, Sophie; Hirsch, Théo Z; Hernandez-Rapp, Julia; Passet, Bruno; Tomkiewicz, Céline; Villa-Diaz, Ana; Torres, Juan-Maria; Launay, Jean-Marie; Béringue, Vincent; Vilotte, Jean-Luc; Mouillet-Richard, Sophie

    2017-03-01

    The prion protein is infamous for its involvement in a group of neurodegenerative diseases known as Transmissible Spongiform Encephalopathies. In the longstanding quest to decipher the physiological function of its cellular isoform, PrP(C) , the discovery of its participation to the self-renewal of hematopoietic and neural stem cells has cast a new spotlight on its potential role in stem cell biology. However, still little is known on the cellular and molecular mechanisms at play. Here, by combining in vitro and in vivo murine models of PrP(C) depletion, we establish that PrP(C) deficiency severely affects the Notch pathway, which plays a major role in neural stem cell maintenance. We document that the absence of PrP(C) in a neuroepithelial cell line or in primary neurospheres is associated with drastically reduced expression of Notch ligands and receptors, resulting in decreased levels of Notch target genes. Similar alterations of the Notch pathway are recovered in the neuroepithelium of Prnp(-/-) embryos during a developmental window encompassing neural tube closure. In addition, in line with Notch defects, our data show that the absence of PrP(C) results in altered expression of Nestin and Olig2 as well as N-cadherin distribution. We further provide evidence that PrP(C) controls the expression of the epidermal growth factor receptor (EGFR) downstream from Notch. Finally, we unveil a negative feedback action of EGFR on both Notch and PrP(C) . As a whole, our study delineates a molecular scenario through which PrP(C) takes part to the self-renewal of neural stem and progenitor cells. Stem Cells 2017;35:754-765.

  15. The Cellular Proteins Grb2 and DDX3 Are Increased upon Human Cytomegalovirus Infection and Act in a Proviral Fashion.

    Science.gov (United States)

    Cavignac, Yolaine; Lieber, Diana; Laib Sampaio, Kerstin; Madlung, Johannes; Lamkemeyer, Tobias; Jahn, Gerhard; Nordheim, Alfred; Sinzger, Christian

    2015-01-01

    While it is well established that human cytomegalovirus (HCMV) upregulates many cellular proteins and incorporates several of them into its virion, little is known about the functional relevance of such virus-host interactions. Two cellular proteins, Grb2 and DDX3, gained our interest as they appeared enriched in virion particles and this incorporation depended on the viral tegument protein pp65, suggesting a functional relevance. We therefore tested whether the level of these proteins is altered upon HCMV infection and whether they support viral replication. Immunoblotting analyses of cellular fractions showed increased levels of both proteins in infected cells with a maximum at 2 d p.i. and a reduction of the soluble Grb2 fraction. Knockdown of either gene by transfection of siRNAs reduced viral spread not only of the cell culture adapted HCMV strain TB40/E but also of recent clinical isolates. Apparently, Grb2 and DDX3 are proviral cellular factors that are upregulated in infected cells.

  16. The Cellular Proteins Grb2 and DDX3 Are Increased upon Human Cytomegalovirus Infection and Act in a Proviral Fashion.

    Directory of Open Access Journals (Sweden)

    Yolaine Cavignac

    Full Text Available While it is well established that human cytomegalovirus (HCMV upregulates many cellular proteins and incorporates several of them into its virion, little is known about the functional relevance of such virus-host interactions. Two cellular proteins, Grb2 and DDX3, gained our interest as they appeared enriched in virion particles and this incorporation depended on the viral tegument protein pp65, suggesting a functional relevance. We therefore tested whether the level of these proteins is altered upon HCMV infection and whether they support viral replication. Immunoblotting analyses of cellular fractions showed increased levels of both proteins in infected cells with a maximum at 2 d p.i. and a reduction of the soluble Grb2 fraction. Knockdown of either gene by transfection of siRNAs reduced viral spread not only of the cell culture adapted HCMV strain TB40/E but also of recent clinical isolates. Apparently, Grb2 and DDX3 are proviral cellular factors that are upregulated in infected cells.

  17. Herpes simplex virus 1 VP22 regulates translocation of multiple viral and cellular proteins and promotes neurovirulence.

    Science.gov (United States)

    Tanaka, Michiko; Kato, Akihisa; Satoh, Yuko; Ide, Takahiro; Sagou, Ken; Kimura, Kayo; Hasegawa, Hideki; Kawaguchi, Yasushi

    2012-05-01

    Herpes simplex virus 1 (HSV-1) protein VP22, encoded by the UL49 gene, is a major virion tegument protein. In the present study, we showed that VP22 was required for efficient redistribution of viral proteins VP16, VP26, ICP0, ICP4, and ICP27 and of cellular protein Hsc-70 to the cytoplasm of infected cells. We found that two dileucine motifs in VP22, at amino acids 235 and 236 and amino acids 251 and 252, were necessary for VP22 regulation of the proper cytoplasmic localization of these viral and cellular proteins. The dileucine motifs were also required for proper cytoplasmic localization of VP22 itself and for optimal expression of viral proteins VP16, VP22, ICP0, UL41, and glycoprotein B. Interestingly, a recombinant mutant virus with alanines substituted for the dileucines at amino acids 251 and 252 had a 50% lethal dose (LD(50)) for neurovirulence in mice following intracerebral inoculation about 10(3)-fold lower than the LD(50) of the repaired virus. Furthermore, the replication and spread of this mutant virus in the brains of mice following intracerebral inoculation were significantly impaired relative to those of the repaired virus. The ability of VP22 to regulate the localization and expression of various viral and cellular proteins, as shown in this study, was correlated with an increase in viral replication and neurovirulence in the experimental murine model. Thus, HSV-1 VP22 is a significant neurovirulence factor in vivo.

  18. Vif proteins of human and simian immunodeficiency viruses require cellular CBFβ to degrade APOBEC3 restriction factors.

    Science.gov (United States)

    Hultquist, Judd F; Binka, Mawuena; LaRue, Rebecca S; Simon, Viviana; Harris, Reuben S

    2012-03-01

    HIV-1 requires the cellular transcription factor CBFβ to stabilize its accessory protein Vif and promote APOBEC3G degradation. Here, we demonstrate that both isoforms of CBFβ allow for increased steady-state levels of Vif, enhanced APOBEC3G degradation, and increased viral infectivity. This conserved functional interaction enhances the steady-state levels of Vif proteins from multiple HIV-1 subtypes and is required for the degradation of all human and rhesus Vif-sensitive APOBEC3 proteins by their respective lentiviral Vif proteins.

  19. Signal transduction across cellular membranes can be mediated by coupling of the clustering of anchored proteins in both leaflets

    Science.gov (United States)

    Yue, Tongtao; Zhang, Xianren

    2012-01-01

    One key question in signal transduction is how the signal is relayed from the outer leaflet of a cellular membrane to the inner leaflet. Using a simulation model, a mechanism for the mediation of signal transduction is proposed here in which the coupling between membrane proteins in different leaflets can be achieved by the clustering of anchored proteins, without recruiting transmembrane proteins. Depending on the hydrophobic length of the anchored proteins, three coupling patterns, including face-to-face clustering, interdigitated clustering, and weak-coupled clustering, are observed in this work. This observation provides a possible explanation of how a particular downstream signaling pathway is selected.

  20. Activation of the cellular unfolded protein response by recombinant adeno-associated virus vectors.

    Directory of Open Access Journals (Sweden)

    Balaji Balakrishnan

    Full Text Available The unfolded protein response (UPR is a stress-induced cyto-protective mechanism elicited towards an influx of large amount of proteins in the endoplasmic reticulum (ER. In the present study, we evaluated if AAV manipulates the UPR pathways during its infection. We first examined the role of the three major UPR axes, namely, endoribonuclease inositol-requiring enzyme-1 (IRE1α, activating transcription factor 6 (ATF6 and PKR-like ER kinase (PERK in AAV infected cells. Total RNA from mock or AAV infected HeLa cells were used to determine the levels of 8 different ER-stress responsive transcripts from these pathways. We observed a significant up-regulation of IRE1α (up to 11 fold and PERK (up to 8 fold genes 12-48 hours after infection with self-complementary (scAAV2 but less prominent with single-stranded (ssAAV2 vectors. Further studies demonstrated that scAAV1 and scAAV6 also induce cellular UPR in vitro, with AAV1 vectors activating the PERK pathway (3 fold while AAV6 vectors induced a significant increase on all the three major UPR pathways [6-16 fold]. These data suggest that the type and strength of UPR activation is dependent on the viral capsid. We then examined if transient inhibition of UPR pathways by RNA interference has an effect on AAV transduction. siRNA mediated silencing of PERK and IRE1α had a modest effect on AAV2 and AAV6 mediated gene expression (∼1.5-2 fold in vitro. Furthermore, hepatic gene transfer of scAAV2 vectors in vivo, strongly elevated IRE1α and PERK pathways (2 and 3.5 fold, respectively. However, when animals were pre-treated with a pharmacological UPR inhibitor (metformin during scAAV2 gene transfer, the UPR signalling and its subsequent inflammatory response was attenuated concomitant to a modest 2.8 fold increase in transgene expression. Collectively, these data suggest that AAV vectors activate the cellular UPR pathways and their selective inhibition may be beneficial during AAV mediated gene transfer.

  1. Validation of a prefractionation method followed by two-dimensional electrophoresis – Applied to cerebrospinal fluid proteins from frontotemporal dementia patients

    Directory of Open Access Journals (Sweden)

    Sjögren Magnus

    2004-11-01

    Full Text Available Abstract Background The aim of this study was firstly, to improve and validate a cerebrospinal fluid (CSF prefractionation method followed by two-dimensional electrophoresis (2-DE and secondly, using this strategy to investigate differences between the CSF proteome of frontotemporal dementia (FTD patients and controls. From each subject three ml of CSF was prefractionated using liquid phase isoelectric focusing prior to 2-DE. Results With respect to protein recovery and purification potential, ethanol precipitation of the prefractionated CSF sample was found superior, after testing several sample preparation methods. The reproducibility of prefractionated CSF analyzed on 2-D gels was comparable to direct 2-DE analysis of CSF. The protein spots on the prefractionated 2-D gels had an increased intensity, indicating a higher protein concentration, compared to direct 2-D gels. Prefractionated 2-DE analysis of FTD and control CSF showed that 26 protein spots were changed at least two fold. Using mass spectrometry, 13 of these protein spots were identified, including retinol-binding protein, Zn-α-2-glycoprotein, proapolipoproteinA1, β-2-microglobulin, transthyretin, albumin and alloalbumin. Conclusion The results suggest that the prefractionated 2-DE method can be useful for enrichment of CSF proteins and may provide a new tool to investigate the pathology of neurodegenerative diseases. This study confirmed reduced levels of retinol-binding protein and revealed some new biomarker candidates for FTD.

  2. The comparison of protein-entrapped liposomes and lipoparticles: preparation, characterization, and efficacy of cellular uptake

    Directory of Open Access Journals (Sweden)

    Chang WK

    2011-10-01

    the liposomes at 3.3 hours. A Caco-2 cell model was used for evaluating the cytotoxicity and cell uptake efficiency of the PEG-modified lipoparticles. At a lipid content below 0.25 mM, neither the liposomes nor the lipoparticles caused significant cellular cytotoxicity (P < 0.01 and FITC-BSA was significantly taken up into cells within 60 minutes (P < 0.01. Keywords: liposomes, lipoparticles, formulation, protein, stability

  3. The Coxsackievirus-Adenovirus Receptor Protein Can Function as a Cellular Attachment Protein for Adenovirus Serotypes from Subgroups A, C, D, E, and F

    OpenAIRE

    Roelvink, Peter W.; Lizonova, Alena; Lee, Jennifer G. M.; Li, Yuan; Bergelson, Jeffrey M.; Finberg, Robert W.; Douglas E Brough; Kovesdi, Imre; Wickham, Thomas J.

    1998-01-01

    Attachment of an adenovirus (Ad) to a cell is mediated by the capsid fiber protein. To date, only the cellular fiber receptor for subgroup C serotypes 2 and 5, the so-called coxsackievirus-adenovirus receptor (CAR) protein, has been identified and cloned. Previous data suggested that the fiber of the subgroup D serotype Ad9 also recognizes CAR, since Ad9 and Ad2 fiber knobs cross-blocked each other’s cellular binding. Recombinant fiber knobs and 3H-labeled Ad virions from serotypes representi...

  4. The Cellular Prion Protein Prevents Copper-Induced Inhibition of P2X4 Receptors

    Science.gov (United States)

    Lorca, Ramón A.; Varela-Nallar, Lorena; Inestrosa, Nibaldo C.; Huidobro-Toro, J. Pablo

    2011-01-01

    Although the physiological function of the cellular prion protein (PrPC) remains unknown, several evidences support the notion of its role in copper homeostasis. PrPC binds Cu2+ through a domain composed by four to five repeats of eight amino acids. Previously, we have shown that the perfusion of this domain prevents and reverses the inhibition by Cu2+ of the adenosine triphosphate (ATP)-evoked currents in the P2X4 receptor subtype, highlighting a modulatory role for PrPC in synaptic transmission through regulation of Cu2+ levels. Here, we study the effect of full-length PrPC in Cu2+ inhibition of P2X4 receptor when both are coexpressed. PrPC expression does not significantly change the ATP concentration-response curve in oocytes expressing P2X4 receptors. However, the presence of PrPC reduces the inhibition by Cu2+ of the ATP-elicited currents in these oocytes, confirming our previous observations with the Cu2+ binding domain. Thus, our observations suggest a role for PrPC in modulating synaptic activity through binding of extracellular Cu2+. PMID:22114745

  5. The Cellular Prion Protein Prevents Copper-Induced Inhibition of P2X4 Receptors

    Directory of Open Access Journals (Sweden)

    Ramón A. Lorca

    2011-01-01

    Full Text Available Although the physiological function of the cellular prion protein (PrPC remains unknown, several evidences support the notion of its role in copper homeostasis. PrPC binds Cu2+ through a domain composed by four to five repeats of eight amino acids. Previously, we have shown that the perfusion of this domain prevents and reverses the inhibition by Cu2+ of the adenosine triphosphate (ATP-evoked currents in the P2X4 receptor subtype, highlighting a modulatory role for PrPC in synaptic transmission through regulation of Cu2+ levels. Here, we study the effect of full-length PrPC in Cu2+ inhibition of P2X4 receptor when both are coexpressed. PrPC expression does not significantly change the ATP concentration-response curve in oocytes expressing P2X4 receptors. However, the presence of PrPC reduces the inhibition by Cu2+ of the ATP-elicited currents in these oocytes, confirming our previous observations with the Cu2+ binding domain. Thus, our observations suggest a role for PrPC in modulating synaptic activity through binding of extracellular Cu2+.

  6. Cloning, expression and cellular localization of Daphnia pulex senescence-associated protein, DpSAP.

    Science.gov (United States)

    Liu, Ajing; Kong, Ling; Zhang, Mingqing; Wu, Donglei; Wang, Danli; Zhao, Yunlong

    2014-01-25

    Daphnia (water fleas) are small crustaceans that undergo an unusual switch from asexual to sexual reproduction that is dependent on environmental conditions. In this study, a senescence-associated protein (SAP) from the common freshwater species Daphnia pulex was cloned using primers based on homologous sequences and rapid amplification of cDNA ends (RACE). Real-time PCR was employed to quantify the expression of D. pulex SAP (DpSAP) in individual organisms. The role of DpSAP in the reproductive transformation was further investigated in both parthenogenetic and sexual females by using digoxin-labeled SAP RNA probes and RNA whole-mount in situ hybridization. DpSAP was more highly expressed in sexual females, indicating a role in growth and reproduction. Cellular localization studies using RNA whole-mount in situ hybridization showed specific expression in the second tentacle joints. These expression patterns suggest an important role for DpSAP in the reproductive transformation of D. pulex.

  7. A structural basis for cellular uptake of GST-fold proteins.

    Directory of Open Access Journals (Sweden)

    Melanie J Morris

    Full Text Available It has recently emerged that glutathione transferase enzymes (GSTs and other structurally related molecules can be translocated from the external medium into many different cell types. In this study we aim to explore in detail, the structural features that govern cell translocation and by dissecting the human GST enzyme GSTM2-2 we quantatively demonstrate that the α-helical C-terminal domain (GST-C is responsible for this property. Attempts to further examine the constituent helices within GST-C resulted in a reduction in cell translocation efficiency, indicating that the intrinsic GST-C domain structure is necessary for maximal cell translocation capacity. In particular, it was noted that the α-6 helix of GST-C plays a stabilising role in the fold of this domain. By destabilising the conformation of GST-C, an increase in cell translocation efficiency of up to ∼2-fold was observed. The structural stability profiles of these protein constructs have been investigated by circular dichroism and differential scanning fluorimetry measurements and found to impact upon their cell translocation efficiency. These experiments suggest that the globular, helical domain in the 'GST-fold' structural motif plays a role in influencing cellular uptake, and that changes that affect the conformational stability of GST-C can significantly influence cell translocation efficiency.

  8. DNA Methylation of Cellular Retinoic Acid-Binding Proteins in Cervical Cancer

    Science.gov (United States)

    Arellano-Ortiz, Ana L.; Salcedo-Vargas, Mauricio; Vargas-Requena, Claudia L.; López-Díaz, José A.; De la Mora-Covarrubias, Antonio; Silva-Espinoza, Juan C.; Jiménez-Vega, Florinda

    2016-01-01

    This study determined the methylation status of cellular retinoic acid-binding protein (CRABP) gene promoters and associated them with demographic characteristics, habits, and the presence of human papilloma virus (HPV) in patients with cervical cancer (CC), low and high squamous intraepithelial lesions, and no intraepithelial lesion. Women (n = 158) were selected from the Colposcopy Clinic of Sanitary Jurisdiction II in Ciudad Juarez, Chihuahua, Mexico. Demographic characteristics and habit information were collected. Cervical biopsy and endocervical scraping were used to determine methylation in promoter regions by methylation-specific polymerase chain reaction technique. We found hemi-methylation patterns in the promoter regions of CRABP1 and CRABP2; there was 28.5% hemi-methylation in CRABP1 and 7.0% in that of CRABP2. Methylation in CRABP1 was associated with age (≥35 years, P = 0.002), family history of cancer (P = 0.032), the presence of HPV-16 (P = 0.013), and no alcohol intake (P = 0.035). These epigenetic changes could be involved in the CC process, and CRABP1 has the potential to be a predictive molecular marker of retinoid therapy response. PMID:27867303

  9. Exploiting the multiplexing capabilities of tandem mass tags for high-throughput estimation of cellular protein abundances by mass spectrometry.

    Science.gov (United States)

    Ahrné, Erik; Martinez-Segura, Amalia; Syed, Afzal Pasha; Vina-Vilaseca, Arnau; Gruber, Andreas J; Marguerat, Samuel; Schmidt, Alexander

    2015-09-01

    The generation of dynamic models of biological processes critically depends on the determination of precise cellular concentrations of biomolecules. Measurements of system-wide absolute protein levels are particularly valuable information in systems biology. Recently, mass spectrometry based proteomics approaches have been developed to estimate protein concentrations on a proteome-wide scale. However, for very complex proteomes, fractionation steps are required, increasing samples number and instrument analysis time. As a result, the number of full proteomes that can be routinely analyzed is limited. Here we combined absolute quantification strategies with the multiplexing capabilities of isobaric tandem mass tags to determine cellular protein abundances in a high throughput and proteome-wide scale even for highly complex biological systems, such as a whole human cell line. We generated two independent data sets to demonstrate the power of the approach regarding sample throughput, dynamic range, quantitative precision and accuracy as well as proteome coverage in comparison to existing mass spectrometry based strategies.

  10. Identification of multidrug resistance protein 1 (MRP1/ABCC1) as a molecular gate for cellular export of cobalamin

    DEFF Research Database (Denmark)

    Beedholm-Ebsen, Rasmus; van de Wetering, Koen; Hardlei, Tore;

    2010-01-01

    transporters by cellular gene silencing showed a role in cellular Cbl efflux of the ATP-binding cassette (ABC)-drug transporter, ABCC1, alias multidrug resistance protein 1 (MRP1), which is present in the basolateral membrane of intestinal epithelium and in other cells. The ability of MRP1 to mediate ATP...... and kidney. In contrast, Cbl accumulates in the terminal part of the intestine of these mice, suggesting a functional malabsorption because of a lower epithelial basolateral Cbl efflux. The identification of this Cbl export mechanism now allows the delineation of a coherent pathway for Cbl trafficking from...

  11. Chemical Genomics Identifies the PERK-Mediated Unfolded Protein Stress Response as a Cellular Target for Influenza Virus Inhibition

    Directory of Open Access Journals (Sweden)

    Sara Landeras-Bueno

    2016-04-01

    Full Text Available Influenza A viruses generate annual epidemics and occasional pandemics of respiratory disease with important consequences for human health and the economy. Therefore, a large effort has been devoted to the development of new anti-influenza virus drugs directed to viral targets, as well as to the identification of cellular targets amenable to anti-influenza virus therapy. Here we have addressed the identification of such potential cellular targets by screening collections of drugs approved for human use. We reasoned that screening with a green fluorescent protein-based recombinant replicon system would identify cellular targets involved in virus transcription/replication and/or gene expression and hence address an early stage of virus infection. By using such a strategy, we identified Montelukast (MK as an inhibitor of virus multiplication. MK inhibited virus gene expression but did not alter viral RNA synthesis in vitro or viral RNA accumulation in vivo. The low selectivity index of MK prevented its use as an antiviral, but it was sufficient to identify a new cellular pathway suitable for anti-influenza virus intervention. By deep sequencing of RNA isolated from mock- and virus-infected human cells, treated with MK or left untreated, we showed that it stimulates the PERK-mediated unfolded protein stress response. The phosphorylation of PERK was partly inhibited in virus-infected cells but stimulated in MK-treated cells. Accordingly, pharmacological inhibition of PERK phosphorylation led to increased viral gene expression, while inhibition of PERK phosphatase reduced viral protein synthesis. These results suggest the PERK-mediated unfolded protein response as a potential cellular target to modulate influenza virus infection.

  12. Autographa californica Multiple Nucleopolyhedrovirus Ac34 Protein Retains Cellular Actin-Related Protein 2/3 Complex in the Nucleus by Subversion of CRM1-Dependent Nuclear Export

    NARCIS (Netherlands)

    Mu, Jingfang; Zhang, Yongli; Hu, Yangyang; Hu, Xue; Zhou, Yuan; Zhao, He; Pei, Rongjuan; Wu, Chunchen; Chen, Jizheng; Zhao, Han; Yang, Kai; Oers, van Monique; Chen, Xinwen; Wang, Yun

    2016-01-01

    Actin, nucleation-promoting factors (NPFs), and the actin-related protein 2/3 complex (Arp2/3) are key elements of the cellular actin polymerization machinery. With nuclear actin polymerization implicated in ever-expanding biological processes and the discovery of the nuclear import mechanisms of ac

  13. Molecular cloning and analysis of functional cDNA and genomic clones encoding bovine cellular retinoic acid-binding protein.

    Science.gov (United States)

    Shubeita, H E; Sambrook, J F; McCormick, A M

    1987-08-01

    A recombinant cDNA clone, pCRABP-HS1, encoding cellular retinoic acid-binding protein was isolated from a bovine adrenal cDNA library. COS-7 cells transfected with pCRABP-HS1 produced a biologically active retinoic acid-binding protein molecule of the expected molecular mass (15.5 kDa). RNA blot hybridization analysis using pCRABP-HS1 as a probe revealed a single 1050-nucleotide mRNA species in bovine adrenal, uterus, and testis, tissues that contain the highest levels of retinoic acid-binding activity. No hybridization was detected in RNA extracted from ovary, spleen, kidney, or liver, which contain relatively low levels of cellular retinoic acid-binding protein activity. Analysis of genomic clones isolated from an EcoRI bovine genomic library demonstrated that the bovine cellular retinoic acid-binding protein gene is composed of four exons and three introns. Two putative promoter sequences were identified in the cloned 5' sequence of the gene.

  14. Delineation of concentration ranges and longitudinal changes of human plasma protein variants.

    Directory of Open Access Journals (Sweden)

    Olgica Trenchevska

    Full Text Available Human protein diversity arises as a result of alternative splicing, single nucleotide polymorphisms (SNPs and posttranslational modifications. Because of these processes, each protein can exists as multiple variants in vivo. Tailored strategies are needed to study these protein variants and understand their role in health and disease. In this work we utilized quantitative mass spectrometric immunoassays to determine the protein variants concentration of beta-2-microglobulin, cystatin C, retinol binding protein, and transthyretin, in a population of 500 healthy individuals. Additionally, we determined the longitudinal concentration changes for the protein variants from four individuals over a 6 month period. Along with the native forms of the four proteins, 13 posttranslationally modified variants and 7 SNP-derived variants were detected and their concentration determined. Correlations of the variants concentration with geographical origin, gender, and age of the individuals were also examined. This work represents an important step toward building a catalog of protein variants concentrations and examining their longitudinal changes.

  15. Protein Corona Influences Cellular Uptake of Gold Nanoparticles by Phagocytic and Nonphagocytic Cells in a Size-Dependent Manner.

    Science.gov (United States)

    Cheng, Xiaju; Tian, Xin; Wu, Anqing; Li, Jianxiang; Tian, Jian; Chong, Yu; Chai, Zhifang; Zhao, Yuliang; Chen, Chunying; Ge, Cuicui

    2015-09-23

    The interaction at nanobio is a critical issue in designing safe nanomaterials for biomedical applications. Recent studies have reported that it is nanoparticle-protein corona rather than bare nanoparticle that determines the nanoparticle-cell interactions, including endocytic pathway and biological responses. Here, we demonstrate the effects of protein corona on cellular uptake of different sized gold nanoparticles in different cell lines. The experimental results show that protein corona significantly decreases the internalization of Au NPs in a particle size- and cell type-dependent manner. Protein corona exhibits much more significant inhibition on the uptake of large-sized Au NPs by phagocytic cell than that of small-sized Au NPs by nonphagocytic cell. The endocytosis experiment indicates that different endocytic pathways might be responsible for the differential roles of protein corona in the interaction of different sized Au NPs with different cell lines. Our findings can provide useful information for rational design of nanomaterials in biomedical application.

  16. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution.

    Science.gov (United States)

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defined mechanisms. Prion protein, for instance, interacts with divalent cations via multiple metal-binding sites and it modulates several metal-dependent physiological functions, such as S-nitrosylation of NMDA receptors. In this work we focused on the effect of prion protein absence on copper and iron metabolism during development and adulthood. In particular, we investigated copper and iron functional values in serum and several organs such as liver, spleen, total brain and isolated hippocampus. Our results show that iron content is diminished in prion protein-null mouse serum, while it accumulates in liver and spleen. Our data suggest that these alterations can be due to impairments in copper-dependent cerulopalsmin activity which is known to affect iron mobilization. In prion protein-null mouse total brain and hippocampus, metal ion content shows a fluctuating trend, suggesting the presence of homeostatic compensatory mechanisms. However, copper and iron functional values are likely altered also in these two organs, as indicated by the modulation of metal-binding protein expression levels. Altogether, these results reveal that the absence of the cellular prion protein impairs copper metabolism and copper-dependent oxidase activity, with ensuing alteration of iron mobilization from cellular storage compartments.

  17. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution

    Science.gov (United States)

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defined mechanisms. Prion protein, for instance, interacts with divalent cations via multiple metal-binding sites and it modulates several metal-dependent physiological functions, such as S-nitrosylation of NMDA receptors. In this work we focused on the effect of prion protein absence on copper and iron metabolism during development and adulthood. In particular, we investigated copper and iron functional values in serum and several organs such as liver, spleen, total brain and isolated hippocampus. Our results show that iron content is diminished in prion protein-null mouse serum, while it accumulates in liver and spleen. Our data suggest that these alterations can be due to impairments in copper-dependent cerulopalsmin activity which is known to affect iron mobilization. In prion protein-null mouse total brain and hippocampus, metal ion content shows a fluctuating trend, suggesting the presence of homeostatic compensatory mechanisms. However, copper and iron functional values are likely altered also in these two organs, as indicated by the modulation of metal-binding protein expression levels. Altogether, these results reveal that the absence of the cellular prion protein impairs copper metabolism and copper-dependent oxidase activity, with ensuing alteration of iron mobilization from cellular storage compartments. PMID:27729845

  18. IN ABSENCE OF THE CELLULAR PRION PROTEIN, ALTERATIONS IN COPPER METABOLISM AND COPPER-DEPENDENT OXIDASE ACTIVITY AFFECT IRON DISTRIBUTION

    OpenAIRE

    Lisa Gasperini; Elisa Meneghetti; Giuseppe Legname; Federico Benetti

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defin...

  19. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution

    OpenAIRE

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defin...

  20. Human cellular protein patterns and their link to genome DNA sequence data: usefulness of two-dimensional gel electrophoresis and microsequencing

    DEFF Research Database (Denmark)

    Celis, J E; Rasmussen, H H; Leffers, H;

    1991-01-01

    Analysis of cellular protein patterns by computer-aided 2-dimensional gel electrophoresis together with recent advances in protein sequence analysis have made possible the establishment of comprehensive 2-dimensional gel protein databases that may link protein and DNA information and that offer a...

  1. Molecular cloning and analysis of functional cDNA and genomic clones encoding bovine cellular retinoic acid-binding protein.

    OpenAIRE

    Shubeita, H E; Sambrook, J F; McCormick, A M

    1987-01-01

    A recombinant cDNA clone, pCRABP-HS1, encoding cellular retinoic acid-binding protein was isolated from a bovine adrenal cDNA library. COS-7 cells transfected with pCRABP-HS1 produced a biologically active retinoic acid-binding protein molecule of the expected molecular mass (15.5 kDa). RNA blot hybridization analysis using pCRABP-HS1 as a probe revealed a single 1050-nucleotide mRNA species in bovine adrenal, uterus, and testis, tissues that contain the highest levels of retinoic acid-bindin...

  2. Traffic jam on the cellular secretory pathway generated by a replication protein from a plant RNA virus.

    Science.gov (United States)

    Hyodo, Kiwamu; Kaido, Masanori; Okuno, Tetsuro

    2014-01-01

    Although positive-strand RNA [(+)RNA] viruses have a limited coding capacity, they can replicate efficiently in host cells because of their ability to use host-derived proteins, membranes, lipids, and metabolites, and to rewire cellular trafficking pathways. Previously, we showed that a plant RNA virus, the Red clover necrotic mosaic virus (RCNMV), hijacked Arf1 and Sar1, which are small GTPases that regulate the biogenesis of COPI and COPII vesicles, respectively, for viral RNA replication. These small GTPases are relocated from appropriate subcellular compartments to the viral RNA replication sites by p27 replication protein, which raises the possibility that RCNMV interferes with the cellular secretory pathway. Here, we examined this possibility by using green fluorescent protein-fused rice SCAMP1 and Arabidopsis LRR84A as secretory pathway marker proteins and showed that p27 inhibited the trafficking of these proteins. RCNMV-mediated inhibition of the host secretion pathway and its possible impact on plant-virus interaction are discussed.

  3. Protein oxidation and aggregation in UVA-irradiated Escherichia coli cells as signs of accelerated cellular senescence.

    Science.gov (United States)

    Bosshard, Franziska; Riedel, Kathrin; Schneider, Thomas; Geiser, Carina; Bucheli, Margarete; Egli, Thomas

    2010-11-01

    Solar disinfection (SODIS) is a simple drinking water treatment method that improves microbiological water quality where other means are unavailable. It makes use of the deleterious effect of solar irradiation on pathogenic microbes and viruses. A positive impact on health has been documented in several epidemiological studies. However, the molecular mechanisms damaging cells during this simple treatment are not yet fully understood. Here we show that protein damage is crucial in the process of inactivation by sunlight. Protein damages in UVA-irradiated Escherichia coli cells have been evaluated by an immunoblot method for carbonylated proteins and an aggregation assay based on semi-quantitative proteomics. A wide spectrum of structural and enzymatic proteins within the cell is affected by carbonylation and aggregation. Vital cellular functions like the transcription and translation apparatus, transport systems, amino acid synthesis and degradation, respiration, ATP synthesis, glycolysis, the TCA cycle, chaperone functions and catalase are targeted by UVA irradiation. The protein damage pattern caused by SODIS strongly resembles the pattern caused by reactive oxygen stress. Hence, sunlight probably accelerates cellular senescence and leads to the inactivation and finally death of UVA-irradiated cells.

  4. Inhibition of cellular protein secretion by norwalk virus nonstructural protein p22 requires a mimic of an endoplasmic reticulum export signal.

    Directory of Open Access Journals (Sweden)

    Tyler M Sharp

    Full Text Available Protein trafficking between the endoplasmic reticulum (ER and Golgi apparatus is central to cellular homeostasis. ER export signals are utilized by a subset of proteins to rapidly exit the ER by direct uptake into COPII vesicles for transport to the Golgi. Norwalk virus nonstructural protein p22 contains a YXΦESDG motif that mimics a di-acidic ER export signal in both sequence and function. However, unlike normal ER export signals, the ER export signal mimic of p22 is necessary for apparent inhibition of normal COPII vesicle trafficking, which leads to Golgi disassembly and antagonism of Golgi-dependent cellular protein secretion. This is the first reported function for p22. Disassembly of the Golgi apparatus was also observed in cells replicating Norwalk virus, which may contribute to pathogenesis by interfering with cellular processes that are dependent on an intact secretory pathway. These results indicate that the ER export signal mimic is critical to the antagonistic function of p22, shown herein to be a novel antagonist of ER/Golgi trafficking. This unique and well-conserved human norovirus motif is therefore an appealing target for antiviral drug development.

  5. Overproduction of a Model Sec- and Tat-Dependent Secretory Protein Elicits Different Cellular Responses in Streptomyces lividans.

    Science.gov (United States)

    Gullón, Sonia; Marín, Silvia; Mellado, Rafael P

    2015-01-01

    Streptomyces lividans is considered an efficient host for the secretory production of homologous and heterologous proteins. To identify possible bottlenecks in the protein production process, a comparative transcriptomic approach was adopted to study cellular responses during the overproduction of a Sec-dependent model protein (alpha-amylase) and a Tat-dependent model protein (agarase) in Streptomyces lividans. The overproduction of the model secretory proteins via the Sec or the Tat route in S. lividans does elicit a different major cell response in the bacterium. The stringent response is a bacterial response to nutrients' depletion, which naturally occurs at late times of the bacterial cell growth. While the induction of the stringent response at the exponential phase of growth may limit overall productivity in the case of the Tat route, the induction of that response does not take place in the case of the Sec route, which comparatively is an advantage in secretory protein production processes. Hence, this study identifies a potential major drawback in the secretory protein production process depending on the secretory route, and provides clues to improving S. lividans as a protein production host.

  6. Overproduction of a Model Sec- and Tat-Dependent Secretory Protein Elicits Different Cellular Responses in Streptomyces lividans

    Science.gov (United States)

    Gullón, Sonia; Marín, Silvia; Mellado, Rafael P.

    2015-01-01

    Streptomyces lividans is considered an efficient host for the secretory production of homologous and heterologous proteins. To identify possible bottlenecks in the protein production process, a comparative transcriptomic approach was adopted to study cellular responses during the overproduction of a Sec-dependent model protein (alpha-amylase) and a Tat-dependent model protein (agarase) in Streptomyces lividans. The overproduction of the model secretory proteins via the Sec or the Tat route in S. lividans does elicit a different major cell response in the bacterium. The stringent response is a bacterial response to nutrients’ depletion, which naturally occurs at late times of the bacterial cell growth. While the induction of the stringent response at the exponential phase of growth may limit overall productivity in the case of the Tat route, the induction of that response does not take place in the case of the Sec route, which comparatively is an advantage in secretory protein production processes. Hence, this study identifies a potential major drawback in the secretory protein production process depending on the secretory route, and provides clues to improving S. lividans as a protein production host. PMID:26200356

  7. Zea mays Taxilin protein negatively regulates opaque-2 transcriptional activity by causing a change in its sub-cellular distribution.

    Directory of Open Access Journals (Sweden)

    Nan Zhang

    Full Text Available Zea mays (maize Opaque-2 (ZmO2 protein is an important bZIP transcription factor that regulates the expression of major storage proteins (22-kD zeins and other important genes during maize seed development. ZmO2 is subject to functional regulation through protein-protein interactions. To unveil the potential regulatory network associated with ZmO2, a protein-protein interaction study was carried out using the truncated version of ZmO2 (O2-2 as bait in a yeast two-hybrid screen with a maize seed cDNA library. A protein with homology to Taxilin was found to have stable interaction with ZmO2 in yeast and was designated as ZmTaxilin. Sequence analysis indicated that ZmTaxilin has a long coiled-coil domain containing three conserved zipper motifs. Each of the three zipper motifs is individually able to interact with ZmO2 in yeast. A GST pull-down assay demonstrated the interaction between GST-fused ZmTaxilin and ZmO2 extracted from developing maize seeds. Using onion epidermal cells as in vivo assay system, we found that ZmTaxilin could change the sub-cellular distribution of ZmO2. We also demonstrated that this change significantly repressed the transcriptional activity of ZmO2 on the 22-kD zein promoter. Our study suggests that a Taxilin-mediated change in sub-cellular distribution of ZmO2 may have important functional consequences for ZmO2 activity.

  8. Clusterin: full-length protein and one of its chains show opposing effects on cellular lipid accumulation

    Science.gov (United States)

    Matukumalli, Suvarsha Rao; Tangirala, Ramakrishna; Rao, C. M.

    2017-01-01

    Proteins, made up of either single or multiple chains, are designed to carry out specific biological functions. We found an interesting example of a two-chain protein where administration of one of its chains leads to a diametrically opposite outcome than that reported for the full-length protein. Clusterin is a highly glycosylated protein consisting of two chains, α- and β-clusterin. We have investigated the conformational features, cellular localization, lipid accumulation, in vivo effects and histological changes upon administration of recombinant individual chains of clusterin. We demonstrate that recombinant α- and β-chains exhibit structural and functional differences and differ in their sub-cellular localization. Full-length clusterin is known to lower lipid levels. In contrast, we find that β-chain-treated cells accumulate 2-fold more lipid than controls. Interestingly, α-chain-treated cells do not show such increase. Rabbits injected with β-chain, but not α-chain, show ~40% increase in weight, with adipocyte hypertrophy, liver and kidney steatosis. Many, sometimes contrasting, roles are ascribed to clusterin in obesity, metabolic syndrome and related conditions. Our findings of differential localization and activities of individual chains of clusterin should help in understanding better the roles of clusterin in metabolism. PMID:28120874

  9. Adult neurogenesis and the unfolded protein response; new cellular and molecular avenues in sleep research

    NARCIS (Netherlands)

    Lucassen, P.J.; Scheper, W.; van Someren, E.J.W.

    2009-01-01

    Two recent publications in this journal highlight the impact of new developments for our understanding of the mechanisms underlying the consequences of sleep disturbance and sleep loss. Meerlo et al. discuss effects of sleep disturbance at the cellular level, focusing mainly on adult neurogenesis an

  10. 肾移植后早期监测外周血视黄醇结合蛋白4的临床意义%Continuous monitoring of peripheral blood retinol blinding protein-4 in the early stage after renal transplantation

    Institute of Scientific and Technical Information of China (English)

    周宇; 郑鳕洋; 陆瀚澜; 陈瑜; 傅尚希; 王立明

    2015-01-01

    BACKGROUND:Retinol binding protein-4 is a most sensitive biomarker for loss of function of the human proximal renal tubule, which is applied in the early detection of acute kidney injury. It is speculated that retinol binding protein-4 may be associated with acute rejection and delayed graft function after renal transplantation. OBJECTIVE: To investigate the correlation of peripheral blood retinol binding protein-4 and renal alograft function in the early stage after renal transplantation. METHODS:The venous blood samples of renal transplantation recipients were continuously colected for detection. As a retrospective nested case-control study, 20 cases of clinical diagnosed acute rejection were selected as acute rejection group. Another 20 cases of delayed graft function and 20 cases with normal graft function were randomly selected according to the ratio of 1:1:1 and taken as delayed graft function group and control group, respectively. Retinol binding protein-4 level was detected by the immune turbidimetric method, and meanwhile, the serum creatinine and blood urea nitrogen levels were dynamicaly examined by the sarcosine oxidase method. Then, al the data were comparatively analyzed at vertical and horizontal levels. RESULTS AND CONCLUSION:Compared with the control group, retinol binding protein-4 and serum creatinine levels in the acute rejection group and the delayed graft function group were significantly higher (P < 0.05). Retinol binding protein-4 and serum creatinine levels in the acute rejection group were significantly different between the rejection and non-rejection periods (P < 0.01). Similarly, these two indicators in the delayed graft function group were significantly different between the normal and abnormal renal function periods (P < 0.05). Retinol binding protein-4 levels were positively correlated with serum creatinine and blood urea nitrogen levels. Both in the acute rejection group and delayed graft function group, retinol binding protein-4

  11. What makes protein indigestible from tissue-related, cellular, and molecular aspects?

    NARCIS (Netherlands)

    Becker, P.M.; Yu, P.Q.

    2013-01-01

    This paper gives an insight into key factors, which impair enzymatic protein digestion. By nature, some proteins in raw products are already poorly digestible because of structural peculiarities, or due to their occurrence in plant cytoplasmic organelles or in cell membranes. In plant-based protein,

  12. Topology and cellular localization of the small hydrophobic protein of avian metapneumovirus

    Science.gov (United States)

    The small hydrophobic protein (SH) is a type II integral membrane protein that is packaged into virions and is only present in certain paramyxoviruses including metapneumovirus. In addition to a highly divergent primary sequence, SH proteins vary significantly in size among the different viruses. Hu...

  13. The Protein Corona of Plant Virus Nanoparticles Influences their Dispersion Properties, Cellular Interactions, and In Vivo Fates.

    Science.gov (United States)

    Pitek, Andrzej S; Wen, Amy M; Shukla, Sourabh; Steinmetz, Nicole F

    2016-04-06

    Biomolecules in bodily fluids such as plasma can adsorb to the surface of nanoparticles and influence their biological properties. This phenomenon, known as the protein corona, is well established in the field of synthetic nanotechnology but has not been described in the context of plant virus nanoparticles (VNPs). The interaction between VNPs derived from Tobacco mosaic virus (TMV) and plasma proteins is investigated, and it is found that the VNP protein corona is significantly less abundant compared to the corona of synthetic particles. The formed corona is dominated by complement proteins and immunoglobulins, the binding of which can be reduced by PEGylating the VNP surface. The impact of the VNP protein corona on molecular recognition and cell targeting in the context of cancer and thrombosis is investigated. A library of functionalized TMV rods with polyethylene glycol (PEG) and peptide ligands targeting integrins or fibrin(ogen) show different dispersion properties, cellular interactions, and in vivo fates depending on the properties of the protein corona, influencing target specificity, and non-specific scavenging by macrophages. Our results provide insight into the in vivo properties of VNPs and suggest that the protein corona effect should be considered during the development of efficacious, targeted VNP formulations.

  14. Identification of cellular proteins that interact with Newcastle Disease Virus and human Respiratory Syncytial Virus by a two-dimensional virus overlay protein binding assay (VOPBA).

    Science.gov (United States)

    Holguera, Javier; Villar, Enrique; Muñoz-Barroso, Isabel

    2014-10-13

    Although it is well documented that the initial attachment receptors for Newcastle Disease Virus (NDV) and Respiratory Syncytial Virus (RSV) are sialic acid-containing molecules and glycosaminoglycans respectively, the exact nature of the receptors for both viruses remains to be deciphered. Moreover, additional molecules at the host cell surface might be involved in the entry mechanism. With the aim of identifying the cellular proteins that interact with NDV and RSV at the cell surface, we performed a virus overlay protein binding assay (VOPBA). Cell membrane lysates were separated by two dimensional (2D) gel electrophoresis and electrotransferred to PVDF membranes, after which they were probed with high viral concentrations. NDV interacted with a Protein Disulfide Isomerase from chicken fibroblasts. In the case of RSV, we detected 15 reactive spots, which were identified as six different proteins, of which nucleolin was outstanding. We discuss the possible role of PDI and nucleolin in NDV and RSV entry, respectively.

  15. Involvement of the interferon-regulated antiviral proteins PKR and RNase L in reovirus-induced shutoff of cellular translation.

    Science.gov (United States)

    Smith, Jennifer A; Schmechel, Stephen C; Williams, Bryan R G; Silverman, Robert H; Schiff, Leslie A

    2005-02-01

    Cellular translation is inhibited following infection with most strains of reovirus, but the mechanisms responsible for this phenomenon remain to be elucidated. The extent of host shutoff varies in a strain-dependent manner; infection with the majority of strains leads to strong host shutoff, while infection with strain Dearing results in minimal inhibition of cellular translation. A genetic study with reassortant viruses and subsequent biochemical analyses led to the hypothesis that the interferon-induced, double-stranded RNA-activated protein kinase, PKR, is responsible for reovirus-induced host shutoff. To directly determine whether PKR is responsible for reovirus-induced host shutoff, we used a panel of reovirus strains and mouse embryo fibroblasts derived from knockout mice. This approach revealed that PKR contributes to but is not wholly responsible for reovirus-induced host shutoff. Studies with cells lacking RNase L, the endoribonuclease component of the interferon-regulated 2',5'-oligoadenylate synthetase-RNase L system, demonstrated that RNase L also down-regulates cellular protein synthesis in reovirus-infected cells. In many viral systems, PKR and RNase L have well-characterized antiviral functions. An analysis of reovirus replication in cells lacking these molecules indicated that, while they contributed to host shutoff, neither PKR nor RNase L exerted an antiviral effect on reovirus growth. In fact, some strains of reovirus replicated more efficiently in the presence of PKR and RNase L than in their absence. Data presented in this report illustrate that the inhibition of cellular translation following reovirus infection is complex and involves multiple interferon-regulated gene products. In addition, our results suggest that reovirus has evolved effective mechanisms to avoid the actions of the interferon-stimulated antiviral pathways that include PKR and RNase L and may even benefit from their expression.

  16. Involvement of the iron regulatory protein from Eisenia andrei earthworms in the regulation of cellular iron homeostasis.

    Directory of Open Access Journals (Sweden)

    Petra Procházková

    Full Text Available Iron homeostasis in cells is regulated by iron regulatory proteins (IRPs that exist in different organisms. IRPs are cytosolic proteins that bind to iron-responsive elements (IREs of the 5'- or 3'-untranslated regions (UTR of mRNAs that encode many proteins involved in iron metabolism. In this study, we have cloned and described a new regulatory protein belonging to the family of IRPs from the earthworm Eisenia andrei (EaIRP. The earthworm IRE site in 5'-UTR of ferritin mRNA most likely folds into a secondary structure that differs from the conventional IRE structures of ferritin due to the absence of a typically unpaired cytosine that participates in protein binding. Prepared recombinant EaIRP and proteins from mammalian liver extracts are able to bind both mammalian and Eisenia IRE structures of ferritin mRNA, although the affinity of the rEaIRP/Eisenia IRE structure is rather low. This result suggests the possible contribution of a conventional IRE structure. When IRP is supplemented with a Fe-S cluster, it can function as a cytosolic aconitase. Cellular cytosolic and mitochondrial fractions, as well as recombinant EaIRP, exhibit aconitase activity that can be abolished by the action of oxygen radicals. The highest expression of EaIRP was detected in parts of the digestive tract. We can assume that earthworms may possess an IRE/IRP regulatory network as a potential mechanism for maintaining cellular iron homeostasis, although the aconitase function of EaIRP is most likely more relevant.

  17. Potential role of DNA-dependent protein kinase in cellular resistance to ionizing radiation

    Institute of Scientific and Technical Information of China (English)

    LI Ning; ZHANG Hong; WANG Yanling; WANG Xiaohu; HAO Jifang

    2009-01-01

    In this paper, we study the ability of DNA-PK-deficient (M059J) and -proficient (M059K) cells to undergo the rate of cellular proliferation, cell cycle distribution and apoptosis after 10 Gy X-ray irradiation, and the role of DNA-PK in radiosensitivity. The results showed that M059J cells exhibited hyper-radiosensitivity compared with M059K cells. A strong G2 phase arrest was observed in M059J cells post irradiation. Significant accumulation in the G2 phase in M059J cells was accompanied by apoptosis at 12 h. Altogether, the data suggested that DNA-PK may have two roles in mammalian cells after DNA damage, a role in DNA DSB repair and a second role in DNA-damaged cells to traverse a G2 checkpoint, by which DNA-PK may affect cellular sensitivity to ionizing radiation.

  18. Recent progress in design of protein-based fluorescent biosensors and their cellular applications.

    Science.gov (United States)

    Tamura, Tomonori; Hamachi, Itaru

    2014-12-19

    Protein-based fluorescent biosensors have emerged as key bioanalytical tools to visualize and quantify a wide range of biological substances and events in vitro, in cells, and even in vivo. On the basis of the construction method, the protein-based fluorescent biosensors can be principally classified into two classes: (1) genetically encoded fluorescent biosensors harnessing fluorescent proteins (FPs) and (2) semisynthetic biosensors comprised of protein scaffolds and synthetic fluorophores. Recent advances in protein engineering and chemical biology not only allowed the further optimization of conventional biosensors but also facilitated the creation of novel biosensors based on unique strategies. In this review, we survey the recent studies in the development and improvement of protein-based fluorescent biosensors and highlight the successful applications to live cell and in vivo imaging. Furthermore, we provide perspectives on possible future directions of the technique.

  19. Protein kinase CK2 and its role in cellular proliferation, development and pathology

    DEFF Research Database (Denmark)

    Guerra, B; Issinger, O G

    1999-01-01

    Protein kinase CK2 is a pleiotropic, ubiquitous and constitutively active protein kinase that can use both ATP and GTP as phosphoryl donors with specificity for serine/threonine residues in the vicinity of acidic amino acids. Recent results show that the enzyme is involved in transcription...... conserved throughout evolution. Furthermore the existence of different CK2beta-related proteins together with the observation of deregulated CK2beta levels in tumor cells and the reported association of CK2beta protein with key proteins in signal transduction, e.g. A-Raf, Mos, pg90rsk etc. are suggestive...... for an additional physiological role of CK2beta protein beside being the regulatory compound in the tetrameric holoenzyme....

  20. Progress in studies on the DEK protein and its involvement in cellular apoptosis

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    DEK protein is an ubiquitous phosphorylated nuclear protein.Specific binding of DEK to DNA could change the topology of DNA and then affect the gene activity of the underlying DNA sequences.It is speculated that there might be some potential relationship between the stress reaction of cells and DEK proteins.The phosphorylation status of DEK protein is altered during death-receptor-mediated cell apoptosis.Both phosphorylation and poly(ADP-ribosyl)ation could promote the release of DEK from apoptotic nuclei to extracellular environment,and in this case DEK becomes a potential autoantigen of some autoimmune diseases.The available evidence powerfully suggests that DEK protein is closely relevant to apoptosis.The overexpression of DEK protein has dual function in cell apoptosis,in terms of inhibiting or triggering cell apoptosis.

  1. Progress in studies on the DEK protein and its involvement in cellular apoptosis

    Institute of Scientific and Technical Information of China (English)

    HUA Ying; HU HongGang; PENG XiangLei

    2009-01-01

    DEK protein is an ubiquitous phosphorylated nuclear protein. Specific binding of DEK to DNA could change the topology of DNA and then affect the gene activity of the underlying DNA sequences. It is speculated that there might be some potential relationship between the stress reaction of cells and DEK proteins. The phosphorylation status of DEK protein is altered during death-receptor-mediated cell apoptosis. Both phosphorylation and poly(ADP-ribosyl)aUon could promote the release of DEK from apoptotic nuclei to extracellular environment, and in this case DEK becomes a potential autoantigen of some autoimmune diseases. The available evidence powerfully suggests that DEK protein is closely relevant to apoptosis. The overexpression of DEK protein has dual function in cell apoptosis, in terms of inhibiting or triggering cell apoptosis.

  2. Cellular fatty acid composition, protein profile and antimicrobial activity of Bacillus sp., isolated from fish gut

    Institute of Scientific and Technical Information of China (English)

    Pushparaj Sujith; Baskaran Rohini; Singaram Jayalakshmi

    2014-01-01

    Objective: To purify and partially characterize the antimicrobial compounds from bacteriaBacillus sp., isolated from fish gut. Methods: Protein and fatty acids were isolated from the bacteria and checked for the presence of antibacterial activity. Protein has been purified to apparent homogeneity from the supernatants of culture by means of ammonium sulphate precipitation followed by dialysis. Fourier transform infrared spectroscopy analyses were performed for proteins to identify the functional groups.Results:sulfate polyacrylamide gel electrophoresis. Fatty acids were extracted and subjected to gas chromatographic analysis.Conclusions:Protein showed an apparent molecular mass 56, 47 and 39 kDa on sodium dodecyl acids and proteins which holds promise for the development of new drugs. The antimicrobial activity of the bacteria might be due to the presence of fatty acids and proteins which holds promise for the development of new drugs.

  3. Distinct cellular and subcellular distributions of G protein-coupled receptor kinase and arrestin isoforms in the striatum.

    Directory of Open Access Journals (Sweden)

    Evgeny Bychkov

    Full Text Available G protein-coupled receptor kinases (GRKs and arrestins mediate desensitization of G protein-coupled receptors (GPCR. Arrestins also mediate G protein-independent signaling via GPCRs. Since GRK and arrestins demonstrate no strict receptor specificity, their functions in the brain may depend on their cellular complement, expression level, and subcellular targeting. However, cellular expression and subcellular distribution of GRKs and arrestins in the brain is largely unknown. We show that GRK isoforms GRK2 and GRK5 are similarly expressed in direct and indirect pathway neurons in the rat striatum. Arrestin-2 and arrestin-3 are also expressed in neurons of both pathways. Cholinergic interneurons are enriched in GRK2, arrestin-3, and GRK5. Parvalbumin-positive interneurons express more of GRK2 and less of arrestin-2 than medium spiny neurons. The GRK5 subcellular distribution in the human striatal neurons is altered by its phosphorylation: unphosphorylated enzyme preferentially localizes to synaptic membranes, whereas phosphorylated GRK5 is found in plasma membrane and cytosolic fractions. Both GRK isoforms are abundant in the nucleus of human striatal neurons, whereas the proportion of both arrestins in the nucleus was equally low. However, overall higher expression of arrestin-2 yields high enough concentration in the nucleus to mediate nuclear functions. These data suggest cell type- and subcellular compartment-dependent differences in GRK/arrestin-mediated desensitization and signaling.

  4. Systematic Characterisation of Cellular Localisation and Expression Profiles of Proteins Containing MHC Ligands

    DEFF Research Database (Denmark)

    Juncker, Agnieszka; Larsen, Mette Voldby; Weinhold, Nils

    2009-01-01

    that most proteins containing MHC class I ligands were localised to the intracellular parts of the cell including the cytoplasm and nucleus. MHC class II ligand donors were, on the other hand, mostly membrane proteins. Conclusions/Significance: The results contribute to the ongoing debate concerning...... the nature of MHC ligand-containing proteins and can be used to extend the existing methods for MHC ligand predictions by including the source protein's localisation and expression profile. Improving the current methods is important in the growing quest for epitopes that can be used for vaccine or diagnostic...

  5. Cytoplasmic illuminations: in planta targeting of fluorescent proteins to cellular organelles.

    Science.gov (United States)

    Hawes, C; Saint-Jore, C M; Brandizzi, F; Zheng, H; Andreeva, A V; Boevink, P

    2001-01-01

    Use of the jellyfish green-fluorescent protein as an in vivo reporter is in the process of revolutionising plant cell biology. By fusing the protein to specific targeting peptides or to sequences of complete proteins, it is now possible to observe the location, structure, and dynamics of a number of intracellular organelles over extended periods of time. In this review we discuss the most recent developments and unexpected results originating from the targeting of this unique protein and its derivatives to elements of the cytoskeleton and to membrane-bounded organelles in a range of plant cell types.

  6. Degradation of Human PDZ-Proteins by Human Alphapapillomaviruses Represents an Evolutionary Adaptation to a Novel Cellular Niche

    Science.gov (United States)

    Van Doorslaer, Koenraad; DeSalle, Rob; Einstein, Mark H.; Burk, Robert D.

    2015-01-01

    In order to complete their life cycle, papillomaviruses have evolved to manipulate a plethora of cellular pathways. The products of the human Alphapapillomavirus E6 proteins specifically interact with and target PDZ containing proteins for degradation. This viral phenotype has been suggested to play a role in viral oncogenesis. To analyze the association of HPV E6 mediated PDZ-protein degradation with cervical oncogenesis, a high-throughput cell culture assay was developed. Degradation of an epitope tagged human MAGI1 isoform was visualized by immunoblot. The correlation between HPV E6-induced degradation of hMAGI1 and epidemiologically determined HPV oncogenicity was evaluated using a Bayesian approach within a phylogenetic context. All tested oncogenic types degraded the PDZ-containing protein hMAGI1d; however, E6 proteins isolated from several related albeit non-oncogenic viral types were equally efficient at degrading hMAGI1. The relationship between both traits (oncogenicity and PDZ degradation potential) is best explained by a model in which the potential to degrade PDZ proteins was acquired prior to the oncogenic phenotype. This analysis provides evidence that the ancestor of both oncogenic and non-oncogenic HPVs acquired the potential to degrade human PDZ-containing proteins. This suggests that HPV E6 directed degradation of PDZ-proteins represents an ancient ecological niche adaptation. Phylogenetic modeling indicates that this phenotype is not specifically correlated with oncogenic risk, but may act as an enabling phenotype. The role of PDZ protein degradation in HPV fitness and oncogenesis needs to be interpreted in the context of Alphapapillomavirus evolution. PMID:26086730

  7. Degradation of Human PDZ-Proteins by Human Alphapapillomaviruses Represents an Evolutionary Adaptation to a Novel Cellular Niche.

    Directory of Open Access Journals (Sweden)

    Koenraad Van Doorslaer

    2015-06-01

    Full Text Available In order to complete their life cycle, papillomaviruses have evolved to manipulate a plethora of cellular pathways. The products of the human Alphapapillomavirus E6 proteins specifically interact with and target PDZ containing proteins for degradation. This viral phenotype has been suggested to play a role in viral oncogenesis. To analyze the association of HPV E6 mediated PDZ-protein degradation with cervical oncogenesis, a high-throughput cell culture assay was developed. Degradation of an epitope tagged human MAGI1 isoform was visualized by immunoblot. The correlation between HPV E6-induced degradation of hMAGI1 and epidemiologically determined HPV oncogenicity was evaluated using a Bayesian approach within a phylogenetic context. All tested oncogenic types degraded the PDZ-containing protein hMAGI1d; however, E6 proteins isolated from several related albeit non-oncogenic viral types were equally efficient at degrading hMAGI1. The relationship between both traits (oncogenicity and PDZ degradation potential is best explained by a model in which the potential to degrade PDZ proteins was acquired prior to the oncogenic phenotype. This analysis provides evidence that the ancestor of both oncogenic and non-oncogenic HPVs acquired the potential to degrade human PDZ-containing proteins. This suggests that HPV E6 directed degradation of PDZ-proteins represents an ancient ecological niche adaptation. Phylogenetic modeling indicates that this phenotype is not specifically correlated with oncogenic risk, but may act as an enabling phenotype. The role of PDZ protein degradation in HPV fitness and oncogenesis needs to be interpreted in the context of Alphapapillomavirus evolution.

  8. MNF, an ankyrin repeat protein of myxoma virus, is part of a native cellular SCF complex during viral infection.

    Science.gov (United States)

    Blanié, Sophie; Gelfi, Jacqueline; Bertagnoli, Stéphane; Camus-Bouclainville, Christelle

    2010-03-08

    Myxoma virus (MYXV), a member of the Poxviridae family, is the agent responsible for myxomatosis, a fatal disease in the European rabbit (Oryctolagus cuniculus). Like all poxviruses, MYXV is known for encoding multiple proteins that regulate cellular signaling pathways. Among them, four proteins share the same ANK/PRANC structure: M148R, M149R, MNF (Myxoma Nuclear factor) and M-T5, all of them described as virulence factors. This family of poxvirus proteins, recently identified, has drawn considerable attention for its potential role in modulating the host ubiquitin-proteasome system during viral infection. To date, many members of this novel protein family have been shown to interact with SCF components, in vitro. Here, we focus on MNF gene, which has been shown to express a nuclear protein presenting nine ANK repeats, one of which has been identified as a nuclear localization signal. In transfection, MNF has been shown to colocalise with the transcription factor NF-kappaB in the nucleus of TNFalpha-stimulated cells. Functionally, MNF is a critical virulence factor since its deletion generates an almost apathogenic virus. In this study, to pursue the investigation of proteins interacting with MNF and of its mechanism of action, we engineered a recombinant MYXV expressing a GFP-linked MNF under the control of MNF native promoter. Infection of rabbits with MYXV-GFPMNF recombinant virus provided the evidence that the GFP fusion does not disturb the main function of MNF. Hence, cells were infected with MYXV-GFPMNF and immunoprecipitation of the GFPMNF fusion protein was performed to identify MNF's partners. For the first time, endogenous components of SCF (Cullin-1 and Skp1) were co-precipitated with an ANK myxoma virus protein, expressed in an infectious context, and without over-expression of any protein.

  9. MNF, an ankyrin repeat protein of myxoma virus, is part of a native cellular SCF complex during viral infection

    Directory of Open Access Journals (Sweden)

    Gelfi Jacqueline

    2010-03-01

    Full Text Available Abstract Myxoma virus (MYXV, a member of the Poxviridae family, is the agent responsible for myxomatosis, a fatal disease in the European rabbit (Oryctolagus cuniculus. Like all poxviruses, MYXV is known for encoding multiple proteins that regulate cellular signaling pathways. Among them, four proteins share the same ANK/PRANC structure: M148R, M149R, MNF (Myxoma Nuclear factor and M-T5, all of them described as virulence factors. This family of poxvirus proteins, recently identified, has drawn considerable attention for its potential role in modulating the host ubiquitin-proteasome system during viral infection. To date, many members of this novel protein family have been shown to interact with SCF components, in vitro. Here, we focus on MNF gene, which has been shown to express a nuclear protein presenting nine ANK repeats, one of which has been identified as a nuclear localization signal. In transfection, MNF has been shown to colocalise with the transcription factor NF-κB in the nucleus of TNFα-stimulated cells. Functionally, MNF is a critical virulence factor since its deletion generates an almost apathogenic virus. In this study, to pursue the investigation of proteins interacting with MNF and of its mechanism of action, we engineered a recombinant MYXV expressing a GFP-linked MNF under the control of MNF native promoter. Infection of rabbits with MYXV-GFPMNF recombinant virus provided the evidence that the GFP fusion does not disturb the main function of MNF. Hence, cells were infected with MYXV-GFPMNF and immunoprecipitation of the GFPMNF fusion protein was performed to identify MNF's partners. For the first time, endogenous components of SCF (Cullin-1 and Skp1 were co-precipitated with an ANK myxoma virus protein, expressed in an infectious context, and without over-expression of any protein.

  10. Degradation of Human PDZ-Proteins by Human Alphapapillomaviruses Represents an Evolutionary Adaptation to a Novel Cellular Niche.

    Science.gov (United States)

    Van Doorslaer, Koenraad; DeSalle, Rob; Einstein, Mark H; Burk, Robert D

    2015-06-01

    In order to complete their life cycle, papillomaviruses have evolved to manipulate a plethora of cellular pathways. The products of the human Alphapapillomavirus E6 proteins specifically interact with and target PDZ containing proteins for degradation. This viral phenotype has been suggested to play a role in viral oncogenesis. To analyze the association of HPV E6 mediated PDZ-protein degradation with cervical oncogenesis, a high-throughput cell culture assay was developed. Degradation of an epitope tagged human MAGI1 isoform was visualized by immunoblot. The correlation between HPV E6-induced degradation of hMAGI1 and epidemiologically determined HPV oncogenicity was evaluated using a Bayesian approach within a phylogenetic context. All tested oncogenic types degraded the PDZ-containing protein hMAGI1d; however, E6 proteins isolated from several related albeit non-oncogenic viral types were equally efficient at degrading hMAGI1. The relationship between both traits (oncogenicity and PDZ degradation potential) is best explained by a model in which the potential to degrade PDZ proteins was acquired prior to the oncogenic phenotype. This analysis provides evidence that the ancestor of both oncogenic and non-oncogenic HPVs acquired the potential to degrade human PDZ-containing proteins. This suggests that HPV E6 directed degradation of PDZ-proteins represents an ancient ecological niche adaptation. Phylogenetic modeling indicates that this phenotype is not specifically correlated with oncogenic risk, but may act as an enabling phenotype. The role of PDZ protein degradation in HPV fitness and oncogenesis needs to be interpreted in the context of Alphapapillomavirus evolution.

  11. Avian reovirus nonstructural protein p17-induced G(2)/M cell cycle arrest and host cellular protein translation shutoff involve activation of p53-dependent pathways.

    Science.gov (United States)

    Chulu, Julius L C; Huang, Wei R; Wang, L; Shih, Wen L; Liu, Hung J

    2010-08-01

    The effects of avian reovirus (ARV) p17 protein on cell cycle progression and host cellular protein translation were studied. ARV infection and ARV p17 transfection resulted in the accumulation of infected and/or transfected cells in the G(2)/M phase of the cell cycle. The accumulation of cells in the G(2)/M phase was accompanied by upregulation and phosphorylation of the G(2)/M-phase proteins ATM, p53, p21(cip1/waf1), Cdc2, cyclin B1, Chk1, Chk2, and Cdc25C, suggesting that p17 induces a G(2)/M cell cycle arrest through activation of the ATM/p53/p21(cip1/waf1)/Cdc2/cyclin B1 and ATM/Chk1/Chk2/Cdc25C pathways. The G(2)/M cell cycle arrest resulted in increased virus replication. In the present study, we also provide evidence demonstrating that p17 protein is responsible for ARV-induced host cellular protein translation shutoff. Increased phosphorylation levels of the eukaryotic translation elongation factor 2 (eEF2) and initiation factor eIF2alpha and reduced phosphorylation levels of the eukaryotic translation initiation factors eIF4E, eIF4B, and eIF4G, as well as 4E-BP1 and Mnk-1 in p17-transfected cells, demonstrated that ARV p17 suppresses translation initiation factors and translation elongation factors to induce host cellular protein translation shutoff. Inhibition of mTOR by rapamycin resulted in a decrease in the levels of phosphorylated 4E-BP1, eIF4B, and eIF4G and an increase in the levels eEF2 but did not affect ARV replication, suggesting that ARV replication was not hindered by inhibition of cap-dependent translation. Taken together, our data indicate that ARV p17-induced G(2)/M arrest and host cellular translation shutoff resulted in increased ARV replication.

  12. Scaffolds, levers, rods and springs: diverse cellular functions of long coiled-coil proteins.

    Science.gov (United States)

    Rose, A; Meier, I

    2004-08-01

    Long alpha-helical coiled-coil proteins are involved in a variety of organizational and regulatory processes in eukaryotic cells. They provide cables and networks in the cyto- and nucleoskeleton, molecular scaffolds that organize membrane systems, motors, levers, rotating arms and possibly springs. A growing number of human diseases are found to be caused by mutations in long coiled-coil proteins. This review summarizes our current understanding of the multifaceted group of long coiled-coil proteins in the cytoskeleton, nucleus, Golgi and cell division apparatus. The biophysical features of coiled-coil domains provide first clues toward their contribution to the diverse protein functions and promise potential future applications in the area of nanotechnology. Combining the power of fully sequenced genomes and structure prediction algorithms, it is now possible to comprehensively summarize and compare the complete inventory of coiled-coil proteins of different organisms.

  13. Cellular fatty acid composition, protein profile and antimicrobial activity of Bacillus sp., isolated from fish gut

    Directory of Open Access Journals (Sweden)

    Pushparaj Sujith

    2014-01-01

    Full Text Available Objective: To purify and partially characterize the antimicrobial compounds from bacteria Bacillus sp., isolated from fish gut. Methods: Protein and fatty acids were isolated from the bacteria and checked for the presence of antibacterial activity. Protein has been purified to apparent homogeneity from the supernatants of culture by means of ammonium sulphate precipitation followed by dialysis. Fourier transform infrared spectroscopy analyses were performed for proteins to identify the functional groups. Results: Protein showed an apparent molecular mass 56, 47 and 39 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Fatty acids were extracted and subjected to gas chromatographic analysis. Conclusions: The antimicrobial activity of the bacteria might be due to the presence of fatty acids and proteins which holds promise for the development of new drugs.

  14. Tricyclic pyrone compounds prevent aggregation and reverse cellular phenotypes caused by expression of mutant huntingtin protein in striatal neurons

    Directory of Open Access Journals (Sweden)

    McMurray Cynthia T

    2009-07-01

    Full Text Available Abstract Background Huntington's disease (HD is a progressive neurodegenerative disorder caused by a CAG repeat expansion mutation in the coding region of a novel gene. The mechanism of HD is unknown. Most data suggest that polyglutamine-mediated aggregation associated with expression of mutant huntingtin protein (mhtt contributes to the pathology. However, recent studies have identified early cellular dysfunctions that preclude aggregate formation. Suppression of aggregation is accepted as one of the markers of successful therapeutic approaches. Previously, we demonstrated that tricyclic pyrone (TP compounds efficiently inhibited formation of amyloid-β (Aβ aggregates in cell and mouse models representing Alzheimer's Disease (AD. In the present study, we aimed to determine whether TP compounds could prevent aggregation and restore early cellular defects in primary embryonic striatal neurons from animal model representing HD. Results TP compounds effectively inhibit aggregation caused by mhtt in neurons and glial cells. Treatment with TP compounds also alleviated cholesterol accumulation and restored clathrin-independent endocytosis in HD neurons. Conclusion We have found that TP compounds not only blocked mhtt-induced aggregation, but also alleviated early cellular dysfunctions that preclude aggregate formation. Our data suggest TP molecules may be used as lead compounds for prevention or treatment of multiple neurodegenerative diseases including HD and AD.

  15. Protein Modification with Amphiphilic Block Copoly(2-oxazoline)s as a New Platform for Enhanced Cellular Delivery

    KAUST Repository

    Tong, Jing

    2010-08-02

    Several homopolymers, random copolymers and block copolymers based on poly(2-oxazoline)s (POx) were synthesized and conjugated to horseradish peroxidase (HRP) using biodegradable and nonbiodegradable linkers. These conjugates were characterized by amino group titration, polyacrylamide gel electrophoresis (PAGE), isoelectric focusing, enzymatic activity assay and conformation analysis. The conjugates contained on average from about one to two polymer chains per enzyme. From 70% to 90% of enzymatic activity was retained in most cases. Circular dichroism (CD) analysis revealed that HRP modification affected the secondary structure of the apoprotein but did not affect the tertiary structure and heme environment. Enhanced cellular uptake was found in the conjugates of two block copolymers using both MDCK cells and Caco-2 cells, but not in the conjugates of random copolymer and homopolymer. Conjugation with a block copolymer of 2-methyl-2-oxazoline and 2-butyl-2-oxazoline led to the highest cellular uptake as compared to other conjugates. Our data indicates that modification with amphiphilic POx has the potential to modulate and enhance cellular delivery of proteins.

  16. SELDI-TOF analysis of glioblastoma cyst fluid is an approach for assessing cellular protein expression

    Science.gov (United States)

    Hoelscher, Martin; Richter, Nina; Melle, Christian; von Eggeling, Ferdinand; Schaenzer, Anne; Nestler, Ulf

    2013-01-01

    Objectives: In about 10% of glioblastoma patients, preoperative MRI discloses the presence of tumor cysts. Whereas the impact of cystic appearance on prognosis has been discussed extensively, only little is known about the tumor cyst fluid. In this study, we tested the feasibility of the surface enhanced laser desorption ionization time of flight (SELDI-TOF) technique to detect cyst fluid proteins. Methods: Cyst fluid was collected from 21 glioblastoma patients for SELDI-TOF analysis and compared to control cerebrospinal fluids from 15 patients with spinal stenosis. Resulting protein peaks with significant differences between groups were further described, using the molecular weight in an internet search of protein databases and publications. Two potential cyst fluid proteins, basigin and ferritin light chain, were selected for immunohistological detection in the histologic slides of the patients, metallothionein (MT) served as negative control. Results: As supposed from the results of the SELDI-TOF analysis, basigin and ferritin were detected immunohistochemically in the cyst wall, whereas MT was more equally distributed between the cyst wall and the surrounding tumor tissue. Median survival time of the patients was 20 months (range 2 to 102 months) and correlated with age, but not with expression of the three proteins. Discussion: The SELDI-TOF approach reveals a number of proteins, potentially present in glioblastoma cyst fluid. Identification of these proteins in tumor cells may help understand the pathogenetic pathways and the prognostic value of cystic changes. PMID:24225180

  17. Cellular RNA binding proteins NS1-BP and hnRNP K regulate influenza A virus RNA splicing.

    Science.gov (United States)

    Tsai, Pei-Ling; Chiou, Ni-Ting; Kuss, Sharon; García-Sastre, Adolfo; Lynch, Kristen W; Fontoura, Beatriz M A

    2013-01-01

    Influenza A virus is a major human pathogen with a genome comprised of eight single-strand, negative-sense, RNA segments. Two viral RNA segments, NS1 and M, undergo alternative splicing and yield several proteins including NS1, NS2, M1 and M2 proteins. However, the mechanisms or players involved in splicing of these viral RNA segments have not been fully studied. Here, by investigating the interacting partners and function of the cellular protein NS1-binding protein (NS1-BP), we revealed novel players in the splicing of the M1 segment. Using a proteomics approach, we identified a complex of RNA binding proteins containing NS1-BP and heterogeneous nuclear ribonucleoproteins (hnRNPs), among which are hnRNPs involved in host pre-mRNA splicing. We found that low levels of NS1-BP specifically impaired proper alternative splicing of the viral M1 mRNA segment to yield the M2 mRNA without affecting splicing of mRNA3, M4, or the NS mRNA segments. Further biochemical analysis by formaldehyde and UV cross-linking demonstrated that NS1-BP did not interact directly with viral M1 mRNA but its interacting partners, hnRNPs A1, K, L, and M, directly bound M1 mRNA. Among these hnRNPs, we identified hnRNP K as a major mediator of M1 mRNA splicing. The M1 mRNA segment generates the matrix protein M1 and the M2 ion channel, which are essential proteins involved in viral trafficking, release into the cytoplasm, and budding. Thus, reduction of NS1-BP and/or hnRNP K levels altered M2/M1 mRNA and protein ratios, decreasing M2 levels and inhibiting virus replication. Thus, NS1-BP-hnRNPK complex is a key mediator of influenza A virus gene expression.

  18. Engineered mutations in fibrillin-1 leading to Marfan syndrome act at the protein, cellular and organismal levels.

    Science.gov (United States)

    Zeyer, Karina A; Reinhardt, Dieter P

    2015-01-01

    Fibrillins are the major components of microfibrils in the extracellular matrix of elastic and non-elastic tissues. They are multi-domain proteins, containing primarily calcium binding epidermal growth factor-like (cbEGF) domains and 8-cysteine/transforming growth factor-beta binding protein-like (TB) domains. Mutations in the fibrillin-1 gene give rise to Marfan syndrome, a connective tissue disorder with clinical complications in the cardiovascular, skeletal, ocular and other organ systems. Here, we review the consequences of engineered Marfan syndrome mutations in fibrillin-1 at the protein, cellular and organismal levels. Representative point mutations associated with Marfan syndrome in affected individuals have been introduced and analyzed in recombinant fibrillin-1 fragments. Those mutations affect fibrillin-1 on a structural and functional level. Mutations which impair folding of cbEGF domains can affect protein trafficking. Protein folding disrupted by some mutations can lead to defective secretion in mutant fibrillin-1 fragments, whereas fragments with other Marfan mutations are secreted normally. Many Marfan mutations render fibrillin-1 more susceptible to proteolysis. There is also evidence that some mutations affect heparin binding. Few mutations have been further analyzed in mouse models. An extensively studied mouse model of Marfan syndrome expresses mouse fibrillin-1 with a missense mutation (p.C1039G). The mice display similar characteristics to human patients with Marfan syndrome. Overall, the analyses of engineered mutations leading to Marfan syndrome provide important insights into the pathogenic molecular mechanisms exerted by mutated fibrillin-1.

  19. Sulfolobus Turreted Icosahedral Virus c92 Protein Responsible for the Formation of Pyramid-Like Cellular Lysis Structures

    DEFF Research Database (Denmark)

    Snyder, Jamie C; Brumfield, Susan K; Peng, Nan;

    2011-01-01

    Host cells infected by Sulfolobus turreted icosahedral virus (STIV) have been shown to produce unusual pyramid-like structures on the cell surface. These structures represent a virus-induced lysis mechanism that is present in Archaea and appears to be distinct from the holin/endolysin system...... described for DNA bacteriophages. This study investigated the STIV gene products required for pyramid formation in its host Sulfolobus solfataricus. Overexpression of STIV open reading frame (ORF) c92 in S. solfataricus alone is sufficient to produce the pyramid-like lysis structures in cells. Gene...... disruption of c92 within STIV demonstrates that c92 is an essential protein for virus replication. Immunolocalization of c92 shows that the protein is localized to the cellular membranes forming the pyramid-like structures....

  20. Sulfolobus turreted icosahedral virus c92 protein responsible for the formation of pyramid-like cellular lysis structures.

    Science.gov (United States)

    Snyder, Jamie C; Brumfield, Susan K; Peng, Nan; She, Qunxin; Young, Mark J

    2011-07-01

    Host cells infected by Sulfolobus turreted icosahedral virus (STIV) have been shown to produce unusual pyramid-like structures on the cell surface. These structures represent a virus-induced lysis mechanism that is present in Archaea and appears to be distinct from the holin/endolysin system described for DNA bacteriophages. This study investigated the STIV gene products required for pyramid formation in its host Sulfolobus solfataricus. Overexpression of STIV open reading frame (ORF) c92 in S. solfataricus alone is sufficient to produce the pyramid-like lysis structures in cells. Gene disruption of c92 within STIV demonstrates that c92 is an essential protein for virus replication. Immunolocalization of c92 shows that the protein is localized to the cellular membranes forming the pyramid-like structures.

  1. Activation of the cellular mitogen-activated protein kinase pathways ERK, P38 and JNK during Toxoplasma gondii invasion

    Directory of Open Access Journals (Sweden)

    Valère A.

    2003-03-01

    Full Text Available Host cell invasion is essential for the pathogenicity of the obligate intracellular protozoan parasite Toxoplasma gondii. In the present study, we evaluated the ability of T. gondii tachyzoites to trigger phosphorylation of the different mitogen-activated protein kinases (MAPK in human monocytic cells THP1. Kinetic experiments show that the peak of extracellular-signal-regulated kinase (ERK 1/2, P38 and cjun-NH2 terminal kinase (JNKs phosphorylation occurs between 10 and 60 min. The use of specific inhibitors of ERK1/2, P38 and JNK1/2 phosphorylation indicates the specificity of MAPKs phosphorylation during invasion. Signaling through cellular and parasite mitogen-activated protein (MAP kinase pathways appears to be critical for T. gondii invasion.

  2. Multiple, but Concerted Cellular Activities of the Human Protein Hap46/BAG-1M and Isoforms

    Directory of Open Access Journals (Sweden)

    Ulrich Gehring

    2009-03-01

    Full Text Available The closely related human and murine proteins Hap46/BAG-1M and BAG-1, respectively, were discovered more than a decade ago by molecular cloning techniques. These and the larger isoform Hap50/BAG-1L, as well as shorter isoforms, have the ability to interact with a seemingly unlimited array of proteins of completely unrelated structures. This problem was partially resolved when it was realized that molecular chaperones of the hsp70 heat shock protein family are major primary association partners, binding being mediated by the carboxy terminal BAG-domain and the ATP-binding domain of hsp70 chaperones. The latter, in turn, can associate with an almost unlimited variety of proteins through their substrate-binding domains, so that ternary complexes may result. The protein folding activity of hsp70 chaperones is affected by interactions with Hap46/BAG-1M or isoforms. However, there also exist several proteins which bind to Hap46/BAG-1M and isoforms independent of hsp70 mediation. Moreover, Hap46/BAG-1M and Hap50/BAG-1L, but not the shorter isoforms, can bind to DNA in a sequence-independent manner by making use of positively charged regions close to their amino terminal ends. This is the molecular basis for their effects on transcription which are of major physiological relevance, as discussed here in terms of a model. The related proteins Hap50/BAG-1L and Hap46/BAG-1M may thus serve as molecular links between such diverse bioactivities as regulation of gene expression and protein quality control. These activities are coordinated and synergize in helping cells to cope with conditions of external stress. Moreover, they recently became markers for the aggressiveness of several cancer types.

  3. Cellular and Molecular Roles of the Akt Protein Kinase in Breast Carcinomas

    Science.gov (United States)

    1999-06-01

    are in progress. Identification of Akt interacting proteins We proposed to identify targets of Akt using a yeast two-hybrid screen (1). We have...studies in Task 2. Key Research Accomplishments "* Identified Akt interacting proteins using a yeast two-hybrid screen "* Provided secondary evidence...human breast cancer lines (5). Therefore, our studies in the future will also focus on the regulation of Oct3 by Akt. Identification of AKT Interacting

  4. Discovery of cellular proteins required for the early steps of HCV infection using integrative genomics.

    Directory of Open Access Journals (Sweden)

    Ji Hoon Park

    Full Text Available Successful viral infection requires intimate communication between virus and host cell, a process that absolutely requires various host proteins. However, current efforts to discover novel host proteins as therapeutic targets for viral infection are difficult. Here, we developed an integrative-genomics approach to predict human genes involved in the early steps of hepatitis C virus (HCV infection. By integrating HCV and human protein associations, co-expression data, and tight junction-tetraspanin web specific networks, we identified host proteins required for the early steps in HCV infection. Moreover, we validated the roles of newly identified proteins in HCV infection by knocking down their expression using small interfering RNAs. Specifically, a novel host factor CD63 was shown to directly interact with HCV E2 protein. We further demonstrated that an antibody against CD63 blocked HCV infection, indicating that CD63 may serve as a new therapeutic target for HCV-related diseases. The candidate gene list provides a source for identification of new therapeutic targets.

  5. Proteome analyses of cellular proteins in methicillin-resistant Staphylococcus aureus treated with rhodomyrtone, a novel antibiotic candidate.

    Directory of Open Access Journals (Sweden)

    Wipawadee Sianglum

    Full Text Available The ethanolic extract from Rhodomyrtus tomentosa leaf exhibited good antibacterial activities against both methicillin-resistant Staphylococcus aureus (MRSA and S. aureus ATCC 29213. Its minimal inhibitory concentration (MIC values ranged from 31.25-62.5 µg/ml, and the minimal bactericidal concentration (MBC was 250 µg/ml. Rhodomyrtone, an acylphloroglucinol derivative, was 62.5-125 times more potent at inhibiting the bacteria than the ethanolic extract, the MIC and MBC values were 0.5 µg/ml and 2 µg/ml, respectively. To provide insights into antibacterial mechanisms involved, the effects of rhodomyrtone on cellular protein expression of MRSA have been investigated using proteomic approaches. Proteome analyses revealed that rhodomyrtone at subinhibitory concentration (0.174 µg/ml affected the expression of several major functional classes of whole cell proteins in MRSA. The identified proteins involve in cell wall biosynthesis and cell division, protein degradation, stress response and oxidative stress, cell surface antigen and virulence factor, and various metabolic pathways such as amino acid, carbohydrate, energy, lipid, and nucleotide metabolism. Transmission electron micrographs confirmed the effects of rhodomyrtone on morphological and ultrastructural alterations in the treated bacterial cells. Biological processes in cell wall biosynthesis and cell division were interrupted. Prominent changes including alterations in cell wall, abnormal septum formation, cellular disintegration, and cell lysis were observed. Unusual size and shape of staphylococcal cells were obviously noted in the treated MRSA. These pioneer findings on proteomic profiling and phenotypic features of rhodomyrtone-treated MRSA may resolve its antimicrobial mechanisms which could lead to the development of a new effective regimen for the treatment of MRSA infections.

  6. The effect of extracellular matrix proteins on the cellular response of HUVECS and HOBS after covalent immobilization onto titanium.

    Science.gov (United States)

    Heller, Martin; Kämmerer, Peer W; Al-Nawas, Bilal; Luszpinski, Marie-Anne; Förch, Renate; Brieger, Jürgen

    2015-06-01

    Biomimetic surface modifications are regarded as promising approach to stimulate cellular behavior at the interface of implant materials. Aim of the study was an evaluation of the cellular response of human umbilical cord cells (HUVECS) and human osteoblasts (HOBS) on titanium covalently coated with the extracellular matrix (ECM) proteins fibrinogen, collagen, laminin, and osteopontin. For the surface modification, titanium discs were first amino-functionalized by plasma polymerization of allylamine. The ECM protein conjugation was performed using the linker molecule α, ω-bis-N-hydroxysuccinimide polyethylene glycol (Di-NHS linker). For surface characterization, infrared spectroscopy and fluorescein isothiocyanate staining (FITC) were used to evaluate the presence and distribution of primary amines in the plasma polymer film. Real-time analyses of the respective protein conjugation processes were performed via surface plasmon resonance kinetic measurements. All ECM proteins were immobilized successfully. Furthermore, the biological functionality of the conjugated factors fibronectin and collagen could be proven as they led to a distinct stimulation of cell adhesion of HUVECS and HOBS when compared to the control group. The highest cell coverage of HUVECS was observed on fibronectin-modified surfaces with approximately 35% and on collagen with 33% after 24 h (PT: 9.4%). For laminin, no additional effect was observed, and for osteopontin, only a slight enhancement of cell adhesion was found. A similar, cell-stimulating tendency of fibronectin and collagen was seen as well after 3 and 7 days. Biomimetic surface modification via plasma polymerization is a powerful method for biomolecule conjugation with a high retention of biological functionality and offer promising clinical perspectives.

  7. Influence of silk-silica fusion protein design on silica condensation in vitro and cellular calcification

    Science.gov (United States)

    Plowright, Robyn; Dinjaski, Nina; Zhou, Shun; Belton, David J.; Kaplan, David L.; Perry, Carole C.

    2016-01-01

    Biomaterial design via genetic engineering can be utilized for the rational functionalization of proteins to promote biomaterial integration and tissue regeneration. Spider silk has been extensively studied for its biocompatibility, biodegradability and extraordinary material properties. As a protein-based biomaterial, recombinant DNA derived derivatives of spider silks have been modified with biomineralization domains which lead to silica deposition and potentially accelerated bone regeneration. However, the influence of the location of the R5 (SSKKSGSYSGSKGSKRRIL) silicifying domain fused with the spider silk protein sequence on the biosilicification process remains to be determined. Here we designed two silk-R5 fusion proteins that differed in the location of the R5 peptide, C- vs. N-terminus, where the spider silk domain consisted of a 15mer repeat of a 33 amino acid consensus sequence of the major ampullate dragline Spidroin 1 from Nephila clavipes (SGRGGLGGQG AGAAAAAGGA GQGGYGGLGSQGT). The chemical, physical and silica deposition properties of these recombinant proteins were assessed and compared to a silk 15mer control without the R5 present. The location of the R5 peptide did not have a significant effect on wettability and surface energies, while the C-terminal location of the R5 promoted more controlled silica precipitation, suggesting differences in protein folding and possibly different access to charged amino acids that drive the silicification process. Further, cell compatibility in vitro, as well as the ability to promote human bone marrow derived mesenchymal stem cell (hMSC) differentiation were demonstrated for both variants of the fusion proteins. PMID:26989487

  8. Fatty Acid-Binding Protein in Small Intestine IDENTIFICATION, ISOLATION, AND EVIDENCE FOR ITS ROLE IN CELLULAR FATTY ACID TRANSPORT

    Science.gov (United States)

    Ockner, Robert K.; Manning, Joan A.

    1974-01-01

    A soluble fatty acid-binding protein (FABP), mol wt ∼ 12,000 is present in intestinal mucosa and other tissues that utilize fatty acids, including liver, myocardium, adipose, and kidney. This protein binds long chain fatty acids both in vivo and in vitro. FABP was isolated from rat intestine by gel filtration and isoelectric focusing. It showed a reaction of complete immunochemical identity with proteins in the 12,000 mol wt fatty acid-binding fractions of liver, myocardium, and adipose tissue supernates. (The presence of immunochemically nonidentical 12,000 mol wt FABP in these tissues is not excluded.) By quantitative radial immunodiffusion, supernatant FABP concentration in mucosa from proximal and middle thirds of jejuno-ileum significantly exceeded that in distal third, duodenum, and liver, expressed as micrograms per milligram soluble protein, micrograms per gram DNA, and micrograms per gram tissue. FABP concentration in villi was approximately three times greater than in crypts. Small quantities of FABP were present in washed nuclei-cell membrane, mitochondrial and microsomal fractions. However, the amount of FABP solubilized per milligram membrane protein was similar for all particulate fractions, and total membrane-associated FABP was only about 16% of supernatant FABP. Intestinal FABP concentration was significantly greater in animals maintained on high fat diets than on low fat; saturated and unsaturated fat diets did not differ greatly in this regard. The preponderance of FABP in villi from proximal and middle intestine, its ability to bind fatty acids in vivo as well as in vitro, and its response to changes in dietary fat intake support the concept that this protein participates in cellular fatty acid transport during fat absorption. Identical or closely related 12,000 mol wt proteins may serve similar functions in other tissues. Images PMID:4211161

  9. Cdc42 Effector Protein 2 (XCEP2 is required for normal gastrulation and contributes to cellular adhesion in Xenopus laevis

    Directory of Open Access Journals (Sweden)

    Nelson Richard W

    2004-10-01

    Full Text Available Abstract Background Rho GTPases and their downstream effector proteins regulate a diverse array of cellular processes during embryonic development, including reorganization of cytoskeletal architecture, cell adhesion, and transcription. Changes in the activation state of Rho GTPases are converted into changes in cellular behavior by a diversity of effector proteins, which are activated in response to changes in the GTP binding state of Rho GTPases. In this study we characterize the expression and function of one such effector, XCEP2, that is present during gastrulation stages in Xenopus laevis. Results In a search for genes whose expression is regulated during early stages of embryonic development in Xenopus laevis, a gene encoding a Rho GTPase effector protein (Xenopus Cdc42 effector protein 2, or XCEP2 was isolated, and found to be highly homologous, but not identical, to a Xenopus sequence previously submitted to the Genbank database. These two gene sequences are likely pseudoalleles. XCEP2 mRNA is expressed at constant levels until mid- to late- gastrula stages, and then strongly down-regulated at late gastrula/early neurula stages. Injection of antisense morpholino oligonucleotides directed at one or both pseudoalleles resulted in a significant delay in blastopore closure and interfered with normal embryonic elongation, suggesting a role for XCEP2 in regulating gastrulation movements. The morpholino antisense effect could be rescued by co-injection with a morpholino-insensitive version of the XCEP2 mRNA. Antisense morpholino oligonucleotides were found to have no effect on mesodermal induction, suggesting that the observed effects were due to changes in the behavior of involuting cells, rather than alterations in their identity. XCEP2 antisense morpholino oligonucleotides were also observed to cause complete disaggregation of cells composing animal cap explants, suggesting a specific role of XCEP2 in maintenance or regulation of cell

  10. Analysis of HPV-16 early gene regulationin cellular differentiation, includingcharacterisation of the possiblerole of CPEB proteins

    DEFF Research Database (Denmark)

    Hansen, Christina Neigaard

    cytoplasmic polyadenylation elements (CPEs) situated in the distal part of the messengers. These CPE sequences bind the CPE-binding protein CPEB. In this study, the mRNA levels of the 4 CPEBs in primary keratinocytes, in 8 different cell lines, and in both normal and cancer genital tissues have been analysed....... Huge variations among both the different cell types and the 4 CPEBs were observed. Interestingly, in ovarian cancer we found downregulated mRNA levels of CPEB1, a protein that previously has been suggested to be a tumor suppressor protein. We also found a tendency for the CPEB3 mRNA to be downregulated...... E6/E7 expression. HPV-16 preferably infects the proliferating cells of the continually renewing stratified epithelium lining the genital tract. These proliferating cells will differentiate as they are pushed upwards in the epithelium by newly produced daughter cells. The virus life cycle is tightly...

  11. Creative elements: network-based predictions of active centres in proteins, cellular and social networks

    CERN Document Server

    Csermely, Peter

    2008-01-01

    Active centres and hot spots of proteins have a paramount importance in enzyme action, protein complex formation and drug design. Recently a number of publications successfully applied the analysis of residue networks to predict active centres in proteins. Most real-world networks show a number of properties, such as small-worldness or scale-free degree distribution, which are rather general features of networks from molecules to the society. Based on extensive analogies I propose that the existing findings and methodology enable us to detect active centres in cells, social networks and ecosystems. Members of these active centres are creative elements of the respective networks, which may help them to survive unprecedented, novel challenges, and play a key role in the development, survival and evolvability of complex systems.

  12. Genome-wide Mapping of Cellular Protein-RNA Interactions Enabled by Chemical Crosslinking

    Institute of Scientific and Technical Information of China (English)

    Xiaoyu Li; Jinghui Song; Chengqi Yi

    2014-01-01

    RNA-protein interactions influence many biological processes. Identifying the binding sites of RNA-binding proteins (RBPs) remains one of the most fundamental and important chal-lenges to the studies of such interactions. Capturing RNA and RBPs via chemical crosslinking allows stringent purification procedures that significantly remove the non-specific RNA and protein interactions. Two major types of chemical crosslinking strategies have been developed to date, i.e., UV-enabled crosslinking and enzymatic mechanism-based covalent capture. In this review, we com-pare such strategies and their current applications, with an emphasis on the technologies themselves rather than the biology that has been revealed. We hope such methods could benefit broader audi-ence and also urge for the development of new methods to study RNA RBP interactions.

  13. Reaction of small heat-shock proteins to different kinds of cellular stress in cultured rat hippocampal neurons.

    Science.gov (United States)

    Bartelt-Kirbach, Britta; Golenhofen, Nikola

    2014-01-01

    Upregulation of small heat-shock proteins (sHsps) in response to cellular stress is one mechanism to increase cell viability.We previously described that cultured rat hippocampal neurons express five of the 11 family members but only upregulate two of them (HspB1 and HspB5) at the protein level after heat stress. Since neurons have to cope with many other pathological conditions, we investigated in this study the expression of all five expressed sHsps on mRNA and protein level after sublethal sodium arsenite and oxidative and hyperosmotic stress. Under all three conditions, HspB1, HspB5, HspB6, and HspB8 but not HspB11 were consistently upregulated but showed differences in the time course of upregulation. The increase of sHsps always occurred earlier on mRNA level compared with protein levels. We conclude from our data that these four upregulated sHsps (HspB1, HspB5, HspB6, HspB8) act together in different proportions in the protection of neurons from various stress conditions.

  14. Conformational landscape of an amyloid intra-cellular domain and Landau-Ginzburg-Wilson paradigm in protein dynamics.

    Science.gov (United States)

    Dai, Jin; Niemi, Antti J; He, Jianfeng

    2016-07-28

    The Landau-Ginzburg-Wilson paradigm is proposed as a framework, to investigate the conformational landscape of intrinsically unstructured proteins. A universal Cα-trace Landau free energy is deduced from general symmetry considerations, with the ensuing all-atom structure modeled using publicly available reconstruction programs Pulchra and Scwrl. As an example, the conformational stability of an amyloid precursor protein intra-cellular domain (AICD) is inspected; the reference conformation is the crystallographic structure with code 3DXC in Protein Data Bank (PDB) that describes a heterodimer of AICD and a nuclear multi-domain adaptor protein Fe65. Those conformations of AICD that correspond to local or near-local minima of the Landau free energy are identified. For this, the response of the original 3DXC conformation to variations in the ambient temperature is investigated, using the Glauber algorithm. The conclusion is that in isolation the AICD conformation in 3DXC must be unstable. A family of degenerate conformations that minimise the Landau free energy is identified, and it is proposed that the native state of an isolated AICD is a superposition of these conformations. The results are fully in line with the presumed intrinsically unstructured character of isolated AICD and should provide a basis for a systematic analysis of AICD structure in future NMR experiments.

  15. Conformational landscape of an amyloid intra-cellular domain and Landau-Ginzburg-Wilson paradigm in protein dynamics

    Science.gov (United States)

    Dai, Jin; Niemi, Antti J.; He, Jianfeng

    2016-07-01

    The Landau-Ginzburg-Wilson paradigm is proposed as a framework, to investigate the conformational landscape of intrinsically unstructured proteins. A universal Cα-trace Landau free energy is deduced from general symmetry considerations, with the ensuing all-atom structure modeled using publicly available reconstruction programs Pulchra and Scwrl. As an example, the conformational stability of an amyloid precursor protein intra-cellular domain (AICD) is inspected; the reference conformation is the crystallographic structure with code 3DXC in Protein Data Bank (PDB) that describes a heterodimer of AICD and a nuclear multi-domain adaptor protein Fe65. Those conformations of AICD that correspond to local or near-local minima of the Landau free energy are identified. For this, the response of the original 3DXC conformation to variations in the ambient temperature is investigated, using the Glauber algorithm. The conclusion is that in isolation the AICD conformation in 3DXC must be unstable. A family of degenerate conformations that minimise the Landau free energy is identified, and it is proposed that the native state of an isolated AICD is a superposition of these conformations. The results are fully in line with the presumed intrinsically unstructured character of isolated AICD and should provide a basis for a systematic analysis of AICD structure in future NMR experiments.

  16. Mycoplasma hyopneumoniae and Mycoplasma flocculare differential domains from orthologous surface proteins induce distinct cellular immune responses in mice.

    Science.gov (United States)

    Leal, Fernanda Munhoz Dos Anjos; Virginio, Veridiana Gomes; Martello, Carolina Lumertz; Paes, Jéssica Andrade; Borges, Thiago J; Jaeger, Natália; Bonorino, Cristina; Ferreira, Henrique Bunselmeyer

    2016-07-15

    Mycoplasma hyopneumoniae and Mycoplasma flocculare are two genetically close species found in the swine respiratory tract. Despite their similarities, while M. hyopneumoniae is the causative agent of porcine enzootic pneumonia, M. flocculare is a commensal bacterium. Genomic and transcriptional comparative analyses so far failed to explain the difference in pathogenicity between these two species. We then hypothesized that such difference might be, at least in part, explained by amino acid sequence and immunological or functional differences between ortholog surface proteins. In line with that, it was verified that approximately 85% of the ortholog surface proteins from M. hyopneumoniae 7448 and M. flocculare present one or more differential domains. To experimentally assess possible immunological implications of this kind of difference, the extracellular differential domains from one pair of orthologous surface proteins (MHP7448_0612, from M. hyopneumoniae, and MF_00357, from M. flocculare) were expressed in E. coli and used to immunize mice. The recombinant polypeptides (rMHP61267-169 and rMF35767-196, respectively) induced distinct cellular immune responses. While, rMHP61267-169 induced both Th1 and Th2 responses, rMF35767-196 induced just an early pro-inflammatory response. These results indicate that immunological properties determined by differential domains in orthologous surface protein might play a role in pathogenicity, contributing to elicit specific and differential immune responses against each species.

  17. Role of Crk Adaptor Proteins in Cellular Migration and Invasion in Human Breast Cancer

    Science.gov (United States)

    2007-03-01

    adapter protein. Mol Cell Biol. 19(12):8169-79. 22. Cabodi S, Tinnirello A, Di Stefano P, Bisaro B, Ambrosino E, Castellano I, Sapino A, Arisio R...Vande Woude GF. Met, metastasis, motility and more. Nat Rev Mol Cell Biol 2003;4:915 –25. 3. Rosario M, Birchmeier W. How to make tubes: signaling by

  18. Characterization of membrane protein trafficking and cellular signaling at the primary cilium

    DEFF Research Database (Denmark)

    Mogensen, Johanne Bay

    original articles (articles III and IV), which focuses on two specific signaling systems, conducted via the primary cilium; the Sonic hedgehog (SHH) and the Transforming growth factor β (TGFβ) signaling pathways. In article III we show that the motor protein, KIF13B, via its interaction with the transition...

  19. Inactivation of cellular enzymes by carbonyls and protein-bound glycation/glycoxidation products

    DEFF Research Database (Denmark)

    Morgan, Philip E; Dean, Roger T; Davies, Michael Jonathan

    2002-01-01

    Diabetic plasma contains elevated levels of glucose and various low-molecular-weight carbonyl compounds derived from the metabolism of glucose and related materials. These compounds react with protein side chains (Arg, Lys, Cys, and His) to give glycated materials and advanced glycation end produ...

  20. Host- and Strain-Specific Regulation of Influenza Virus Polymerase Activity by Interacting Cellular Proteins

    NARCIS (Netherlands)

    Bortz, Eric; Westera, Liset; Maamary, Jad; Steel, John; Albrecht, Randy A.; Manicassamy, Balaji; Chase, Geoffrey; Martinez-Sobrido, Luis; Schwemmle, Martin; Garcia-Sastre, Adolfo

    2011-01-01

    Highly pathogenic avian influenza A (HPAI) viruses of the H5N1 subtype have recently emerged from avian zoonotic reservoirs to cause fatal human disease. Adaptation of HPAI virus RNA-dependent RNA polymerase (PB1, PB2, and PA proteins) and nucleoprotein (NP) to interactions with mammalian host prote

  1. The Intracellular Destiny of the Protein Corona : A Study on its Cellular Internalization and Evolution

    NARCIS (Netherlands)

    Bertoli, Filippo; Garry, David; Monopoli, Marco P.; Salvati, Anna; Dawson, Kenneth A.

    2016-01-01

    It has been well established that the early stages of nanoparticle cell interactions are governed, at least in part, by the layer of proteins and other biomolecules adsorbed and slowly exchanged with the surrounding biological media (biomolecular corona). Subsequent to membrane interactions, nanopar

  2. Anchoring secreted proteins in endoplasmic reticulum by plant oleosin: the example of vitamin B12 cellular sequestration by transcobalamin.

    Directory of Open Access Journals (Sweden)

    Laurent Pons

    Full Text Available BACKGROUND: Oleosin is a plant protein localized to lipid droplets and endoplasmic reticulum of plant cells. Our idea was to use it to target functional secretory proteins of interest to the cytosolic side of the endoplasmic reticulum of mammalian cells, through expressing oleosin-containing chimeras. We have designed this approach to create cellular models deficient in vitamin B12 (cobalamin because of the known problematics associated to the obtainment of effective vitamin B12 deficient cell models. This was achieved by the overexpression of transcobalamin inside cells through anchoring to oleosin. METHODOLOGY: chimera gene constructs including transcobalamin-oleosin (TC-O, green fluorescent protein-transcobalamin-oleosin (GFP-TC-O and oleosin-transcobalamin (O-TC were inserted into pAcSG2 and pCDNA3 vectors for expression in sf9 insect cells, Caco2 (colon carcinoma, NIE-115 (mouse neuroblastoma, HEK (human embryonic kidney, COS-7 (Green Monkey SV40-transfected kidney fibroblasts and CHO (Chinese hamster ovary cells. The subcellular localization, the changes in vitamin B12 binding activity and the metabolic consequences were investigated in both Caco2 and NIE-115 cells. PRINCIPAL FINDINGS: vitamin B12 binding was dramatically higher in TC-O than that in O-TC and wild type (WT. The expression of GFP-TC-O was observed in all cell lines and found to be co-localized with an ER-targeted red fluorescent protein and calreticulin of the endoplasmic reticulum in Caco2 and COS-7 cells. The overexpression of TC-O led to B12 deficiency, evidenced by impaired conversion of cyano-cobalamin to ado-cobalamin and methyl-cobalamin, decreased methionine synthase activity and reduced S-adenosyl methionine to S-adenosyl homocysteine ratio, as well as increases in homocysteine and methylmalonic acid concentration. CONCLUSIONS/SIGNIFICANCE: the heterologous expression of TC-O in mammalian cells can be used as an effective strategy for investigating the cellular

  3. Investigation of cellular and protein interactions with model self-assembled monolayer surfaces

    Science.gov (United States)

    Tegoulia, Vassiliki Apostolou

    Self-assembled monolayers (SAMs) of alkanethiolates on gold have been used to investigate the effect of substrate surface properties on bacterial and blood cell adhesion in the presence and absence of blood proteins. Protein adsorption and binding strength on SAMs as well as complement activation by these model surfaces were also studied. It is hoped that information gained, regarding factors that influence biological processes, will lead to strategies for designing materials and surfaces that specifically inhibit cell adhesion and protein adsorption. Single component SAMs of the general formula HS(CH2) 10X, where X = CH3, CH2OH. COOH and CH2(OCH 2CH2)3OH, and two component mixed SAMs created from binary solutions of HS(CH2), OCH3 and HS(CH 2)10CH2OH, were used. Adhesion was investigated under well-defined flow conditions. Adhesion was found to be higher for the hydrophobic methyl and minimal for the tri(ethyleneoxide) terminated SAM. Preincubation of the SAMs with fibrinogen led to an increase in cell adhesion for bacteria and a decrease for leukocyte adhesion. The effect of surface chemistry on protein adsorption was studied for three blood proteins, fibrinogen, fibronectin and albumin. Adsorption was found to be higher on the hydrophobic CH3 surface and lower but comparable for the other surfaces while proteins adsorbed strongly on all surfaces. SAMs were also used to evaluate complement activation by foreign surfaces. The hydroxyl rich SAMs were found to activate complement more significantly than the anionic carboxyl and the hydrophobic methyl terminated SAMs. A surface modification was introduced to incorporate a zwitterionic phosphorylcholine (PC) group on a hydroxyl monolayer in an effort to create a biomimetic surface that could minimize cell adhesion and protein adsorption. The good antifouling properties of the phosphorylcholine modified surface led to the synthesis of a novel phosphorylcholine functionalized thiol. Single component and two component

  4. Trans-cellular introduction of HIV-1 protein Nef induces pathogenic response in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Aamir Nazir

    Full Text Available BACKGROUND: Caenorhabditis elegans has emerged as a very powerful model for studying the host pathogen interactions. Despite the absence of a naturally occurring viral infection for C. elegans, the model is now being exploited experimentally to study the basic aspects of virus-host interplay. The data generated from recent studies suggests that the virus that infects mammalian cells does infect, replicate and accumulate in C. elegans. METHODOLOGY/PRINCIPAL FINDINGS: We took advantage of the easy-to-achieve protein introduction in C. elegans and employing the methodology, we administered HIV-1 protein Nef into live worms. Nef is known to be an important protein for exacerbating HIV-1 pathogenesis in host by enhancing viral replication. The deletion of nef from the viral genome has been reported to inhibit its replication in the host, thereby leading to delayed pathogenesis. Our studies, employing Nef introduction into C. elegans, led to creation of an in-vivo model that allowed us to study, whether or not, the protein induces effect in the whole organism. We observed a marked lipodystrophy, effect on neuromuscular function, impaired fertility and reduced longevity in the worms exposed to Nef. The observed effects resemble to those observed in Nef transgenic mice and most interestingly the effects also relate to some of the pathogenic aspects exhibited by human AIDS patients. CONCLUSIONS/SIGNIFICANCE: Our studies underline the importance of this in vivo model for studying the interactions of Nef with host proteins, which could further be used for identifying possible inhibitors of such interactions.

  5. Cellular localization and biochemical characterization of a novel calcium-dependent protein kinase from tobacco

    Institute of Scientific and Technical Information of China (English)

    Yun WANG; Mei ZHANG; Ke KE; Ying Tang LU

    2005-01-01

    By screening tobacco cDNA library with MCK1 as a probe, we isolated a cDNA clone NtCPK5 (accession number AY971376), which encodes a typical calcium-dependent protein kinase. Sequence analyses indicated that NtCPK5 is related to both CPKs and CRKs superfamilies and has all of the three conserved domains of CPKs. The biochemical activity of NtCPK5 was calcium-dependent. NtCPK5 had Vmax and Km of 526 nmol/min/mg and 210 μg/ml respectively with calf thymus histone (fraction Ⅲ, abbreviated to histone Ⅲs) as substrate. For substrate syntide-2, NtCPK5 showed a higher. Vmax of 2008 nmol/min/mg and a lower Km of 30 μM. The K0.5 of calcium activation was 0.04 μM or 0.06 μM for histone Ⅲs or syntide-2 respectively. The putative myristoylation and palmitoylation consensus sequence of NtCPK5 suggests that it could be a membrane-anchoring protein. Indeed, our transient expression experiments with wild type and mutant forms of NtCPK5/GFP fusion proteins showed that NtCPK5 was localized to the plasma membrane of onion epidermal cells and that the localization required the N-terminal acylation sites of NtCPK5/GFP. Taking together, our data have demonstrated the biochemical characteristics of a novel protein NtCPK5 and its subcellular localization as a membrane-anchoring protein.

  6. Sheep scrapie susceptibility-linked polymorphisms do not modulate the initial binding of cellular to disease-associated prion protein prior to conversion

    NARCIS (Netherlands)

    Rigter, A.; Bossers, A.

    2005-01-01

    Conversion of the host-encoded protease-sensitive cellular prion protein (PrPC) into the scrapie-associated protease-resistant isoform (PrPSc) of prion protein (PrP) is the central event in transmissible spongiform encephalopathies or prion diseases. Differences in transmissibility and susceptibilit

  7. Viral and cellular SOS-regulated motor proteins: dsDNA translocation mechanisms with divergent functions.

    Science.gov (United States)

    Wolfe, Annie; Phipps, Kara; Weitao, Tao

    2014-01-01

    DNA damage attacks on bacterial cells have been known to activate the SOS response, a transcriptional response affecting chromosome replication, DNA recombination and repair, cell division and prophage induction. All these functions require double-stranded (ds) DNA translocation by ASCE hexameric motors. This review seeks to delineate the structural and functional characteristics of the SOS response and the SOS-regulated DNA translocases FtsK and RuvB with the phi29 bacteriophage packaging motor gp16 ATPase as a prototype to study bacterial motors. While gp16 ATPase, cellular FtsK and RuvB are similarly comprised of hexameric rings encircling dsDNA and functioning as ATP-driven DNA translocases, they utilize different mechanisms to accomplish separate functions, suggesting a convergent evolution of these motors. The gp16 ATPase and FtsK use a novel revolution mechanism, generating a power stroke between subunits through an entropy-DNA affinity switch and pushing dsDNA inward without rotation of DNA and the motor, whereas RuvB seems to employ a rotation mechanism that remains to be further characterized. While FtsK and RuvB perform essential tasks during the SOS response, their roles may be far more significant as SOS response is involved in antibiotic-inducible bacterial vesiculation and biofilm formation as well as the perspective of the bacteria-cancer evolutionary interaction.

  8. Enhanced susceptibility of T lymphocytes to oxidative stress in the absence of the cellular prion protein.

    Science.gov (United States)

    Aude-Garcia, Catherine; Villiers, Christian; Candéias, Serge M; Garrel, Catherine; Bertrand, Caroline; Collin, Véronique; Marche, Patrice N; Jouvin-Marche, Evelyne

    2011-02-01

    The cellular prion glycoprotein (PrP(C)) is ubiquitously expressed but its physiologic functions remain enigmatic, particularly in the immune system. Here, we demonstrate in vitro and in vivo that PrP(C) is involved in T lymphocytes response to oxidative stress. By monitoring the intracellular level of reduced glutathione, we show that PrP(-/-) thymocytes display a higher susceptibility to H(2)O(2) exposure than PrP(+/+) cells. Furthermore, we find that in mice fed with a restricted diet, a regimen known to increase the intracellular level of ROS, PrP(-/-) thymocytes are more sensitive to oxidative stress. PrP(C) function appears to be specific for oxidative stress, since no significant differences are observed between PrP(-/-) and PrP(+/+) mice exposed to other kinds of stress. We also show a marked evolution of the redox status of T cells throughout differentiation in the thymus. Taken together, our results clearly ascribe to PrP(C) a protective function in thymocytes against oxidative stress.

  9. Potassium-transporting proteins in skeletal muscle: cellular location and fiber-type differences

    DEFF Research Database (Denmark)

    Kristensen, Michael; Juel, Carsten

    2010-01-01

    , but is suggested primarily to participate in K+ release to the interstitium. Because there is restricted diffusion of K+ to the interstitium, K+ released to the T-tubules during AP propagation will be removed primarily by reuptake mediated by transport proteins located in the T-tubule membrane. The most important......Potassium (K+) displacement in skeletal muscle may be an important factor in the development of muscle fatigue during intense exercise. It has been shown in vitro that an increase in the extracellular K+ concentration ([K+]e) to values higher than approx. 10 mm significantly reduce force...... protein that mediates K+ reuptake in the T-tubules is the Na+,K+-ATPase a2 dimers, but a significant contribution of the strong inward rectifier K+ (Kir2.1) channel is also suggested. The Na+, K+, 2Cl- 1 (NKCC1) cotransporter also participates in K+ reuptake but probably mainly from the interstitium...

  10. Genetically encoded norbornene directs site-specific cellular protein labelling via a rapid bioorthogonal reaction

    OpenAIRE

    Lang, Kathrin; Davis, Lloyd; Torres-Kolbus, Jessica; Chou, Chungjung; Deiters, Alexander; Chin, Jason W.

    2012-01-01

    The site-specific incorporation of bioorthogonal groups via genetic code expansion provides a powerful general strategy for site-specifically labelling proteins with any probe. However, the slow reactivity of the bioorthogonal functional groups that can be encoded genetically limits the utility of this strategy. We demonstrate the genetic encoding of a norbornene amino acid using the pyrrolysyl tRNA synthetase/tRNACUA pair in Escherichia coli and mammalian cells. We developed a series of tetr...

  11. D-Ribose Induces Cellular Protein Glycation and Impairs Mouse Spatial Cognition

    OpenAIRE

    Chanshuai Han; Yang Lu; Yan Wei; Ying Liu; Rongqiao He

    2011-01-01

    BACKGROUND: D-ribose, an important reducing monosaccharide, is highly active in the glycation of proteins, and results in the rapid production of advanced glycation end products (AGEs) in vitro. However, whether D-ribose participates in glycation and leads to production of AGEs in vivo still requires investigation. METHODOLOGY/PRINCIPAL FINDINGS: Here we treated cultured cells and mice with D-ribose and D-glucose to compare ribosylation and glucosylation for production of AGEs. Treatment with...

  12. DNA replication restart and cellular dynamics of Hef helicase/nuclease protein in Haloferax volcanii.

    Science.gov (United States)

    Lestini, Roxane; Delpech, Floriane; Myllykallio, Hannu

    2015-11-01

    Understanding how frequently spontaneous replication arrests occur and how archaea deal with these arrests are very interesting and challenging research topics. Here we will described how genetic and imaging studies have revealed the central role of the archaeal helicase/nuclease Hef belonging to the XPF/MUS81/FANCM family of endonucleases in repair of arrested replication forks. Special focus will be on description of a recently developed combination of genetic and imaging tools to study the dynamic localization of a functional Hef::GFP (Green Fluorescent Protein) fusion protein in the living cells of halophilic archaea Haloferax volcanii. As Archaea provide an excellent and unique model for understanding how DNA replication is regulated to allow replication of a circular DNA molecule either from single or multiple replication origins, we will also summarize recent studies that have revealed peculiar features regarding DNA replication, particularly in halophilic archaea. We strongly believe that fundamental knowledge of our on-going studies will shed light on the evolutionary history of the DNA replication machinery and will help to establish general rules concerning replication restart and the key role of recombination proteins not only in bacteria, yeast and higher eukaryotes but also in archaea.

  13. Cellular response to poly(vinyl alcohol) nanofibers coated with biocompatible proteins and polysaccharides

    Science.gov (United States)

    Lee, So Young; Jang, Da Hyun; Kang, Yun Ok; Kim, O. Bok; Jeong, Lim; Kang, Hyun Ki; Lee, Seung Jin; Lee, Chong-Heon; Park, Won Ho; Min, Byung-Moo

    2012-07-01

    A PVA nanofibrous matrix was prepared by electrospinning an aqueous 10 wt% PVA solution. The mean diameter of the PVA nanofibers electrospun from the aqueous PVA solution was 240 nm. The water resistance of the as-spun PVA nanofibrous matrix was improved by physically crosslinking the PVA nanofibers by heat treatment at 150 °C for 10 min. In addition, the heat-treated PVA nanofibrous matrix was coated with biocompatible polysaccharides (chitosan (CHI) or hyaluronic acid (HA)) and proteins (collagen (COL) or silk fibroin (SF)) to construct biomimetic nanofibrous scaffolds. The coating of proteins or polysaccharides on the PVA nanofibrous matrix was confirmed by ATR-IR spectra, and the degree of coating was determined by elemental analysis based on nitrogen content. The coated PVA matrices exhibited less hydrophilicity, except for the HA coating, and better tensile properties than the pure PVA nanofibrous matrix. The increase in tensile properties was due to interfiber bonds formed by the coating. The effect of protein and polysaccharide coating on normal human keratinocytes (NHEKs) and fibroblasts (NHEFs) was examined by cytocompatibility assessment in vitro. Among the CHI-, COL-, HA- and SF-coated PVA matrices, the SF-coated PVA nanofibrous matrix was found to be the most promising scaffold for the attachment and spreading of NHEKs and NHEFs as compared to the pure PVA matrix. This approach to controlling the surface properties of nanofibrous structures with SF may be useful in the design and tailoring of novel matrices for skin regeneration.

  14. The EHV-1 UL4 protein that tempers viral gene expression interacts with cellular transcription factors.

    Science.gov (United States)

    Zhang, Yunfei; Charvat, Robert A; Kim, Seong K; O'Callaghan, Dennis J

    2014-01-20

    The UL4 gene is conserved within the genome of defective interfering particles of equine herpesvirus type 1 (EHV-1) that mediate persistent infection. Here, we show that the UL4 protein inhibits EHV-1 reporter gene expression by decreasing the level of transcribed mRNA. The UL4 protein did not bind any gene class of EHV-1 promoters in electromobility or chromatin immunoprecipitation assays, but directly interacted with the TATA box-binding protein (TBP) and the carboxy-terminal domain of RNA polymerase II both in vitro (GST-pulldown assays) and in infected cells (coimmunoprecipitation analyses). Microarray analyses of the expression of the 78 EHV-1 genes revealed that viral late genes important for virion assembly displayed enhanced expression in cells infected with UL4-null virus as compared to wild-type or UL4-restored EHV-1. Quantitative PCR analyses showed that viral DNA replication was not retarded in cells infected with the UL4-null virus as compared to wild-type EHV-1.

  15. Cloning, characterization and sub-cellular localization of gamma subunit of T-complex protein-1 (chaperonin) from Leishmania donovani

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskar,; Kumari, Neeti [Division of Biochemistry, CSIR-Central Drug Research Institute, Chattar Manzil Palace, PO Box 173, Lucknow (India); Goyal, Neena, E-mail: neenacdri@yahoo.com [Division of Biochemistry, CSIR-Central Drug Research Institute, Chattar Manzil Palace, PO Box 173, Lucknow (India)

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer The study presents cloning and characterization of TCP1{gamma} gene from L. donovani. Black-Right-Pointing-Pointer TCP1{gamma} is a subunit of T-complex protein-1 (TCP1), a chaperonin class of protein. Black-Right-Pointing-Pointer LdTCP{gamma} exhibited differential expression in different stages of promastigotes. Black-Right-Pointing-Pointer LdTCP{gamma} co-localized with actin, a cytoskeleton protein. Black-Right-Pointing-Pointer The data suggests that this gene may have a role in differentiation/biogenesis. Black-Right-Pointing-Pointer First report on this chapronin in Leishmania. -- Abstract: T-complex protein-1 (TCP1) complex, a chaperonin class of protein, ubiquitous in all genera of life, is involved in intracellular assembly and folding of various proteins. The gamma subunit of TCP1 complex (TCP1{gamma}), plays a pivotal role in the folding and assembly of cytoskeleton protein(s) as an individual or complexed with other subunits. Here, we report for the first time cloning, characterization and expression of the TCP1{gamma} of Leishmania donovani (LdTCP1{gamma}), the causative agent of Indian Kala-azar. Primary sequence analysis of LdTCP1{gamma} revealed the presence of all the characteristic features of TCP1{gamma}. However, leishmanial TCP1{gamma} represents a distinct kinetoplastid group, clustered in a separate branch of the phylogenic tree. LdTCP1{gamma} exhibited differential expression in different stages of promastigotes. The non-dividing stationary phase promastigotes exhibited 2.5-fold less expression of LdTCP1{gamma} as compared to rapidly dividing log phase parasites. The sub-cellular distribution of LdTCP1{gamma} was studied in log phase promastigotes by employing indirect immunofluorescence microscopy. The protein was present not only in cytoplasm but it was also localized in nucleus, peri-nuclear region, flagella, flagellar pocket and apical region. Co-localization of LdTCP1{gamma} with actin suggests

  16. Alumina-zirconia composites functionalized with laminin-1 and laminin-5 for dentistry: effect of protein adsorption on cellular response.

    Science.gov (United States)

    Vallée, A; Faga, M G; Mussano, F; Catalano, F; Tolosano, E; Carossa, S; Altruda, F; Martra, G

    2014-02-01

    The present paper describes a study on laminin interaction with the surface of two alumina-zirconia composites with different percentages of ZrO2, both with submicrometric grain size. As major molecules within the basement membrane (BM), laminins are important protein fragments for epithelial cell adhesion and migration. On the other hand, alumina-zirconia composites are very attractive materials for dental applications due to their esthetic and mechanical properties. X-Ray photoelectron spectroscopy and atomic force microscopy were used to study the adsorption of two types of laminin, laminin-1 (Ln-1) and laminin-5 (Ln-5), onto the ceramics surfaces. The in vitro cell response was determined by intracellular phosphorylation of major kinases. Ceramics samples functionalized with laminins showed better cellular activation than untreated specimens; furthermore, cellular activation was found to be greater for the composite with higher percentage in zirconia when functionalized with Ln-5, whereas the adsorption of Ln-1 resulted in a greater activation for the alumina-rich oxide.

  17. Monoacylated Cellular Prion Proteins Reduce Amyloid-β-Induced Activation of Cytoplasmic Phospholipase A2 and Synapse Damage

    Directory of Open Access Journals (Sweden)

    Ewan West

    2015-06-01

    Full Text Available Alzheimer’s disease (AD is a progressive neurodegenerative disease characterized by the accumulation of amyloid-β (Aβ and the loss of synapses. Aggregation of the cellular prion protein (PrPC by Aβ oligomers induced synapse damage in cultured neurons. PrPC is attached to membranes via a glycosylphosphatidylinositol (GPI anchor, the composition of which affects protein targeting and cell signaling. Monoacylated PrPC incorporated into neurons bound “natural Aβ”, sequestering Aβ outside lipid rafts and preventing its accumulation at synapses. The presence of monoacylated PrPC reduced the Aβ-induced activation of cytoplasmic phospholipase A2 (cPLA2 and Aβ-induced synapse damage. This protective effect was stimulus specific, as treated neurons remained sensitive to α-synuclein, a protein associated with synapse damage in Parkinson’s disease. In synaptosomes, the aggregation of PrPC by Aβ oligomers triggered the formation of a signaling complex containing the cPLA2.a process, disrupted by monoacylated PrPC. We propose that monoacylated PrPC acts as a molecular sponge, binding Aβ oligomers at the neuronal perikarya without activating cPLA2 or triggering synapse damage.

  18. Requirement of cellular DDX3 for hepatitis C virus replication is unrelated to its interaction with the viral core protein.

    Science.gov (United States)

    Angus, Allan G N; Dalrymple, David; Boulant, Steeve; McGivern, David R; Clayton, Reginald F; Scott, Martin J; Adair, Richard; Graham, Susan; Owsianka, Ania M; Targett-Adams, Paul; Li, Kui; Wakita, Takaji; McLauchlan, John; Lemon, Stanley M; Patel, Arvind H

    2010-01-01

    The cellular DEAD-box protein DDX3 was recently shown to be essential for hepatitis C virus (HCV) replication. Prior to that, we had reported that HCV core binds to DDX3 in yeast-two hybrid and transient transfection assays. Here, we confirm by co-immunoprecipitation that this interaction occurs in cells replicating the JFH1 virus. Consistent with this result, immunofluorescence staining of infected cells revealed a dramatic redistribution of cytoplasmic DDX3 by core protein to the virus assembly sites around lipid droplets. Given this close association of DDX3 with core and lipid droplets, and its involvement in virus replication, we investigated the importance of this host factor in the virus life cycle. Mutagenesis studies located a single amino acid in the N-terminal domain of JFH1 core that when changed to alanine significantly abrogated this interaction. Surprisingly, this mutation did not alter infectious virus production and RNA replication, indicating that the core-DDX3 interaction is dispensable in the HCV life cycle. Consistent with previous studies, siRNA-led knockdown of DDX3 lowered virus production and RNA replication levels of both WT JFH1 and the mutant virus unable to bind DDX3. Thus, our study shows for the first time that the requirement of DDX3 for HCV replication is unrelated to its interaction with the viral core protein.

  19. Effect of FCCP on tight junction permeability and cellular distribution of ZO-1 protein in epithelial (MDCK) cells.

    Science.gov (United States)

    Li, C X; Poznansky, M J

    1990-12-14

    The effect of the uncoupler of oxidative phosphorylation, FCCP (carbonylcyanide p-trifluoromethoxyphenylhydrazone), on the tight junction of Madin-Darby canine kidney cells was examined. FCCP induced an abrupt decrease in the transepithelial electrical resistance of the confluent monolayers over a period of 20 s. When FCCP was withdrawn from the incubation medium, the monolayer resistance recovered to close to the original level in less than 2 h. Staining of the tight junction-associated protein ZO-1 showed that the changes in transepithelial electrical resistance were accompanied by a diffusing of the protein away from cell peripheries and a reconcentration to the tight junction areas following resistance recovery. Intracellular pH was decreased by FCCP on a similar time-scale with no obvious changes in ATP levels over this time-course. These data suggest that the uncoupler FCCP has a profound effect on tight junction permeability and cellular distribution of the tight junction protein ZO-1 in the epithelial cells and that it probably acts by breaking down proton gradients and altering intracellular pH.

  20. Inhibition of thyrotropin-stimulated DNA synthesis by microinjection of inhibitors of cellular Ras and cyclic AMP-dependent protein kinase.

    Science.gov (United States)

    Kupperman, E; Wen, W; Meinkoth, J L

    1993-08-01

    Microinjection of a dominant interfering mutant of Ras (N17 Ras) caused a significant reduction in thyrotropin (thyroid-stimulating hormone [TSH])-stimulated DNA synthesis in rat thyroid cells. A similar reduction was observed following injection of the heat-stable protein kinase inhibitor of the cyclic AMP-dependent protein kinase. Coinjection of both inhibitors almost completely abolished TSH-induced DNA synthesis. In contrast to TSH, overexpression of cellular Ras protein did not stimulate the expression of a cyclic AMP response element-regulated reporter gene. Similarly, injection of N17 Ras had no effect on TSH-stimulated reporter gene expression. Moreover, overexpression of cellular Ras protein stimulated similar levels of DNA synthesis in the presence or absence of the heat-stable protein kinase inhibitor. Together, these results suggest that in Wistar rat thyroid cells, a full mitogenic response to TSH requires both Ras and cyclic APK-dependent protein kinase.

  1. Ability of CK2beta to selectively regulate cellular protein kinases

    DEFF Research Database (Denmark)

    Olsen, Birgitte; Guerra, Barbara

    2008-01-01

    additional phosphodegrons recognised by beta-TrCP. These events contribute to destabilise Wee1 at the onset of mitosis (Watanabe et al. Proc Natl Acad Sci USA 101:4419-4424, 2004). We show here that in addition to the ability of CK2 to phosphorylate Wee1 as reported earlier, the regulatory beta......-subunit of protein kinase CK2 can interact with Wee1 in high molecular mass complexes. Indirect immunofluorescence microscopy revealled subcellular co-localisation of CK2beta and Wee1 in the nucleus. Moreover, in vitro phosphorylation assays showed that CK2beta indirectly up-regulates the activity of CDK1...

  2. Cellular Activity of New Small Molecule Protein Arginine Deiminase 3 (PAD3) Inhibitors.

    Science.gov (United States)

    Jamali, Haya; Khan, Hasan A; Tjin, Caroline C; Ellman, Jonathan A

    2016-09-08

    The protein arginine deiminases (PADs) catalyze the post-translational deimination of arginine side chains. Multiple PAD isozymes have been characterized, and abnormal PAD activity has been associated with several human disease states. PAD3 has been characterized as a modulator of cell growth via apoptosis inducing factor and has been implicated in the neurodegenerative response to spinal cord injury. Here, we describe the design, synthesis, and evaluation of conformationally constrained versions of the potent and selective PAD3 inhibitor 2. The cell activity of representative inhibitors in this series was also demonstrated for the first time by rescue of thapsigargin-induced cell death in PAD3-expressing HEK293T cells.

  3. Inactivation of Multidrug Resistance Proteins Disrupts Both Cellular Extrusion and Intracellular Degradation of cAMP

    OpenAIRE

    Xie, Moses; Rich, Thomas C.; Scheitrum, Colleen; Conti, Marco; Richter, Wito

    2011-01-01

    In addition to xenobiotics and several other endogenous metabolites, multidrug-resistance proteins (MRPs) extrude the second-messenger cAMP from various cells. Pharmacological and/or genetic inactivation of MRPs has been shown to augment intracellular cAMP signaling, an effect assumed to be a direct consequence of the blockade of cAMP extrusion. Here we provide evidence that the augmented intracellular cAMP levels are not due exclusively to the prevention of cAMP efflux because MRP inactivati...

  4. Prion Protein Modulates Cellular Iron Uptake: A Novel Function with Implications for Prion Disease Pathogenesis

    OpenAIRE

    2009-01-01

    Converging evidence leaves little doubt that a change in the conformation of prion protein (PrP(C)) from a mainly alpha-helical to a beta-sheet rich PrP-scrapie (PrP(Sc)) form is the main event responsible for prion disease associated neurotoxicity. However, neither the mechanism of toxicity by PrP(Sc), nor the normal function of PrP(C) is entirely clear. Recent reports suggest that imbalance of iron homeostasis is a common feature of prion infected cells and mouse models, implicating redox-i...

  5. The telomeric protein AKTIP interacts with A- and B-type lamins and is involved in regulation of cellular senescence

    Science.gov (United States)

    Burla, Romina; Carcuro, Mariateresa; Torre, Mattia La; Fratini, Federica; Crescenzi, Marco; D'Apice, Maria Rosaria; Spitalieri, Paola; Raffa, Grazia Daniela; Astrologo, Letizia; Lattanzi, Giovanna; Cundari, Enrico; Raimondo, Domenico; Biroccio, Annamaria; Gatti, Maurizio

    2016-01-01

    AKTIP is a shelterin-interacting protein required for replication of telomeric DNA. Here, we show that AKTIP biochemically interacts with A- and B-type lamins and affects lamin A, but not lamin C or B, expression. In interphase cells, AKTIP localizes at the nuclear rim and in discrete regions of the nucleoplasm just like lamins. Double immunostaining revealed that AKTIP partially co-localizes with lamin B1 and lamin A/C in interphase cells, and that proper AKTIP localization requires functional lamin A. In mitotic cells, AKTIP is enriched at the spindle poles and at the midbody of late telophase cells similar to lamin B1. AKTIP-depleted cells show senescence-associated markers and recapitulate several aspects of the progeroid phenotype. Collectively, our results indicate that AKTIP is a new player in lamin-related processes, including those that govern nuclear architecture, telomere homeostasis and cellular senescence. PMID:27512140

  6. Use of an Anaerobic Chamber Environment for the Assay of Endogenous Cellular Protein-Tyrosine Phosphatase Activities

    Directory of Open Access Journals (Sweden)

    Zhu Li

    2002-01-01

    Full Text Available Protein-tyrosine phosphatases (PTPases have a catalytic cysteine residue whose reduced state is integral to the reaction mechanism. Since exposure to air can artifactually oxidize this highly reactive thiol, PTPase assays have typically used potent reducing agents to reactivate the enzymes present; however, this approach does not allow for the measurement of the endogenous PTPase activity directly isolated from the in vivo cellular environment. Here we provide a method for using an anaerobic chamber to preserve the activity of the total PTPase complement in a tissue lysate or of an immunoprecipitated PTPase homolog to characterize their endogenous activation state. Comparison with a sample treated with biochemical reducing agents allows the determination of the activatable (reducible fraction of the endogenous PTPase pool.

  7. A role for Alstrom syndrome protein, alms1, in kidney ciliogenesis and cellular quiescence.

    Directory of Open Access Journals (Sweden)

    Guochun Li

    2007-01-01

    Full Text Available Premature truncation alleles in the ALMS1 gene are a frequent cause of human Alström syndrome. Alström syndrome is a rare disorder characterized by early obesity and sensory impairment, symptoms shared with other genetic diseases affecting proteins of the primary cilium. ALMS1 localizes to centrosomes and ciliary basal bodies, but truncation mutations in Alms1/ALMS1 do not preclude formation of cilia. Here, we show that in vitro knockdown of Alms1 in mice causes stunted cilia on kidney epithelial cells and prevents these cells from increasing calcium influx in response to mechanical stimuli. The stunted-cilium phenotype can be rescued with a 5' fragment of the Alms1 cDNA, which resembles disease-associated alleles. In a mouse model of Alström syndrome, Alms1 protein can be stably expressed from the mutant allele and is required for cilia formation in primary cells. Aged mice developed specific loss of cilia from the kidney proximal tubules, which is associated with foci of apoptosis or proliferation. As renal failure is a common cause of mortality in Alström syndrome patients, we conclude that this disease should be considered as a further example of the class of renal ciliopathies: wild-type or mutant alleles of the Alström syndrome gene can support normal kidney ciliogenesis in vitro and in vivo, but mutant alleles are associated with age-dependent loss of kidney primary cilia.

  8. A review of chemical surface modification of bioceramics: effects on protein adsorption and cellular response.

    Science.gov (United States)

    Lee, Wing-Hin; Loo, Ching-Yee; Rohanizadeh, Ramin

    2014-10-01

    Calcium phosphates (CaPs) are ideal biomaterials for bone repair because of the similarities between their chemical structure and the mineral phase of hard biological tissues (e.g., bones and teeth). Since CaP bone grafts exhibit superior biocompatibility and strong osseointegration properties, they have been widely investigated for use as an in situ carrier for delivery of anti-resorptive and osteogenic drugs. The surface properties of CaP govern the affinity and the binding mechanisms between biological macromolecules (e.g., proteins) and the CaP surface, which indirectly determines the interactions between bone cells and implanted CaP biomaterials. These surface properties ultimately play a pivotal role in determining the success of CaP as bone implants and/or drug carriers. This review provides an in-depth discussion of the current methodologies used to regulate the surface chemistry of CaP and their subsequent effects in regards to protein adsorption and delivery, as well as cell/materials interactions.

  9. Proteomic analyses of human cytomegalovirus strain AD169 derivatives reveal highly conserved patterns of viral and cellular proteins in infected fibroblasts.

    Science.gov (United States)

    Reyda, Sabine; Büscher, Nicole; Tenzer, Stefan; Plachter, Bodo

    2014-01-07

    Human cytomegalovirus (HCMV) particle morphogenesis in infected cells is an orchestrated process that eventually results in the release of enveloped virions. Proteomic analysis has been employed to reveal the complexity in the protein composition of these extracellular particles. Only limited information is however available regarding the proteome of infected cells preceding the release of HCMV virions. We used quantitative mass spectrometry to address the pattern of viral and cellular proteins in cells, infected with derivatives of the AD169 laboratory strain. Our analyses revealed a remarkable conservation in the patterns of viral and of abundant cellular proteins in cells, infected for 2 hours, 2 days, or 4 days. Most viral proteins increased in abundance as the infection progressed over time. Of the proteins that were reliably detectable by mass spectrometry, only IE1 (pUL123), pTRS1, and pIRS1 were downregulated at 4 days after infection. In addition, little variation of viral proteins in the virions of the different viruses was detectable, independent of the expression of the major tegument protein pp65. Taken together these data suggest that there is little variation in the expression program of viral and cellular proteins in cells infected with related HCMVs, resulting in a conserved pattern of viral proteins ultimately associated with extracellular virions.

  10. Maintenance of asymmetric cellular localization of an auxin transport protein through interaction with the actin cytoskeleton

    Science.gov (United States)

    Muday, G. K.

    2000-01-01

    In shoots, polar auxin transport is basipetal (that is, from the shoot apex toward the base) and is driven by the basal localization of the auxin efflux carrier complex. The focus of this article is to summarize the experiments that have examined how the asymmetric distribution of this protein complex is controlled and the significance of this polar distribution. Experimental evidence suggests that asymmetries in the auxin efflux carrier may be established through localized secretion of Golgi vesicles, whereas an attachment of a subunit of the efflux carrier to the actin cytoskeleton may maintain this localization. In addition, the idea that this localization of the efflux carrier may control both the polarity of auxin movement and more globally regulate developmental polarity is explored. Finally, evidence indicating that the gravity vector controls auxin transport polarity is summarized and possible mechanisms for the environmentally induced changes in auxin transport polarity are discussed.

  11. Role of Crk Adaptor Proteins in Cellular Migration and Invasion in Human Breast Cancer

    Science.gov (United States)

    2009-03-01

    0.0001349 1.280209 0.00657 cholesterol 25- hydroxylase ZNF539 2.225650467 0.0042638 1.295457 0.03133 zinc finger protein 254 PRSS7 2.233104326 0.0239284...4.98281  6.27E‐07  Toll‐like receptor signaling pathway  ‐3.51463  0.00044  Caprolactam degradation  ‐0.99768  0.318433  Phenylalanine , tyrosine and...Escherichia coli infection – EHEC  ‐1.38214  0.166928  Phenylalanine  metabolism  ‐2.08135  0.037401  Pathogenic Escherichia coli infection – EPEC  ‐0.48134

  12. Signal transduction in neurons: effects of cellular prion protein on fyn kinase and ERK1/2 kinase

    Directory of Open Access Journals (Sweden)

    Tomasi Vittorio

    2010-12-01

    Full Text Available Abstract Background It has been reported that cellular prion protein (PrPc co-localizes with caveolin-1 and participates to signal transduction events by recruiting Fyn kinase. As PrPc is a secreted protein anchored to the outer surface membrane through a glycosylphosphatidylinositol (GPI anchor (secPrP and caveolin-1 is located in the inner leaflet of plasma membrane, there is a problem of how the two proteins can physically interact each other and transduce signals. Results By using the GST-fusion proteins system we observed that PrPc strongly interacts with caveolin-1 scaffolding domain and with a caveolin-1 hydrophilic C-terminal region, but not with the caveolin-1 N-terminal region. In vitro binding experiments were also performed to define the site(s of PrPc interacting with cav-1. The results are consistent with a participation of PrPc octapeptide repeats motif in the binding to caveolin-1 scaffolding domain. The caveolar localization of PrPc was ascertained by co-immunoprecipitation, by co-localization after flotation in density gradients and by confocal microscopy analysis of PrPc and caveolin-1 distributions in a neuronal cell line (GN11 expressing caveolin-1 at high levels. Conclusions We observed that, after antibody-mediated cross-linking or copper treatment, PrPc was internalized probably into caveolae. We propose that following translocation from rafts to caveolae or caveolae-like domains, secPrP could interact with caveolin-1 and induce signal transduction events.

  13. Cellular prion protein controls stem cell-like properties of human glioblastoma tumor-initiating cells

    Science.gov (United States)

    Corsaro, Alessandro; Bajetto, Adriana; Thellung, Stefano; Begani, Giulia; Villa, Valentina; Nizzari, Mario; Pattarozzi, Alessandra; Solari, Agnese; Gatti, Monica; Pagano, Aldo; Würth, Roberto; Daga, Antonio; Barbieri, Federica; Florio, Tullio

    2016-01-01

    Prion protein (PrPC) is a cell surface glycoprotein whose misfolding is responsible for prion diseases. Although its physiological role is not completely defined, several lines of evidence propose that PrPC is involved in self-renewal, pluripotency gene expression, proliferation and differentiation of neural stem cells. Moreover, PrPC regulates different biological functions in human tumors, including glioblastoma (GBM). We analyzed the role of PrPC in GBM cell pathogenicity focusing on tumor-initiating cells (TICs, or cancer stem cells, CSCs), the subpopulation responsible for development, progression and recurrence of most malignancies. Analyzing four GBM CSC-enriched cultures, we show that PrPC expression is directly correlated with the proliferation rate of the cells. To better define its role in CSC biology, we knocked-down PrPC expression in two of these GBM-derived CSC cultures by specific lentiviral-delivered shRNAs. We provide evidence that CSC proliferation rate, spherogenesis and in vivo tumorigenicity are significantly inhibited in PrPC down-regulated cells. Moreover, PrPC down-regulation caused loss of expression of the stemness and self-renewal markers (NANOG, Sox2) and the activation of differentiation pathways (i.e. increased GFAP expression). Our results suggest that PrPC controls the stemness properties of human GBM CSCs and that its down-regulation induces the acquisition of a more differentiated and less oncogenic phenotype. PMID:27229535

  14. Community control in cellular protein production: consequences for amino acid starvation.

    Science.gov (United States)

    Heldt, Frank S; Brackley, Chris A; Grebogi, Celso; Thiel, Marco

    2015-12-13

    Deprivation of essential nutrients can have stark consequences for many processes in a cell. We consider amino acid starvation, which can result in bottlenecks in mRNA translation when ribosomes stall due to lack of resources, i.e. tRNAs charged with the missing amino acid. Recent experiments also show less obvious effects such as increased charging of other (non-starved) tRNA species and selective charging of isoaccepting tRNAs. We present a mechanism which accounts for these observations and shows that production of some proteins can actually increase under starvation. One might assume that such responses could only be a result of sophisticated control pathways, but here we show that these effects can occur naturally due to changes in the supply and demand for different resources, and that control can be accomplished through selective use of rare codons. We develop a model for translation which includes the dynamics of the charging and use of aminoacylated tRNAs, explicitly taking into account the effect of specific codon sequences. This constitutes a new control mechanism in gene regulation which emerges at the community level, i.e. via resources used by all ribosomes.

  15. Extralysosomal turnover of cellular proteins: Targeting substrates in the ubiquitin, ATP-dependent degradation system

    Energy Technology Data Exchange (ETDEWEB)

    Marriott, D.

    1988-01-01

    Calmodulin derived from a cloned chicken gene can be ubiquitinated and degraded by an in vitro reticulocyte lysate system. The chemical reactivity and the surface accessibility of the {epsilon}-amino group on lysine 115 in the calmodulin polypeptide chain were studied by trace labeling with acetic anhydride and with a ubiquitin derivative containing an azido group at the C-terminal glycine residue. Fractionation of reticulocyte lysate proteins separated the activity which degrades the calmodulin moiety of ubiquitin-calmodulin conjugates from that which acts on the isopeptide linkage. Neither of these two activities act on a synthetic isopeptide, which mimics the junction of ubiquitin-calmodulin, indicating the importance of the folding of ubiquitin for recognition. Based on recent findings that the ubiquitin moieties linked to {beta}galactosidase exist as a single multiubiquitin chain, studies were carried out to determine the structure of the ubiquitin-ubiquitin linkage. Ubiquitin was in vivo labeled with ({sup 3}H) and conjugated to {beta}galactosidase. Individual conjugates were isolated and subjected to peptide mapping by trypsin digestion, and tryptic fragments were analyzed of HPLC. The results indicated that the ubiquitin-ubiquitin linkage involves lysine residue 48 in the ubiquitin sequence.

  16. The cellular prion protein negatively regulates phagocytosis and cytokine expression in murine bone marrow-derived macrophages.

    Directory of Open Access Journals (Sweden)

    Min Wang

    Full Text Available The cellular prion protein (PrP(C is a glycosylphosphatidylinositol (GPI-anchored glycoprotein on the cell surface. Previous studies have demonstrated contradictory roles for PrP(C in connection with the phagocytic ability of macrophages. In the present work, we investigated the function of PrP(C in phagocytosis and cytokine expression in bone marrow-derived macrophages infected with Escherichia coli. E. coli infection induced an increase in the PRNP mRNA level. Knockout of PrP(C promoted bacterial uptake; upregulated Rab5, Rab7, and Eea1 mRNA expression; and increased the recruitment of lysosomal-associated membrane protein-2 to phagosomes, suggesting enhanced microbicidal activity. Remarkably, knockout of PrP(C suppressed the proliferation of internalized bacteria and increased the expression of cytokines such as interleukin-1β. Collectively, our data reveal an important role of PrP(C as a negative regulator for phagocytosis, phagosome maturation, cytokine expression, and macrophage microbicidal activity.

  17. Bovine spongiform encephalopathy induces misfolding of alleged prion-resistant species cellular prion protein without altering its pathobiological features.

    Science.gov (United States)

    Vidal, Enric; Fernández-Borges, Natalia; Pintado, Belén; Ordóñez, Montserrat; Márquez, Mercedes; Fondevila, Dolors; Torres, Juan María; Pumarola, Martí; Castilla, Joaquín

    2013-05-01

    Bovine spongiform encephalopathy (BSE) prions were responsible for an unforeseen epizootic in cattle which had a vast social, economic, and public health impact. This was primarily because BSE prions were found to be transmissible to humans. Other species were also susceptible to BSE either by natural infection (e.g., felids, caprids) or in experimental settings (e.g., sheep, mice). However, certain species closely related to humans, such as canids and leporids, were apparently resistant to BSE. In vitro prion amplification techniques (saPMCA) were used to successfully misfold the cellular prion protein (PrP(c)) of these allegedly resistant species into a BSE-type prion protein. The biochemical and biological properties of the new prions generated in vitro after seeding rabbit and dog brain homogenates with classical BSE were studied. Pathobiological features of the resultant prion strains were determined after their inoculation into transgenic mice expressing bovine and human PrP(C). Strain characteristics of the in vitro-adapted rabbit and dog BSE agent remained invariable with respect to the original cattle BSE prion, suggesting that the naturally low susceptibility of rabbits and dogs to prion infections should not alter their zoonotic potential if these animals became infected with BSE. This study provides a sound basis for risk assessment regarding prion diseases in purportedly resistant species.

  18. Expression of cellular FLICE-inhibitory protein and its association with p53 mutation in colon cancer

    Institute of Scientific and Technical Information of China (English)

    Xiao-Dong Zhou; Jie-Ping Yu; Hong-Xia Chen; Hong-Gang Yu; He-Sheng Luo

    2005-01-01

    AIM: To investigate the expression of cellular FLICE (Fas associated death domain-like IL-1beta-converting enzyme)-inhibitory protein (c-FLIP) and its association with p53mutation in colon cancer.METHODS: Immunohistochemical staining of c-FLIP and mutant p53 by using specific antibodies was performed by the standard streptavidin-peroxidase technique for 45 colon cancer tissue samples with matched normal tissues. Semi-quantitative reverse transcriptional (RT)-PCR was used to measure c-FLIP mRNA levels. t-test statistical method was used in data analyses.RESULTS: c-FLIP mRNA was expressed in all colon cancer tissues and its level (0.63±0.12) was significantly higher than that in normal tissues (0.38±0.10, P<0.01). Immunohistochemically, c-FLIP protein was also expressed in all colon cancers (45/45) and 71.1% (32/45) showed an intense immunostaining, in contrast, 93.3% (42/45) of normal colonic mucosa showed positive staining and none of them immunostained intensely. The quantity of c-FLIP protein was significantly higher in cancer tissues than in normal mucosa (7.04±1.20 vs 5.21±0.86, P<0.01).Positive staining of mutant p53 protein was found in 60%(27/45) colon cancers. c-FLIP mRNA level was decreased in p53 positive group compared with p53 negative cancer tissues (0.59±0.13 vs 0.69±0.14, P<0.01), but c-FLIP protein had a significantly higher level in p53 positive cancer tissues than in negative ones (7.57±1.30 vs 6.25±1.27,P<0.01).CONCLUSION: c-FLIP is specially overexpressed in colon cancers and it might contribute to carcinogenesis of normal colonic mucosa. p53 may exert transcriptional upregulation effects on c-FLIP gene and more potent effects on promoting the degradation of c-FLIP protein.

  19. The effect of oxidant and the non-oxidant alteration of cellular thiol concentration on the formation of protein mixed-disulfides in HEK 293 cells.

    Directory of Open Access Journals (Sweden)

    Jasen Lee Gilge

    Full Text Available Cellular molecules possess various mechanisms in responding to oxidant stress. In terms of protein responses, protein S-glutathionylation is a unique post-translational modification of protein reactive cysteines forming disulfides with glutathione molecules. This modification has been proposed to play roles in antioxidant, regulatory and signaling in cells under oxidant stress. Recently, the increased level of protein S-glutathionylation has been linked with the development of diseases. In this report, specific S-glutathionylated proteins were demonstrated in human embryonic kidney 293 cells treated with two different oxidative reagents: diamide and hydrogen peroxide. Diamide is a chemical oxidizing agent whereas hydrogen peroxide is a physiological oxidant. Under the experimental conditions, these two oxidants decreased glutathione concentration without toxicity. S-glutathionylated proteins were detected by immunoblotting and glutathione concentrations were determined by high performance liquid chromatography. We further show the effect of alteration of the cellular thiol pool on the amount of protein S-glutathionylation in oxidant-treated cells. Cellular thiol concentrations were altered either by a specific way using buthionine sulfoximine, a specific inhibitor of glutathione biosynthesis or by a non-specific way, incubating cells in cystine-methionine deficient media. Cells only treated with either buthionine sulfoximine or cystine-methionine deficient media did not induce protein S-glutathionylation, even though both conditions decreased 65% of cellular glutathione. Moreover, the amount of protein S-glutathionylation under both conditions in the presence of oxidants was not altered when compared to the amount observed in regular media with oxidants present. Protein S-glutathionylation is a dynamic reaction which depends on the rate of adding and removing glutathione. Phenylarsine oxide, which specifically forms a covalent adduct with

  20. TRIM32 protein modulates type I interferon induction and cellular antiviral response by targeting MITA/STING protein for K63-linked ubiquitination.

    Science.gov (United States)

    Zhang, Jing; Hu, Ming-Ming; Wang, Yan-Yi; Shu, Hong-Bing

    2012-08-17

    Viral infection activates several transcription factors including NF-κB and IRF3, which collaborate to induce type I interferons (IFNs) and innate antiviral response. MITA (also called STING) is a critical adaptor protein that links virus-sensing receptors to IRF3 activation upon infection by both RNA and DNA pathogens. Here we show that the E3 ubiquitin ligase tripartite motif protein 32 (TRIM32) ubiquitinated MITA and dramatically enhanced MITA-mediated induction of IFN-β. Overexpression of TRIM32 potentiated virus-triggered IFNB1 expression and cellular antiviral response. Consistently, knockdown of TRIM32 had opposite effects. TRIM32 interacted with MITA, and was located at the mitochondria and endoplasmic reticulum. TRIM32 targeted MITA for K63-linked ubiquitination at K20/150/224/236 through its E3 ubiquitin ligase activity, which promoted the interaction of MITA with TBK1. These findings suggest that TRIM32 is an important regulatory protein for innate immunity against both RNA and DNA viruses by targeting MITA for K63-linked ubiquitination and downstream activation.

  1. Cellular Signaling Mediated by Prion Protein%PrP~C介导的细胞信号转导

    Institute of Scientific and Technical Information of China (English)

    李晓丽; 高晨; 董小平

    2009-01-01

    The pathogenesis of prion disease is due to misfolding of the cellular prion protein(PrP~C)into a pathogenic isoform(PrP~(Sc)).Although biological functions of PrPC are still unclear,it is assumed that PrP~C plays an important role in copper metabolism,lipoid absorption and cell signal mediation.In addition,PrP~C can interact with caveolin-1 to activate Fyn and act as a receptor to activate cAMP/PKA through interacting with PrP~C-bound peptides and cellular signaling pathways by changing the level of intracellular calcium.%朊病毒病的发生是由于细胞正常朊蛋白PrP~C转变成了异常构象的PrP~(Sc)形式.PrP~C 的生理学功能目前尚不完全明确,可能与铜离子代谢、脂质摄取以及细胞信号传递有关.PrP~C可以与小窝蛋白相互作用而活化Fyn非受体酪氨酸激酶从而引起下游信号通路的转导;可以作为受体与PrP~C键合多肽结合后激活cAMP/PKA信号通路;以及引起细胞内钙离子浓度变化而活化信号通路.

  2. Characterization and sub-cellular localization of GalNAc-binding proteins isolated from human hepatic stellate cells.

    Science.gov (United States)

    Zhong, Yaogang; Zhang, Jing; Yu, Hanjie; Zhang, Jiaxu; Sun, Xiu-Xuan; Chen, Wentian; Bian, Huijie; Li, Zheng

    2015-12-25

    Although the expression levels of total GalNAc-binding proteins (GNBPs) were up-regulated significantly in human hepatic stellate cells (HSCs) activated with transforming growth factor-β1(TGF-β1), yet little is known about the precise types, distribution and sub-cellular localization of the GNBPs in HSCs. Here, 264 GNBPs from the activated HSCs and 257 GNBPs from the quiescent HSCs were identified and annotated. A total of 46 GNBPs were estimated to be significantly up-regulated and 40 GNBPs were estimated to be significantly down-regulated in the activated HSCs. For example, the GNBPs (i.e. BTF3, COX17, and ATP5A1) responsible for the regulation of protein binding were up-regulated, and those (i.e. FAM114A1, ENO3, and TKT) responsible for the regulation of protein binding were down-regulated in the activated HSCs. The motifs of the isolated GNBPs showed that Proline residue had the maximum preference in consensus sequences. The western blotting showed the expression levels of COX17, and PRMT1 were significantly up-regulated, while, the expression level of CLIC1(B5) was down-regulated in the activated HSCs and liver cirrhosis tissues. Moreover, the GNBPs were sub-localized in the Golgi apparatus of HSCs. In conclusion, the precision alteration of the GNBPs referred to pathological changes in liver fibrosis/cirrhosis may provide useful information to find new molecular mechanism of HSC activation and discover the biomarkers for diagnosis of liver fibrosis/cirrhosis as well as development of new anti-fibrotic strategies.

  3. Cellular mechanisms by which oxytocin mediates ovine endometrial prostaglandin F2alpha synthesis: role of G(i) proteins and mitogen-activated protein kinases.

    Science.gov (United States)

    Burns, P D; Mendes, J O; Yemm, R S; Clay, C M; Nelson, S E; Hayes, S H; Silvia, W J

    2001-10-01

    Oxytocin stimulates a rapid increase in ovine endometrial prostaglandin (PG) F2alpha synthesis. The overall objective of these experiments was to investigate the cellular mechanisms by which oxytocin induces endometrial PGF2alpha synthesis. The objective of experiment 1 was to determine whether G(i) proteins mediate oxytocin-induced PGF2alpha synthesis. Uteri were collected from four ovary-intact ewes on Day 14 postestrus. Caruncular endometrial explants were dissected and subjected to in vitro incubation. Pertussis toxin, an inhibitor of G(i) proteins, had no effect on the ability of oxytocin to induce PGF2alpha synthesis (P > 0.10). The objective of experiment 2 was to determine whether any of the three mitogen-activated protein kinases (MAPKs), extracellular signal regulated protein kinase (ERK1/2), c-Jun N-terminal/stress-activated protein kinase (JNK/SAPK), or p38 MAPK, mediate oxytocin-induced PGF(2alpha) synthesis. Eleven ovary-intact ewes were given an injection of oxytocin (10 IU; i.v.; n = 5) or physiological saline (i.v.; n = 6) on Day 15 postestrus. Uteri were collected 15 min after injection and caruncular endometrium was dissected. Endometrial homogenates were prepared and subjected to Western blotting. Membranes were probed for both total and phosphorylated forms of all three classes of MAPK. All classes of MAPK were detected in ovine endometrium, but oxytocin treatment had no effect on the expression of these proteins (P > 0.10). ERK1/2 was the only phosphorylated MAPK detected and its concentrations were higher in oxytocin-treated ewes (P Day 14 postestrus. Caruncular endometrial explants were dissected and subjected to in vitro incubation. PD98059, a specific inhibitor of ERK1/2 activity, blocked the ability of oxytocin to stimulate PGF(2alpha synthesis in a dose-dependent manner (P < 0.05). These results indicate that the ovine oxytocin receptor is not coupled to G(i) proteins. These results indicate that oxytocin induces phosphorylation of ERK1

  4. Distribution of dipeptide repeat proteins in cellular models and C9orf72 mutation cases suggests link to transcriptional silencing.

    Science.gov (United States)

    Schludi, Martin H; May, Stephanie; Grässer, Friedrich A; Rentzsch, Kristin; Kremmer, Elisabeth; Küpper, Clemens; Klopstock, Thomas; Arzberger, Thomas; Edbauer, Dieter

    2015-10-01

    A massive expansion of a GGGGCC repeat upstream of the C9orf72 coding region is the most common known cause of amyotrophic lateral sclerosis and frontotemporal dementia. Despite its intronic localization and lack of a canonical start codon, both strands are translated into aggregating dipeptide repeat (DPR) proteins: poly-GA, poly-GP, poly-GR, poly-PR and poly-PA. To address conflicting findings on the predominant toxicity of the different DPR species in model systems, we compared the expression pattern of the DPR proteins in rat primary neurons and postmortem brain and spinal cord of C9orf72 mutation patients. Only poly-GA overexpression closely mimicked the p62-positive neuronal cytoplasmic inclusions commonly observed for all DPR proteins in patients. In contrast, overexpressed poly-GR and poly-PR formed nucleolar p62-negative inclusions. In patients, most of the less common neuronal intranuclear DPR inclusions were para-nucleolar and p62 positive. Neuronal nucleoli in C9orf72 cases showed normal size and morphology regardless of the presence of poly-GR and poly-PR inclusions arguing against widespread nucleolar stress, reported in cellular models. Colocalization of para-nucleolar DPR inclusions with heterochromatin and a marker of transcriptional repression (H3K9me2) indicates a link to gene transcription. In contrast, we detected numerous intranuclear DPR inclusions not associated with nucleolar structures in ependymal and subependymal cells. In patients, neuronal inclusions of poly-GR, poly-GP and the poly-GA interacting protein Unc119 were less abundant than poly-GA inclusions, but showed similar regional and subcellular distribution. Regardless of neurodegeneration, all inclusions were most abundant in neocortex, hippocampus and thalamus, with few inclusions in brain stem and spinal cord. In the granular cell layer of the cerebellum, poly-GA and Unc119 inclusions were significantly more abundant in cases with FTLD than in cases with MND and FTLD/MND. Poly

  5. Localization of the cellular retinoic acid binding protein (CRABP) gene relative to the acute promyelocytic leukemia-associated breakpoint on human chromosome 15

    NARCIS (Netherlands)

    A.H.M. Geurts van Kessel (Ad); H. de Leeuw (H.); E.J. Dekker (E.); J.M. Rijks (Jolianne); N. Spurr (N.); A.M. Ledbetter (Andrew M.); E. Kootwijk (E.); M.J. Vaessen (Marie-Josée)

    1991-01-01

    textabstractA human genomic fragment comprising the cellular retinoic acid binding protein (CRABP) gene was isolated. By using a panel of somatic cell hybrids, this gene could be assigned to human chromosome 15. Subsequently, a possible involvement of the CRABP gene in translocation (15;17) (q22;q11

  6. GCK-MODY diabetes as a protein misfolding disease: the mutation R275C promotes protein misfolding, self-association and cellular degradation.

    Science.gov (United States)

    Negahdar, Maria; Aukrust, Ingvild; Molnes, Janne; Solheim, Marie H; Johansson, Bente B; Sagen, Jørn V; Dahl-Jørgensen, Knut; Kulkarni, Rohit N; Søvik, Oddmund; Flatmark, Torgeir; Njølstad, Pål R; Bjørkhaug, Lise

    2014-01-25

    GCK-MODY, dominantly inherited mild hyperglycemia, is associated with more than 600 mutations in the glucokinase gene. Different molecular mechanisms have been shown to explain GCK-MODY. Here, we report a Pakistani family harboring the glucokinase mutation c.823C>T (p.R275C). The recombinant and in cellulo expressed mutant pancreatic enzyme revealed slightly increased enzyme activity (kcat) and normal affinity for α-D-glucose, and resistance to limited proteolysis by trypsin comparable with wild-type. When stably expressed in HEK293 cells and MIN6 β-cells (at different levels), the mutant protein appeared misfolded and unstable with a propensity to form dimers and aggregates. Its degradation rate was increased, involving the lysosomal and proteasomal quality control systems. On mutation, a hydrogen bond between the R275 side-chain and the carbonyl oxygen of D267 is broken, destabilizing the F260-L271 loop structure and the protein. This promotes the formation of dimers/aggregates and suggests that an increased cellular degradation is the molecular mechanism by which R275C causes GCK-MODY.

  7. Protease resistance of infectious prions is suppressed by removal of a single atom in the cellular prion protein

    Science.gov (United States)

    Hornemann, Simone; Herrmann, Uli Simon; Zhu, Caihong; Dametto, Paolo; Li, Bei; Laferriere, Florent; Polymenidou, Magdalini; Pelczar, Pawel; Schwarz, Petra; Rushing, Elisabeth Jane; Wüthrich, Kurt; Aguzzi, Adriano

    2017-01-01

    Resistance to proteolytic digestion has long been considered a defining trait of prions in tissues of organisms suffering from transmissible spongiform encephalopathies. Detection of proteinase K-resistant prion protein (PrPSc) still represents the diagnostic gold standard for prion diseases in humans, sheep and cattle. However, it has become increasingly apparent that the accumulation of PrPSc does not always accompany prion infections: high titers of prion infectivity can be reached also in the absence of protease resistant PrPSc. Here, we describe a structural basis for the phenomenon of protease-sensitive prion infectivity. We studied the effect on proteinase K (PK) resistance of the amino acid substitution Y169F, which removes a single oxygen atom from the β2–α2 loop of the cellular prion protein (PrPC). When infected with RML or the 263K strain of prions, transgenic mice lacking wild-type (wt) PrPC but expressing MoPrP169F generated prion infectivity at levels comparable to wt mice. The newly generated MoPrP169F prions were biologically indistinguishable from those recovered from prion-infected wt mice, and elicited similar pathologies in vivo. Surprisingly, MoPrP169F prions showed greatly reduced PK resistance and density gradient analyses showed a significant reduction in high-density aggregates. Passage of MoPrP169F prions into mice expressing wt MoPrP led to full recovery of protease resistance, indicating that no strain shift had taken place. We conclude that a subtle structural variation in the β2–α2 loop of PrPC affects the sensitivity of PrPSc to protease but does not impact prion replication and infectivity. With these findings a specific structural feature of PrPC can be linked to a physicochemical property of the corresponding PrPSc. PMID:28207746

  8. Extra-cellular matrix proteins induce matrix metalloproteinase-1 (MMP-1 activity and increase airway smooth muscle contraction in asthma.

    Directory of Open Access Journals (Sweden)

    Natasha K Rogers

    Full Text Available Airway remodelling describes the histopathological changes leading to fixed airway obstruction in patients with asthma and includes extra-cellular matrix (ECM deposition. Matrix metalloproteinase-1 (MMP-1 is present in remodelled airways but its relationship with ECM proteins and the resulting functional consequences are unknown. We used airway smooth muscle cells (ASM and bronchial biopsies from control donors and patients with asthma to examine the regulation of MMP-1 by ECM in ASM cells and the effect of MMP-1 on ASM contraction. Collagen-I and tenascin-C induced MMP-1 protein expression, which for tenascin-C, was greater in asthma derived ASM cells. Tenascin-C induced MMP-1 expression was dependent on ERK1/2, JNK and p38 MAPK activation and attenuated by function blocking antibodies against the β1 and β3 integrin subunits. Tenascin-C and MMP-1 were not expressed in normal airways but co-localised in the ASM bundles and reticular basement membrane of patients with asthma. Further, ECM from asthma derived ASM cells stimulated MMP-1 expression to a greater degree than ECM from normal ASM. Bradykinin induced contraction of ASM cells seeded in 3D collagen gels was reduced by the MMP inhibitor ilomastat and by siRNA knockdown of MMP-1. In summary, the induction of MMP-1 in ASM cells by tenascin-C occurs in part via integrin mediated MAPK signalling. MMP-1 and tenascin-C are co-localised in the smooth muscle bundles of patients with asthma where this interaction may contribute to enhanced airway contraction. Our findings suggest that ECM changes in airway remodelling via MMP-1 could contribute to an environment promoting greater airway narrowing in response to broncho-constrictor stimuli and worsening asthma symptoms.

  9. Cellular localization of Y-box binding protein 1 in brain tissue of rats, macaques, and humans

    Directory of Open Access Journals (Sweden)

    Horn Anja

    2009-03-01

    Full Text Available Abstract Background The Y-box binding protein 1 (YB-1 is considered to be one of the key regulators of transcription and translation. However, so far only limited knowledge exists regarding its cellular distribution in the adult brain. Results Analysis of YB-1 immunolabelling as well as double-labelling with the neuronal marker NeuN in rat brain tissue revealed a predominant neuronal expression in the dentate gyrus, the cornu ammonis pyramidal cell layer, layer III of the piriform cortex as well as throughout all layers of the parahippocampal cortex. In the hilus of the hippocampus single neurons expressed YB-1. The neuronal expression pattern was comparable in the hippocampus and parahippocampal cortex of adult macaques and humans. Double-labelling of YB-1 with the endothelial cell marker Glut-1, the multidrug transporter P-glycoprotein, and the astrocytic marker GFAP did not indicate a co-localization. Following status epilepticus in rats, no induction of YB-1 occurred in brain capillary endothelial cells and neurons. Conclusion In conclusion, our study demonstrates that YB-1 is predominantly expressed in neurons in the adult brain of rats, macaques and humans. Lack of a co-localization with Glut-1 and P-glycoprotein argues against a direct role of YB-1 in the regulation of blood-brain barrier P-glycoprotein.

  10. Oma1 Links Mitochondrial Protein Quality Control and TOR Signaling To Modulate Physiological Plasticity and Cellular Stress Responses.

    Science.gov (United States)

    Bohovych, Iryna; Kastora, Stavroula; Christianson, Sara; Topil, Danelle; Kim, Heejeong; Fangman, Teresa; Zhou, You J; Barrientos, Antoni; Lee, Jaekwon; Brown, Alistair J P; Khalimonchuk, Oleh

    2016-09-01

    A network of conserved proteases known as the intramitochondrial quality control (IMQC) system is central to mitochondrial protein homeostasis and cellular health. IMQC proteases also appear to participate in establishment of signaling cues for mitochondrion-to-nucleus communication. However, little is known about this process. Here, we show that in Saccharomyces cerevisiae, inactivation of the membrane-bound IMQC protease Oma1 interferes with oxidative-stress responses through enhanced production of reactive oxygen species (ROS) during logarithmic growth and reduced stress signaling via the TORC1-Rim15-Msn2/Msn4 axis. Pharmacological or genetic prevention of ROS accumulation in Oma1-deficient cells restores this defective TOR signaling. Additionally, inactivation of the Oma1 ortholog in the human fungal pathogen Candida albicans also alters TOR signaling and, unexpectedly, leads to increased resistance to neutrophil killing and virulence in the invertebrate animal model Galleria mellonella Our findings reveal a novel and evolutionarily conserved link between IMQC and TOR-mediated signaling that regulates physiological plasticity and pancellular oxidative-stress responses.

  11. Decreased PARP and procaspase-2 protein levels are associated with cellular drug resistance in childhood acute lymphoblastic leukemia.

    Science.gov (United States)

    Holleman, Amy; den Boer, Monique L; Kazemier, Karin M; Beverloo, H Berna; von Bergh, Anne R M; Janka-Schaub, Gritta E; Pieters, Rob

    2005-09-01

    Drug resistance in childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is associated with impaired ability to induce apoptosis. To elucidate causes of apoptotic defects, we studied the protein expression of Apaf-1, procaspases-2, -3, -6, -7, -8, -10, and poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) in cells from children with acute lymphoblastic leukemia (ALL; n = 43) and acute myeloid leukemia (AML; n = 10). PARP expression was present in all B-lineage samples, but absent in 4 of 15 T-lineage ALL samples and 3 of 10 AML cases, which was not caused by genomic deletions. PARP expression was a median 7-fold lower in T-lineage ALL (P < .001) and 10-fold lower in AML (P < .001) compared with B-lineage ALL. PARP expression was 4-fold lower in prednisolone, vincristine and L-asparaginase (PVA)-resistant compared with PVA-sensitive ALL patients (P < .001). Procaspase-2 expression was 3-fold lower in T-lineage ALL (P = .022) and AML (P = .014) compared with B-lineage ALL. In addition, procaspase-2 expression was 2-fold lower in PVA-resistant compared to PVA-sensitive ALL patients (P = .042). No relation between apoptotic protease-activating factor 1 (Apaf-1), procaspases-3, -6, -7, -8, -10, and drug resistance was found. In conclusion, low baseline expression of PARP and procaspase-2 is related to cellular drug resistance in childhood acute lymphoblastic leukemia.

  12. The synthesis and characterization of cellular membrane affinity chromatography columns for the study of human multidrug resistant proteins MRP1, MRP2 and human breast cancer resistant protein BCRP using membranes obtained from Spodoptera frugiperda (Sf9) insect cells

    OpenAIRE

    Bhatia, Prateek A.; Moaddel, Ruin; Wainer, Irving W.

    2010-01-01

    CMAC (cellular membrane affinity chromatography columns) have been developed for the study of the human multidrug transporters MRP1, MRP2 and the breast cancer resistance protein (BCRP). The columns were constructed using the immobilized artificial membrane (IAM) stationary phase and cellular membrane fragments obtained from Spodopetra frugiperda (Sf9) cells that had been stably transfected with human Mrp1, Mrp2 or Bcrp c-DNA, using a baculovirus expression system. The resulting CMAC(Sf9MRP1)...

  13. The cellular prion protein interacts with the tissue non-specific alkaline phosphatase in membrane microdomains of bioaminergic neuronal cells.

    Directory of Open Access Journals (Sweden)

    Myriam Ermonval

    Full Text Available BACKGROUND: The cellular prion protein, PrP(C, is GPI anchored and abundant in lipid rafts. The absolute requirement of PrP(C in neurodegeneration associated to prion diseases is well established. However, the function of this ubiquitous protein is still puzzling. Our previous work using the 1C11 neuronal model, provided evidence that PrP(C acts as a cell surface receptor. Besides a ubiquitous signaling function of PrP(C, we have described a neuronal specificity pointing to a role of PrP(C in neuronal homeostasis. 1C11 cells, upon appropriate induction, engage into neuronal differentiation programs, giving rise either to serotonergic (1C11(5-HT or noradrenergic (1C11(NE derivatives. METHODOLOGY/PRINCIPAL FINDINGS: The neuronal specificity of PrP(C signaling prompted us to search for PrP(C partners in 1C11-derived bioaminergic neuronal cells. We show here by immunoprecipitation an association of PrP(C with an 80 kDa protein identified by mass spectrometry as the tissue non-specific alkaline phosphatase (TNAP. This interaction occurs in lipid rafts and is restricted to 1C11-derived neuronal progenies. Our data indicate that TNAP is implemented during the differentiation programs of 1C11(5-HT and 1C11(NE cells and is active at their cell surface. Noteworthy, TNAP may contribute to the regulation of serotonin or catecholamine synthesis in 1C11(5-HT and 1C11(NE bioaminergic cells by controlling pyridoxal phosphate levels. Finally, TNAP activity is shown to modulate the phosphorylation status of laminin and thereby its interaction with PrP. CONCLUSION/SIGNIFICANCE: The identification of a novel PrP(C partner in lipid rafts of neuronal cells favors the idea of a role of PrP in multiple functions. Because PrP(C and laminin functionally interact to support neuronal differentiation and memory consolidation, our findings introduce TNAP as a functional protagonist in the PrP(C-laminin interplay. The partnership between TNAP and PrP(C in neuronal cells may

  14. Genes encoding Cher-TPR fusion proteins are predominantly found in gene clusters encoding chemosensory pathways with alternative cellular functions.

    Science.gov (United States)

    Muñoz-Martínez, Francisco; García-Fontana, Cristina; Rico-Jiménez, Miriam; Alfonso, Carlos; Krell, Tino

    2012-01-01

    Chemosensory pathways correspond to major signal transduction mechanisms and can be classified into the functional families flagellum-mediated taxis, type four pili-mediated taxis or pathways with alternative cellular functions (ACF). CheR methyltransferases are core enzymes in all of these families. CheR proteins fused to tetratricopeptide repeat (TPR) domains have been reported and we present an analysis of this uncharacterized family. We show that CheR-TPRs are widely distributed in GRAM-negative but almost absent from GRAM-positive bacteria. Most strains contain a single CheR-TPR and its abundance does not correlate with the number of chemoreceptors. The TPR domain fused to CheR is comparatively short and frequently composed of 2 repeats. The majority of CheR-TPR genes were found in gene clusters that harbor multidomain response regulators in which the REC domain is fused to different output domains like HK, GGDEF, EAL, HPT, AAA, PAS, GAF, additional REC, HTH, phosphatase or combinations thereof. The response regulator architectures coincide with those reported for the ACF family of pathways. Since the presence of multidomain response regulators is a distinctive feature of this pathway family, we conclude that CheR-TPR proteins form part of ACF type pathways. The diversity of response regulator output domains suggests that the ACF pathways form a superfamily which regroups many different regulatory mechanisms, in which all CheR-TPR proteins appear to participate. In the second part we characterize WspC of Pseudomonas putida, a representative example of CheR-TPR. The affinities of WspC-Pp for S-adenosylmethionine and S-adenosylhomocysteine were comparable to those of prototypal CheR, indicating that WspC-Pp activity is in analogy to prototypal CheRs controlled by product feed-back inhibition. The removal of the TPR domain did not impact significantly on the binding constants and consequently not on the product feed-back inhibition. WspC-Pp was found to be

  15. 肺癌化疗患者早期肾损伤时血清CysC、RBP浓度的变化*%Measurement of Serum Cystatin C and Retinol-binding Protein as Renal Function Evaluation Indicators in Lung Cancer Patients during the Induction Phase of Chemotherapy

    Institute of Scientific and Technical Information of China (English)

    肖憬; 詹翔; 桑圣刚

    2013-01-01

    Objective:To evaluate the value of serum CysC and RBP to detect chemotherapy-induced early renal dysfunction in patients with lung cancer.Method:The concentration of surme CysC or RBP were detected in 32 cases of lung cancer chemotherapy by immune turbidimetry at first and second cycle in first course of treatment,simultaneously,the serum creatinine and blood urea nitrogen were determined and 100 healthy subjects were enrolled as control group.Result:After two cycles of chemotherapy,the concentrations of CysC were obviously higher than before chemotherapy and control group(P0.05).The levels of BUN and Crea were only slightly higher after the second cycle of chemotherapy,the difference between before chemotherapy and control group were significant difference(P0.05).BUN、Crea水平仅在化疗后第二周期略有升高,与化疗前和对照组相比差异有统计学意义(P<0.01);与第一周期同期相比差异有统计学意义(P<0.05).经直线相关性分析显示:CysC和RBP含量变化与eGFR呈负相关(P<0.05).结论:与正常对照相比,化疗诱发早期肾损伤的患者其血清CysC和RBP浓度明显升高,检测血清CysC和RBP浓度有助于化疗诱发早期肾损伤的诊断,具有较高的临床应用价值.

  16. Influência da resposta inflamatória de fase aguda nos níveis séricos de retinol e da proteína de ligação do retinol em pacientes com AIDS Influence of acute-phase inflammatory response on serum levels of retinol and retinol binding protein in HIV/AIDS patients

    OpenAIRE

    Fábio Fernandes Neves; José Fernando de Castro Figueiredo; Alceu Afonso Jordão Júnior; Hélio Vannucchi

    2010-01-01

    INTRODUÇÃO: a hiporretinolemia constitui fator prognóstico independente em pacientes com AIDS, e a atividade inflamatória causa redução dos níveis séricos deste nutriente na população em geral. Entretanto, faltam estudos que avaliem o impacto da atividade inflamatória sobre o nível sérico do retinol em pacientes com AIDS. MÉTODOS: foram avaliados transversalmente 41 pacientes internados por complicações da AIDS, que tiveram quantificados alguns marcadores de inflamação (proteína C reativa e f...

  17. Change and clinical significance of serum retinol-binding protein 4 level in patients with nonalcoholic fatty liver disease%非酒精性脂肪肝患者血清视黄醇结合蛋白4的变化及意义

    Institute of Scientific and Technical Information of China (English)

    张洪梅; 许华强; 丁俊蓉; 杨燕燕; 董红旗

    2009-01-01

    7、0.361、0.387、0.259、0.366、0.342、0.338、0.379,P<0.01).结论 非酒精性脂肪肝患者血清RBP4水平升高,且与HOMA-IR呈正相关,提示RBP4在IR的发展中可能起一定的作用.%levels are elevated in patients with NAFL and correlated with HOMA-IR, suggesting RBP4 may participate in the development of IR and NAFL.

  18. 肥胖及2型糖尿病患者脂肪组织视黄醇结合蛋白4 mRNA的表达及调控%Expression and regulation of retinol binding protein 4 mRNA in human adipose tissue in obese and type 2 diabetics

    Institute of Scientific and Technical Information of China (English)

    刘晓华; 魏丽; 王玲艳; 祝超瑜; 包玉倩; 贾伟平

    2010-01-01

    Objective To study the RBP4 mRNA expression between subcutaneous and visceral adipose tissue in obese and type 2 diabetic patients and to investigate the factors that influence RBP4 mRNA expression in Human visceral adipose tissue. Methods 9 individuals with normal weight normal glucose regulation subjects, 9 obesity subjects and 9 type 2 diabetes subjects were enrolled. All of the subjects were prepared to undergone an operation because of nondiabetes disease. Subcutaneous and visceral adipose tissue were taken out as soon as cultured. RT-PCR and Real-time PCR were used to assay the relative expression of RBP4 mRNA. Results RBP4 mRNA level in visceral adipose tissue of obesity group was (2. 10 ± 1.84),and that of type 2 diabetes group was ( 1.54 ± 0. 46 ), both were significantly higher than that in normal weight normal glucose group ( 0. 75 ± 0. 28, P < 0. 01 , P < 0. 05 ). RBP4 mRNA level in subcutaneous adipose tissue of the three groups were ( 1.05 ±0. 15 vs 0. 99 ±0. 14 vs 1.13 ±0. 07), no difference among them(P > 0. 05 ). Insulin, dexamethasone, pioglitazone, free fatty acids can significantly increase RBP4 mRNA expression, compared with the control group, respectively, have an increase of 2. 13 times, 0. 84times, 2. 04 times, 4. 88 times; however, tumor necrosis factor-αt can significantly lower RBP4 mRNA level, compared with the control group decreased by 38%. Conclusion RBP4 mRNA expression in visceral adipose tissue were significantly higher in obesity and type 2 diabetes subjects. In vitro system, RBP4 gene expression in visceral adipose tissue of normal weight normal glucose subjects was regulated by insulin,dexamethasone, pioglitazone, palmitic acid and TNF-α, such factors were also participated in the pathophysiological process of insulin resistance and type 2 diabetes.%目的 研究肥胖及2型糖尿病患者皮下和腹内脂肪组织视黄醇结合蛋白4(RBP4)mRNA的表达差异,并探讨影响其表达调控的因素.方法 选取2007年1-6月因非代谢性疾病而接受腹部择期手术的正常体重正常糖调节、单纯肥胖、2型糖尿病患者各9例,取皮下和腹内脂肪组织,用RT-PCR法检测RBP4 mRNA的表达,并在体外对正常体重正常糖调节者腹内脂肪组织分别与一定浓度的胰岛素、地塞米松、棕榈酸、肿瘤坏死因子-α、吡咯列酮共培养,用RT-PCR法检测药物对腹内脂肪组织RBP4 mRNA表达的变化.结果 肥胖和2型糖尿病患者腹内脂肪RBP4 mRNA的表达均显著高于正常体重正常糖调节者(分别为2.10±1.84和1.54±0.46比0.75±0.28,P<0.01和P<0.05),并明显高于相应的皮下脂肪组织;3组人群间皮下脂肪组织RBP4 mRNA的表达差异无统计学意义(1.05±0.15比0.99±0.14比1.13±0.07,P>0.05);药物胰岛素、地塞米松、吡咯列酮、棕榈酸能显著上调RBP4 mRNA的表达,与对照组相比,分别上升了2.13、0.84、2.04、4.88倍;肿瘤坏死因子-α显著下调RBP4 mRNA的表达,较对照组下降了38%.结论 肥胖和2型糖尿病患者腹内脂肪组织RBP4 mRNA的表达显著上升,正常体重正常糖调节者腹内脂肪组织RBP4 mRNA的表达受胰岛素、地塞米松等多种参与糖脂代谢及胰岛素抵抗因素的调控.

  19. Evaluation of renal function with urinary retinol binding protein and N-acetyl-β-glucosaminidase in preterm neonate%尿视黄醇结合蛋白和N-乙酰-β葡萄糖苷酶对早产儿肾功能的评价意义

    Institute of Scientific and Technical Information of China (English)

    吴峤微; 唐震; 沈南平

    2011-01-01

    目的 分析尿视黄醇结合蛋白(RBP)、尿N-乙酰-β葡萄糖苷酶(NAG)对评价早产儿肾功能的临床意义.方法 受选新生儿89例,分为早产儿窒息组(18例)、早产儿非窒息组(25例)和足月儿对照组(46例).观察所选对象生后48h内晨尿的RBP和NAG水平,分别与尿肌酐(Cr)相比(以RBP/Cr和NAG/Cr表示);观察血肌酐和血尿素氮,以及非窒息早产儿在生后0~48h,~96h,~168h的RBP/Cr、NAG/Cr变化情况.结果 早产儿窒息组的尿RBP/Cr水平[(0.951±0.629)g/mol]高于非窒息组[(0.389±0.281)g/mol]和足月儿对照组[(0.119±0.081)g/mol],3组间比较差异有统计学意义(P0.05).3组间的血肌酐和尿素氮比较差异无统计学意义(P>0.05).早产儿非窒息组尿RBP/Cr与胎龄和日龄均无线性相关(P>0.05),而NAG/Cr与胎龄呈线性负相关(r=-0.625,P0.05).The levels of serum Cr and BUN were no significant difference in the three groups(P>0.05).The urinary RBP/Cr level had non-linear correlation with either postnatal or gestational age in no-asphyxial preterm group.While the urinary NAG/Cr levels negative correlated with the gestational age(r=-0.625,P<0.05).And the correlation between the urinary NAG/Cr and postnatal age was postive(P<0.05).Conclusion The determination of urinary NAG/Cr and RBP/Cr provides a sensitive and reliable method to evaluate the renal function of neonates,especially in preterm infants.The RBP/Cr is affected by asphyxia more than NAG/Cr,which is rather correlated with gestational age.

  20. The Roles of Serum Visfatin and Retinol Binding Protein 4 in Patients with Type2 Diabetes Mellitus Complicated with Coronary Heart Disease%2型糖尿病合并冠心病患者血清内脂素和视黄醇结合蛋白4的临床意义

    Institute of Scientific and Technical Information of China (English)

    张高健; 邱蔚

    2013-01-01

    目的 探讨血清内脂素(visfatin)和视黄醇结合蛋白4(RBP4)水平与2 型糖尿病(T2DM)合并冠心病(CHD)的临床意义.方法 选取单纯T2DM(T2DM 组)患者61 例、T2DM 合并CHD(T2DM + CHD 组)患者58 例、单纯CHD(CHD 组)患者60 例、门诊健康体检者(对照组)60 例,检测各组血清内脂素、RBP4 水平、空腹血糖(FBG) 、总胆固醇(TC) 、三酰甘油(TG) 、低密度脂蛋白胆固醇(LDL-C) 、高密度脂蛋白胆固醇(HDL-C)水平,HbA1c 和空腹血清胰岛素(FINS),计算胰岛素抵抗指数(HOMA-IR) 、体重指数(BMI)及腰臀比(WHR),并作相关性分析.结果 T2DM + CHD 组血清内脂素和RBP4 水平均明显高于T2DM 组、CHD 组和对照组,差异均有统计学意义(q = 2.56 ~ 3.13,均P < 0.05).T2DM + CHD 组内脂素水平与WHR 、RBP4 、TG 和HOMA-IR 呈正相关( r = 0.27 ~ 0.52,均P < 0.05);T2DM 与RBP4 和HbA1c密切相关(OR= 2.09 ~ 3.67,P = 0.05),T2DM 合并CHD 与内脂素、RBP4 和TG 密切相关(OR = 2.13 ~ 3.81,P =0.05).结论 血清内脂素和RBP4 与T2DM 合并CHD 的发病有一定联系.

  1. Changes in Cellular mRNA Stability, Splicing, and Polyadenylation through HuR Protein Sequestration by a Cytoplasmic RNA Virus

    Directory of Open Access Journals (Sweden)

    Michael D. Barnhart

    2013-11-01

    Full Text Available The impact of RNA viruses on the posttranscriptional regulation of cellular gene expression is unclear. Sindbis virus causes a dramatic relocalization of the cellular HuR protein from the nucleus to the cytoplasm in infected cells. This is to the result of the expression of large amounts of viral RNAs that contain high-affinity HuR binding sites in their 3′ UTRs effectively serving as a sponge for the HuR protein. Sequestration of HuR by Sindbis virus is associated with destabilization of cellular mRNAs that normally bind HuR and rely on it to regulate their expression. Furthermore, significant changes can be observed in nuclear alternative polyadenylation and splicing events on cellular pre-mRNAs as a result of sequestration of HuR protein by the 3′ UTR of transcripts of this cytoplasmic RNA virus. These studies suggest a molecular mechanism of virus-host interaction that probably has a significant impact on virus replication, cytopathology, and pathogenesis.

  2. Protein tyrosine phosphatase is possibly involved in cellular signal transduction and the regulation of ABA accumulation in response to water deficit in Maize L. coleoptile

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Water deficit-induced ABA accumulation is an ideal model or "stimulus-response" system to investigate cellular stress signaling in plant cells, using such a model the cellular stress signaling triggered by water deficit was investigated in Maize L. coleoptile. Water deficit-induced ABA accumulation was sensitively blocked by NaVO3, a potent inhibitor both to plasma membrane H+-ATPase (PM-H+- ATPase) and protein tyrosine phosphatase (PTPase). However, while PM- H+-ATPase activity was unaffected under water deficit and PM- H+-ATPase activator did not induce an ABA accumulation instead of water deficit, water deficit induced an increase in the protein phosphatase activity, and furthermore, ABA accumulation was inhibited by PAO, a specific inhibitor of PTPase. These results indicate that protein phosphtases may be involved in the cellular signaling in response to water deficit. Further studies identified at least four species of protein phosphtase as assayed by using pNPP as substrate, among which one component was especially sensitive to NaVO3. The NaVO3-sensitive enzyme was purified and finally showed a protein band about 66 kD on SDS/PAGE. The purified enzyme showed a great activity to some specific PTPase substrates at pH 6.0. In addition to NaVO3, the enzyme was also sensitive to some other PTPase inhibitors such as Zn2+ and MO33+, but not to Ca2+ and Mg2+, indicating that it might be a protein tyrosine phosphatase. Interestingly, the purified enzyme could be deactivated by some reducing agent DTT, which was previously proved to be an inhibitor of water deficit-induced ABA accumulation. This result further proved that PTPase might be involved in the cellular signaling of ABA accumulation in response to water deficit.

  3. Changes in protein and nonprotein thiol contents in bladder, kidney and liver of mice by the pesticide sodium-o-phenylphenol and their possible role in cellular toxicity.

    Science.gov (United States)

    Narayan, S; Roy, D

    1992-02-01

    Acute treatment of mice with Na-o-phenylphenol or phenylbenzoquinone, an electrophilic metabolite of o-phenylphenol, resulted in differential depletion of contents of protein and nonprotein thiols in bladder, kidney and liver. Maximum decrease in the levels of protein and nonprotein reduced thiols was observed in bladder (by both agents) and was followed by kidney (by both agents) and liver (phenylbenzoquinone only). The reason for this differential changes in reduced thiol contents remains to be understood. The content of protein and nonprotein disulfides was higher in bladder of mice treated with Na-o-phenylphenol compared to that observed in untreated mice bladder. Phenyl 2,5'-p-benzoquinone mediated in vivo depletion of nonprotein and protein thiols suggests that Na-o-phenylphenol treatment may decrease in vivo thiols via the formation of phenylbenzoquinone. Increased disulfide formation is considered to represent an index of oxidative stress produced by chemical. Increases in the level of protein and nonprotein disulfides in bladder suggest as observed in this study that administration of Na-o-phenylphenol to mice produced oxidative stress in bladder. Products of redox cycling of xenobiotics are known to cause cellular toxicity via altering the homeostasis of thiol status. Therefore, it is concluded that decreases in protein thiol contents either via alkylation and/or oxidation of sulfhydryl groups of proteins and increases in disulfide contents presumably by products of redox cycling of Na-o-phenylphenol may play a role in Na-o-phenylphenol-induced cellular toxicity.

  4. Spindle assembly checkpoint protein expression correlates with cellular proliferation and shorter time to recurrence in ovarian cancer.

    LENUS (Irish Health Repository)

    McGrogan, Barbara

    2014-07-01

    Ovarian carcinoma (OC) is the most lethal of the gynecological malignancies, often presenting at an advanced stage. Treatment is hampered by high levels of drug resistance. The taxanes are microtubule stabilizing agents, used as first-line agents in the treatment of OC that exert their apoptotic effects through the spindle assembly checkpoint. BUB1-related protein kinase (BUBR1) and mitotic arrest deficient 2 (MAD2), essential spindle assembly checkpoint components, play a key role in response to taxanes. BUBR1, MAD2, and Ki-67 were assessed on an OC tissue microarray platform representing 72 OC tumors of varying histologic subtypes. Sixty-one of these patients received paclitaxel and platinum agents combined; 11 received platinum alone. Overall survival was available for all 72 patients, whereas recurrence-free survival (RFS) was available for 66 patients. Increased BUBR1 expression was seen in serous carcinomas, compared with other histologies (P = .03). Increased BUBR1 was significantly associated with tumors of advanced stage (P = .05). Increased MAD2 and BUBR1 expression also correlated with increased cellular proliferation (P < .0002 and P = .02, respectively). Reduced MAD2 nuclear intensity was associated with a shorter RFS (P = .03), in ovarian tumors of differing histologic subtype (n = 66). In this subgroup, for those women who received paclitaxel and platinum agents combined (n = 57), reduced MAD2 intensity also identified women with a shorter RFS (P < .007). For the entire cohort of patients, irrespective of histologic subtype or treatment, MAD2 nuclear intensity retained independent significance in a multivariate model, with tumors showing reduced nuclear MAD2 intensity identifying patients with a poorer RFS (P = .05).

  5. Proteomic screen in the simple metazoan Hydra identifies 14-3-3 binding proteins implicated in cellular metabolism, cytoskeletal organisation and Ca2+ signalling

    Directory of Open Access Journals (Sweden)

    Imhof Axel

    2007-07-01

    Full Text Available Abstract Background 14-3-3 proteins have been implicated in many signalling mechanisms due to their interaction with Ser/Thr phosphorylated target proteins. They are evolutionarily well conserved in eukaryotic organisms from single celled protozoans and unicellular algae to plants and humans. A diverse array of target proteins has been found in higher plants and in human cell lines including proteins involved in cellular metabolism, apoptosis, cytoskeletal organisation, secretion and Ca2+ signalling. Results We found that the simple metazoan Hydra has four 14-3-3 isoforms. In order to investigate whether the diversity of 14-3-3 target proteins is also conserved over the whole animal kingdom we isolated 14-3-3 binding proteins from Hydra vulgaris using a 14-3-3-affinity column. We identified 23 proteins that covered most of the above-mentioned groups. We also isolated several novel 14-3-3 binding proteins and the Hydra specific secreted fascin-domain-containing protein PPOD. In addition, we demonstrated that one of the 14-3-3 isoforms, 14-3-3 HyA, interacts with one Hydra-Bcl-2 like protein in vitro. Conclusion Our results indicate that 14-3-3 proteins have been ubiquitous signalling components since the start of metazoan evolution. We also discuss the possibility that they are involved in the regulation of cell numbers in response to food supply in Hydra.

  6. The influence of surface charge on serum protein interaction and cellular uptake: studies with dendritic polyglycerols and dendritic polyglycerol-coated gold nanoparticles

    Science.gov (United States)

    Bewersdorff, Tony; Vonnemann, Jonathan; Kanik, Asiye; Haag, Rainer; Haase, Andrea

    2017-01-01

    Nanoparticles (NPs) have gained huge interest in the medical field, in particular for drug delivery purposes. However, binding of proteins often leads to fast NP uptake and rapid clearance, thereby hampering medical applications. Thus, it is essential to determine and control the bio–nano interface. This study investigated the serum protein interactions of dendritic polyglycerols (dPGs), which are promising drug delivery candidates by means of two dimensional gel electrophoresis (2DE) in combination with mass spectrometry. In order to investigate the influence of surface charge, sulfated (sulfated dendritic polyglycerol [dPGS]) and non-sulfated (dPGOH) surfaces were applied, which were synthesized on a gold core allowing for easier separation from unbound biomolecules through centrifugation. Furthermore, two different sizes for dPGS were included. Although size had only a minor influence, considerable differences were detected in protein affinity for dPGS versus dPGOH surfaces, with dPGOH binding much less proteins. Cellular uptake into human CD14+ monocytes was analyzed by flow cytometry, and dPGOH was taken up to a much lower extent compared to dPGS. By using a pull-down approach, possible cellular interaction partners of serum pre-incubated dPGS-Au20 NPs from the membrane fraction of THP-1 cells could be identified such as for instance the transferrin receptor or an integrin. Clathrin-mediated endocytosis was further investigated using chlorpromazine as an inhibitor, which resulted in a 50% decrease of the cellular uptake of dPGS. This study could confirm the influence of surface charge on protein interactions and cellular uptake of dPGS. Furthermore, the approach allowed for the identification of possible uptake receptors and insights into the uptake mechanism. PMID:28352171

  7. Treponema pallidum subsp. pallidum TP0136 protein is heterogeneous among isolates and binds cellular and plasma fibronectin via its NH2-terminal end.

    Science.gov (United States)

    Ke, Wujian; Molini, Barbara J; Lukehart, Sheila A; Giacani, Lorenzo

    2015-03-01

    Adherence-mediated colonization plays an important role in pathogenesis of microbial infections, particularly those caused by extracellular pathogens responsible for systemic diseases, such as Treponema pallidum subsp. pallidum (T. pallidum), the agent of syphilis. Among T. pallidum adhesins, TP0136 is known to bind fibronectin (Fn), an important constituent of the host extracellular matrix. To deepen our understanding of the TP0136-Fn interaction dynamics, we used two naturally-occurring sequence variants of the TP0136 protein to investigate which region of the protein is responsible for Fn binding, and whether TP0136 would adhere to human cellular Fn in addition to plasma Fn and super Fn as previously reported. Fn binding assays were performed with recombinant proteins representing the two full-length TP0136 variants and their discrete regions. As a complementary approach, we tested inhibition of T. pallidum binding to Fn by recombinant full-length TP0136 proteins and fragments, as well as by anti-TP0136 immune sera. Our results show that TP0136 adheres more efficiently to cellular Fn than to plasma Fn, that the TP0136 NH2-terminal conserved region of the protein is primarily responsible for binding to plasma Fn but that binding sites for cellular Fn are also present in the protein's central and COOH-terminal regions. Additionally, message quantification studies show that tp0136 is highly transcribed during experimental infection, and that its message level increases in parallel to the host immune pressure on the pathogen, which suggests a possible role for this protein in T. pallidum persistence. In a time where syphilis incidence is high, our data will help in the quest to identify suitable targets for development of a much needed vaccine against this important disease.

  8. A novel antilithiatic protein from Tribulus terrestris having cytoprotective potency.

    Science.gov (United States)

    Aggarwal, Anshu; Tandon, Simran; Singla, Surinder Kumar; Tandon, Chanderdeep

    2012-08-01

    Adhesion of calcium oxalate (CaOx) crystals to kidney cells is a key event in kidney stones associated with marked hyperoxaluria. As the propensity of stone recurrence and persistent side effects are not altered by surgical techniques available, phytotherapeutic agents could be useful as an adjuvant therapy. The present study is aimed at examining the antilithiatic potency of the protein biomolecules of Tribulus terrestris, a plant which is a common constituent of herbal marketed preparations to treat urolithiasis. Various biochemical methods with mass spectrometry were used to purify and characterize the purified protein. The protective potency of the protein was tested on the oxalate induced injury on renal epithelial cell lines (NRK 52E). An antilithiatic protein having molecular weight of ~ 60kDa was purified. This purified protein showed similarities with Carotenoid cleavage dioxygenase 7 (CCD7) of Arabidopsis thaliana after matching peptide mass fingerprints in MASCOT search engine. An EF hand domain was identified in CCD7 by SCAN PROSITE. Presence of an EF hand domain, a characteristic feature of calcium binding proteins and a role in the synthesis of retinol which is transported by retinol binding protein, a protein found in kidney stone matrix; of CCD7 support the role of TTP as an antilithiatic protein. The protective potency of TTP on NRK 52E was quite comparable to the aqueous extract of cystone. Our findings suggest that this purified protein biomolecule from Tribulus terrestris could open new vista in medical management of urolithiasis.

  9. Cleavage of the HPV16 Minor Capsid Protei