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Sample records for hif-1alpha protein expression

  1. Cytoplasmic polyadenylation-element-binding protein (CPEB)1 and 2 bind to the HIF-1alpha mRNA 3'-UTR and modulate HIF-1alpha protein expression.

    Science.gov (United States)

    Hägele, Sonja; Kühn, Uwe; Böning, Melanie; Katschinski, Dörthe M

    2009-01-01

    The heterodimeric HIF (hypoxia-inducible factor)-1 is a transcriptional master regulator of several genes involved in mammalian oxygen homoeostasis. Besides the well described regulation of the HIF-1alpha subunit via hydroxylation-mediated protein stability in hypoxia, there are several indications of an additional translational control of the HIF-1alpha mRNA, especially after growth factor stimulation. We identified an interaction of CPEB (cytoplasmic polyadenylation-element-binding protein) 1 and CPEB2 with the 3'-UTR (untranslated region) of HIF-1alpha mRNA. Overexpression of CPEB1 and CPEB2 affected HIF-1alpha protein levels mediated by the 3'-UTR of HIF-1alpha mRNA. Stimulation of neuroblastoma SK-N-MC cells with insulin and thus activation of endogenous CPEBs increased the expression of a luciferase reporter gene fused to the 3'-UTR of HIF-1alpha as well as endogenous HIF-1alpha protein levels. This could be abrogated by treating the cells with CPEB1 or CPEB2 siRNAs (short interfering RNAs). Injection of HIF-1alpha cRNA into Xenopus oocytes verified the elongation of the poly(A)+ (polyadenylated) tail by cytoplasmic polyadenylation. Thus CPEB1 and CPEB2 are involved in the regulation of HIF-1alpha following insulin stimulation.

  2. Grape seed extract inhibits VEGF expression via reducing HIF-1alpha protein expression.

    Science.gov (United States)

    Lu, Jianming; Zhang, Keqiang; Chen, Shiuan; Wen, Wei

    2009-04-01

    Grape seed extract (GSE) is a widely consumed dietary supplement that has antitumor activity. Here, we have investigated the inhibitory effect of GSE on the expression of vascular endothelial growth factor (VEGF) and the mechanism underlying this action. We found that GSE inhibited VEGF messenger RNA (mRNA) and protein expression in U251 human glioma cells and MDA-MB-231 human breast cancer cells. GSE inhibited transcriptional activation of the VEGF gene through reducing protein but not mRNA expression of hypoxia-inducible factor (HIF) 1alpha. The inhibitory effect of GSE on HIF-1alpha expression was mainly through inhibiting HIF-1alpha protein synthesis rather than promoting protein degradation. Consistent with this result, GSE-suppressed phosphorylation of several important components involved in HIF-1alpha protein synthesis, such as Akt, S6 kinase and S6 protein. Furthermore, in the MDA-MB-231 tumor, we found that GSE treatment inhibited the expression of VEGF and HIF-1alpha and the phosphorylation of S6 kinase without altering the subcellular localization of HIF-1alpha, correlating with reduced vessel density and tumor size. Depletion of polyphenol with polyvinylpyrrolidone abolished the inhibitory activity of GSE, suggesting a water-soluble fraction of polyphenol in GSE is responsible for the inhibitory activity. Taken together, our results indicate that GSE inhibits VEGF expression by reducing HIF-1alpha protein synthesis through blocking Akt activation. This finding provides new insight into the mechanisms of anticancer activity of GSE and reveals a novel molecular mechanism underlying the antiangiogenic action of GSE.

  3. P70S6K 1 regulation of angiogenesis through VEGF and HIF-1{alpha} expression

    Energy Technology Data Exchange (ETDEWEB)

    Bian, Chuan-Xiu; Shi, Zhumei [Department of Pathology, Cancer Center, Nanjing Medical University, Nanjing 210029 (China); Meng, Qiao; Jiang, Yue; Liu, Ling-Zhi [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Jiang, Bing-Hua, E-mail: binghjiang@yahoo.com [Department of Pathology, Cancer Center, Nanjing Medical University, Nanjing 210029 (China); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States)

    2010-07-30

    Research highlights: {yields} P70S6K1 regulates VEGF expression; {yields} P70S6K1 induces transcriptional activation through HIF-1{alpha} binding site; {yields} P70S6K1 regulates HIF-1{alpha}, but not HIF-1{beta} protein expression; {yields} P70S6K1 mediates tumor growth and angiogenesis through HIF-1{alpha} and VEGF expression. -- Abstract: The 70 kDa ribosomal S6 kinase 1 (p70S6K1), a downstream target of phosphoinositide 3-kinase (PI3K) and ERK mitogen-activated protein kinase (MAPK), is an important regulator of cell cycle progression, and cell proliferation. Recent studies indicated an important role of p70S6K1 in PTEN-negative and AKT-overexpressing tumors. However, the mechanism of p70S6K1 in tumor angiogenesis remains to be elucidated. In this study, we specifically inhibited p70S6K1 activity in ovarian cancer cells using vector-based small interfering RNA (siRNA) against p70S6K1. We found that knockdown of p70S6K1 significantly decreased VEGF protein expression and VEGF transcriptional activation through the HIF-1{alpha} binding site at its enhancer region. The expression of p70S6K1 siRNA specifically inhibited HIF-1{alpha}, but not HIF-1{beta} protein expression. We also found that p70S6K1 down-regulation inhibited ovarian tumor growth and angiogenesis, and decreased cell proliferation and levels of VEGF and HIF-1{alpha} expression in tumor tissues. Our results suggest that p70S6K1 is required for tumor growth and angiogenesis through HIF-1{alpha} and VEGF expression, providing a molecular mechanism of human ovarian cancer mediated by p70S6K1 signaling.

  4. Estrogen Receptor beta 2 Induces Hypoxia Signature of Gene Expression by Stabilizing HIF-1 alpha in Prostate Cancer

    OpenAIRE

    Prasenjit Dey; Velazquez-Villegas, Laura A.; Michelle Faria; Anthony Turner; Philp Jonsson; Paul Webb; Cecilia Williams; Jan-Åke Gustafsson; Ström, Anders M.

    2015-01-01

    The estrogen receptor (ER) beta variant ER beta 2 is expressed in aggressive castration-resistant prostate cancer and has been shown to correlate with decreased overall survival. Genome-wide expression analysis after ER beta 2 expression in prostate cancer cells revealed that hypoxia was an overrepresented theme. Here we show that ER beta 2 interacts with and stabilizes HIF-1 alpha protein in normoxia, thereby inducing a hypoxic gene expression signature. HIF-1 alpha is known to stimulate met...

  5. [Effect of dominant negative HIF-1alpha (dn HIF-1alpha) on biological characteristics of uterine cervix cancer cells].

    Science.gov (United States)

    Tang, Bin-Zhi; Zhao, Feng-Yan; Wei, Ting; Mu, De-Zhi; Mao, Meng; Fu, Qiang; Zhang, Lin; Qu, Yia

    2008-05-01

    To explore the effect of dominant negative HIF-1alpha (dn HIF-1alpha) on biological characteristics of uterine cervix cancer cell SiHa and elucidate the related mechanism. pcDNA3. 1-dn HIF-1alpha was transfected into SiHa cells. The expression of HIF-1alpha and VEGF protein were detected by immunocytochemical method and Western Blotting. The growth proliferation of cells was surveyed by the MTT assay and cell apoptosis was detected through TUNEL after treated with CoCl2, meanwhile the results were compared with the group transfected with mock plasmid and untransfected group. After successfully transfected with relevant plasmid, there's no obvious difference of expression of HIF-1alpha among dn HIF-1alpha group, pcDNA3. 1 group, and untransfected group, however the expression of VEGF of dn HIF-1alpha group was significantly lower than that of the others (P dn HIF-1alpha group was obviously lower than that of the other two (P dn HIF-1alpha group among these three (P < 0.05). Domain negative HIF-1alpha can inhibit the proliferation of uterine cervix cancer cell and accelerate its apoptosis under hypoxia induced by CoCl2, as well as decrease the expression of VEGF protein. The implications of all this were that the domain negative HIF-1alpha may play an important role in the therapy of uterine cervix cancer.

  6. Expression of HIF-1{alpha} in irradiated tissue is altered by topical negative-pressure therapy

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, A.; Stange, S.; Labanaris, A.; Horch, R.E. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Plastic and Hand Surgery; Dimmler, A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Pathology; Sauer, R.; Grabenbauer, G. [Erlangen-Nuernberg Univ. (Germany). Dept. of Radiation Oncology

    2007-03-15

    Background and Purpose: Despite the enormous therapeutic potential of modern radiotherapy, common side effects such as radiation-induced wound healing disorders remain a well-known clinical phenomenon. Topical negative pressure therapy (TNP) is a novel tool to alleviate intraoperative, percutaneous irradiation or brachytherapy. Since TNP has been shown to positively influence the perfusion of chronic, poorly vascularized wounds, the authors applied this therapeutic method to irradiated wounds and investigated the effect on tissue oxygenation in irradiated tissue in five patients. Material and Methods: With informed patients' consent, samples prior to and 4 and 8 days after continuous TNP with -125 mmHg were obtained during routine wound debridements. Granulation tissue was stained with hematoxylin-eosin, and additionally with CD31, HIF-1{alpha} (hypoxia-inducible factor-1{alpha}), and D2-40 to detect blood vessels, measure indirect signs of hypoxia, and lymph vessel distribution within the pre- and post-TNP samples. Results: In this first series of experiments, a positive influence of TNP onto tissue oxygenation in radiation-induced wounds could be demonstrated. TNP led to a significant decrease of 53% HIF-1{alpha}-positive cell nuclei. At the same time, a slight reduction of CD31-stained capillaries was seen in comparison to samples before TNP. Immunostaining with D2-40 revealed an increased number of lymphatic vessels with distended lumina and an alteration of the parallel orientation within the post-TNP samples. Conclusion: This study is, to the authors' knowledge, the first report on a novel previously not described histological marker to demonstrate the effects of TNP on HIF-1{alpha} expression as an indirect marker of tissue oxygenation in irradiated wounds, as demonstrated by a reduction of HIF-1{alpha} concentration after TNP. Since this observation may be of significant value to develop possible new strategies to treat radiation-induced tissue

  7. SU-C-303-02: Correlating Metabolic Response to Radiation Therapy with HIF-1alpha Expression

    Energy Technology Data Exchange (ETDEWEB)

    Campos, D [University of Wisconsin Madison, Madison, WI (United States); Peeters, W [Radboud University Medical Center, Nijmegen, GA (United States); Nickel, K [University of Wisconsin, Madison, WI (United States); Eliceiri, K; Kimple, R; Van Der Kogel, A; Kissick, M [University of Wisconsin, Madison, Wisconsin (United States)

    2015-06-15

    Purpose: To understand radiation induced alterations in cellular metabolism which could be used to assess treatment or normal tissue response to aid in patient-specific adaptive radiotherapy. This work aims to compare the metabolic response of two head and neck cell lines, one malignant (UM-SCC-22B) and one benign (Normal Oral Keratinocyte), to ionizing radiation. Responses are compared to alterations in HIF-1alpha expression. These dynamics can potentially serve as biomarkers in assessing treatment response allowing for patient-specific adaptive radiotherapy. Methods: Measurements of metabolism and HIF-1alpha expression were taken before and X minutes after a 10 Gy dose of radiation delivered via an orthovoltage x-ray source. In vitro changes in metabolic activity were measured via fluorescence lifetime imaging (FLIM) to assess the mean lifetime of NADH autofluorescence following a dose of 10 Gy. HIF-1alpha expression was measured via immunohistochemical staining of in vitro treated cells and expression was quantified using the FIJI software package. Results: FLIM demonstrated a decrease in the mean fluorescence lifetime of NADH by 100 ps following 10 Gy indicating a shift towards glycolytic pathways for malignant cells; whereas this benign cell line showed little change in metabolic signature. Immunohistochemical analysis showed significant changes in HIF-1alpha expression in response to 10 Gy of radiation that correlate to metabolic profiles. Conclusion: Radiation induces significant changes in metabolic activity and HIF-1alpha expression. These alterations occur on time scales approximating the duration of common radiation treatments (approximately tens of minutes). Further understanding these dynamics has important implications with regard to improvement of therapy and biomarkers of treatment response.

  8. Gefitinib circumvents hypoxia-induced drug resistance by the modulation of HIF-1alpha.

    Science.gov (United States)

    Rho, Jin Kyung; Choi, Yun Jung; Lee, Jin Kyung; Ryoo, Baek-Yeol; Na, Im Ii; Yang, Sung Hyun; Kim, Cheol Hyeon; Yoo, Young Do; Lee, Jae Cheol

    2009-03-01

    Hypoxia-inducible factor-1alpha (HIF-1alpha) is a transcriptional factor which is activated by hypoxia and associated with cell survival, proliferation and drug resistance. Recent studies have shown that the down-stream molecules of the epidermal growth factor receptor (EGFR) signal are involved in the hypoxia-dependent or -independent HIF-1alpha protein accumulation. Thus, we hypothesized that an EGFR-TK inhibitor, gefitinib, might circumvent the hypoxia-induced drug resistance via the regulation of HIF-1alpha expression. In our data, treatment of gefitinib suppressed induced HIF-1alpha by hypoxia. This action of gefitinib was caused by reduced protein stability without any change in the level of HIF-1alpha mRNA. The effect of gefitinib on down-regulation of HIF-1alpha was reversed by transfection of constitutively active form of Akt. The cellular response to gefitinib was similar in both normoxia and hypoxia condition. However, the response to conventional chemotherapeutic drugs decreased >50% under hypoxia condition and they did not change HIF-1alpha expression. In addition, the suppression of HIF-1alpha using siRNA overcame partially hypoxia-induced drug resistance. In conclusion, gefitinib was able to circumvent hypoxia-induced drug resistance suggesting that the effective suppression of HIF-1alpha by the inhibition of EGFR-Akt pathway may overcome the hypoxia-induced drug resistance.

  9. BOLD-MRI of breast invasive ductal carcinoma: correlation of R2* value and the expression of HIF-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Min; Guo, Xiaojuan; Wang, Shuangkun [Capital Medical University, Department of Radiology, Beijing Chao Yang Hospital, Beijing (China); Jin, Mulan; Wang, Ying [Capital Medical University Beijing, Department of Pathology, Beijing Chaoyang Hospital, Beijing (China); Li, Jie; Liu, Jun [Capital Medical University Beijing, Department of Breast Surgery, Beijing Chaoyang Hospital, Beijing (China)

    2013-12-15

    To explore the reliability and feasibility of blood oxygenation level-dependent-based functional magnetic resonance imaging (BOLD-fMRI) to depict hypoxia in breast invasive ductal carcinoma. A total of 103 women with 104 invasive ductal carcinomas (IDCs) underwent breast BOLD-fMRI at 3.0 T. Histological specimens were analysed for tumour size, grade, axillary lymph nodes and expression of oestrogen receptors, progesterone receptors, human epidermal growth factor receptor 2, p53, Ki-67 and hypoxia inducible factor 1{alpha} (HIF-1{alpha}). The distribution and reliability of R2* were analysed. Correlations of the R2* value with the prognostic factors and HIF-1{alpha} were respectively analysed. The R2* map of IDC demonstrated a relatively heterogeneous signal. The mean R2* value was (53.4 {+-} 18.2) Hz. The Shapiro-Wilk test (W = 0.971, P = 0.020) suggested that the sample did not follow a normal distribution. The inter-rater and intrarater correlation coefficient was 0.967 and 0.959, respectively. The R2* values of IDCs were significantly lower in patients without axillary lymph nodes metastasis. The R2* value had a weak correlation with Ki67 expression (r = 0.208, P = 0.038). The mean R2* value correlated moderately with the level of HIF-1{alpha} (r = 0.516, P = 0.000). BOLD-fMRI is a simple and non-invasive technique that yields hypoxia information on breast invasive ductal carcinomas. (orig.)

  10. Noscapine inhibits hypoxia-mediated HIF-1alpha expression andangiogenesis in vitro: a novel function for an old drug.

    Science.gov (United States)

    Newcomb, Elizabeth W; Lukyanov, Yevgeniy; Schnee, Tona; Ali, M Aktar; Lan, Li; Zagzag, David

    2006-05-01

    Overexpression of hypoxia-inducible factor-1 (HIF-1) is a common feature in solid malignancies related to oxygen deficiency. Since increased HIF-1 expression correlates with advanced disease stage, increased angiogenesis and poor prognosis, HIF-1 and its signaling pathway have become targets for cancer chemotherapy. In this study, we identified noscapine to be a novel small molecule inhibitor of the HIF-1 pathway based on its structure-function relation-ships with HIF-1 pathway inhibitors belonging to the benzylisoquinoline class of plant metabolites and/or to microtubule binding agents. We demonstrate that noscapine treatment of human glioma U87MG and T98G cell lines exposed to the hypoxic mimetic agent, CoCl2, inhibits hypoxia-mediated HIF-1alpha expression and transcriptional activity as measured by decreased secretion of VEGF, a HIF-1 target gene. Inhibition of hypoxia-mediated HIF-1alpha expression was due, in part, to its ability to inhibit accumulation of HIF-1alpha in the nucleus and target it for degradation via the proteasome. One mechanism of action of microtubule binding agents is their antiangiogenic activity associated with disruption of endothelial tubule formation. We show that noscapine has similar properties in vitro. Thus, noscapine may possess novel antiangiogenic activity associated with two broad mechanisms of action: first, by decreasing HIF-1alpha expression in hypoxic tumor cells, upregulation of target genes, such as VEGF, would be decreased concomitant with its associated angiogenic activity; second, by inhibiting endothelial cells from forming blood vessels in response to VEGF stimulation, it may limit the process of neo-vascularization, correlating with antitumor activity in vivo. For more than 75 years, noscapine has traditionally been used as an oral cough suppressant with no known toxic side effects in man. Thus, the studies reported here have found a novel function for an old drug. Given its low toxicity profile, its demonstrated

  11. NF-{kappa}B suppresses HIF-1{alpha} response by competing for P300 binding

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, Daniela B.S., E-mail: daniela_mendonca@dentistry.unc.edu [Universidade Catolica de Brasilia, Pos-Graduacao em Ciencias Genomicas e Biotecnologia, SGAN Quadra 916, Av. W5 Norte, 70790-160 Brasilia, DF (Brazil); Bone Biology and Implant Therapy Laboratory, Department of Prosthodontics, University of North Carolina at Chapel Hill, 330 Brauer Hall, CB 7450, Chapel Hill, NC 27599 (United States); Mendonca, Gustavo [Universidade Catolica de Brasilia, Pos-Graduacao em Ciencias Genomicas e Biotecnologia, SGAN Quadra 916, Av. W5 Norte, 70790-160 Brasilia, DF (Brazil); Bone Biology and Implant Therapy Laboratory, Department of Prosthodontics, University of North Carolina at Chapel Hill, 330 Brauer Hall, CB 7450, Chapel Hill, NC 27599 (United States); Aragao, Francisco J.L. [Universidade Catolica de Brasilia, Pos-Graduacao em Ciencias Genomicas e Biotecnologia, SGAN Quadra 916, Av. W5 Norte, 70790-160 Brasilia, DF (Brazil); Embrapa Recursos Geneticos e Biotecnologia, Laboratorio de Introducao e Expressao de Genes, PqEB W5 Norte, 70770-900 Brasilia, DF (Brazil); Cooper, Lyndon F., E-mail: lyndon_cooper@dentistry.unc.edu [Bone Biology and Implant Therapy Laboratory, Department of Prosthodontics, University of North Carolina at Chapel Hill, 330 Brauer Hall, CB 7450, Chapel Hill, NC 27599 (United States)

    2011-01-28

    Research highlights: {yields} p65 completely blocked HIF-1{alpha} activity at the HRE on different cell lines. {yields} p65 caused minor changes in HIF-1{alpha} and HIF-1{alpha} target genes mRNA expression. {yields} p65 reduced transcription of VEGF promoter. {yields} p65 competes with HIF-1{alpha} for p300. -- Abstract: Hypoxia has emerged as a key determinant of osteogenesis. HIF-1{alpha} is the transcription factor mediating hypoxia responses that include induction of VEGF and related bone induction. Inflammatory signals antagonize bone repair via the NF-{kappa}B pathway. The present investigation explored the functional relationship of hypoxia (HIF-1{alpha} function) and inflammatory signaling (NF-{kappa}B) in stem like and osteoprogenitor cell lines. The potential interaction between HIF-1{alpha} and NF-{kappa}B signaling was explored by co-transfection studies in hFOB with p65, HIF-1{alpha} and 9x-HRE-luc or HIF-1{alpha} target genes reporter plasmids. Nuclear cross-talk was directly tested using the mammalian Gal4/VP16 two-hybrid, and confirmed by co-immunoprecipitation/western blotting assays. The results show that inflammatory stimulation (TNF-{alpha} treatment) causes a marked inhibition of HIF-1{alpha} function at the HRE in all cell lines studied. Also, co-transfection with p65 expression vector leads to reduced hVEGFp transcription after DFO-induced hypoxia. However, TNF-{alpha} treatment had little effect on HIF-1{alpha} mRNA levels. The functional interaction of Gal4-HIF-1{alpha} and VP16-p300 fusion proteins is effectively blocked by expression of p65 in a dose dependent manner. It was concluded that NF-{kappa}B-mediated inflammatory signaling is able to block HIF-1{alpha} transactivation at HRE-encoding genes by direct competition for p300 binding at the promoter. Inflammation may influence the stem cell niche and tissue regeneration by influencing cellular responses to hypoxia.

  12. Expression and regulation of HIF-1 alpha in macrophages under inflammatory conditions; significant reduction of VEGF by CaMKII inhibitor

    NARCIS (Netherlands)

    Westra, Johanna; Brouwer, Elisabeth; van Roosmalen, Ingrid A. M.; Doornbos-van der Meer, Berber; van Leeuwen, Miek A.; Posthumus, Marcel D.; Kallenberg, Cees G. M.; WESTRA, H

    2010-01-01

    Background: Macrophages expressing the pro-angiogenic transcription factor hypoxia-inducible factor (HIF)-1alpha have been demonstrated in rheumatoid arthritis (RA) in the synovial tissue. Aim of the present study was to investigate intracellular signal transduction regulation of pro-inflammatory HI

  13. Resistance to arginine deiminase treatment in melanoma cells is associated with induced argininosuccinate synthetase expression involving c-Myc/HIF-1alpha/Sp4.

    Science.gov (United States)

    Tsai, Wen-Bin; Aiba, Isamu; Lee, Soo-yong; Feun, Lynn; Savaraj, Niramol; Kuo, Macus Tien

    2009-12-01

    Arginine deiminase (ADI)-based arginine depletion is a novel strategy under clinical trials for the treatment of malignant melanoma with promising results. The sensitivity of melanoma to ADI treatment is based on its auxotrophy for arginine due to a lack of argininosuccinate synthetase (AS) expression, the rate-limiting enzyme for the de novo biosynthesis of arginine. We show here that AS expression can be transcriptionally induced by ADI in melanoma cell lines A2058 and SK-MEL-2 but not in A375 cells, and this inducibility was correlated with resistance to ADI treatment. The proximal region of the AS promoter contains an E-box that is recognized by c-Myc and HIF-1alpha and a GC-box by Sp4. Through ChIP assays, we showed that under noninduced conditions, the E-box was bound by HIF-1alpha in all the three melanoma cell lines. Under arginine depletion conditions, HIF-1alpha was replaced by c-Myc in A2058 and SK-MEL-2 cells but not in A375 cells. Sp4 was constitutively bound to the GC-box regardless of arginine availability in all three cell lines. Overexpressing c-Myc by transfection upregulated AS expression in A2058 and SK-MEL-2 cells, whereas cotransfection with HIF-1alpha suppressed c-Myc-induced AS expression. These results suggest that regulation of AS expression involves interplay among positive transcriptional regulators c-Myc and Sp4, and negative regulator HIF-1alpha that confers resistance to ADI treatment in A2058 and SK-MEL-2 cells. Inability of AS induction in A375 cells under arginine depletion conditions was correlated by the failure of c-Myc to interact with the AS promoter.

  14. MDM2 and HIF1alpha expression levels in different histologic subtypes of malignant pleural mesothelioma: correlation with pathological and clinical data

    Science.gov (United States)

    Mencoboni, Manlio; Grosso, Federica; Ceresoli, Giovanni Luca; Lunardi, Francesca; Vuljan, Stefania Edith; Bertorelle, Roberta; Sacchetto, Valeria; Ciminale, Vincenzo; Rea, Federico; Favaretto, Adolfo; Conte, PierFranco; Calabrese, Fiorella

    2015-01-01

    Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis and limited treatment options. Sarcomatoid/biphasic mesotheliomas are characterized by more aggressive behaviour and a poorer prognosis compared with the epithelioid subtype. To date prognostic and tailored therapeutic biomarkers are lacking. The present study analyzed the expression levels of MDM2 and HIF1alpha in different histologic subtypes from chemonaive MPM patients. Diagnostic biopsies of MPM patients from four Italian cancer centers were centrally collected and analyzed. MDM2 and HIF1alpha expression levels were investigated through immunohistochemistry and RT-qPCR. Pathological assessment of necrosis, inflammation and proliferation index was also performed. Molecular markers, pathological features and clinical characteristics were correlated to overall survival (OS) and progression free survival (PFS). Sixty MPM patients were included in the study (32 epithelioid and 28 non-epithelioid). Higher levels of MDM2 (p < 0.001), HIF1alpha (p = 0.013), necrosis (p = 0.013) and proliferation index (p < 0.001) were seen mainly in sarcomatoid/biphasic subtypes. Higher levels of inflammation were significantly associated with epithelioid subtype (p = 0.044). MDM2 expression levels were correlated with HIF1alpha levels (p = 0.0001), necrosis (p = 0.008) and proliferation index (p = 0.009). Univariate analysis showed a significant correlation of non-epithelioid histology (p = 0.04), high levels of necrosis (p = 0.037) and proliferation index (p = 0.0002) with shorter PFS. Sarcomatoid/biphasic and epithelioid mesotheliomas showed different MDM2 and HIF1alpha expression levels and were characterized by different levels of necrosis, proliferation and inflammation. Further studies are warranted to confirm a prognostic and predictive role of such markers and features. PMID:26544728

  15. HIF1-Alpha Expression Predicts Survival of Patients with Squamous Cell Carcinoma of the Oral Cavity

    Science.gov (United States)

    dos Santos, Marcelo; Mercante, Ana Maria da Cunha; Louro, Iúri Drumond; Gonçalves, Antônio José; de Carvalho, Marcos Brasilino; da Silva, Eloiza Helena Tajara; da Silva, Adriana Madeira Álvares

    2012-01-01

    Background Oral squamous cell carcinoma is an important cause of death and morbidity wordwide and effective prognostic markers are still to be discovered. HIF1α protein is associated with hypoxia response and neovascularization, essential conditions for solid tumors survival. The relationship between HIF1α expression, tumor progression and treatment response in head and neck cancer is still poorly understood. Patients and Methods In this study, we investigated HIF1α expression by immunohistochemistry in tissue microarrays and its relationship with clinical findings, histopathological results and survival of 66 patients with squamous cell carcinoma of the lower mouth. Results Our results demonstrated that high HIF1α expression is associated with local disease-free survival, independently from the choice of treatment. Furthermore, high expression of HIF1α in patients treated with postoperative radiotherapy was associated with survival, therefore being a novel prognostic marker in squamous cell carcinoma of the mouth. Additionally, our results showed that MVD was associated with HIF1α expression and local disease relapse. Conclusion These findings suggest that HIF1α expression can be used as a prognostic marker and predictor of postoperative radiotherapy response, helping the oncologist choose the best treatment for each patient. PMID:23028863

  16. MDM2 and HIF1alpha expression levels in different histologic subtypes of malignant pleural mesothelioma: correlation with pathological and clinical data.

    Science.gov (United States)

    Pasello, Giulia; Urso, Loredana; Mencoboni, Manlio; Grosso, Federica; Ceresoli, Giovanni Luca; Lunardi, Francesca; Vuljan, Stefania Edith; Bertorelle, Roberta; Sacchetto, Valeria; Ciminale, Vincenzo; Rea, Federico; Favaretto, Adolfo; Conte, PierFranco; Calabrese, Fiorella

    2015-12-08

    Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis and limited treatment options. Sarcomatoid/biphasic mesotheliomas are characterized by more aggressive behaviour and a poorer prognosis compared with the epithelioid subtype. To date prognostic and tailored therapeutic biomarkers are lacking. The present study analyzed the expression levels of MDM2 and HIF1alpha in different histologic subtypes from chemonaive MPM patients. Diagnostic biopsies of MPM patients from four Italian cancer centers were centrally collected and analyzed. MDM2 and HIF1alpha expression levels were investigated through immunohistochemistry and RT-qPCR. Pathological assessment of necrosis, inflammation and proliferation index was also performed. Molecular markers, pathological features and clinical characteristics were correlated to overall survival (OS) and progression free survival (PFS). Sixty MPM patients were included in the study (32 epithelioid and 28 non-epithelioid). Higher levels of MDM2 (p sarcomatoid/biphasic subtypes. Higher levels of inflammation were significantly associated with epithelioid subtype (p = 0.044). MDM2 expression levels were correlated with HIF1alpha levels (p = 0.0001), necrosis (p = 0.008) and proliferation index (p = 0.009). Univariate analysis showed a significant correlation of non-epithelioid histology (p = 0.04), high levels of necrosis (p = 0.037) and proliferation index (p = 0.0002) with shorter PFS. Sarcomatoid/biphasic and epithelioid mesotheliomas showed different MDM2 and HIF1alpha expression levels and were characterized by different levels of necrosis, proliferation and inflammation. Further studies are warranted to confirm a prognostic and predictive role of such markers and features.

  17. [Effect of HIF-1alpha on sex hormone levels and germ cell apoptosis of mice].

    Science.gov (United States)

    Chen, Xiang-Mei; Xiong, Yan-Lei; Gong, Hui; Xu, Cheng-Li

    2013-07-01

    To study the effect of hypoxia on hypothalamus-adenohypophysis-testis axis hormone levels, germ cell apoptosis and hypoxia-inducible factor-1alpha (HIF-1alpha) expression in testis of adolescent mice, and explore HIF-1alpha regulation on the reproductive function of male mice. Eighty SPF grade adolescent C57BL/6 mice were randomly divided into normoxia group, hypoxia 3, 7, 14 and 28 d groups. The level of serum testosterone (T), free testosterone (FT), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was analyzed by ELISA. Detected the sperm count, motility rate and abnormal sperm rate of epididymal sperm suspension. The apoptosis cells in testis were determined using TUNEL method. The expression of HIF-1alpha was analyzed using Western blot. Compared with corresponding normoxia group, serum T, FT, FSH and LH concentrations in hypoxia 3 d group were significantly higher (P apoptosis index (AI) of germ cells in hypoxia 7, 14 and 28 d groups significantly increased (P levels of HIF-1alpha protein expression were significantly higher (P HIF-1alpha protein highly expressed in mice testis could induce germ cell apoptosis increased in chronic hypoxia environment.

  18. Accumulation of Krebs cycle intermediates and over-expression of HIF1alpha in tumours which result from germline FH and SDH mutations.

    Science.gov (United States)

    Pollard, P J; Brière, J J; Alam, N A; Barwell, J; Barclay, E; Wortham, N C; Hunt, T; Mitchell, M; Olpin, S; Moat, S J; Hargreaves, I P; Heales, S J; Chung, Y L; Griffiths, J R; Dalgleish, A; McGrath, J A; Gleeson, M J; Hodgson, S V; Poulsom, R; Rustin, P; Tomlinson, I P M

    2005-08-01

    The nuclear-encoded Krebs cycle enzymes, fumarate hydratase (FH) and succinate dehydrogenase (SDHB, -C and -D), act as tumour suppressors. Germline mutations in FH predispose individuals to leiomyomas and renal cell cancer (HLRCC), whereas mutations in SDH cause paragangliomas and phaeochromocytomas (HPGL). In this study, we have shown that FH-deficient cells and tumours accumulate fumarate and, to a lesser extent, succinate. SDH-deficient tumours principally accumulate succinate. In situ analyses showed that these tumours also have over-expression of hypoxia-inducible factor 1alpha (HIF1alpha), activation of HIF1alphatargets (such as vascular endothelial growth factor) and high microvessel density. We found no evidence of increased reactive oxygen species in our cells. Our data provide in vivo evidence to support the hypothesis that increased succinate and/or fumarate causes stabilization of HIF1alpha a plausible mechanism, inhibition of HIF prolyl hydroxylases, has previously been suggested by in vitro studies. The basic mechanism of tumorigenesis in HPGL and HLRCC is likely to be pseudo-hypoxic drive, just as it is in von Hippel-Lindau syndrome.

  19. Persistent HIF-1alpha activation in gut ischemia/reperfusion injury: potential role of bacteria and lipopolysaccharide.

    Science.gov (United States)

    Koury, Jadd; Deitch, Edwin A; Homma, Hiroshi; Abungu, Billy; Gangurde, Pranoti; Condon, Michael R; Lu, Qi; Xu, Da-Zhong; Feinman, Rena

    2004-09-01

    In both animal models of hemorrhagic shock and clinical settings, shock-induced gut ischemia has been implicated in the development of the systemic inflammatory response syndrome and distant organ injury, yet the factors transducing these events remain to be fully determined. Because hypoxia-inducible factor (HIF-1), a transcription factor composed of oxygen-labile HIF-1alpha and constitutive HIF-1beta subunits, regulates the physiologic/pathophysiologic response to hypoxia and ischemia, we examined the HIF-1 response in two rat models of gut ischemia-reperfusion. We found that ileal nuclear HIF-1alpha protein levels were induced in rats subjected to trauma (laparotomy) plus hemorrhagic shock for 90 min relative to their trauma sham-shock and naïve counterparts and that this trauma hemorrhagic shock-induced mucosal HIF-1alpha protein response persisted after 1 h and 3 h of reperfusion. Likewise, in a model of isolated gut ischemia-reperfusion injury, where the superior mesenteric artery was occluded for 45 min, nuclear HIF-1alpha were induced in the gut mucosa relative to their sham counterparts and persisted after 1 h and 3 h or reperfusion. Similar to the in vivo response, in vitro hypoxia induced HIF-alpha expression in three different enterocyte cell lines (rat IEC-6 and human Caco-2 and HT-29 cell lines). However, in contrast to the in vivo response, HIF-1 expression rapidly disappeared on subsequent reoxygenation. Because in vivo enterocytes are exposed to bacteria, we tested whether the in vitro HIF-1alpha response would persist on reoxygenation if the enterocytes were cocultured with bacteria. P. aeruginosa, an enteric bacterium, markedly induced enterocyte HIF-1alpha protein levels under normoxic conditions. Furthermore, the addition of P. aeruginosa during either the hypoxic or reoxygenation phase prevented the degradation of HIF-1alpha protein levels. Moreover, the observation that lipopolysaccharide induced HIF-1alpha expression in a time

  20. 15-Deoxy-Delta(12,14)-prostaglandin-J(2) reveals a new pVHL-independent, lysosomal-dependent mechanism of HIF-1alpha degradation.

    Science.gov (United States)

    Olmos, Gemma; Arenas, María I; Bienes, Raquel; Calzada, María Jose; Aragonés, Julián; Garcia-Bermejo, Maria Laura; Landazuri, Manuel O; Lucio-Cazaña, Javier

    2009-07-01

    Hypoxia-inducible factor-1alpha (HIF-1alpha) protein is degraded under normoxia by its association to von Hippel-Lindau protein (pVHL) and further proteasomal digestion. However, human renal cells HK-2 treated with 15-deoxy-Delta(12,14)-prostaglandin-J(2) (15d-PGJ(2)) accumulate HIF-1alpha in normoxic conditions. Thus, we aimed to investigate the mechanism involved in this accumulation. We found that 15d-PGJ(2) induced an over-accumulation of HIF-1alpha in RCC4 cells, which lack pVHL and in HK-2 cells treated with inhibitors of the pVHL-proteasome pathway. These results indicated that pVHL-proteasome-independent mechanisms are involved, and therefore we aimed to ascertain them. We have identified a new lysosomal-dependent mechanism of HIF-1alpha degradation as a target for 15d-PGJ(2) based on: (1) HIF-1alpha colocalized with the specific lysosomal marker Lamp-2a, (2) 15d-PGJ(2) inhibited the activity of cathepsin B, a lysosomal protease, and (3) inhibition of lysosomal activity did not result in over-accumulation of HIF-1alpha in 15d-PGJ(2)-treated cells. Therefore, expression of HIF-1alpha is also modulated by lysosomal degradation.

  1. Hypoxia inducible factor-1-alpha (HIF-1 alpha) is related to both angiogenesis and inflammation in rheumatoid arthritis

    NARCIS (Netherlands)

    Brouwer, E.; Gouw, A. S. H.; Posthumus, M. D.; van Leeuwen, M. A.; Boerboom, A. L.; Bijzet, J.; Limburg, P. C.; Kallenberg, C. G. M.; Westra, J.; Bos, R

    2009-01-01

    Objectives Despite the important role of the transcription factor HIF-1 alpha in angiogenesis and inflammation, only a few studies on HIF-1 alpha expression have been performed in RA patients. The aim of the present study was to identify the layer in synovial tissue of RA patients where HIF1 alpha i

  2. The relationship between factor inhibiting HIF-1-alpha (HIF1AN( expression and vascular invasion in colon cancer

    Directory of Open Access Journals (Sweden)

    Reza Najafipour

    2016-10-01

    Full Text Available Background: Hypoxia is a common phenomenon in human solid tumors which by increasing in angiogenesis induction cause tumor growth survival and metastasis. Inhibitory factor hypoxia regulatory factor (HIF1AN by binding to transcription co activators CBP/P300(, inhibits hypoxia inducible factor (HIF1α. Objective: The relationship between HIF1AN expression and vascular invasion in colon tumors. Methods: The study included 101 patients with colon adenocarcinoma which were divided to vascular invasion and non-vascular invasion groups. Tumor paraffin blocks were immunohistochemistry stained for HIF1AN and were assessed for intensity and extent of positivity. Statistical relation of marker expression and clinic pathologic findings were assessed. Data were analyzed by SPSS 21 software and logistic regression and chi-square test. Findings: Nuclear immunoreactivity of HIF1AN was different between two groups. Statistical relation between low HIF1AN expression and tumor vascular invasion were seen (P=0.01. No relation was found between tumor differentiation, depth and HIF1AN. Conclusion: Evidence showed that the low expression or incorrect position of HIF1AN in nucleus of tumor cells was effective on HIF1α inhibition failure and factors associated angiogenesis increased. The HIF1AN played an tumor suppressor gene (TSG( role in colon tumors and decreased protein in the nucleus of colon cancer cells increased the expression of angiogenesis factors and vascular invasion.

  3. Cloning and characterization of the rat HIF-1 alpha prolyl-4-hydroxylase-1 gene.

    Science.gov (United States)

    Cobb, Ronald R; McClary, John; Manzana, Warren; Finster, Silke; Larsen, Brent; Blasko, Eric; Pearson, Jennifer; Biancalana, Sara; Kauser, Katalin; Bringmann, Peter; Light, David R; Schirm, Sabine

    2005-08-01

    Prolyl-4-hydroxylase domain-containing enzymes (PHDs) mediate the oxygen-dependent regulation of the heterodimeric transcription factor hypoxia-inducible factor-1 (HIF-1). Under normoxic conditions, one of the subunits of HIF-1, HIF-1alpha, is hydroxylated on specific proline residues to target HIF-1alpha for degradation by the ubiquitin-proteasome pathway. Under hypoxic conditions, the hydroxylation by the PHDs is attenuated by lack of the oxygen substrate, allowing HIF-1 to accumulate, translocate to the nucleus, and mediate HIF-mediated gene transcription. In several mammalian species including humans, three PHDs have been identified. We report here the cloning of a full-length rat cDNA that is highly homologous to the human and murine PHD-1 enzymes and encodes a protein that is 416 amino acids long. Both cDNA and protein are widely expressed in rat tissues and cell types. We demonstrate that purified and crude baculovirus-expressed rat PHD-1 exhibits HIF-1alpha specific prolyl hydroxylase activity with similar substrate affinities and is comparable to human PHD-1 protein.

  4. Real-time imaging of HIF-1alpha stabilization and degradation.

    Directory of Open Access Journals (Sweden)

    Ekaterina Moroz

    Full Text Available HIF-1alpha is overexpressed in many human cancers compared to normal tissues due to the interaction of a multiplicity of factors and pathways that reflect specific genetic alterations and extracellular stimuli. We developed two HIF-1alpha chimeric reporter systems, HIF-1alpha/FLuc and HIF-1alpha(DeltaODDD/FLuc, to investigate the tightly controlled level of HIF-1alpha protein in normal (NIH3T3 and HEK293 and glioma (U87 cells. These reporter systems provided an opportunity to investigate the degradation of HIF-1alpha in different cell lines, both in culture and in xenografts. Using immunofluorescence microscopy, we observed different patterns of subcellular localization of HIF-1alpha/FLuc fusion protein between normal cells and cancer cells; similar differences were observed for HIF-1alpha in non-transduced, wild-type cells. A dynamic cytoplasmic-nuclear exchange of the fusion protein and HIF-1alpha was observed in NIH3T3 and HEK293 cells under different conditions (normoxia, CoCl2 treatment and hypoxia. In contrast, U87 cells showed a more persistent nuclear localization pattern that was less affected by different growing conditions. Employing a kinetic model for protein degradation, we were able to distinguish two components of HIF-1alpha/FLuc protein degradation and quantify the half-life of HIF-1alpha fusion proteins. The rapid clearance component (t(1/2 approximately 4-6 min was abolished by the hypoxia-mimetic CoCl2 MG132 treatment and deletion of ODD domain, and reflects the oxygen/VHL-dependent degradation pathway. The slow clearance component (t(1/2 approximately 200 min is consistent with other unidentified non-oxygen/VHL-dependent degradation pathways. Overall, the continuous bioluminescence readout of HIF-1alpha/FLuc stabilization in vitro and in vivo will facilitate the development and validation of therapeutics that affect the stability and accumulation of HIF-1alpha.

  5. Castration Therapy of Prostate Cancer Results in Downregulation of HIF-1{alpha} Levels

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ubaidi, Firas L.T. [Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm (Sweden); Department of Urology, Central Hospital, Vaesteras (Sweden); Schultz, Niklas [Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm (Sweden); Egevad, Lars [Department of Oncology-Pathology, Karolinska Institutet, Stockholm (Sweden); Granfors, Torvald [Department of Urology, Central Hospital, Vaesteras (Sweden); Helleday, Thomas, E-mail: helleday@gmt.su.se [Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm (Sweden); Gray Institute for Radiation Oncology and Biology, University of Oxford, Oxford (United Kingdom); Science for Life Laboratory, Stockholm University, Solna (Sweden)

    2012-03-01

    Background and Purpose: Neoadjuvant androgen deprivation in combination with radiotherapy of prostate cancer is used to improve radioresponsiveness and local tumor control. Currently, the underlying mechanism is not well understood. Because hypoxia causes resistance to radiotherapy, we wanted to test whether castration affects the degree of hypoxia in prostate cancer. Methods and Materials: In 14 patients with locally advanced prostate cancer, six to 12 prostatic needle core biopsy specimens were taken prior to castration therapy. Bilateral orchidectomy was performed in 7 patients, and 7 were treated with a GnRH-agonist (leuprorelin). After castrationm two to four prostatic core biopsy specimens were taken, and the level of hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) in cancer was determined by immunofluorescence. Results: Among biopsy specimens taken before castration, strong HIF-1{alpha} expression (mean intensity above 30) was shown in 5 patients, weak expression (mean intensity 10-30) in 3 patients, and background levels of HIF-1{alpha} (mean intensity 0-10) in 6 patients. Downregulation of HIF-1{alpha} expression after castration was observed in all 5 patients with strong HIF-1{alpha} precastration expression. HIF-1{alpha} expression was also reduced in 2 of 3 patients with weak HIF-1{alpha} precastration expression. Conclusions: Our data suggest that neoadjuvant castration decreases tumor cell hypoxia in prostate cancer, which may explain increased radiosensitivity after castration.

  6. HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia.

    Directory of Open Access Journals (Sweden)

    Freya M Mowat

    Full Text Available BACKGROUND: Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF and erythropoietin (Epo by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO. CONCLUSIONS/SIGNIFICANCE: Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation

  7. TIAR and TIA-1 mRNA binding proteins co-aggregate under conditions of rapid oxygen decline and extreme hypoxia, suppress HIF-1alpha pathway and inhibit proliferation and angiogenesis

    OpenAIRE

    Gottschald, Oana Raluca

    2010-01-01

    T-cell intracellular antigen (TIA)-1 and TIA-1 related protein (TIAR) are mRNA-binding proteins that aggregate within stress granules under specific stress conditions. In this study, we analyzed TIAR/TIA-1 aggregation under different hypoxic conditions, and studied the effects on hypoxia-inducible factor (HIF)-1alpha, as well as on proliferation and angiogenesis. TIAR/TIA-1 formed stress granules under acute and pronounced hypoxic conditions in A549 adenocarcinoma cells. In parallel, HIF-1alp...

  8. Loss of skeletal muscle HIF-1alpha results in altered exercise endurance.

    Directory of Open Access Journals (Sweden)

    Steven D Mason

    2004-10-01

    Full Text Available The physiological flux of oxygen is extreme in exercising skeletal muscle. Hypoxia is thus a critical parameter in muscle function, influencing production of ATP, utilization of energy-producing substrates, and manufacture of exhaustion-inducing metabolites. Glycolysis is the central source of anaerobic energy in animals, and this metabolic pathway is regulated under low-oxygen conditions by the transcription factor hypoxia-inducible factor 1alpha (HIF-1alpha. To determine the role of HIF-1alpha in regulating skeletal muscle function, we tissue-specifically deleted the gene encoding the factor in skeletal muscle. Significant exercise-induced changes in expression of genes are decreased or absent in the skeletal-muscle HIF-1alpha knockout mice (HIF-1alpha KOs; changes in activities of glycolytic enzymes are seen as well. There is an increase in activity of rate-limiting enzymes of the mitochondria in the muscles of HIF-1alpha KOs, indicating that the citric acid cycle and increased fatty acid oxidation may be compensating for decreased flow through the glycolytic pathway. This is corroborated by a finding of no significant decreases in muscle ATP, but significantly decreased amounts of lactate in the serum of exercising HIF-1alpha KOs. This metabolic shift away from glycolysis and toward oxidation has the consequence of increasing exercise times in the HIF-1alpha KOs. However, repeated exercise trials give rise to extensive muscle damage in HIF-1alpha KOs, ultimately resulting in greatly reduced exercise times relative to wild-type animals. The muscle damage seen is similar to that detected in humans in diseases caused by deficiencies in skeletal muscle glycogenolysis and glycolysis. Thus, these results demonstrate an important role for the HIF-1 pathway in the metabolic control of muscle function.

  9. Extended ischemia prevents HIF1alpha degradation at reoxygenation by impairing prolyl-hydroxylation: role of Krebs cycle metabolites.

    Science.gov (United States)

    Serra-Pérez, Anna; Planas, Anna M; Núñez-O'Mara, Analía; Berra, Edurne; García-Villoria, Judit; Ribes, Antònia; Santalucía, Tomàs

    2010-06-11

    Hypoxia-inducible factor (HIF) is a heterodimeric transcription factor that activates the cellular response to hypoxia. The HIF1alpha subunit is constantly synthesized and degraded under normoxia, but degradation is rapidly inhibited when oxygen levels drop. Oxygen-dependent hydroxylation by prolyl-4-hydroxylases (PHD) mediates HIF1alpha proteasome degradation. Brain ischemia limits the availability not only of oxygen but also of glucose. We hypothesized that this circumstance could have a modulating effect on HIF. We assessed the separate involvement of oxygen and glucose in HIF1alpha regulation in differentiated neuroblastoma cells subjected to ischemia. We report higher transcriptional activity and HIF1alpha expression under oxygen deprivation in the presence of glucose (OD), than in its absence (oxygen and glucose deprivation, OGD). Unexpectedly, HIF1alpha was not degraded at reoxygenation after an episode of OGD. This was not due to impairment of proteasome function, but was associated with lower HIF1alpha hydroxylation. Krebs cycle metabolites fumarate and succinate are known inhibitors of PHD, while alpha-ketoglutarate is a co-substrate of the reaction. Lack of HIF1alpha degradation in the presence of oxygen was accompanied by a very low alpha-ketoglutarate/fumarate ratio. Furthermore, treatment with a fumarate analogue prevented HIF1alpha degradation under normoxia. In all, our data suggest that postischemic metabolic alterations in Krebs cycle metabolites impair HIF1alpha degradation in the presence of oxygen by decreasing its hydroxylation, and highlight the involvement of metabolic pathways in HIF1alpha regulation besides the well known effects of oxygen.

  10. NF-kappaB links innate immunity to the hypoxic response through transcriptional regulation of HIF-1alpha.

    Science.gov (United States)

    Rius, Jordi; Guma, Monica; Schachtrup, Christian; Akassoglou, Katerina; Zinkernagel, Annelies S; Nizet, Victor; Johnson, Randall S; Haddad, Gabriel G; Karin, Michael

    2008-06-05

    The hypoxic response is an ancient stress response triggered by low ambient oxygen (O2) (ref. 1) and controlled by hypoxia-inducible transcription factor-1 (HIF-1), whose alpha subunit is rapidly degraded under normoxia but stabilized when O2-dependent prolyl hydroxylases (PHDs) that target its O2-dependent degradation domain are inhibited. Thus, the amount of HIF-1alpha, which controls genes involved in energy metabolism and angiogenesis, is regulated post-translationally. Another ancient stress response is the innate immune response, regulated by several transcription factors, among which NF-kappaB plays a central role. NF-kappaB activation is controlled by IkappaB kinases (IKK), mainly IKK-beta, needed for phosphorylation-induced degradation of IkappaB inhibitors in response to infection and inflammation. IKK-beta is modestly activated in hypoxic cell cultures when PHDs that attenuate its activation are inhibited. However, defining the relationship between NF-kappaB and HIF-1alpha has proven elusive. Using in vitro systems, it was reported that HIF-1alpha activates NF-kappaB, that NF-kappaB controls HIF-1alpha transcription and that HIF-1alpha activation may be concurrent with inhibition of NF-kappaB. Here we show, with the use of mice lacking IKK-beta in different cell types, that NF-kappaB is a critical transcriptional activator of HIF-1alpha and that basal NF-kappaB activity is required for HIF-1alpha protein accumulation under hypoxia in cultured cells and in the liver and brain of hypoxic animals. IKK-beta deficiency results in defective induction of HIF-1alpha target genes including vascular endothelial growth factor. IKK-beta is also essential for HIF-1alpha accumulation in macrophages experiencing a bacterial infection. Hence, IKK-beta is an important physiological contributor to the hypoxic response, linking it to innate immunity and inflammation.

  11. Hypoxia in Tumor Angiogenesis and Metastasis: Evaluation of VEGF and MMP Over-expression and Down-Regulation of HIF-1alpha with RNAi in Hypoxic Tumor Cells

    Science.gov (United States)

    Shah, Shruti

    Background: As tumor mass grows beyond a few millimeters in diameter, the angiogenic "switch" is turned on leading to recruitment of blood vessels from surrounding artery and veins. However, the tumor mass is poorly perfused and there are pockets of hypoxia or lower oxygen concentrations relative to normal tissue. Hypoxia-inducing factor-1a (HIF-1a), a transcription factor, is activated when the oxygen concentration is low. Upon activation of HIF-1a, a number of other genes also turn on that allows the tumor to become more aggressive and resistant to therapy. Purpose: The main objectives of this study were to evaluate the effect of hypoxia-induced HIF-1a followed by over-expression of angiogenic and metastatic markers in tumor cells and down-regulation of HIF-1a using nanoparticle-delivered RNA interference therapy. Methods: Human ovarian (SKOV3) and breast (MDA-MB-231) adenocarcinoma cells were incubated under normoxic and hypoxic conditions. Following hypoxia treatment of the cells, HIF-1α, vascular endothelial growth factor (VEGF), matrix metalloproteinase 2 (MMP-2), and MMP-9 expression was analyzed qualitatively and quantitatively. For intracellular delivery of HIF-1a gene silencing small interfering RNA (siRNA), type B gelatin nanoparticles were fabricated using the solvent displacement method and the surface was modified with poly(ethylene glycol) (PEG, Mol. wt. 2kDa). Cellular uptake and distribution of the nanoparticles was observed with Cy3-siRNA loaded, FITC-conjugated gelatin nanoparticles. Cytotoxicity of the nanoparticle formulations was evaluated in both the cell lines. siRNA was transfected in the gelatin nanoparticles under hypoxic conditions. Total cellular protein and RNA were extracted for analysis of HIF1a, VEGF, MMP-2 and MMP-9 expression. Results: MDA-MB-231 and SKOV3 cells show increased expression of HIF1a under hypoxic conditions compared to baseline levels at normoxic conditions. ELISA and western blots of VEGF, MMP-2 and MMP-9 appear to

  12. Inhibition of protein kinase C delta attenuates allergic airway inflammation through suppression of PI3K/Akt/mTOR/HIF-1 alpha/VEGF pathway.

    Directory of Open Access Journals (Sweden)

    Yun Ho Choi

    Full Text Available Vascular endothelial growth factor (VEGF is supposed to contribute to the pathogenesis of allergic airway disease. VEGF expression is regulated by a variety of stimuli such as nitric oxide, growth factors, and hypoxia-inducible factor-1 alpha (HIF-1α. Recently, inhibition of the mammalian target of rapamycin (mTOR has been shown to alleviate cardinal asthmatic features, including airway hyperresponsiveness, eosinophilic inflammation, and increased vascular permeability in asthma models. Based on these observations, we have investigated whether mTOR is associated with HIF-1α-mediated VEGF expression in allergic asthma. In studies with the mTOR inhibitor rapamycin, we have elucidated the stimulatory role of a mTOR-HIF-1α-VEGF axis in allergic response. Next, the mechanisms by which mTOR is activated to modulate this response have been evaluated. mTOR is known to be regulated by phosphoinositide 3-kinase (PI3K/Akt or protein kinase C-delta (PKC δ in various cell types. Consistent with these, our results have revealed that suppression of PKC δ by rottlerin leads to the inhibition of PI3K/Akt activity and the subsequent blockade of a mTOR-HIF-1α-VEGF module, thereby attenuating typical asthmatic attack in a murine model. Thus, the present data indicate that PKC δ is necessary for the modulation of the PI3K/Akt/mTOR signaling cascade, resulting in a tight regulation of HIF-1α activity and VEGF expression. In conclusion, PKC δ may represent a valuable target for innovative therapeutic treatment of allergic airway disease.

  13. Regular endurance training reduces the exercise induced HIF-1alpha and HIF-2alpha mRNA expression in human skeletal muscle in normoxic conditions

    DEFF Research Database (Denmark)

    Lundby, Carsten; Gassmann, Max; Pilegaard, Henriette

    2005-01-01

    Regular exercise induces a variety of adaptive responses that enhance the oxidative and metabolic capacity of human skeletal muscle. Although the physiological adjustments of regular exercise have been known for decades, the underlying mechanisms are still unclear. The hypoxia inducible factors 1...... with a single exercise bout, and that this response is blunted with training. We obtained muscle biopsies from a trained (5 days/week during 4 weeks) and untrained leg from the same human subject before, immediately after, and during the recovery from a 3 h two-legged knee extensor exercise bout, where the two......alpha and HIF-2alpha mRNA levels are transiently increased in untrained human skeletal muscle in response to an acute exercise bout, but this response is blunted after exercise training. We propose that HIFs expression is upregulated with exercise and that it may be an important transcription factor...

  14. The G protein-coupled receptor 30 is up-regulated by hypoxia-inducible factor-1alpha (HIF-1alpha) in breast cancer cells and cardiomyocytes.

    Science.gov (United States)

    Recchia, Anna Grazia; De Francesco, Ernestina Marianna; Vivacqua, Adele; Sisci, Diego; Panno, Maria Luisa; Andò, Sebastiano; Maggiolini, Marcello

    2011-03-25

    GPR30, also known as GPER, has been suggested to mediate rapid effects induced by estrogens in diverse normal and cancer tissues. Hypoxia is a common feature of solid tumors involved in apoptosis, cell survival, and proliferation. The response to low oxygen environment is mainly mediated by the hypoxia-inducible factor named HIF-1α, which activates signaling pathways leading to adaptive mechanisms in tumor cells. Here, we demonstrate that the hypoxia induces HIF-1α expression, which in turn mediates the up-regulation of GPER and its downstream target CTGF in estrogen receptor-negative SkBr3 breast cancer cells and in HL-1 cardiomyocytes. Moreover, we show that HIF-1α-responsive elements located within the promoter region of GPER are involved in hypoxia-dependent transcription of GPER, which requires the ROS-induced activation of EGFR/ERK signaling in both SkBr3 and HL-1 and cells. Interestingly, the apoptotic response to hypoxia was prevented by estrogens through GPER in SkBr3 cells. Taken together, our data suggest that the hypoxia-induced expression of GPER may be included among the mechanisms involved in the anti-apoptotic effects elicited by estrogens, particularly in a low oxygen microenvironment.

  15. Granulocyte colony-stimulating factor activating HIF-1alpha acts synergistically with erythropoietin to promote tissue plasticity.

    Directory of Open Access Journals (Sweden)

    Shih-Ping Liu

    Full Text Available Stroke and peripheral limb ischemia are serious clinical problems with poor prognosis and limited treatment. The cytokines erythropoietin (EPO and granulocyte-colony stimulating factor (G-CSF have been used to induce endogenous cell repair and angiogenesis. Here, we demonstrated that the combination therapy of EPO and G-CSF exerted synergistic effects on cell survival and functional recovery from cerebral and peripheral limbs ischemia. We observed that even under normoxic conditions, G-CSF activates hypoxia-inducible factor-1alpha (HIF-1alpha, which then binds to the EPO promoter and enhances EPO expression. Serum EPO level was significantly increased by G-CSF injection, with the exception of Tg-HIF-1alpha(+f/+f mice. The neuroplastic mechanisms exerted by EPO combined with G-CSF included enhanced expression of the antiapoptotic protein of Bcl-2, augmented neurotrophic factors synthesis, and promoted neovascularization. Further, the combination therapy significantly increased homing and differentiation of bone marrow stem cells (BMSCs and intrinsic neural progenitor cells (INPCs into the ischemic area. In summary, EPO in combination with G-CSF synergistically enhanced angiogenesis and tissue plasticity in ischemic animal models, leading to greater functional recovery than either agent alone.

  16. Inhibition of HIF-1{alpha} activity by BP-1 ameliorates adjuvant induced arthritis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Shankar, J. [Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago (United States); Thippegowda, P.B., E-mail: btprabha@uic.edu [Department of Pharmacology, (M/C 868), College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave., Chicago, IL 60612 (United States); Kanum, S.A. [Department of Chemistry, Yuvaraj' s College, University of Mysore, Mysore (India)

    2009-09-18

    Rheumatoid arthritis (RA) is a chronic inflammatory, angiogenic disease. Inflamed synovitis is a hallmark of RA which is hypoxic in nature. Vascular endothelial growth factor (VEGF), one of the key regulators of angiogenesis, is overexpressed in the pathogenesis of RA. VEGF expression is regulated by hypoxia-inducible factor-1{alpha} (HIF-1{alpha}), a master regulator of homeostasis which plays a pivotal role in hypoxia-induced angiogenesis. In this study we show that synthetic benzophenone analogue, 2-benzoyl-phenoxy acetamide (BP-1) can act as a novel anti-arthritic agent in an experimental adjuvant induced arthritis (AIA) rat model by targeting VEGF and HIF-1{alpha}. BP-1 administered hypoxic endothelial cells and arthritic animals clearly showed down regulation of VEGF expression. Further, BP-1 inhibits nuclear translocation of HIF-1{alpha}, which in turn suppresses transcription of the VEGF gene. These results suggest a further possible clinical application of the BP-1 derivative as an anti-arthritic agent in association with conventional chemotherapeutic agents.

  17. Pilocarpine protects cobalt chloride-induced apoptosis of RGC-5 cells: involvement of muscarinic receptors and HIF-1 alpha pathway.

    Science.gov (United States)

    Zhu, Xu; Zhou, Wei; Cui, Yongyao; Zhu, Liang; Li, Juan; Feng, Xuemei; Shao, Biyun; Qi, Hong; Zheng, Jun; Wang, Hao; Chen, Hongzhuan

    2010-04-01

    The retina is the most metabolically active tissue in the human body and hypoxia-induced retinal ganglion cell (RGC) death has been implicated in glaucomatous optic neuropathy. The aim of this study is to determine whether muscarinic receptor agonist pilocarpine, a classic antiglaucoma drug, possesses neuroprotection against cobalt chloride (CoCl(2))-mimetic hypoxia-induced apoptosis of rat retinal ganglion cells (RGC-5 cells) and its underlying mechanisms. Cell viability was determined by Cell Counting Kit-8 assay and apoptosis was examined by annexin V and mitochondrial membrane potential (MMP) assays. Expressions of hypoxia-induced factor-1 alpha (HIF-1 alpha), p53, and BNIP3 were investigated by quantitative real-time PCR and western blot analysis. After treatment of 200 microM CoCl(2) for 24 h, RGC-5 cells showed a marked decrease of cell viability by approximately 30%, increased apoptosis rate and obvious decline in MMP, which could largely be reversed by the pretreatment of 1 microM pilocarpine mainly via the activation of muscarinic receptors. Meanwhile, pretreatment of 1 microM pilocarpine could significantly prevent CoCl(2)-induced HIF-1 alpha translocation from cytoplasm to nucleus and down-regulate the expression of HIF-1 alpha, p53, and BNIP3. These studies demonstrated that pilocarpine had effective protection against hypoxia-induced apoptosis in RGCs via muscarinic receptors and HIF-1 alpha pathway. The findings suggest that HIF-1 alpha pathway as a "master switch" may be used as a therapeutic target in the cholinergic treatment of glaucoma.

  18. Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Naoki [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kubota, Yoshitaka, E-mail: kubota-cbu@umin.ac.jp [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kosaka, Kentarou; Akita, Shinsuke; Sasahara, Yoshitarou; Kira, Tomoe [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kuroda, Masayuki [Center for Advanced Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Mitsukawa, Nobuyuki [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Bujo, Hideaki [Department of Clinical-Laboratory and Experimental-Research Medicine, Toho University, Sakura Medical Center, 564-1 Shimoshizu, Sakura-shi, Chiba, #285-8741 (Japan); Satoh, Kaneshige [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan)

    2015-08-07

    Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDR may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings.

  19. Predictive values of H.I.F.-1 alpha, H.I.F.-2 alpha and C.A. 9 expressions by prostate adenocarcinomas treated by exclusive irradiation. Ancillary study of the G.E.T.U.G. 06 protocol; Valeurs predictives des expressions de HIF-1 alpha, HIF-2 alpha et CA 9 par les adenocarcinomes de la prostate traites par irradiation exclusive. Etude ancillaire du protocole GETUG 06

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J.M.; Mazeron, J.J. [Groupe Hospitalier de la Pitie-Salpetriere, APHP, Service de Radiotherapie, 75 - Paris (France); Comperat, E. [Groupe Hospitalier de la Pitie-Salpetriere, APHP, Lab. d' Anatomie Pathologique, 75 - Paris (France); Beckendorf, V. [Centre Alexis-Vautrin, Dept. de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France); Bey, P. [Institut Curie, 75 - Paris (France); Jaillon, P. [Hopital Saint-Antoine, APHP, Service de Pharmacologie, 75 - Paris (France)

    2007-11-15

    The adenocarcinomas of the prostate are potentially hypoxic tumors. The strong expression of markers of hypoxia H.I.F.-2 alpha and C.A. 9 are independent predictor factors of biochemical relapse after exclusive radiotherapy. (N.C.)

  20. ENMD-1198, a novel tubulin-binding agent reduces HIF-1alpha and STAT3 activity in human hepatocellular carcinoma(HCC) cells, and inhibits growth and vascularization in vivo.

    Science.gov (United States)

    Moser, Christian; Lang, Sven A; Mori, Akira; Hellerbrand, Claus; Schlitt, Hans J; Geissler, Edward K; Fogler, William E; Stoeltzing, Oliver

    2008-07-23

    Hepatocellular carcinoma (HCC) represents a highly vascularized tumor entity and the process of angiogenesis is essential for the growth of HCC. Importantly, the pro-angiogenic transcription factors HIF-1alpha and STAT3 have been implicated in HCC progression, thus representing interesting targets for molecular targeted therapy. We hypothesized that therapeutic inhibition of HIF-1alpha could be achieved by using a novel tubulin-binding agent (ENMD-1198). ENMD-1198 is an analog of 2-methoxyestradiol (2ME2) with antiproliferative and antiangiogenic activity. The human HCC cell lines HUH-7 and HepG2 were used for experiments. Effects of ENMD-1198 on constitutive and inducible (hypoxia, growth factors) activation of signaling cascades, including HIF-1alpha and STAT3, were investigated by Western blotting. Changes in VEGF expression were determined by real-time PCR. Effects of ENMD-1198 on cancer cell migration and invasion were evaluated in in vitro-assays. The growth-inhibitory effects of ENMD-1198 (200 mg/kg/day) were determined in a subcutaneous tumor model (HUH-7). ENMD-1198 inhibited the phosphorylation of MAPK/Erk, PI-3K/Akt and FAK. Moreover, activation of HIF-1alpha and STAT3 was dramatically reduced by ENMD-1198, which resulted in lower VEGF mRNA expression (P < 0.05). In addition, tumor cell migratory and invasive properties were significantly inhibited (P < 0.05, for both). In vivo, treatment with ENMD-1198 led to a significant reduction in tumor growth, tumor vascularization, and numbers of proliferating tumor cells (P < 0.05 for all). The novel microtubule destabilizing agent ENMD-1198 is suitable for inhibiting HIF-1alpha and STAT3 in human HCC cells and leads to reduced tumor growth and vascularization in vivo. Hence, inhibition of HIF-1alpha and STAT3 could prove valuable for therapy of hepatocellular carcinoma.

  1. Prognostic significance of Ki67 proliferation index, HIF1 alpha index and microvascular density in patients with non-small cell lung cancer brain metastases

    Energy Technology Data Exchange (ETDEWEB)

    Berghoff, A.S. [Medical University of Vienna, Institute of Neurology, Vienna (Austria); Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Medical University of Vienna, Department of Medicine I, Vienna (Austria); Ilhan-Mutlu, A.; Preusser, M. [Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Medical University of Vienna, Department of Medicine I, Vienna (Austria); Woehrer, A.; Hainfellner, J.A. [Medical University of Vienna, Institute of Neurology, Vienna (Austria); Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Hackl, M. [Austrian National Cancer Registry, Statistics Austria, Vienna (Austria); Widhalm, G. [Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Medical University of Vienna, Department of Neurosurgery, Vienna (Austria); Dieckmann, K. [Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Medical University of Vienna, Department of Radiotherapy, Vienna (Austria); Melchardt, T. [Paracelsus Medical University Hospital Salzburg, Third Medical Department, Salzburg (Austria); Dome, B. [Medical University of Vienna, Department of Surgery, Vienna (Austria); Heinzl, H. [Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Medical University of Vienna, Center for Medical Statistics, Informatics, and Intelligent Systems, Vienna (Austria); Birner, P. [Medical University of Vienna, Comprehensive Cancer Center CNS Tumors Unit, Vienna (Austria); Medical University of Vienna, Institute of Clinical Pathology, Vienna (Austria)

    2014-07-15

    Survival upon diagnosis of brain metastases (BM) in patients with non-small cell lung cancer (NSCLC) is highly variable and established prognostic scores do not include tissue-based parameters. Patients who underwent neurosurgical resection as first-line therapy for newly diagnosed NSCLC BM were included. Microvascular density (MVD), Ki67 tumor cell proliferation index and hypoxia-inducible factor 1 alpha (HIF-1 alpha) index were determined by immunohistochemistry. NSCLC BM specimens from 230 patients (151 male, 79 female; median age 56 years; 199 nonsquamous histology) and 53/230 (23.0 %) matched primary tumor samples were available. Adjuvant whole-brain radiation therapy (WBRT) was given to 153/230 (66.5 %) patients after neurosurgical resection. MVD and HIF-1 alpha indices were significantly higher in BM than in matched primary tumors. In patients treated with adjuvant WBRT, low BM HIF-1 alpha expression was associated with favorable overall survival (OS), while among patients not treated with adjuvant WBRT, BM HIF-1 alpha expression did not correlate with OS. Low diagnosis-specific graded prognostic assessment score (DS-GPA), low Ki67 index, high MVD, low HIF-1 alpha index and administration of adjuvant WBRT were independently associated with favorable OS. Incorporation of tissue-based parameters into the commonly used DS-GPA allowed refined discrimination of prognostic subgroups. Ki67 index, MVD and HIF-1 alpha index have promising prognostic value in BM and should be validated in further studies. (orig.) [German] Die Ueberlebensprognose von Patienten mit zerebralen Metastasen eines nicht-kleinzelligen Lungenkarzinoms (NSCLC) ist sehr variabel. Bisher werden gewebsbasierte Parameter nicht in die prognostische Beurteilung inkludiert. Neurochirurgische Resektate zerebraler NSCLC-Metastasen wurden in dieser Studie untersucht. Die Gefaessdichte (''microvascular density'', MVD), der Ki67-Proliferationsindex sowie der HIF-1α-Index wurden mittels

  2. PGE1 analog alprostadil induces VEGF and eNOS expression in endothelial cells.

    Science.gov (United States)

    Haider, Dominik G; Bucek, Robert A; Giurgea, Aura G; Maurer, Gerald; Glogar, Helmut; Minar, Erich; Wolzt, Michael; Mehrabi, Mohammad R; Baghestanian, Mehrdad

    2005-11-01

    Endothelial nitric oxide synthase (eNOS), VEGF, and hypoxia-inducible factor 1-alpha (HIF-1alpha) are important regulators of endothelial function, which plays a role in the pathophysiology of heart failure (HF). PGE1 analog treatment in patients with HF elicits beneficial hemodynamic effects, but the precise mechanisms have not been investigated. We have investigated the effects of the PGE1 analog alprostadil on eNOS, VEGF, and HIF-1alpha expression in human umbilical vein endothelial cells (HUVEC) using RT-PCR and immunoblotting under normoxic and hypoxic conditions. In addition, we studied protein expression by immunohistochemical staining in explanted hearts from patients with end-stage HF, treated or untreated with systemic alprostadil. Alprostadil causes an upregulation of eNOS and VEGF protein and mRNA expression in HUVEC and decreases HIF-1alpha. Hypoxia potently increased eNOS, VEGF, and HIF-1alpha synthesis. The alprostadil-induced upregulation of eNOS and VEGF was prevented by inhibition of MAPKs with PD-98056 or U-0126. Consistently, the expression of eNOS and VEGF was increased, and HIF-1alpha was reduced in failing hearts treated with alprostadil. The potent effects of alprostadil on endothelial VEGF and eNOS synthesis may be useful for patients with HF where endothelial dysfunction is involved in the disease process.

  3. The relationships between hypoxia-dependent markers: HIF-1alpha, EPO and EPOR in colorectal cancer.

    Science.gov (United States)

    Baltaziak, Marek; Wincewicz, Andrzej; Kanczuga-Koda, Luiza; Lotowska, Joanna M; Koda, Mariusz; Sulkowska, Urszula; Baltaziak, Marcin; Podbielski, Monika; Sobaniec-Lotowska, Maria E; Sulkowski, Stanislaw

    2013-01-01

    Hypoxia triggers production of several cytoprotective proteins. Hypoxia-inducible factor 1alpha (HIF-1α) is a powerful stimulator of transcription of many genes, including erythropoietin (EPO) in hypoxia-affected cells. Recent data have also implicated signaling by EPO receptor (EPOR) as a new factor influencing tumor progression. The aim of the study was to detect by immunohistochemistry the presence of HIF-1α, EPO and EPOR in colorectal cancer (CRC) in reference to clinicopathological variables. We found the presence of the studied proteins in specimens of all 125 CRC patients which is suggestive of the occurrence of hypoxia in colorectal cancer tissues. The expression of HIF-1α correlated significantly with the presence of EPO and EPOR in all samples (P < 0.001, r = 0.549 and P < 0.001, r = 0.536, respectively). Significant correlations (from P < 0.024 to P < 0.001) were found in the analyses of CRC subgroups such as histopathological type tumor, tumor grade, tumor stage and patients with lymph nodes metastases. The same high significant correlations (P < 0.001) were observed in group of sex, age and tumor location. However, the values of the correlation coefficients (r) which usually ranged from 0.5 to 0.6 suggest the existence of independent or concurrent mechanism stimulating generation of these proteins in colorectal cancer.

  4. Interplay between VHL/HIF1alpha and Wnt/beta-catenin pathways during colorectal tumorigenesis.

    NARCIS (Netherlands)

    Giles, R.H.; Lolkema, M.P.; Snijckers, C.M.; Belderbos, M.; Groep, P. van der; Mans, D.A.; Beest, M. van; Noort, M. van; Goldschmeding, R.; Diest, P.J. van; Clevers, H.; Voest, E.E.

    2006-01-01

    Activation of the Wnt signaling pathway initiates the transformation of colorectal epithelial cells, although the transition to metastatic cancer requires angiogenesis. We have investigated the expression of the von Hippel-Lindau (VHL) tumor suppressor in the intestines from humans and mice. Here, w

  5. Radiation promotes malignant progression of glioma cells through HIF-1alpha stabilization.

    Science.gov (United States)

    Kim, Young-Heon; Yoo, Ki-Chun; Cui, Yan-Hong; Uddin, Nizam; Lim, Eun-Jung; Kim, Min-Jung; Nam, Seon-Young; Kim, In-Gyu; Suh, Yongjoon; Lee, Su-Jae

    2014-11-01

    Given its contribution to malignant phenotypes of cancer, tumor hypoxia has been considered as a potential therapeutic problem. In the stressful microenvironment condition, hypoxia inducible factor 1 (HIF1) is well known to mediate the transcriptional adaptation of cells to hypoxia and acts as a central player for the process of hypoxia-driven malignant cancer progression. Here, we found that irradiation causes the HIF1α protein to stabilize, even in normoxia condition through activation of p38 MAPK, thereby promoting angiogenesis in tumor microenvironment and infiltrative property of glioma cells. Notably, irradiation reduced hydroxylation of HIF1α through destabilization of prolyl hydroxylases (PHD)-2. Moreover, radiation also decreased the half-life of protein von Hippel-Lindau (pVHL), which is a specific E3 ligase for HIF1α. Of note, inhibition of p38 MAPK attenuated radiation-induced stabilization of HIF1α through destabilization of PHD-2 and pVHL. In agreement with these results, targeting of either p38 MAPK, HIF1α, pVHL or PHD-2 effectively mitigated the radiation-induced tube formation of human brain-derived micro-vessel endothelial cells (HB-MEC) and infiltration of glioma cells. Taken together, our findings suggest that targeting HIF1α in combination with ionizing radiation might increase the efficacy of radiotherapy for glioma treatment. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. HIF1alpha synergizes with glucocorticoids to promote BFU-E progenitor self-renewal.

    Science.gov (United States)

    Flygare, Johan; Rayon Estrada, Violeta; Shin, Chanseok; Gupta, Sumeet; Lodish, Harvey F

    2011-03-24

    With the aim of finding small molecules that stimulate erythropoiesis earlier than erythropoietin and that enhance erythroid colony-forming unit (CFU-E) production, we studied the mechanism by which glucocorticoids increase CFU-E formation. Using erythroid burst-forming unit (BFU-E) and CFU-E progenitors purified by a new technique, we demonstrate that glucocorticoids stimulate the earliest (BFU-E) progenitors to undergo limited self-renewal, which increases formation of CFU-E cells > 20-fold. Interestingly, glucocorticoids induce expression of genes in BFU-E cells that contain promoter regions highly enriched for hypoxia-induced factor 1α (HIF1α) binding sites. This suggests activation of HIF1α may enhance or replace the effect of glucocorticoids on BFU-E self-renewal. Indeed, HIF1α activation by a prolyl hydroxylase inhibitor (PHI) synergizes with glucocorticoids and enhances production of CFU-Es 170-fold. Because PHIs are able to increase erythroblast production at very low concentrations of glucocorticoids, PHI-induced stimulation of BFU-E progenitors thus represents a conceptually new therapeutic window for treating erythropoietin-resistant anemia.

  7. Validation of 2-mm tissue microarray technology in gastric cancer. Agreement of 2-mm TMAs and full sections for Glut-1 and Hif-1 alpha.

    Science.gov (United States)

    Berlth, Felix; Mönig, Stefan P; Schlösser, Hans A; Maus, Martin; Baltin, Christoph T H; Urbanski, Alexander; Drebber, Uta; Bollschweiler, Elfriede; Hölscher, Arnulf H; Alakus, Hakan

    2014-07-01

    Tissue Microarray (TMA) is a widely used method to perform high-throughput immunohistochemical analyses on different tissues by arraying small sample cores from paraffin-fixed tissues into a single paraffin block. TMA-technology has been validated on numerous cancer tissues and also for gastric cancer studies, although it has not been validated for this tumor tissue so far. The objective of this study was to assess, whether the 2-mm TMA-technology is able to provide representative samples of gastric cancer tissue. TMA paraffin blocks were constructed by means of 220 formalin-fixed and paraffin-embedded gastric cancer samples with a sample diameter of 2 mm. The agreement of immunohistochemical stainings of Glut-1 and Hif-1 alpha in TMA sections and the original full sections was calculated using kappa statistics and direct adjustment. The congruence was substantial for Glut-1 (kappa 0.64) and Hif-1 alpha (kappa 0.70), but with an agreement of only 71% and 52% within the marker-positive cases of the full-section slides. Due to tumor heterogeneity primarily, the TMA technology with a 2-mm sample core shows relevant limitations in gastric cancer tissue. Although being helpful for tissue screening purposes, the 2-mm TMA technology cannot be recommended as a method equal to full-section investigations in gastric cancer. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  8. Gene expression in the Andes; relevance to neurology at sea level.

    Science.gov (United States)

    Appenzeller, Otto; Minko, Tamara; Pozharov, Vitaly; Bonfichi, Maurizio; Malcovati, Luca; Gamboa, Jorge; Bernardi, Luciano

    2003-03-15

    Chronic mountain sickness (CMS), a maladaptation syndrome to chronic hypoxia, occurs in the Andes. Gene expression differences in Andeans could explain adaptation and maladaptation to hypoxia, both of which are relevant to neurology at sea level. Expression of genes responsive to cellular oxygen concentration, hypoxia-inducible factor-1alpha (HIF-1alpha), three splicing variants of vascular endothelial growth factor (VEGF) and von Hippel-Lindau protein (pVHL) was measured by reverse transcription polymerase chain reaction (RT-PCR) in 12 Cerro de Pasco (CP) (altitude 4338 m) natives and 15 CMS patients in CP. Thirteen high altitude natives living in Lima and five Lima natives were sea level controls. A CMS score (CMS-sc) was assigned clinically. Expression was related to the clinical assessment. High expression of HIF-1alpha and VEGF-121 was found in CMS (P<0.001). Samples from CP had higher expression than those from Lima (P<0.001). Expression of HIF-1alpha and VEGF-121 was related to age (P<0.001); adjusting for age did not abolish the group effect. Higher CMS-sc was related to expression independent of age (P<0.001). VEGF-165 and -189 were expressed only in CMS. Birth altitude had no effect on gene expression. pVHL was not quantifiable.HIF-1alpha and VEGF-121 participate in adaptation to hypoxia. The high levels may explain blood vessel proliferation in Andeans and hold lessons for patients at sea level. VEGF-165 expression suggests that it contributes to preservation of neuronal function in human chronic hypoxia. VHL mutations may mark those destined to develop neural crest tumors which are common in the Andes.

  9. Myc post-transcriptionally induces HIF1 protein and target gene expression in normal and cancer cells

    Science.gov (United States)

    Doe, Megan R.; Ascano, Janice; Kaur, Mandeep; Cole, Michael D.

    2012-01-01

    c-Myc is frequently overexpressed in tumors and plays an important role in the regulation of cancer metabolism. Hypoxia-inducible factor-1 (HIF1), the master regulator of the hypoxic response, enhances tumorigenesis and influences metabolism via upregulation of the glycolytic pathway and suppression of mitochondrial respiration. Together, deregulated Myc and HIF1 cooperate to lend metabolic advantages to proliferating cancer cells and contribute to the Warburg Effect. Here we show that overexpression of Myc significantly stabilizes the alpha subunit of HIF1 (HIF1alpha) under normoxic conditions and enhances HIF1alpha accumulation under hypoxic conditions in cells. Post-transcriptional regulation of HIF1α by Myc led to the induction of HIF1α gene targets. Normoxic HIF1α protein expression was also dependent on Myc. Functionally; HIF1α expression was required for Myc-induced anchorage-independent growth and cell proliferation. Myc-dependent stabilization of HIF1α involved either disruption of binding to the VHL complex or post-translational protein modifications. Taken together, our findings uncover a previously uncharacterized regulatory relationship between Myc and HIF1 that has important implications for cancer metabolism and development. PMID:22186139

  10. Pneumococcal infection of respiratory cells exposed to welding fumes; Role of oxidative stress and HIF-1 alpha

    Science.gov (United States)

    Grigg, Jonathan; Miyashita, Lisa

    2017-01-01

    Welders are more susceptible to pneumococcal pneumonia. The mechanisms are yet unclear. Pneumococci co-opt the platelet activating factor receptor (PAFR) to infect respiratory epithelial cells. We previously reported that exposure of respiratory cells to welding fumes (WF), upregulates PAFR–dependent pneumococcal infection. The signaling pathway for this response is unknown, however, in intestinal cells, hypoxia-inducible factor-1 α (HIF 1α) is reported to mediate PAFR-dependent infection. We sought to assess whether oxidative stress plays a role in susceptibility to pneumococcal infection via the platelet activating factor receptor. We also sought to evaluate the suitability of nasal epithelial PAFR expression in welders as a biomarker of susceptibility to infection. Finally, we investigated the generalisability of the effect of welding fumes on pneumococcal infection and growth using a variety of different welding fume samples. Nasal epithelial PAFR expression in welders and controls was analysed by flow cytometry. WF were collected using standard methodology. The effect of WF on respiratory cell reactive oxygen species production, HIF-1α expression, and pneumococcal infection was determined using flow cytometry, HIF-1α knockdown and overexpression, and pneumococcal infection assays. We found that nasal PAFR expression is significantly increased in welders compared with controls and that WF significantly increased reactive oxygen species production, HIF-1α and PAFR expression, and pneumococcal infection of respiratory cells. In unstimulated cells, HIF-1α knockdown decreased PAFR expression and HIF-1α overexpression increased PAFR expression. However, in knockdown cells pneumococcal infection was paradoxically increased and in overexpressing cells infection was unaffected. Nasal epithelial PAFR expression may be used as a biomarker of susceptibility to pneumococcal infection in order to target individuals, particularly those at high risk such as welders

  11. HIF1-alpha overexpression indicates a good prognosis in early stage squamous cell carcinomas of the oral floor

    Directory of Open Access Journals (Sweden)

    Joos Ulrich

    2005-07-01

    Full Text Available Abstract Background Hypoxia-inducible factor 1 (HIF-1 is a transcription factor, which plays a central role in biologic processes under hypoxic conditions, especially concerning tumour angiogenesis. HIF-1α is the relevant, oxygen-dependent subunit and its overexpression has been associated with a poor prognosis in a variety of malignant tumours. Therefore, HIF-1α expression in early stage oral carcinomas was evaluated in relation to established clinico-pathological features in order to determine its value as a prognostic marker. Methods 85 patients with histologically proven surgically treated T1/2 squamous cell carcinoma (SCC of the oral floor were eligible for the study. Tumor specimens were investigated by means of tissue micro arrays (TMAs and immunohistochemistry for the expression of HIF-1. Correlations between clinical features and the expression of HIF-1 were evaluated by Kaplan-Meier curves, log-rank tests and multivariate Cox regression analysis. Results HIF-1α was frequently overexpressed in a probably non-hypoxia related fashion. The expression of HIF-1α was related with a significantly improved 5-year survival rate (p Conclusion HIF-1α overexpression is an indicator of favourable prognosis in T1 and T2 SCC of the oral floor. Node negative patients lacking HIF-1α expression may therefore be considered for adjuvant radiotherapy.

  12. Regulation of HIF-1-Alpha, miR-200, and Markers of Cancer Stem Cells by CDF Under Hypoxic Condition

    Science.gov (United States)

    2012-04-01

    Ali,S., Kong,D., Banerjee,S., Ahmad,A., Li,Y., Azmi,A.S., Miele ,L. and Sarkar,F.H. Over-expression of FoxM1 leads to epithelial-mesenchymal...Ahmad,A., Banerjee,S., Azmi,A.S., Miele ,L. and Sarkar,F.H. Notch-1 induces epithelial-mesenchymal transition consistent with cancer stem cell

  13. PI3K/Akt contributes to increased expression of Toll-like receptor 4 in macrophages exposed to hypoxic stress

    Energy Technology Data Exchange (ETDEWEB)

    Kim, So Young; Jeong, Eunshil; Joung, Sun Myung [School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Lee, Joo Young, E-mail: joolee@catholic.ac.kr [School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); College of Pharmacy, The Catholic University of Korea, Bucheon 420-743 (Korea, Republic of)

    2012-03-16

    Highlights: Black-Right-Pointing-Pointer Hypoxic stress-induced TLR4 expression is mediated by PI3K/Akt in macrophages. Black-Right-Pointing-Pointer PI3K/Akt regulated HIF-1 activation leading to TLR4 expression. Black-Right-Pointing-Pointer p38 mitogen-activated protein kinase was not involved in TLR4 expression by hypoxic stress. Black-Right-Pointing-Pointer Sulforaphane suppressed hypoxia-mediated TLR4 expression by inhibiting PI3K/Akt. -- Abstract: Toll-like receptors (TLRs) play critical roles in triggering immune and inflammatory responses by detecting invading microbial pathogens and endogenous danger signals. Increased expression of TLR4 is implicated in aggravated inflammatory symptoms in ischemic tissue injury and chronic diseases. Results from our previous study showed that TLR4 expression was upregulated by hypoxic stress mediated by hypoxia-inducible factor-1 (HIF-1) at a transcriptional level in macrophages. In this study, we further investigated the upstream signaling pathway that contributed to the increase of TLR4 expression by hypoxic stress. Either treatment with pharmacological inhibitors of PI3K and Akt or knockdown of Akt expression by siRNA blocked the increase of TLR4 mRNA and protein levels in macrophages exposed to hypoxia and CoCl{sub 2}. Phosphorylation of Akt by hypoxic stress preceded nuclear accumulation of HIF-1{alpha}. A PI3K inhibitor (LY294002) attenuated CoCl{sub 2}-induced nuclear accumulation and transcriptional activation of HIF-1{alpha}. In addition, HIF-1{alpha}-mediated upregulation of TLR4 expression was blocked by LY294002. Furthermore, sulforaphane suppressed hypoxia- and CoCl{sub 2}-induced upregulation of TLR4 mRNA and protein by inhibiting PI3K/Akt activation and the subsequent nuclear accumulation and transcriptional activation of HIF-1{alpha}. However, p38 was not involved in HIF-1{alpha} activation and TLR4 expression induced by hypoxic stress in macrophages. Collectively, our results demonstrate that PI3K

  14. Heat Shock Protein 90 (Hsp90 Expression and Breast Cancer

    Directory of Open Access Journals (Sweden)

    Christos A. Papadimitriou

    2012-09-01

    Full Text Available Hsp90 is an abundant protein in mammalian cells. It forms several discrete complexes, each containing distinct groups of co-chaperones that assist protein folding and refolding during stress, protein transport and degradation. It interacts with a variety of proteins that play key roles in breast neoplasia including estrogen receptors, tumor suppressor p53 protein, angiogenesis transcription factor HIF-1alpha, antiapoptotic kinase Akt, Raf-1 MAP kinase and a variety of receptor tyrosine kinases of the erbB family. Elevated Hsp90 expression has been documented in breast ductal carcinomas contributing to the proliferative activity of breast cancer cells; whilst a significantly decreased Hsp90 expression has been shown in infiltrative lobular carcinomas and lobular neoplasia. Hsp90 overexpression has been proposed as a component of a mechanism through which breast cancer cells become resistant to various stress stimuli. Therefore, pharmacological inhibition of HSPs can provide therapeutic opportunities in the field of cancer treatment. 17-allylamino,17-demethoxygeldanamycin is the first Hsp90 inhibitor that has clinically been investigated in phase II trial, yielding promising results in patients with HER2-overexpressing metastatic breast cancer, whilst other Hsp90 inhibitors (retaspimycin HCL, NVP-AUY922, NVP-BEP800, CNF2024/BIIB021, SNX-5422, STA-9090, etc. are currently under evaluation.

  15. l-carnosine dipeptide overcomes acquired resistance to 5-fluorouracil in HT29 human colon cancer cells via downregulation of HIF1-alpha and induction of apoptosis.

    Science.gov (United States)

    Iovine, Barbara; Guardia, Francesca; Irace, Carlo; Bevilacqua, Maria Assunta

    2016-08-01

    Hypoxia-inducible factor (HIF-1α) protein is over-expressed in many human cancers and is a major cause of resistance to drugs. HIF-1α up-regulation decreases the effectiveness of several anticancer agents, including 5-fluorouracil (5-FU), because it induces the expression of drug efflux transporters, alters DNA repair mechanisms and modifies the balance between pro- and antiapoptotic factors. These findings suggest that inhibition of HIF-1α activity may sensitize cancer cells to cytotoxic drugs. We previously reported that l-carnosine reduces HIF-1α expression by inhibiting the proliferation of colon cancer cells. In the present study we investigated the effect of l-carnosine on HT29 colon cancer cells with acquired resistance to 5-FU. We found that l-carnosine reduces colon cancer cell viability, decreases HIF-1α and multi-drug resistant protein MDR1-pg expression, and induces apoptosis. Moreover, the l-carnosine/5-FU combination lowers the expression of some chemoresistance markers. The combination index evaluated in vitro on the HT29-5FU cell line by median drug effect analysis reveals a significant synergistic effect.

  16. Gene Expression Programs in Response to Hypoxia: Cell Type Specificity and Prognostic Significance in Human Cancers.

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available BACKGROUND: Inadequate oxygen (hypoxia triggers a multifaceted cellular response that has important roles in normal physiology and in many human diseases. A transcription factor, hypoxia-inducible factor (HIF, plays a central role in the hypoxia response; its activity is regulated by the oxygen-dependent degradation of the HIF-1alpha protein. Despite the ubiquity and importance of hypoxia responses, little is known about the variation in the global transcriptional response to hypoxia among different cell types or how this variation might relate to tissue- and cell-specific diseases. METHODS AND FINDINGS: We analyzed the temporal changes in global transcript levels in response to hypoxia in primary renal proximal tubule epithelial cells, breast epithelial cells, smooth muscle cells, and endothelial cells with DNA microarrays. The extent of the transcriptional response to hypoxia was greatest in the renal tubule cells. This heightened response was associated with a uniquely high level of HIF-1alpha RNA in renal cells, and it could be diminished by reducing HIF-1alpha expression via RNA interference. A gene-expression signature of the hypoxia response, derived from our studies of cultured mammary and renal tubular epithelial cells, showed coordinated variation in several human cancers, and was a strong predictor of clinical outcomes in breast and ovarian cancers. In an analysis of a large, published gene-expression dataset from breast cancers, we found that the prognostic information in the hypoxia signature was virtually independent of that provided by the previously reported wound signature and more predictive of outcomes than any of the clinical parameters in current use. CONCLUSIONS: The transcriptional response to hypoxia varies among human cells. Some of this variation is traceable to variation in expression of the HIF1A gene. A gene-expression signature of the cellular response to hypoxia is associated with a significantly poorer prognosis

  17. Tissue expression and plasma levels of adrenomedullin in renal cancer patients

    DEFF Research Database (Denmark)

    Michelsen, Jens; Thiesson, Helle; Walter, Steen;

    2006-01-01

    The peptide AM (adrenomedullin) is stimulated by hypoxia through HIF-1 (hypoxia-inducible factor-1). The majority of human CC-RCCs (clear cell renal cell carcinomas) display mutations in the tumour suppressor protein von Hippel-Lindau, which leads to constitutively elevated HIF-1. We hypothesized......RNA and peptide expression in tissue and AM plasma concentration were determined. HIF-1alpha was localized in tissue by immunohistochemistry. AM mRNA was elevated in CC-RCC compared with adjacent renal cortex (6-fold, n=18; P

  18. Muscle-specific expression of hypoxia-inducible factor in human skeletal muscle

    DEFF Research Database (Denmark)

    Mounier, Rémi; Pedersen, Bente Klarlund; Plomgaard, Peter

    2010-01-01

    from triceps brachii (characterized by a high proportion of type II fibres), from soleus (characterized by a high proportion of type I fibres) and from vastus lateralis (characterized by an equal proportion of type I and II fibres). The hypothesis was that type I muscle fibres would have lower HIF-1...... a significantly higher VEGF protein content than vastus lateralis and triceps muscle. In conclusion, we have shown that there are muscle-specific differences in HIF-1alpha and VEGF expression within human skeletal muscle at rest in normoxic conditions. Recent results, when combined with the findings described...

  19. Class II histone deacetylases are associated with VHL-independent regulation of hypoxia-inducible factor 1 alpha.

    Science.gov (United States)

    Qian, David Z; Kachhap, Sushant K; Collis, Spencer J; Verheul, Henk M W; Carducci, Michael A; Atadja, Peter; Pili, Roberto

    2006-09-01

    Hypoxia-inducible factor 1 alpha (HIF-1 alpha) plays a critical role in transcriptional gene activation involved in tumor angiogenesis. A novel class of agents, the histone deacetylase (HDAC) inhibitors, has been shown to inhibit tumor angiogenesis and HIF-1 alpha protein expression. However, the molecular mechanism responsible for this inhibition remains to be elucidated. In the current study, we investigated the molecular link between HIF-1 alpha inhibition and HDAC inhibition. Treatment of the VHL-deficient human renal cell carcinoma cell line UMRC2 with the hydroxamic HDAC inhibitor LAQ824 resulted in a dose-dependent inhibition of HIF-1 alpha protein via a VHL-independent mechanism and reduction of HIF-1 alpha transcriptional activity. HIF-1 alpha inhibition by LAQ824 was associated with HIF-1 alpha acetylation and polyubiquitination. HIF-1 alpha immunoprecipitates contained HDAC activity. Then, we tested different classes of HDAC inhibitors with diverse inhibitory activity of class I versus class II HDACs and assessed their capability of targeting HIF-1 alpha. Hydroxamic acid derivatives with known activity against both class I and class II HDACs were effective in inhibiting HIF-1 alpha at low nanomolar concentrations. In contrast, valproic acid and trapoxin were able to inhibit HIF-1 alpha only at concentrations that are effective against class II HDACs. Coimmunoprecipitation studies showed that class II HDAC4 and HDAC6 were associated with HIF-1 alpha protein. Inhibition by small interfering RNA of HDAC4 and HDAC6 reduced HIF-1 alpha protein expression and transcriptional activity. Taken together, these results suggest that class II HDACs are associated with HIF-1 alpha stability and provide a rationale for targeting HIF-1 alpha with HDAC inhibitors against class II isozymes.

  20. HIF-1 attenuates Ref-1 expression in endothelial cells: reversal by siRNA and inhibition of geranylgeranylation.

    Science.gov (United States)

    Loboda, Agnieszka; Stachurska, Anna; Dorosz, Jerzy; Zurawski, Marek; Wegrzyn, Joanna; Kozakowska, Magdalena; Jozkowicz, Alicja; Dulak, Jozef

    2009-01-01

    Redox factor-1 (Ref-1), a multifunctional protein with DNA repairing activities, plays a cytoprotective function by post-translational redox modification of numerous transcription factors, including hypoxia inducible factor-1 (HIF-1). In the present study, activation of HIF-1 by hypoxia and dimethyloxaloylglycine (DMOG), a hypoxia mimic, diminished Ref-1 mRNA and protein expression in human microvascular endothelial cells (HMEC-1). Similarly, adenoviral delivery of the stabilized form of HIF-1alpha decreased Ref-1 mRNA and protein levels. Accordingly, HIF-1alpha siRNA abolished the hypoxia-induced inhibition of Ref-1 expression, indicating the role of HIF-1 in down-regulation of Ref-1. Also, translocation of Ref-1 from nucleus to cytoplasm after HIF-1 activation was noted. Interestingly, we observed the restoration of Ref-1 expression in hypoxia by pharmacologically relevant doses of atorvastatin. This effect was dependent on the inhibition of protein geranylgeranylation, but not farnesylation, as only the inhibitor of the former but not the latter prenylation step restored the Ref-1 expression. The regulation of Ref-1 by statins may be considered as a novel mechanism of their beneficial effects on endothelium.

  1. Hypoxia inducible factor 1-alpha (HIF-1 alpha is induced during reperfusion after renal ischemia and is critical for proximal tubule cell survival.

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    Elisa Conde

    Full Text Available Acute tubular necrosis (ATN caused by ischemia/reperfusion (I/R during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α, using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant.

  2. The ROS-induced cytotoxicity of ascorbate is attenuated by hypoxia and HIF-1alpha in the NCI60 cancer cell lines.

    Science.gov (United States)

    Sinnberg, Tobias; Noor, Seema; Venturelli, Sascha; Berger, Alexander; Schuler, Paul; Garbe, Claus; Busch, Christian

    2014-03-01

    Intravenous application of high-dose ascorbate is used in complementary palliative medicine to treat cancer patients. Pharmacological doses of ascorbate in the mM range induce cytotoxicity in cancer cells mediated by reactive oxygen species (ROS), namely hydrogen peroxide and ascorbyl radicals. However, little is known about intrinsic or extrinsic factors modulating this ascorbate-mediated cytotoxicity. Under normoxia and hypoxia, ascorbate IC50 values were determined on the NCI60 cancer cells. The cell cycle, the influence of cobalt chloride-induced hypoxia-inducible factor-1α (HIF-1α) and the glucose transporter 1 (GLUT-1) expression (a pro-survival HIF-1α-downstream-target) were analysed after ascorbate exposure under normoxic and hypoxic conditions. The amount of ascorbyl radicals increased with rising serum concentrations. Hypoxia (0.1% O2 ) globally increased the IC50 of ascorbate in the 60 cancer cell lines from 4.5 ± 3.6 mM to 10.1 ± 5.9 mM (2.2-fold increase, P ascorbate. This ascorbate resistance depended on HIF-1α-signalling, but did not correlate with cell line-specific expression of the ascorbate transporter GLUT-1. However, under normoxic and hypoxic conditions, ascorbate treatment at the individual IC50 reduced the expression of GLUT-1 in the cancer cells. Our data show a ROS-induced, HIF-1α- and O2 -dependent cytotoxicity of ascorbate on 60 different cancer cells. This suggests that for clinical application, cancer patients should additionally be oxygenized to increase the cytotoxic efficacy of ascorbate.

  3. Reduction of macrophage infiltration and chemoattractant gene expression changes in white adipose tissue of morbidly obese subjects after surgery-induced weight loss.

    Science.gov (United States)

    Cancello, Raffaella; Henegar, Corneliu; Viguerie, Nathalie; Taleb, Soraya; Poitou, Christine; Rouault, Christine; Coupaye, Muriel; Pelloux, Veronique; Hugol, Danielle; Bouillot, Jean-Luc; Bouloumié, Anne; Barbatelli, Giorgio; Cinti, Saverio; Svensson, Per-Arne; Barsh, Gregory S; Zucker, Jean-Daniel; Basdevant, Arnaud; Langin, Dominique; Clément, Karine

    2005-08-01

    In human obesity, the stroma vascular fraction (SVF) of white adipose tissue (WAT) is enriched in macrophages. These cells may contribute to low-grade inflammation and to its metabolic complications. Little is known about the effect of weight loss on macrophages and genes involved in macrophage attraction. We examined subcutaneous WAT (scWAT) of 7 lean and 17 morbidly obese subjects before and 3 months after bypass surgery. Immunomorphological changes of the number of scWAT-infiltrating macrophages were evaluated, along with concomitant changes in expression of SVF-overexpressed genes. The number of scWAT-infiltrating macrophages before surgery was higher in obese than in lean subjects (HAM56+/CD68+; 22.6 +/- 4.3 vs. 1.4 +/- 0.6%, P attraction (monocyte chemotactic protein [MCP]-1, plasminogen activator urokinase receptor [PLAUR], and colony-stimulating factor [CSF]-3) and hypoxia (hypoxia-inducible factor-1alpha [HIF-1alpha]), expression of which increases in obesity and decreases after surgery, were predominantly expressed in the SVF. We show that improvement of the inflammatory profile after weight loss is related to a reduced number of macrophages in scWAT. MCP-1, PLAUR, CSF-3, and HIF-1alpha may play roles in the attraction of macrophages in scWAT.

  4. Differential gene expression in human granulosa cells from recombinant FSH versus human menopausal gonadotropin ovarian stimulation protocols

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    Bietz Mandi G

    2010-03-01

    Full Text Available Abstract Background The study was designed to test the hypothesis that granulosa cell (GC gene expression response differs between recombinant FSH and human menopausal gonadotropin (hMG stimulation regimens. Methods Females Results After exclusions, 1736 genes exhibited differential expression between groups. Over 400 were categorized as signal transduction genes, ~180 as transcriptional regulators, and ~175 as enzymes/metabolic genes. Expression of selected genes was confirmed by RT-PCR. Differentially expressed genes included A kinase anchor protein 11 (AKAP11, bone morphogenetic protein receptor II (BMPR2, epidermal growth factor (EGF, insulin-like growth factor binding protein (IGFBP-4, IGFBP-5, and hypoxia-inducible factor (HIF-1 alpha. Conclusions Results suggest that major differences exist in the mechanism by which pure FSH alone versus FSH/LH regulate gene expression in preovulatory GC that could impact oocyte maturity and developmental competence.

  5. Expression and function of hypoxia inducible factor-1 alpha in human melanoma under non-hypoxic conditions

    Directory of Open Access Journals (Sweden)

    Joshi Sandeep S

    2009-11-01

    Full Text Available Abstract Background Hypoxia inducible factor-1 alpha (HIF-1α protein is rapidly degraded under normoxic conditions. When oxygen tensions fall HIF-1α protein stabilizes and transactivates genes involved in adaptation to hypoxic conditions. We have examined the normoxic expression of HIF-1α RNA and protein in normal human melanocytes and a series of human melanoma cell lines isolated from radial growth phase (RGP, vertical growth phase (VGP and metastatic (MET melanomas. Results HIF-1α mRNA and protein was increased in RGP vs melanocytes, VGP vs RGP and MET vs VGP melanoma cell lines. We also detected expression of a HIF-1α mRNA splice variant that lacks part of the oxygen-dependent regulation domain in WM1366 and WM9 melanoma cells. Over-expression of HIF-1α and its splice variant in the RGP cell line SbCl2 resulted in a small increase in soft agar colony formation and a large increase in matrigel invasion relative to control transfected cells. Knockdown of HIF-1α expression by siRNA in the MET WM9 melanoma cell line resulted in a large decrease in both soft agar colony formation and matrigel invasion relative to cells treated with non-specific siRNA. There is a high level of ERK1/2 phosphorylation in WM9 cells, indicating an activated Ras-Raf-MEK-ERK1/2 MAPK pathway. Treatment of WM9 cells with 30 μM U0126 MEK inhibitor, decreased ERK1/2 phosphorylation and resulted in a decrease in HIF-1α expression. However, a 24 h treatment with 10 μM U0126 totally eliminated Erk1/2 phosphorylation, but did not change HIF-1alpha levels. Furthermore, siRNA knockdown of MEK siRNA did not change HIF-1alpha levels. Conclusion We speculate that metabolic products of U0126 decrease HIF-1alpha expression through "off target" effects. Overall our data suggest that increased HIF-1α expression under normoxic conditions contributes to some of the malignant phenotypes exhibited by human melanoma cells. The expanded role of HIF-1α in melanoma biology increases

  6. Tasquinimod (ABR-215050, a quinoline-3-carboxamide anti-angiogenic agent, modulates the expression of thrombospondin-1 in human prostate tumors

    Directory of Open Access Journals (Sweden)

    Isaacs John T

    2010-05-01

    Full Text Available Abstract Background The orally active quinoline-3-carboxamide tasquinimod [ABR-215050; CAS number 254964-60-8, which currently is in a phase II-clinical trial in patients against metastatic prostate cancer, exhibits anti-tumor activity via inhibition of tumor angiogenesis in human and rodent tumors. To further explore the mode of action of tasquinimod, in vitro and in vivo experiments with gene microarray analysis were performed using LNCaP prostate tumor cells. The array data were validated by real-time semiquantitative reversed transcriptase polymerase chain reaction (sqRT-PCR and protein expression techniques. Results One of the most significant differentially expressed genes both in vitro and in vivo after exposure to tasquinimod, was thrombospondin-1 (TSP1. The up-regulation of TSP1 mRNA in LNCaP tumor cells both in vitro and in vivo correlated with an increased expression and extra cellular secretion of TSP1 protein. When nude mice bearing CWR-22RH human prostate tumors were treated with oral tasquinimod, there was a profound growth inhibition, associated with an up-regulation of TSP1 and a down- regulation of HIF-1 alpha protein, androgen receptor protein (AR and glucose transporter-1 protein within the tumor tissue. Changes in TSP1 expression were paralleled by an anti-angiogenic response, as documented by decreased or unchanged tumor tissue levels of VEGF (a HIF-1 alpha down stream target in the tumors from tasquinimod treated mice. Conclusions We conclude that tasquinimod-induced up-regulation of TSP1 is part of a mechanism involving down-regulation of HIF1α and VEGF, which in turn leads to reduced angiogenesis via inhibition of the "angiogenic switch", that could explain tasquinimods therapeutic potential.

  7. Expression of hypoxia-inducible factor 1 alpha and its downstream targets in fibroepithelial tumors of the breast

    NARCIS (Netherlands)

    Kuijper, Arno; Groep, P. van der; Wall, E. van der; Diest, P.J. van

    2005-01-01

    INTRODUCTION Hypoxia-inducible factor 1 (HIF-1) alpha and its downstream targets carbonic anhydrase IX (CAIX) and vascular endothelial growth factor (VEGF) are key factors in the survival of proliferating tumor cells in a hypoxic microenvironment. We studied the expression and prognostic relevance o

  8. Hypoxia-inducible factor-1 alpha, in association with inflammation, angiogenesis and MYC, is a critical prognostic factor in patients with HCC after surgery

    Directory of Open Access Journals (Sweden)

    Zhou Jian

    2009-12-01

    Full Text Available Abstract Background Despite well-studied tumor hypoxia in laboratory, little is known about the association with other pathophysiological events in the clinical view. We investigated the prognostic value of hypoxia-inducible factor-1 alpha (HIF-1alpha in hepatocellular carcinoma (HCC, and its correlations with inflammation, angiogenesis and MYC oncogene. Methods In a random series of 110 HCC patients, the mRNA of HIF-1alpha, inflammation related factors (COX-2, MMP7 and MMP9, angiogenesis related factors (VEGF and PDGFRA and MYC in tumor tissue were detected by real-time RT-PCR and HIF-1alpha protein was assessed by immunohistochemistry. The correlations between HIF-1alpha mRNA and the factors mentioned previously, the relationship between HIF-1alpha and clinicopathologic features, and the prognostic value were analyzed. Results The expression of both HIF-1alpha mRNA and protein in HCC were independent prognostic factors for overall survival (OS (P = 0.012 and P = 0.021, respectively and disease-free survival (DFS (P = 0.004 and P = 0.007, respectively as well. Besides, the high expression of HIF-1alpha mRNA and protein proposed an advanced BCLC stage and more incidence of vascular invasion. The mRNA of HIF-1alpha had significantly positive correlations to that of COX-2, PDGFRA, MMP7, MMP9, MYC, except VEGF. In addition to HIF-1alpha, COX-2 and PDGFRA were also independent prognosticators for OS (P = 0.004 and P = 0.010, respectively and DFS (P = 0.010 and P = 0.038, respectively. Conclusion HIF-1alpha in HCC plays an important role in predicting patient outcome. It may influence HCC biological behaviors and affect the tumor inflammation, angiogenesis and act in concert with the oncogene MYC. Attaching importance to HIF-1alpha in HCC may improve the prognostic and therapeutic technique.

  9. Reversing the Multidrug Resistance of Human Pulmonary Adenocarcinoma Cells by RNA Interference Targeting HIF-1 alpha Gene%RNA干扰沉默缺氧诱导因子1α逆转肺癌细胞耐药性

    Institute of Scientific and Technical Information of China (English)

    刘胜岗; 陈琼; 何白梅; 陈莹; 聂华萍; 梁伟军

    2011-01-01

    Objective: To reverse the multidrug resistant (MDR) phenotype of human lung cancer cells by small interference RNA (siRNA) technique targeting hypoxia-inducible factor-lα (HIF-1α) gene. Methods: Small interference RNA eukaryotic expression vector targeting HIF-1αgene was constructed and transfected into human adenocarcinoma A549/DDP cells by liposome technique. The mRNA and protein expression levels of HIF-1α, MDR-1 and MRP were investigated by RT-PCR and immuocytochemistry. The mortality of cells was observed by MTT in different groups treated with cisplatin of different concentrations. Results: mRNA and protein levels of HIF-lα, MDR-1 and MRP were significantly decreased in HIF-1α siRNA group. The MTT assays showed the mortality in HIF-1α siRNA group was significantly higher than that in non-transfected group (P <0.05). The negative siRNA transfection did not affect the resistance of tumor cells. Conclusion: HIF-1α siRNA significantly reduced the expression ofHIF-1α, MDR-1 and MRP in A549/DDP cells and thus played a role in reversing drug resistance.%目的:观察RNA干扰沉默缺氧诱导因子1α(HIF-1α)对肺癌细胞耐药性的影响.方法:构建靶向HIF-1α小干扰RNA基因,并转染到人肺腺癌耐顺铂细胞株A549/DDP细胞中.逆转录聚合酶链反应RT-PCR)检测细胞的HIF-1α、多药耐药基因1(MDR-1)以多药耐药相关蛋白基因(MRP)mRNA变化,免疫细胞化学法观察干扰后HIF-1α、P-糖蛋白以及MRP蛋白的变化.MTT法检测不同浓度的顺铂作用下细胞死亡率.结果:HIF-1α siRNA组中HIF-1α、MDR-1、MRPmRNA水平显著降低(P<0.05),且蛋白水平也显著下降(P<0.05).HIF-1αsiRNA组细胞死亡率较未转染组均明显增高(P<0.05),转染siRNA阴性组不影响肿瘤细胞的耐药性.结论:HIF-1αsiRNA可显著降低A549/DDP细胞中HIF-1α、MDR-1、MRP表达,从而起到逆转肺腺癌A549/DDP细胞的耐药作用.

  10. Prostaglandin E2 induces hypoxia-inducible factor-1alpha stabilization and nuclear localization in a human prostate cancer cell line.

    Science.gov (United States)

    Liu, Xin Hua; Kirschenbaum, Alexander; Lu, Min; Yao, Shen; Dosoretz, Amy; Holland, James F; Levine, Alice C

    2002-12-20

    Hypoxia-induced up-regulation of vascular endothelial growth factor (VEGF) expression is a critical event leading to tumor neovascularization. Hypoxia stimulates hypoxia-inducible factor-1alpha (HIF-1alpha), a transcriptional activator of VEGF. Cyclooxygenase (COX)-2, an inducible enzyme that catalyzes the formation of prostaglandins (PGs) from arachidonic acid, is also induced by hypoxia. We reported previously that COX-2 inhibition prevents hypoxic up-regulation of VEGF in human prostate cancer cells and that prostaglandin E(2) (PGE(2)) restores hypoxic effects on VEGF. We hypothesized that PGE(2) mediates hypoxic effects on VEGF by modulating HIF-1alpha expression. Addition of PGE(2) to PC-3ML human prostate cancer cells had no effect on HIF-1alpha mRNA levels. However, PGE(2) significantly increased HIF-1alpha protein levels, particularly in the nucleus. This effect of PGE(2) largely results from the promotion of HIF-1alpha translocation from the cytosol to the nucleus. PGE(2) addition to PC-3 ML cells transfected with a GFP-HIF-1alpha vector induced a time-dependent nuclear accumulation of the HIF-1alpha protein. Two selective COX-2 inhibitors, meloxicam and NS398, decreased HIF-1alpha levels and nuclear localization, under both normoxic and hypoxic conditions. Of several prostaglandins tested, only PGE(2) reversed the effects of a COX-2 inhibitor in hypoxic cells. Finally, PGE(2) effects on HIF-1alpha were specifically inhibited by PD98059 (a MAPK inhibitor). These data demonstrate that PGE(2) production via COX-2-catalyzed pathway plays a critical role in HIF-1alpha regulation by hypoxia and imply that COX-2 inhibitors can prevent hypoxic induction of HIF-mediated gene transcription in cancer cells.

  11. ENMD-1198, a novel tubulin-binding agent reduces HIF-1alpha and STAT3 activity in human hepatocellular carcinoma(HCC cells, and inhibits growth and vascularization in vivo

    Directory of Open Access Journals (Sweden)

    Schlitt Hans J

    2008-07-01

    Full Text Available Abstract Background Hepatocellular carcinoma (HCC represents a highly vascularized tumor entity and the process of angiogenesis is essential for the growth of HCC. Importantly, the pro-angiogenic transcription factors HIF-1α and STAT3 have been implicated in HCC progression, thus representing interesting targets for molecular targeted therapy. We hypothesized that therapeutic inhibition of HIF-1α could be achieved by using a novel tubulin-binding agent (ENMD-1198. ENMD-1198 is an analog of 2-methoxyestradiol (2ME2 with antiproliferative and antiangiogenic activity. Methods The human HCC cell lines HUH-7 and HepG2 were used for experiments. Effects of ENMD-1198 on constitutive and inducible (hypoxia, growth factors activation of signaling cascades, including HIF-1α and STAT3, were investigated by Western blotting. Changes in VEGF expression were determined by real-time PCR. Effects of ENMD-1198 on cancer cell migration and invasion were evaluated in in vitro-assays. The growth-inhibitory effects of ENMD-1198 (200 mg/kg/day were determined in a subcutaneous tumor model (HUH-7. Results ENMD-1198 inhibited the phosphorylation of MAPK/Erk, PI-3K/Akt and FAK. Moreover, activation of HIF-1α and STAT3 was dramatically reduced by ENMD-1198, which resulted in lower VEGF mRNA expression (P In vivo, treatment with ENMD-1198 led to a significant reduction in tumor growth, tumor vascularization, and numbers of proliferating tumor cells (P Conclusion The novel microtubule destabilizing agent ENMD-1198 is suitable for inhibiting HIF-1α and STAT3 in human HCC cells and leads to reduced tumor growth and vascularization in vivo. Hence, inhibition of HIF-1α and STAT3 could prove valuable for therapy of hepatocellular carcinoma.

  12. Hypoxia induces a hedgehog response mediated by HIF-1 alpha

    NARCIS (Netherlands)

    Bijlsma, Maarten F.; Groot, Angelique P.; Oduro, Jeremiah P.; Franken, Rutger J.; Schoenmakers, Saskia H. H. F.; Peppelenbosch, Maikel P.; Spek, C. Arnold

    2009-01-01

    Recently, it has become clear that the developmental hedgehog pathway is activated in ischaemic adult tissue where it aids in salvaging damaged tissue. The exact driving force for the initial hedgehog response is unclear and as most physiological and cellular processes are disturbed in ischaemic tis

  13. Site-specific gene expression patterns in oral cancer.

    Science.gov (United States)

    Frohwitter, Gesche; Buerger, Horst; Korsching, Eberhard; van Diest, Paul J; Kleinheinz, Johannes; Fillies, Thomas

    2017-05-10

    Squamous cell carcinomas (SCCs) are the most prevalent malignant tumours within the head and neck. Evidence exists that distinct genes are differentially regulated in SCCs of the oral cavity compared to other head and neck regions. Given this background, the aim of this study was to investigate whether such tumour site-specific gene expression can also be observed in different localizations within the oral cavity. Using tissue microarrays (TMAs), we investigated 76 SCCs of the floor of the mouth, 49 SCCs of the tongue and 68 SCCs of other anatomic regions within the oral cavity. The expression of 17 genes involved in cell cycle and growth control (p16, p21, p27, p53, cyclin D1, EGFR, c-kit, bcl-6), cell adhesion (alpha-, beta-, and gamma-catenin), and apoptosis/stress response genes (Hif-1-alpha, Glut 1, CA IX, caspase, hsp70, XIAP) were investigated by means of immunohistochemistry. The data were subjected to chi(2), interdependency and Kaplan-Meier analysis. Our study suggests a remote difference in the site-specific gene expression patterns of oral cancer. X-linked inhibitor of apoptosis (XIAP) showed a significantly higher expression (p oral cavity. The increased XIAP expression was further associated with significantly decreased overall survival in all cases of SCCs of the oral cavity (p Expression levels of p53, CA IX, beta-catenin, Hif-1-alpha, and c-kit were also observed to be inversely related between SCCs of the floor of the mouth and those of the tongue respectively, although these differences did not reach statistical significance. Overall and event-free survival did not differ in patients with T1/T2/N0 SCCs according to tumour localization. In summary, the protein expression patterns of SCCs of the oral cavity suggest the existence of a molecular and morphological spectrum of SCCs in the oral cavity. In particular the expression pattern of XIAP indicates distinct gene expression patterns between carcinomas of the floor of the mouth and oral tongue

  14. Oxygen sensing requires mitochondrial ROS but not oxidative phosphorylation.

    Science.gov (United States)

    Brunelle, Joslyn K; Bell, Eric L; Quesada, Nancy M; Vercauteren, Kristel; Tiranti, Valeria; Zeviani, Massimo; Scarpulla, Richard C; Chandel, Navdeep S

    2005-06-01

    Mammalian cells detect decreases in oxygen concentrations to activate a variety of responses that help cells adapt to low oxygen levels (hypoxia). One such response is stabilization of the protein HIF-1 alpha, a component of the transcription factor HIF-1. Here we show that a small interfering RNA (siRNA) against the Rieske iron-sulfur protein of mitochondrial complex III prevents the hypoxic stabilization of HIF-1 alpha protein. Fibroblasts from a patient with Leigh's syndrome, which display residual levels of electron transport activity and are incompetent in oxidative phosphorylation, stabilize HIF-1 alpha during hypoxia. The expression of glutathione peroxidase or catalase, but not superoxide dismutase 1 or 2, prevents the hypoxic stabilization of HIF-1 alpha. These findings provide genetic evidence that oxygen sensing is dependent on mitochondrial-generated reactive oxygen species (ROS) but independent of oxidative phosphorylation.

  15. Self-renewal and pluripotency is maintained in human embryonic stem cells by co-culture with human fetal liver stromal cells expressing hypoxia inducible factor 1alpha.

    Science.gov (United States)

    Ji, Lei; Liu, Yu-xiao; Yang, Chao; Yue, Wen; Shi, Shuang-shuang; Bai, Ci-xian; Xi, Jia-fei; Nan, Xue; Pei, Xue-Tao

    2009-10-01

    Human embryonic stem (hES) cells are typically maintained on mouse embryonic fibroblast (MEF) feeders or with MEF-conditioned medium. However, these xenosupport systems greatly limit the therapeutic applications of hES cells because of the risk of cross-transfer of animal pathogens. The stem cell niche is a unique tissue microenvironment that regulates the self-renewal and differentiation of stem cells. Recent evidence suggests that stem cells are localized in the microenvironment of low oxygen. We hypothesized that hypoxia could maintain the undifferentiated phenotype of embryonic stem cells. We have co-cultured a human embryonic cell line with human fetal liver stromal cells (hFLSCs) feeder cells stably expressing hypoxia-inducible factor-1 alpha (HIF-1alpha), which is known as the key transcription factor in hypoxia. The results suggested HIF-1alpha was critical for preventing differentiation of hES cells in culture. Consistent with this observation, hypoxia upregulated the expression of Nanog and Oct-4, the key factors expressed in undifferentiated stem cells. We further demonstrated that HIF-1alpha could upregulate the expression of some soluble factors including bFGF and SDF-1alpha, which are released into the microenvironment to maintain the undifferentiated status of hES cells. This suggests that the targets of HIF-1alpha are secreted soluble factors rather than a cell-cell contact mechanism, and defines an important mechanism for the inhibition of hESCs differentiation by hypoxia. Our findings developed a transgene feeder co-culture system and will provide a more reliable alternative for future therapeutic applications of hES cells.

  16. The novel hypoxic cytotoxin, TX-2098 has antitumor effect in pancreatic cancer; possible mechanism through inhibiting VEGF and hypoxia inducible factor-1{alpha} targeted gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Miyake, Kotaro, E-mail: hif.panc@gmail.com [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Nishioka, Masanori; Imura, Satoru; Batmunkh, Erdenebulgan [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Uto, Yoshihiro [Department of Biological Science and Technology, Institute of Socio Technosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Nagasawa, Hideko [Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, Gifu 501-1196 (Japan); Hori, Hitoshi [Department of Biological Science and Technology, Institute of Socio Technosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Shimada, Mitsuo [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan)

    2012-08-01

    Tumor hypoxia has been considered to be a potential therapeutic target, because hypoxia is a common feature of solid tumors and is associated with their malignant phenotype. In the present study, we investigated the antitumor effect of a novel hypoxic cytotoxin, 3-[2-hydroxyethyl(methyl)amino]-2-quinoxalinecarbonitrile 1,4-dioxide (TX-2098) in inhibiting the expression of hypoxia inducible factor-1{alpha} (HIF-1{alpha}), and consequently vascular endothelial cell growth factor (VEGF) expression in pancreatic cancer. The antitumor effects of TX-2098 under hypoxia were tested against various human pancreatic cancer cell lines using WST-8 assay. VEGF protein induced pancreatic cancer was determined on cell-free supernatant by ELISA. Moreover, nude mice bearing subcutaneously (s.c.) or orthotopically implanted human SUIT-2 were treated with TX-2098. Tumor volume, survival and expression of HIF-1 and associated molecules were evaluated in treatment versus control groups. In vitro, TX-2098 inhibited the proliferation of various pancreatic cancer cell lines. In s.c model, tumors from nude mice injected with pancreatic cancer cells and treated with TX-2098 showed significant reductions in volume (P < 0.01 versus control). Quantitative real-time reverse transcription-PCR analysis revealed that TX-2098 significantly inhibited mRNA expression of the HIF-1 associated molecules, VEGF, glucose transporter 1 and Aldolase A (P < 0.01 versus control). These treatments also prolong the survival in orthotopic models. These results suggest that the effect of TX-2098 in pancreatic cancer might be correlated with the expression of VEGF and HIF-1 targeted molecules. -- Highlights: Black-Right-Pointing-Pointer We designed and synthesized novel hypoxic cytoxin, TX-2098. Black-Right-Pointing-Pointer TX-2098 inhibited the proliferation of human pancreatic cancer cells than TPZ. Black-Right-Pointing-Pointer TX-2098 reduced VEGF protein level than TPZ. Black-Right-Pointing-Pointer TX-2098

  17. Reversing hypoxic cell chemoresistance in vitro using genetic and small molecule approaches targeting hypoxia inducible factor-1.

    Science.gov (United States)

    Brown, Louisa M; Cowen, Rachel L; Debray, Camille; Eustace, Amanda; Erler, Janine T; Sheppard, Freda C D; Parker, Catriona A; Stratford, Ian J; Williams, Kaye J

    2006-02-01

    The resistance of hypoxic cells to conventional chemotherapy is well documented. Using both adenovirus-mediated gene delivery and small molecules targeting hypoxia-inducible factor-1 (HIF-1), we evaluated the impact of HIF-1 inhibition on the sensitivity of hypoxic tumor cells to etoposide. The genetic therapy exploited a truncated HIF-1alpha protein that acts as a dominant-negative HIF-1alpha (HIF-1alpha-no-TAD). Its functionality was validated in six human tumor cell lines using HIF-1 reporter assays. An EGFP-fused protein demonstrated that the dominant-negative HIF-1alpha was nucleus-localized and constitutively expressed irrespective of oxygen tension. The small molecules studied were quinocarmycin monocitrate (KW2152), its analog 7-cyanoquinocarcinol (DX-52-1), and topotecan. DX-52-1 and topotecan have been previously established as HIF-1 inhibitors. HT1080 and HCT116 cells were treated with either AdHIF-1alpha-no-TAD or nontoxic concentrations (0.1 microM; TAD (multiplicity of infection 50) ablated the anoxic resistance in both cell lines (IC(50) values: HT1080, 0.7 +/- 0.04 microM; HCT116, 3 +/- 1 microM). HIF-1alpha-no-TAD expression inhibited HIF-1-mediated down-regulation of the proapoptotic protein Bid under anoxia. These data support the potential development of HIF-1 targeted approaches in combination with chemotherapy, where hypoxic cell resistance contributes to treatment failure.

  18. Kaempferol inhibits angiogenesis and VEGF expression through both HIF dependent and independent pathways in human ovarian cancer cells.

    Science.gov (United States)

    Luo, Haitao; Rankin, Gary O; Liu, Lingzhi; Daddysman, Matthew K; Jiang, Bing-Hua; Chen, Yi Charlie

    2009-01-01

    Ovarian cancer is 1 of the most significant malignancies in the Western world, and the antiangiogenesis strategy has been postulated for prevention and treatment of ovarian cancers. Kaempferol is a natural flavonoid present in many fruits and vegetables. The antiangiogenesis potential of kaempferol and its underlying mechanisms were investigated in two ovarian cancer cell lines, OVCAR-3 and A2780/CP70. Kaempferol mildly inhibits cell viability but significantly reduces VEGF gene expression at mRNA and protein levels in both ovarian cancer cell lines. In chorioallantoic membranes of chicken embryos, kaempferol significantly inhibits OVCAR-3-induced angiogenesis and tumor growth. HIF-1alpha, a regulator of VEGF, is downregulated by kaempferol treatment in both ovarian cancer cell lines. Kaempferol also represses AKT phosphorylation dose dependently at 5 to 20 muM concentrations. ESRRA is a HIF-independent VEGF regulator, and it is also downregulated by kaempferol in a dose-dependent manner. Overall, this study demonstrated that kaempferol is low in cytotoxicity but inhibits angiogenesis and VEGF expression in human ovarian cancer cells through both HIF-dependent (Akt/HIF) and HIF-independent (ESRRA) pathways and deserves further studies for possible application in angio prevention and treatment of ovarian cancers.

  19. Analysis of the early adaptive response of endothelial cells to hypoxia via a long serial analysis of gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Guang-Ping; Su, Yong-Yue; Chen, Jian; Yang, Zong-Cheng [State Key Laboratory of Trauma, Burn and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Liu, You-Sheng [Institute of Pathology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Luo, Xiang-Dong, E-mail: luoxd2005@163.com [State Key Laboratory of Trauma, Burn and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China)

    2009-07-10

    Activation of endothelial cells in humans is an early event in the response to hypoxia that may contribute to the endothelium's endogenous capacity to reduce tissue injury. To better understand the mechanism underlying this process, we utilized Long Serial Analysis of Gene Expression to study the transcriptome of human vein umbilical endothelial cells (EA.hy926) shortly after the induction of hypoxia. Of over 13,000 genes detected in each pool, 112 showed obvious differences in expression. Metabolic processes such as protein biosynthesis and proteolysis, aminoglycan metabolism, ribonucleotide biosynthesis, adenosine salvage, and lipid metabolism were reinforced. Pro-proliferation and pro-apoptotic states suggest the co-existence of pro- and anti-injury forces in endothelium shortly after the induction of hypoxia. Other adaptive responses include reinforced angiogenesis and vasodilation. Additionally, gene transcription in the endothelium shortly after the induction of hypoxia was regulated independently of HIF-1{alpha}. Our efforts to elucidate the adaptive response at an early post-hypoxia stage should contribute to further investigation of the protective processes that occur in the endothelium and has potential clinical implications.

  20. The potential role of Brachyury in inducing epithelial-to-mesenchymal transition (EMT) and HIF-1α expression in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Chao [Department of Mammary Surgery, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, 528403 (China); Zhang, Jingjing, E-mail: jingjingzhangzs@163.com [Department of Cancer Radiotherapy, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, 528403 (China); Fu, Jianhua [Department of Thoracic Surgery, Cancer Center, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, 528403 (China); Ling, Feihai, E-mail: feihailingfhl@163.com [Department of Mammary Surgery, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, 528403 (China)

    2015-11-27

    One of transcription factors of the T-box family, Brachyury has been implicated in tumorigenesis of many types of cancers, regulating cancer cell proliferation, metastasis, invasion and epithelial-to-mesenchymal transition (EMT). However, the role of Brachyury in breast cancer cells has been scarcely reported. The present study aimed to investigate the expression and role of Brachyury in breast cancer. Brachyury expression was analyzed by qRT-PCR and Western blot. The correlations between Brachyury expression and clinicopathological factors of breast cancer were determined. Involvement of EMT stimulation and hypoxia-inducible factor-1α (HIF-1α) expression induction by Brachyury was also evaluated. Moreover, the effect of Brachyury on tumor growth and metastasis in vivo was examined in a breast tumor xenograft model. Brachyury expression was enhanced in primary breast cancer tissues and Brachyury expression was correlated with tumor stage and lymph node metastasis. Hypoxia enhanced Brachyury expression, the silencing of which blocked the modulation effect of hypoxia on E-cadherin and vimentin expression. Brachyury significantly augmented HIF-1alpha expression via PTEN/Akt signaling as well as accelerated cell proliferation and migration in vitro. Additionally, Brachyury accelerated breast tumor xenograft growth and increased lung metastasis in nude mice. In summary, our data confirmed that Brachyury might contribute to hypoxia-induced EMT of breast cancer and trigger HIF-1alpha expression via PTEN/Akt signaling. - Highlights: • Brachyury expression was correlated with tumor stage and lymph node metastasis. • Hypoxia enhanced Brachyury expression, which contributes to hypoxia-induced EMT. • Brachyury significantly augmented HIF-1alpha expression via PTEN/Akt signaling. • Brachyury accelerated tumor xenograft growth and increased lung metastasis.

  1. Recombinant protein expression in Nicotiana.

    Science.gov (United States)

    Matoba, Nobuyuki; Davis, Keith R; Palmer, Kenneth E

    2011-01-01

    Recombinant protein pharmaceuticals are now widely used in treatment of chronic diseases, and several recombinant protein subunit vaccines are approved for human and veterinary use. With growing demand for complex protein pharmaceuticals, such as monoclonal antibodies, manufacturing capacity is becoming limited. There is increasing need for safe, scalable, and economical alternatives to mammalian cell culture-based manufacturing systems, which require substantial capital investment for new manufacturing facilities. Since a seminal paper reporting immunoglobulin expression in transgenic plants was published in 1989, there have been many technological advances in plant expression systems to the present time where production of proteins in leaf tissues of nonfood crops such as Nicotiana species is considered a viable alternative. In particular, transient expression systems derived from recombinant plant viral vectors offer opportunities for rapid expression screening, construct optimization, and expression scale-up. Extraction of recombinant proteins from Nicotiana leaf tissues can be achieved by collection of secreted protein fractions, or from a total protein extract after grinding the leaves with buffer. After separation from solids, the major purification challenge is contamination with elements of the photosynthetic complex, which can be solved by application of a variety of facile and proven strategies. In conclusion, the technologies required for safe, efficient, scalable manufacture of recombinant proteins in Nicotiana leaf tissues have matured to the point where several products have already been tested in phase I clinical trials and will soon be followed by a rich pipeline of recombinant vaccines, microbicides, and therapeutic proteins.

  2. VEGF gene expression in adult human thymus fat: a correlative study with hypoxic induced factor and cyclooxygenase-2.

    Directory of Open Access Journals (Sweden)

    Francisco Tinahones

    Full Text Available UNLABELLED: It is well known that the adult human thymus degenerates into fat tissue; however, it has never been considered as a potential source of angiogenic factors. Recently, we have described that this fat (TAT produces angiogenic factors and induces human endothelial cell proliferation and migration, indicating its potential angiogenic properties. DESIGN: Adult thymus fat and subcutaneous adipose tissue specimens were obtained from 28 patients undergoing cardiac surgery, making this tissue readily available as a prime source of adipose tissue. We focused our investigation on determining VEGF gene expression and characterizing the different genes, mediators of inflammation and adipogenesis, and which are known to play a relevant role in angiogenesis regulation. RESULTS: We found that VEGF-A was the isoform most expressed in TAT. This expression was accompanied by an upregulation of HIF-1alpha, COX-2 and HO-1 proteins, and by increased HIF-1 DNA binding activity, compared to SAT. Furthermore, we observed that TAT contains a high percentage of mature adipocytes, 0.25% of macrophage cells, 15% of endothelial cells and a very low percentage of thymocyte cells, suggesting the cellular variability of TAT, which could explain the differences in gene expression observed in TAT. Subsequently, we showed that the expression of genes known as adipogenic mediators, including PPARgamma1/gamma2, FABP-4 and adiponectin was similar in both TAT and SAT. Moreover the expression of these latter genes presented a significantly positive correlation with VEGF, suggesting the potential association between VEGF and the generation of adipose tissue in adult thymus. CONCLUSION: Here we suggest that this fat has a potential angiogenic function related to ongoing adipogenesis, which substitutes immune functions within the adult thymus. The expression of VEGF seems to be associated with COX-2, HO-1 and adipogenesis related genes, suggesting the importance that this new

  3. Protein kinase CK2 inhibition is associated with the destabilization of HIF-1α in human cancer cells

    DEFF Research Database (Denmark)

    Guerra, Barbara; Rasmussen, Tine D. L.; Schnitzler, Alexander

    2015-01-01

    Screening for protein kinase CK2 inhibitors of the structural diversity compound library (DTP NCI/NIH) led to the discovery of 4-[(E)-(fluoren-9-ylidenehydrazinylidene)-methyl]benzoic acid (E9). E9 induces apoptotic cell death in various cancer cell lines and upon hypoxia, the compound suppresses...... CK2-catalyzed HSP90/Cdc37 phosphorylation and induces HIF-1alpha degradation. Furthermore, E9 exerts a strong anti-tumour activity by inducing necrosis in murine xenograft models underlining its potential to be used for cancer treatment in future clinical studies. Crystal structure analysis of human...

  4. [Cell apoptosis and expression of hypoxia-inducible transcription factor-1 alpha in kidney tissue after severe burn with delayed fluid resuscitation in rats in areas of different altitude].

    Science.gov (United States)

    Jiang, Jiang; Liu, Yi; Zhang, Shi-fan; Cai, Qian; Zhang, Xian-ying; Zhang, Bin; Xiao, Bin

    2008-07-01

    To explore the relationship of cell apoptosis and expression regularity of hypoxia-inducible transcription factor (HIF)-1 alpha after severe burn with delayed fluid resuscitation in areas of different altitude. A total of 240 male Wistar rats, which were raised in areas of different altitude (1,517 and 3,840 meters), were employed as the experimental models [They received a 30% total body surface area (TBSA)III degree scald injury], and then they were randomly divided into 3 groups: delayed fluid resuscitation group (DFR, n=50), immediate fluid resuscitation group (IFR, n=60) and control group (CG, n=10). Renal tissue samples were harvested at 1, 6, 12, 24, 72 and 168 hours after burn, respectively. Cell apoptosis was detected by tissue chip technology and terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling (TUNEL). The expression of HIF-1 alpha was assessed by immunohistochemistry and image analysis. With increase in altitude, cellular edema, degeneration, necrosis and disintegration of renal tissue were gradually worsening, the capillaries of renal glomeruli became dilated and engorged, with degeneration and necrosis of endothelial cells, engorgement and edema of renal interstitium, and infiltration of inflammatory cells. Pathological changes in DFR group were more serious than that of IFR group. Cell apoptosis and the expression of HIF-1 alpha were both enhanced, the latter mainly appeared in nuclei of renal cells, and they were more marked at 3,840 meters compared with those at 1,517 meters. They were more marked in experimental groups than in control group, especially so in DFR group (Pkidney cell apoptosis.

  5. Effect of a HIF-1 Alpha Polymorphism on the Incidence and Prostate Cancer

    Science.gov (United States)

    2007-02-01

    factor levels and risk of prostate cancer. Cancer Epidemiol Biomarkers Prev 2005;14(6):1557-1561. 34. Percy MJ, Mooney SM, McMullin MF, Flores A...vascular endothelial growth factor in pathological angiogenesis. Breast Cancer Research & Treatment 1995;36(2):127-137. 37. Jackson MW, Bentel JM, Tilley

  6. Effect of a HIF-1 Alpha Polymorphism on the Incidence and Prostate Cancer

    Science.gov (United States)

    2008-02-01

    system (Dynex Technologies, Chantilly, VA) and a human VEGF immunoassay Quantiglo kit (R&D Systems, Minneapolis, MN). The median CV for the quality...Oncol 2004;22(15):3104–3112. 30. Harman SM, Metter EJ, Blackman MR, Landis PK, Carter HB . Serum levels of insulin-like growth factor I (IGF-I), IGF-II

  7. Development of a Combination Therapy for Prostate Cancer by Targeting Stat3 and HIF-1alpha

    Science.gov (United States)

    2013-07-01

    USA. Although localized disease is often curable, advanced disease is generally not, especially when the cancer becomes castration resistant (mCRPC...for 4h. Cooling the mixture to Fig.B1. NDT extracted from Z.nitidum Fig.B2a. TEL03 is a derivative of perylence, which is origenal derived from

  8. Host - HIF- 1alpha Pathway And Hypoxia: In Vitro Studies And Mathematical Model

    Science.gov (United States)

    2016-08-30

    collected and counted using trypan blue (Invitrogen, part of ThermoFisher Scientific) on a Countess automated cell counter (Invitrogen). 3.1.2...Santa Cruz Biotechnology , Dallas TX) diluted 1:250 in blocking buffer for 1 hour at 37°C. Cells were washed twice with PBS. Cells were incubated in...blocking buffer containing secondary antibody diluted 1:250 (SC-2010, Santa Cruz Biotechnology ) and 1 µL/mL Hoechst® 33342 dye (ThermoFisher

  9. HIF-1alpha and NOTCH signaling in ductal and lobular carcinomas of the breast

    NARCIS (Netherlands)

    Ercan, C.; Vermeulen, J.F.; Hoefnagel, L.; Bult, P.; Groep, P. van der; Wall, E. van der; Diest, P.J. van

    2012-01-01

    BACKGROUND: NOTCH signaling is involved in every step of metazoan development and maintenance of adult tissue homeostasis. It is frequently deregulated by mutations and overexpression in different cancer types including solid tumors such as breast cancer. Another common feature of solid tumors is hy

  10. Development of a Combination Therapy for Prostate Cancer by Targeting Stat3 and HIF-1alpha

    Science.gov (United States)

    2011-07-01

    isolated several novel molecules from Chinese herbal medicines. After activity tests of these molecules, we found one compound, TEL, that is a...research plan with three aims to expand these efforts. (1) To isolate and synthesize additional novel compounds from Chinese herbal medicines for...mg) was resolved in 10%SDS–PAGE gels , transferred to Hybond-ECL nitrocellulose membrane, blocked with 5% non-fat skim milk, and probed with specific

  11. HIF-1[alpha] effects on angiogenic potential in human small cell lung carcinoma

    National Research Council Canada - National Science Library

    Wan, Jun; Chai, Huiping; Yu, Zaicheng; Ge, Wei; Kang, Ningning; Xia, Wanli; Che, Yun

    2011-01-01

    ...] in vitro and in vivo. In vivo we used an alternative method to study the effect of HIF-1a on angiogenic potential of SCLC by buliding NCI-H446 cell transplantation tumor on the chick embryo chorioallantoic membrane (CAM) surface...

  12. ATF-1 is a hypoxia-responsive transcriptional activator of skeletal muscle mitochondrial-uncoupling protein 3.

    Science.gov (United States)

    Lu, Zhongping; Sack, Michael N

    2008-08-22

    Hypoxia induces oxidative damage in skeletal muscle. Uncoupling protein 3 (UCP3) is the skeletal muscle enriched uncoupling protein and has previously been shown to confer resistance against oxidative stress. We show that hypoxia robustly up-regulates skeletal muscle UCP3 and that the absence of UCP3 in primary skeletal myocytes exacerbates hypoxia-induced reactive oxygen species generation. In this context, we reasoned that the investigation of the regulation of UCP3 may identify novel hypoxia-responsive regulatory pathways that modulate intrinsic anti-oxidant defenses. By screening a transcription factor array of 704 full-length cDNAs in murine C2C12 myoblasts following cotransfection of a murine UCP3 promoter-luciferase construct and myoD we identified numerous candidate regulatory factors that up-regulate UCP3. Active transcription factor-1 (ATF-1) was identified, and as this transcription factor is a known component of a multiprotein hypoxia-induced regulatory complex, we explored its role in hypoxia-mediated UCP3 up-regulation. Site-directed mutagenesis and chromatin immunoprecipitation assays identify a 10-bp region required for ATF-1 induction of UCP3 promoter activity. Hypoxia promotes the phosphorylation of ATF-1, and the knockdown of ATF-1 by shRNA prevents hypoxia-mediated up-regulation of UCP3. Pharmacologic inhibition of p38 MAP kinase prevents both hypoxia-mediated ATF-1 phosphorylation and UCP3 up-regulation. PKA signaling does not modulate hypoxia-induced UCP3 up-regulation and neither does HIF-1alpha activation by cobalt chloride. In conclusion, ATF-1, via p38 MAP kinase activation, functions as a novel regulatory pathway driving UCP3 expression. These data reinforce the role of ATF-1 as a hypoxia-responsive trans-activator and identifies a novel regulatory program that may modulate cellular responses to oxygen-deficit.

  13. Predictable tuning of protein expression in bacteria

    DEFF Research Database (Denmark)

    Bonde, Mads; Pedersen, Margit; Klausen, Michael Schantz

    2016-01-01

    We comprehensively assessed the contribution of the Shine-Dalgarno sequence to protein expression and used the data to develop EMOPEC (Empirical Model and Oligos for Protein Expression Changes; http://emopec.biosustain.dtu.dk). EMOPEC is a free tool that makes it possible to modulate the expressi...

  14. Coevolution of gene expression among interacting proteins

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, Hunter B.; Hirsh, Aaron E.; Wall, Dennis P.; Eisen,Michael B.

    2004-03-01

    Physically interacting proteins or parts of proteins are expected to evolve in a coordinated manner that preserves proper interactions. Such coevolution at the amino acid-sequence level is well documented and has been used to predict interacting proteins, domains, and amino acids. Interacting proteins are also often precisely coexpressed with one another, presumably to maintain proper stoichiometry among interacting components. Here, we show that the expression levels of physically interacting proteins coevolve. We estimate average expression levels of genes from four closely related fungi of the genus Saccharomyces using the codon adaptation index and show that expression levels of interacting proteins exhibit coordinated changes in these different species. We find that this coevolution of expression is a more powerful predictor of physical interaction than is coevolution of amino acid sequence. These results demonstrate previously uncharacterized coevolution of gene expression, adding a different dimension to the study of the coevolution of interacting proteins and underscoring the importance of maintaining coexpression of interacting proteins over evolutionary time. Our results also suggest that expression coevolution can be used for computational prediction of protein protein interactions.

  15. Coevolution of gene expression among interacting proteins

    OpenAIRE

    2004-01-01

    Physically interacting proteins or parts of proteins are expected to evolve in a coordinated manner that preserves proper interactions. Such coevolution at the amino acid-sequence level is well documented and has been used to predict interacting proteins, domains, and amino acids. Interacting proteins are also often precisely coexpressed with one another, presumably to maintain proper stoichiometry among interacting components. Here, we show that the expression levels of physically inter...

  16. TRPM4 protein expression in prostate cancer

    DEFF Research Database (Denmark)

    Berg, Kasper Drimer; Soldini, Davide; Jung, Maria;

    2016-01-01

    BACKGROUND: Transient receptor potential cation channel, subfamily M, member 4 (TRPM4) messenger RNA (mRNA) has been shown to be upregulated in prostate cancer (PCa) and might be a new promising tissue biomarker. We evaluated TRPM4 protein expression and correlated the expression level with bioch......BACKGROUND: Transient receptor potential cation channel, subfamily M, member 4 (TRPM4) messenger RNA (mRNA) has been shown to be upregulated in prostate cancer (PCa) and might be a new promising tissue biomarker. We evaluated TRPM4 protein expression and correlated the expression level.......79-2.62; p = 0.01-0.03 for the two observers) when compared to patients with a lower staining intensity. CONCLUSIONS: TRPM4 protein expression is widely expressed in benign and cancerous prostate tissue, with highest staining intensities found in PCa. Overexpression of TRPM4 in PCa (combination of high...

  17. Reversing hypoxic cell chemoresistance in vitro using genetic and small molecule approaches targeting hypoxia inducible factor-1

    DEFF Research Database (Denmark)

    Brown, Louisa M; Cowen, Rachel L; Debray, Camille;

    2006-01-01

    . The genetic therapy exploited a truncated HIF-1alpha protein that acts as a dominant-negative HIF-1alpha (HIF-1alpha-no-TAD). Its functionality was validated in six human tumor cell lines using HIF-1 reporter assays. An EGFP-fused protein demonstrated that the dominant-negative HIF-1alpha was nucleus......HIF-1alpha-no-TAD or nontoxic concentrations (0.1 microM; ... higher than those in air for HT1080 (2.2 +/- 0.3 versus 0.7 +/- 0.2 microM) and HCT116 (9 +/- 4 versus 3 +/- 2 microM) cells. KW2152 and DX-52-1 significantly reduced the anoxic etoposide IC(50) in HT1080 cells, whereas only KW2152 yielded sensitization in HCT116 cells. In contrast, AdHIF-1alpha-no-TAD...

  18. ABL Tyrosine Kinase Stimulates PUMA Protein Expression

    OpenAIRE

    Oon, Chet K

    2016-01-01

    ABL is an ubiquitously expressed non-receptor tyrosine kinase involved in multiple cellular functions including programmed cell death. Upon DNA damage, ABL has been shown to upregulate PUMA, p53 upregulated modulator of apoptosis, and causes downstream mitochondrial intrinsic apoptotic events. However, the mechanism by which ABL regulates PUMA expression remains unknown. We have shown that ABL does not change PUMA protein subcellular localization through immunofluorescence. Through protein an...

  19. Catechol-o-methyltransferase expression and 2-methoxyestradiol affect microtubule dynamics and modify steroid receptor signaling in leiomyoma cells.

    Directory of Open Access Journals (Sweden)

    Salama A Salama

    Full Text Available CONTEXT: Development of optimal medicinal treatments of uterine leiomyomas represents a significant challenge. 2-Methoxyestradiol (2ME is an endogenous estrogen metabolite formed by sequential action of CYP450s and catechol-O-methyltransferase (COMT. Our previous study demonstrated that 2ME is a potent antiproliferative, proapoptotic, antiangiogenic, and collagen synthesis inhibitor in human leiomyomas cells (huLM. OBJECTIVES: Our objectives were to investigate whether COMT expression, by the virtue of 2ME formation, affects the growth of huLM, and to explore the cellular and molecular mechanisms whereby COMT expression or treatment with 2ME affect these cells. RESULTS: Our data demonstrated that E(2-induced proliferation was less pronounced in cells over-expressing COMT or treated with 2ME (500 nM. This effect on cell proliferation was associated with microtubules stabilization and diminution of estrogen receptor alpha (ERalpha and progesterone receptor (PR transcriptional activities, due to shifts in their subcellular localization and sequestration in the cytoplasm. In addition, COMT over expression or treatment with 2ME reduced the expression of hypoxia-inducible factor -1alpha (HIF-1 alpha and the basal level as well as TNF-alpha-induced aromatase (CYP19 expression. CONCLUSIONS: COMT over expression or treatment with 2ME stabilize microtubules, ameliorates E(2-induced proliferation, inhibits ERalpha and PR signaling, and reduces HIF-1 alpha and CYP19 expression in human uterine leiomyoma cells. Thus, microtubules are a candidate target for treatment of uterine leiomyomas. In addition, the naturally occurring microtubule-targeting agent 2ME represents a potential new therapeutic for uterine leiomyomas.

  20. Analysis of correlations between protein complex and protein-protein interaction and mRNA expression

    Institute of Scientific and Technical Information of China (English)

    CAI Lun; XUE Hong; LU Hongchao; ZHAO Yi; ZHU Xiaopeng; BU Dongbo; LING Lunjiang; CHEN Runsheng

    2003-01-01

    Protein-protein interaction is a physical interaction of two proteins in living cells. In budding yeast Saccharomyces cerevisiae, large-scale protein-protein interaction data have been obtained through high-throughput yeast two-hybrid systems (Y2H) and protein complex purification techniques based on mass-spectrometry. Here, we collect 11855 interactions between total 2617 proteins. Through seriate genome-wide mRNA expression data, similarity between two genes could be measured. Protein complex data can also be obtained publicly and can be translated to pair relationship that any two proteins can only exist in the same complex or not. Analysis of protein complex data, protein-protein interaction data and mRNA expression data can elucidate correlations between them. The results show that proteins that have interactions or similar expression patterns have a higher possibility to be in the same protein complex than randomized selected proteins, and proteins which have interactions and similar expression patterns are even more possible to exist in the same protein complex. The work indicates that comprehensive integration and analysis of public large-scale bioinformatical data, such as protein complex data, protein-protein interaction data and mRNA expression data, may help to uncover their relationships and common biological information underlying these data. The strategies described here may help to integrate and analyze other functional genomic and proteomic data, such as gene expression profiling, protein-localization mapping and large-scale phenotypic data, both in yeast and in other organisms.

  1. Integral Membrane Protein Expression in Saccharomyces cerevisiae.

    Science.gov (United States)

    Boswell-Casteel, Rebba C; Johnson, Jennifer M; Stroud, Robert M; Hays, Franklin A

    2016-01-01

    Eukaryotic integral membrane proteins are challenging targets for crystallography or functional characterization in a purified state. Since expression is often a limiting factor when studying this difficult class of biological macromolecules, the intent of this chapter is to focus on the expression of eukaryotic integral membrane proteins (IMPs) using the model organism Saccharomyces cerevisiae. S. cerevisiae is a prime candidate for the expression of eukaryotic IMPs because it offers the convenience of using episomal expression plasmids, selection of positive transformants, posttranslational modifications, and it can properly fold and target IMPs. Here we present a generalized protocol and insights based on our collective knowledge as an aid to overcoming the challenges faced when expressing eukaryotic IMPs in S. cerevisiae.

  2. Biotechnology Protein Expression and Purification Facility

    Science.gov (United States)

    2003-01-01

    The purpose of the Project Scientist Core Facility is to provide purified proteins, both recombinant and natural, to the Biotechnology Science Team Project Scientists and the NRA-Structural Biology Test Investigators. Having a core facility for this purpose obviates the need for each scientist to develop the necessary expertise and equipment for molecular biology, protein expression, and protein purification. Because of this, they are able to focus their energies as well as their funding on the crystallization and structure determination of their target proteins.

  3. Differentially expressed proteins on postoperative 3

    Directory of Open Access Journals (Sweden)

    Jialili Ainuer

    2011-04-01

    Full Text Available 【Abstract】Objectives: Surgical repair of Achilles tendon (AT rupture should immediately be followed by active tendon mobilization. The optimal time as to when the mobilization should begin is important yet controversial. Early kinesitherapy leads to reduced rehabilitation period. However, an insight into the detailed mechanism of this process has not been gained. Proteomic technique can be used to separate and purify the proteins by differential expression profile which is related to the function of different proteins, but research in the area of proteomic analysis of AT 3 days after repair has not been studied so far. Methods: Forty-seven New Zealand white rabbits were randomized into 3 groups. Group A (immobilization group, n=16 received postoperative cast immobilization; Group B (early motion group, n=16 received early active motion treatments immediately following the repair of AT rupture from tenotomy. Another 15 rabbits served as control group (Group C. The AT samples were prepared 3 days following the microsurgery. The proteins were separated employing twodimensional polyacrylamide gel electrophoresis (2D-PAGE. PDQuest software version 8.0 was used to identify differentially expressed proteins, followed by peptide mass fingerprint (PMF and tandem mass spectrum analysis, using the National Center for Biotechnology Information (NCBI protein database retrieval and then for bioinformatics analysis. Results: A mean of 446.33, 436.33 and 462.67 protein spots on Achilles tendon samples of 13 rabbits in Group A, 14 rabbits in Group B and 13 rabbits in Group C were successfully detected in the 2D-PAGE. There were 40, 36 and 79 unique proteins in Groups A, B and C respectively. Some differentially expressed proteins were enzyme with the gel, matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS. We successfully identified 9 and 11 different proteins in Groups A and B, such as GAPDH, phosphoglycerate kinase 1

  4. Designing genes for successful protein expression.

    Science.gov (United States)

    Welch, Mark; Villalobos, Alan; Gustafsson, Claes; Minshull, Jeremy

    2011-01-01

    DNA sequences are now far more readily available in silico than as physical DNA. De novo gene synthesis is an increasingly cost-effective method for building genetic constructs, and effectively removes the constraint of basing constructs on extant sequences. This allows scientists and engineers to experimentally test their hypotheses relating sequence to function. Molecular biologists, and now synthetic biologists, are characterizing and cataloging genetic elements with specific functions, aiming to combine them to perform complex functions. However, the most common purpose of synthetic genes is for the expression of an encoded protein. The huge number of different proteins makes it impossible to characterize and catalog each functional gene. Instead, it is necessary to abstract design principles from experimental data: data that can be generated by making predictions followed by synthesizing sequences to test those predictions. Because of the degeneracy of the genetic code, design of gene sequences to encode proteins is a high-dimensional problem, so there is no single simple formula to guarantee success. Nevertheless, there are several straightforward steps that can be taken to greatly increase the probability that a designed sequence will result in expression of the encoded protein. In this chapter, we discuss gene sequence parameters that are important for protein expression. We also describe algorithms for optimizing these parameters, and troubleshooting procedures that can be helpful when initial attempts fail. Finally, we show how many of these methods can be accomplished using the synthetic biology software tool Gene Designer.

  5. Streamlined expressed protein ligation using split inteins.

    Science.gov (United States)

    Vila-Perelló, Miquel; Liu, Zhihua; Shah, Neel H; Willis, John A; Idoyaga, Juliana; Muir, Tom W

    2013-01-09

    Chemically modified proteins are invaluable tools for studying the molecular details of biological processes, and they also hold great potential as new therapeutic agents. Several methods have been developed for the site-specific modification of proteins, one of the most widely used being expressed protein ligation (EPL) in which a recombinant α-thioester is ligated to an N-terminal Cys-containing peptide. Despite the widespread use of EPL, the generation and isolation of the required recombinant protein α-thioesters remain challenging. We describe here a new method for the preparation and purification of recombinant protein α-thioesters using engineered versions of naturally split DnaE inteins. This family of autoprocessing enzymes is closely related to the inteins currently used for protein α-thioester generation, but they feature faster kinetics and are split into two inactive polypeptides that need to associate to become active. Taking advantage of the strong affinity between the two split intein fragments, we devised a streamlined procedure for the purification and generation of protein α-thioesters from cell lysates and applied this strategy for the semisynthesis of a variety of proteins including an acetylated histone and a site-specifically modified monoclonal antibody.

  6. Engineering genes for predictable protein expression.

    Science.gov (United States)

    Gustafsson, Claes; Minshull, Jeremy; Govindarajan, Sridhar; Ness, Jon; Villalobos, Alan; Welch, Mark

    2012-05-01

    The DNA sequence used to encode a polypeptide can have dramatic effects on its expression. Lack of readily available tools has until recently inhibited meaningful experimental investigation of this phenomenon. Advances in synthetic biology and the application of modern engineering approaches now provide the tools for systematic analysis of the sequence variables affecting heterologous expression of recombinant proteins. We here discuss how these new tools are being applied and how they circumvent the constraints of previous approaches, highlighting some of the surprising and promising results emerging from the developing field of gene engineering.

  7. Hypoxia determines survival outcomes of bacterial infection through HIF-1alpha dependent re-programming of leukocyte metabolism *

    Science.gov (United States)

    Thompson, A.A.R.; Dickinson, R.S.; Murphy, F.; Thomson, J. P.; Marriott, H.M.; Tavares, A.; Willson, J.; Williams, L.; Lewis, A.; Mirchandani, A.; Dos Santos Coelho, P.; Doherty, C.; Ryan, E.; Watts, E.; Morton, N. M.; Forbes, S.; Stimson, R. H.; Hameed, A. G.; Arnold, N.; Preston, J.A.; Lawrie, A.; Finisguerra, V.; Mazzone, M.; Sadiku, P.; Goveia, J.; Taverna, F.; Carmeliet, P.; Foster, S.J.; Chilvers, E.R.; Cowburn, A.S.; Dockrell, D.H.; Johnson, R.S.; Meehan, R. R.; Whyte, M.K.B.; Walmsley, S.R.

    2017-01-01

    Hypoxia and bacterial infection frequently co-exist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both S. aureus and S. pneumoniae infections rapidly induced progressive neutrophil mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning animals through longer exposures to hypoxia, prior to infection, prevented these pathophysiological responses and profoundly dampened the transcriptome of circulating leukocytes. Specifically, perturbation of HIF pathway and glycolysis genes by hypoxic preconditioning was associated with reduced leukocyte glucose utilisation, resulting in systemic rescue from a global negative energy state and myocardial protection. Thus we demonstrate that hypoxia preconditions the innate immune response and determines survival outcomes following bacterial infection through suppression of HIF-1α and neutrophil metabolism. The therapeutic implications of this work are that in the context of systemic or tissue hypoxia therapies that target the host response could improve infection associated morbidity and mortality. PMID:28386604

  8. Administration of follicle-stimulating hormone induces autophagy via upregulation of HIF-1[alpha] in mouse granulosa cells

    National Research Council Canada - National Science Library

    Jilong Zhou; Wang Yao; Chengyu Li; Wangjun Wu; Qifa Li; Honglin Liu

    2017-01-01

    ...) on mouse granulosa cells (MGCs). Results indicated that autophagy was induced by FSH, which is known to be the dominant hormone regulating follicular development and granulosa cell (GC) proliferation...

  9. Hypoxia determines survival outcomes of bacterial infection through HIF-1alpha dependent re-programming of leukocyte metabolism.

    Science.gov (United States)

    Thompson, A A R; Dickinson, R S; Murphy, F; Thomson, J P; Marriott, H M; Tavares, A; Willson, J; Williams, L; Lewis, A; Mirchandani, A; Dos Santos Coelho, P; Doherty, C; Ryan, E; Watts, E; Morton, N M; Forbes, S; Stimson, R H; Hameed, A G; Arnold, N; Preston, J A; Lawrie, A; Finisguerra, V; Mazzone, M; Sadiku, P; Goveia, J; Taverna, F; Carmeliet, P; Foster, S J; Chilvers, E R; Cowburn, A S; Dockrell, D H; Johnson, R S; Meehan, R R; Whyte, M K B; Walmsley, S R

    2017-02-10

    Hypoxia and bacterial infection frequently co-exist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both S. aureus and S. pneumoniae infections rapidly induced progressive neutrophil mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning animals through longer exposures to hypoxia, prior to infection, prevented these pathophysiological responses and profoundly dampened the transcriptome of circulating leukocytes. Specifically, perturbation of HIF pathway and glycolysis genes by hypoxic preconditioning was associated with reduced leukocyte glucose utilisation, resulting in systemic rescue from a global negative energy state and myocardial protection. Thus we demonstrate that hypoxia preconditions the innate immune response and determines survival outcomes following bacterial infection through suppression of HIF-1α and neutrophil metabolism. The therapeutic implications of this work are that in the context of systemic or tissue hypoxia therapies that target the host response could improve infection associated morbidity and mortality.

  10. The role of selective Cox-2 inhibitors on HIF-1 alpha gene in colorectal cancer: an in-vitro study

    Directory of Open Access Journals (Sweden)

    Sanaz Rismanchi

    2014-10-01

    Conclusion: Angiogenesis is a key factor in the carcinogenesis process and FDA today approved bevacizumab as a first-line treatment for patients with metastatic colorectal cancer. The results of this study showed one of the causes of angiogenesis reduction in celecoxib-treated colorectal cancer. According to clinical findings and basic studies, celecoxib will be hopefully used as a first-line therapy along with chemotherapy in the near future in colorectal cancer. The advantages of this treatment method include its low cost and low side effects.

  11. Relative Contribution of Prolyl Hydroxylase-Dependent and -Independent Degradation of HIF-1alpha by Proteasomal Pathways in Cerebral Ischemia

    Directory of Open Access Journals (Sweden)

    Yomna Badawi

    2017-05-01

    Full Text Available Hypoxia inducible factor-1 (HIF-1 is a key regulator in hypoxia and can determine the fate of brain cells during ischemia. However, the mechanism of HIF-1 regulation is still not fully understood in ischemic brains. We tested a hypothesis that both the 26S and the 20S proteasomal pathways were involved in HIF-1α degradation under ischemic conditions. Using in vitro ischemic model (oxygen and glucose deprivation and a mouse model of middle cerebral artery occlusion, we tested effects of inhibitors of proteasomes and prolyl hydroxylase (PHD on HIF-1α stability and brain injury in cerebral ischemia. We observed that 30 and 60 min of oxygen-glucose deprivation significantly increased the 20S proteasomal activity. We demonstrated that proteasome inhibitors increased HIF-1α stabilization and cell viability and were more effective than PHD inhibitors in primary cultured cortical neurons exposed to oxygen and glucose deprivation. Furthermore, the administration of the proteasome inhibitor, epoxomicin, to mice resulted in smaller infarct size and brain edema than a PHD inhibitor. Our results indicate that 20S proteasomes are involved in HIF-1α degradation in ischemic neurons and that proteasomal inhibition provides more HIF-1α stabilization and neuroprotection than PHD inhibition in cerebral ischemia.

  12. mTOR- and HIF-1 alpha-mediated aerobic glycolysis as metabolic basis for trained immunity

    NARCIS (Netherlands)

    Cheng, Shih-Chin; Quintin, Jessica; Cramer, Robert A.; Shepardson, Kelly M.; Saeed, Sadia; Kumar, Vinod; Giamarellos-Bourboulis, Evangelos J.; Martens, Joost H. A.; Rao, Nagesha Appukudige; Aghajanirefah, Ali; Manjeri, Ganesh R.; Li, Yang; Ifrim, Daniela C.; Arts, Rob J. W.; van der Meer, Brian M. J. W.; Deen, Peter M. T.; Logie, Colin; O'Neill, Luke A.; Willems, Peter; van de Veerdonk, Frank L.; van der Meer, Jos W. M.; Ng, Aylwin; Joosten, Leo A. B.; Wijmenga, Cisca; Stunnenberg, Hendrik G.; Xavier, Ramnik J.; Netea, Mihai G.

    2014-01-01

    Epigenetic reprogramming of myeloid cells, also known as trained immunity, confers nonspecific protection from secondary infections. Using histone modification profiles of human monocytes trained with the Candida albicans cell wall constituent beta-glucan, together with a genome-wide transcriptome,

  13. Expression Differentiation Is Constrained to Low-Expression Proteins over Ecological Timescales.

    Science.gov (United States)

    Margres, Mark J; Wray, Kenneth P; Seavy, Margaret; McGivern, James J; Herrera, Nathanael D; Rokyta, Darin R

    2016-01-01

    Protein expression level is one of the strongest predictors of protein sequence evolutionary rate, with high-expression protein sequences evolving at slower rates than low-expression protein sequences largely because of constraints on protein folding and function. Expression evolutionary rates also have been shown to be negatively correlated with expression level across human and mouse orthologs over relatively long divergence times (i.e., ∼100 million years). Long-term evolutionary patterns, however, often cannot be extrapolated to microevolutionary processes (and vice versa), and whether this relationship holds for traits evolving under directional selection within a single species over ecological timescales (i.e., protein is predicted to be a tradeoff between the benefit of its function and the costs of its expression. Selection should drive the expression level of all proteins close to values that maximize fitness, particularly for high-expression proteins because of the increased energetic cost of production. Therefore, stabilizing selection may reduce the amount of standing expression variation for high-expression proteins, and in combination with physiological constraints that may place an upper bound on the range of beneficial expression variation, these constraints could severely limit the availability of beneficial expression variants. To determine whether rapid-expression evolution was restricted to low-expression proteins owing to these constraints on highly expressed proteins over ecological timescales, we compared venom protein expression levels across mainland and island populations for three species of pit vipers. We detected significant differentiation in protein expression levels in two of the three species and found that rapid-expression differentiation was restricted to low-expression proteins. Our results suggest that various constraints on high-expression proteins reduce the availability of beneficial expression variants relative to low-expression

  14. Expression of Contractile Protein Isoforms in Microgravity

    Science.gov (United States)

    Anderson, Page A. W.

    1996-01-01

    The general objective of this experiment is to determine the effect of space flight parameters, including microgravity, on ontogenesis and embryogenesis of Japanese quail. Nine U.S. and two Russian investigators are cooperating in this study. Specific objectives of the participating scientists include assessing the gross and microscopic morphological and histological development of the embryo, as well as the temporal and spacial development of specific cells, tissues, and organs. Temporally regulated production of specific proteins is also being investigated. Our objective is to determine the effects of microgravity on developmentally programmed expression of Troponin T and I isoforms known to regulate cardiac and skeletal muscle contraction.

  15. Hypoxia-inducible factor 1 alpha and vascular endothelial growth factor overexpression in ischemic colitis

    Institute of Scientific and Technical Information of China (English)

    Tomoyuki Okuda; Takeshi Azuma; Masahiro Ohtani; Ryuho Masaki; Yoshiyuki Ito; Yukinao Yamazaki; Shigeji Ito; Masaru Kuriyama

    2005-01-01

    AIM: To examine the etiology and pathophysiology in human ischemic colitis from the viewpoint of ischemic favors such as hypoxia-inducible factor 1 alpha (HIF-1alpha and vascular endothelial growth factor (VEGF).METHODS: Thirteen patients with ischemic colitis and 21 normal controls underwent colonoscopy. The follow-up colonoscopy was performed in 8 patients at 7 to 10 d after theoccurrence of ischemic colitis. Biopsy samples were subjected to real-time RT-PCR and immunohistochemistry to detect the expression of HIF-1 alpha and VEGF.RESULTS: HIF-1 alpha and VEGF expression were found in the normal colon tissues by RT-PCR and immunohistochemistry.HIF-1 alpha and VEGF were overexpressed in the lesions of ischemic colitis. Overexpressed HIF-1 alpha and VEGF RNA quickly decreased to the normal level in the scar regions at 7 to 10 d after the occurrence of ischemic colitis.CONCLUSION: Constant expression of HIF-1 alpha and VEGF in normal human colon tissue suggested that HIF-1alpha and VEGF play an important role in maintaining tissue integrity. We confirmed the ischemic crisis in ischemic colitis at the molecular level, demonstrating overexpression of HIF-1 alpha and VEGF in ischemic lesions. These ischemic factors may play an important role in the pathophysiology of ischemic colitis.

  16. The potential mechanism of tiliroside-dependent inhibition of t-butylhydroperoxide-induced oxidative stress in endometrial carcinoma cells.

    Science.gov (United States)

    Tomczyk, Michal; Tumanov, Aleksander; Zaniewska, Agnieszka; Surazynski, Arkadiusz

    2010-07-01

    The effects of oxidative stress on collagen and DNA biosynthesis, beta-galactosidase activity, the expression of the beta-integrin receptor, FAK, the insulin-like growth factor-I receptor (IGF-IR), the hypoxia-inducible factor-1 (HIF-1), and the mitogen-activated protein kinases (MAP/ERK(1), ERK(2)) were evaluated in human endometrial carcinoma cells. Subconfluent cells were subjected to oxidative stress with 30 microM t-butylhydroperoxide (t-BHP) for 1 h per day over the course of 5 days. It was found that oxidative stress contributed to an increase in the beta-galactosidase activity as well as to the inhibition of collagen and DNA biosynthesis. The mechanism of the process was found at the level of IGF-IR and HIF-1 alpha. An increase in the expression of HIF-1 alpha and a decrease in the expression of IGF-IR were observed in the cells subjected to oxidative stress. The role of IGF-IR signalling in the process was confirmed by an experiment showing downregulation of MAP kinases ERK(1) and ERK(2) expression in the studied cells. This phenomenon is probably responsible for the drastic inhibition of protein (up to 40 % of control) and DNA biosynthesis (up to 65 % of control) in the cells. An addition of tiliroside to the cells medium restored all parameters to the control level, including IGF-IR and HIF-1 alpha expressions. The data suggest that the antioxidative activity of tiliroside isolated from Potentilla argentea may originate at the level of IGF-IR and HIF-1 alpha signalling.

  17. Rapid detection of hypoxia-inducible factor-1-active tumours: pretargeted imaging with a protein degrading in a mechanism similar to hypoxia-inducible factor-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Masashi [Kyoto University, Radioisotopes Research Laboratory, Kyoto University Hospital, Faculty of Medicine, Kyoto (Japan); Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Kudo, Takashi; Konishi, Hiroaki; Miyano, Azusa; Ono, Masahiro; Saji, Hideo [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Kuge, Yuji [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan); Mukai, Takahiro [Kyushu University, Department of Biomolecular Recognition Chemistry, Graduate School of Pharmaceutical Sciences, Fukuoka (Japan); Tanaka, Shotaro; Kizaka-Kondoh, Shinae; Hiraoka, Masahiro [Kyoto University, Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto (Japan)

    2010-08-15

    Hypoxia-inducible factor-1 (HIF-1) plays an important role in malignant tumour progression. For the imaging of HIF-1-active tumours, we previously developed a protein, POS, which is effectively delivered to and selectively stabilized in HIF-1-active cells, and a radioiodinated biotin derivative, (3-{sup 123}I-iodobenzoyl)norbiotinamide ({sup 123}I-IBB), which can bind to the streptavidin moiety of POS. In this study, we aimed to investigate the feasibility of the pretargeting method using POS and {sup 123}I-IBB for rapid imaging of HIF-1-active tumours. Tumour-implanted mice were pretargeted with POS. After 24 h, {sup 125}I-IBB was administered and subsequently, the biodistribution of radioactivity was investigated at several time points. In vivo planar imaging, comparison between {sup 125}I-IBB accumulation and HIF-1 transcriptional activity, and autoradiography were performed at 6 h after the administration of {sup 125}I-IBB. The same sections that were used in autoradiographic analysis were subjected to HIF-1{alpha} immunohistochemistry. {sup 125}I-IBB accumulation was observed in tumours of mice pretargeted with POS (1.6%ID/g at 6 h). This result is comparable to the data derived from {sup 125}I-IBB-conjugated POS-treated mice (1.4%ID/g at 24 h). In vivo planar imaging provided clear tumour images. The tumoral accumulation of {sup 125}I-IBB significantly correlated with HIF-1-dependent luciferase bioluminescence (R=0.84, p<0.01). The intratumoral distribution of {sup 125}I-IBB was heterogeneous and was significantly correlated with HIF-1{alpha}-positive regions (R=0.58, p<0.0001). POS pretargeting with {sup 123}I-IBB is a useful technique in the rapid imaging and detection of HIF-1-active regions in tumours. (orig.)

  18. Engineering Escherichia coli for Functional Expression of Membrane Proteins

    NARCIS (Netherlands)

    Ho, Franz Y; Poolman, Bert

    2015-01-01

    A major bottleneck in the characterization of membrane proteins is low yield of functional protein in recombinant expression. Microorganisms are widely used for recombinant protein production, because of ease of cultivation and high protein yield. However, the target proteins do not always obtain th

  19. Recombinant Expression Screening of P. aeruginosa Bacterial Inner Membrane Proteins

    Directory of Open Access Journals (Sweden)

    Jeffery Constance J

    2010-11-01

    Full Text Available Abstract Background Transmembrane proteins (TM proteins make up 25% of all proteins and play key roles in many diseases and normal physiological processes. However, much less is known about their structures and molecular mechanisms than for soluble proteins. Problems in expression, solubilization, purification, and crystallization cause bottlenecks in the characterization of TM proteins. This project addressed the need for improved methods for obtaining sufficient amounts of TM proteins for determining their structures and molecular mechanisms. Results Plasmid clones were obtained that encode eighty-seven transmembrane proteins with varying physical characteristics, for example, the number of predicted transmembrane helices, molecular weight, and grand average hydrophobicity (GRAVY. All the target proteins were from P. aeruginosa, a gram negative bacterial opportunistic pathogen that causes serious lung infections in people with cystic fibrosis. The relative expression levels of the transmembrane proteins were measured under several culture growth conditions. The use of E. coli strains, a T7 promoter, and a 6-histidine C-terminal affinity tag resulted in the expression of 61 out of 87 test proteins (70%. In this study, proteins with a higher grand average hydrophobicity and more transmembrane helices were expressed less well than less hydrophobic proteins with fewer transmembrane helices. Conclusions In this study, factors related to overall hydrophobicity and the number of predicted transmembrane helices correlated with the relative expression levels of the target proteins. Identifying physical characteristics that correlate with protein expression might aid in selecting the "low hanging fruit", or proteins that can be expressed to sufficient levels using an E. coli expression system. The use of other expression strategies or host species might be needed for sufficient levels of expression of transmembrane proteins with other physical

  20. EGFR、Her-2、HIF-1α在食管鳞癌的表达及意义%Significance of EGFR, Her-2, and HIF-1α expression in esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    石祥东; 孟令新; 丁兆军; 孙树艳; 梁粉花; 王刚平

    2014-01-01

    Objective To explore EGFR, Her-2, HIF-1 alpha expression in esophageal squamous cell carcinoma(ESCC) and investigate the relationship between clinical pathological features in esophageal squamous carcinoma and the correlation between the three index. Methods Immunohistochemical Envision two-steps method was applied to assay EGFR, Her-2, HIF-1 alpha expression in 80 cases specimens of ESCC and 40 cases of adjacent normal squamous epithelial tissues. Results HIF-1 alpha, EGFR and Her-2 in ESCC and adjacent normal squamous epithelial tissues positive expression rate were 62.5% vs. 0.0% (P=0.000), 67.5% vs. 12.5% (P=0.000), 7.5% vs. 0.0% (P=0.183) each other. The expression of HIF-1 alpha, Her-2, EGFR had correlation with tumor cell differentiation, TNM staging and lymph node metastasis, had nothing to do with gender, age. HIF-1 alpha expression in esophageal squamous carcinoma had positive correlation with EGFR and Her-2, correlation coefficient were 0.565(P=0.000) and 0.221 (P=0.039). However, EGFR had no correlation with Her-2, correlation coefficient was 0.198(P=0.079). Conclusions EGFR and HIF-1 alpha high expression may plays an important role in tumor genesis and development of ESCC, may be used as useful indicators for predicating tumor genesis, metastasis, prognosis and may be likely to become new target for targeted therapy of ESCC. Her-2 expression was low in ESCC, and may be not suitable for be targeted therapy targets.%目的:研究EGFR、Her-2和HIF-1α在食管鳞癌中的表达,探讨三者的表达与食管鳞癌临床病理学特征之间的关系及三者之间的相关性。方法应用免疫组化 Envision 二步法检测80例食管鳞癌的切除标本和40例正常鳞状上皮组织中EGFR、Her-2和HIF-1α的表达。结果 HIF-1α、EGFR、Her-2在食管鳞癌及癌旁正常鳞状上皮组织表达阳性率分别为62.5%vs.0.0%(P=0.000)、67.5%vs.12.5%(P=0.000)和7.5%vs.0.0%(P=0.183)。HIF-1α、Her-2、EGFR表达

  1. Hypoxia-inducible factor-1α polymorphisms and TSC1/2 mutations are complementary in head and neck cancers

    Directory of Open Access Journals (Sweden)

    Nikitakis Nikolaos G

    2006-01-01

    Full Text Available Abstract Background Polymorphisms or mutations in hypoxia inducible factor-1 alpha (HIF-1alpha that increases its activity and stability under normoxia have recently been identified. Likewise, disruption of the TSC1/TSC2 complex through loss of TSC1 or TSC2 has been shown to result in abnormal accumulation of HIF-1α. Here, we investigate the novel polymorphisms in exon 12, that approximate the oxygen-dependent degradation domain of HIF-1alpha in five cell lines and 28 patients with oral squamous carcinomas. Moreover, we assess for the presence of polymorphisms and mutations in TSC1 and TSC2, to ascertain if dysregulation of such might complement HIF-1alpha expression. Results Denaturing high pressure liquid chromatography (DHPLC analysis on PCR fragments in exon 12 of HIF-1alpha from 28 patients with OSCC revealed that 6 of 28 patients had mismatched heteroduplex patterns. Genomic DNA was extracted from peripheral blood leukocytes and direct sequencing showed that in 5 of the six cases these changes represented polymorphisms while, one case was a somatic mutation. Analyses of TSC1 and TSC2 revealed heteroduplexes in exons: TSC1 exon 17; TSC2 exons 36,40, and 41. The relative levels of HIF-1alpha were significantly greater for tumors possessing a HIF-1alpha polymorphism or mutation within exon 12, whereas tumors possessing a deletion or polymorphism in TSC1/TSC2 displayed a trend for higher levels of HIF-1alpha. Western blot analyses for HIF-1alpha, TSC1 and TSC2 in five SCC cell lines revealed high levels of HIF-1alpha in SCC cells possessing TSC1 and/or TSC2 mutations. Wild-type TSC2 cells targeted with siRNA to TSC2 exhibited increased levels of HIF-1alpha. Transfection of a HIF-1alpha mutant produced higher levels of HIF-1alpha in TSC1/TSC2 mutant cell lines than in wild type cells. TSC1/TSC2 mutant cell lines administered Rapamycin blocked S6 phorphorylation and diminished the levels of HIF-1alpha to those observed in cell lines with wild

  2. Widely predicting specific protein functions based on protein-protein interaction data and gene expression profile

    Institute of Scientific and Technical Information of China (English)

    GAO Lei; LI Xia; GUO Zheng; ZHU MingZhu; LI YanHui; RAO ShaoQi

    2007-01-01

    GESTs (gene expression similarity and taxonomy similarity), a gene functional prediction approach previously proposed by us, is based on gene expression similarity and concept similarity of functional classes defined in Gene Ontology (GO). In this paper, we extend this method to protein-protein interaction data by introducing several methods to filter the neighbors in protein interaction networks for a protein of unknown function(s). Unlike other conventional methods, the proposed approach automatically selects the most appropriate functional classes as specific as possible during the learning process, and calls on genes annotated to nearby classes to support the predictions to some small-sized specific classes in GO. Based on the yeast protein-protein interaction information from MIPS and a dataset of gene expression profiles, we assess the performances of our approach for predicting protein functions to "biology process" by three measures particularly designed for functional classes organized in GO. Results show that our method is powerful for widely predicting gene functions with very specific functional terms. Based on the GO database published in December 2004, we predict some proteins whose functions were unknown at that time, and some of the predictions have been confirmed by the new SGD annotation data published in April, 2006.

  3. Widely predicting specific protein functions based on protein-protein interaction data and gene expression profile

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    GESTs (gene expression similarity and taxonomy similarity), a gene functional prediction approach previously proposed by us, is based on gene expression similarity and concept similarity of functional classes defined in Gene Ontology (GO). In this paper, we extend this method to protein-protein interac-tion data by introducing several methods to filter the neighbors in protein interaction networks for a protein of unknown function(s). Unlike other conventional methods, the proposed approach automati-cally selects the most appropriate functional classes as specific as possible during the learning proc-ess, and calls on genes annotated to nearby classes to support the predictions to some small-sized specific classes in GO. Based on the yeast protein-protein interaction information from MIPS and a dataset of gene expression profiles, we assess the performances of our approach for predicting protein functions to “biology process” by three measures particularly designed for functional classes organ-ized in GO. Results show that our method is powerful for widely predicting gene functions with very specific functional terms. Based on the GO database published in December 2004, we predict some proteins whose functions were unknown at that time, and some of the predictions have been confirmed by the new SGD annotation data published in April, 2006.

  4. Robust expression of a bioactive mammalian protein in Chlamydomonas chloroplast

    Energy Technology Data Exchange (ETDEWEB)

    Mayfield, Stephen P

    2015-01-13

    Methods and compositions are disclosed to engineer chloroplast comprising heterologous mammalian genes via a direct replacement of chloroplast Photosystem II (PSII) reaction center protein coding regions to achieve expression of recombinant protein above 5% of total protein. When algae is used, algal expressed protein is produced predominantly as a soluble protein where the functional activity of the peptide is intact. As the host algae is edible, production of biologics in this organism for oral delivery of proteins/peptides, especially gut active proteins, without purification is disclosed.

  5. Strain engineering for improved expression of recombinant proteins in bacteria.

    Science.gov (United States)

    Makino, Tomohiro; Skretas, Georgios; Georgiou, George

    2011-05-14

    Protein expression in Escherichia coli represents the most facile approach for the preparation of non-glycosylated proteins for analytical and preparative purposes. So far, the optimization of recombinant expression has largely remained a matter of trial and error and has relied upon varying parameters, such as expression vector, media composition, growth temperature and chaperone co-expression. Recently several new approaches for the genome-scale engineering of E. coli to enhance recombinant protein expression have been developed. These methodologies now enable the generation of optimized E. coli expression strains in a manner analogous to metabolic engineering for the synthesis of low-molecular-weight compounds. In this review, we provide an overview of strain engineering approaches useful for enhancing the expression of hard-to-produce proteins, including heterologous membrane proteins.

  6. Strain engineering for improved expression of recombinant proteins in bacteria

    OpenAIRE

    Skretas Georgios; Makino Tomohiro; Georgiou George

    2011-01-01

    Abstract Protein expression in Escherichia coli represents the most facile approach for the preparation of non-glycosylated proteins for analytical and preparative purposes. So far, the optimization of recombinant expression has largely remained a matter of trial and error and has relied upon varying parameters, such as expression vector, media composition, growth temperature and chaperone co-expression. Recently several new approaches for the genome-scale engineering of E. coli to enhance re...

  7. Calreticulin: Roles in Cell-Surface Protein Expression

    Directory of Open Access Journals (Sweden)

    Yue Jiang

    2014-09-01

    Full Text Available In order to perform their designated functions, proteins require precise subcellular localizations. For cell-surface proteins, such as receptors and channels, they are able to transduce signals only when properly targeted to the cell membrane. Calreticulin is a multi-functional chaperone protein involved in protein folding, maturation, and trafficking. However, evidence has been accumulating that calreticulin can also negatively regulate the surface expression of certain receptors and channels. In these instances, depletion of calreticulin enhances cell-surface expression and function. In this review, we discuss the role of calreticulin with a focus on its negative effects on the expression of cell-surface proteins.

  8. Expression and structural analysis of membrane proteins

    OpenAIRE

    Eifler, Nora

    2006-01-01

    1.1 Membrane Proteins Between one quarter and one third of all genes in eukaryotic and prokaryotic organisms code for integral membrane proteins (IMPs) (Essen, 2002). These proteins are essential parts of biological membranes and confer various functions, such as energy conversion, transport, biosynthesis of lipids, signal transduction, or cell recognition. The enormous economical potential of membrane proteins is highlighted by the family of G-protein-coupled receptors (GPC...

  9. Efficient protein production method for NMR using soluble protein tags with cold shock expression vector

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Kokoro [Fujifilm Corporation, Analysis Technology Center (Japan); Kojima, Chojiro, E-mail: kojima@protein.osaka-u.ac.j [Nara Institute of Science and Technology (NAIST), Graduate School of Biological Sciences (Japan)

    2010-11-15

    The E. coli protein expression system is one of the most useful methods employed for NMR sample preparation. However, the production of some recombinant proteins in E. coli is often hampered by difficulties such as low expression level and low solubility. To address these problems, a modified cold-shock expression system containing a glutathione S-transferase (GST) tag, the pCold-GST system, was investigated. The pCold-GST system successfully expressed 9 out of 10 proteins that otherwise could not be expressed using a conventional E. coli expression system. Here, we applied the pCold-GST system to 84 proteins and 78 proteins were successfully expressed in the soluble fraction. Three other cold-shock expression systems containing a maltose binding protein tag (pCold-MBP), protein G B1 domain tag (pCold-GB1) or thioredoxin tag (pCold-Trx) were also developed to improve the yield. Additionally, we show that a C-terminal proline tag, which is invisible in {sup 1}H-{sup 15}N HSQC spectra, inhibits protein degradation and increases the final yield of unstable proteins. The purified proteins were amenable to NMR analyses. These data suggest that pCold expression systems combined with soluble protein tags can be utilized to improve the expression and purification of various proteins for NMR analysis.

  10. Cloning and expression of special F protein from human liver

    Institute of Scientific and Technical Information of China (English)

    Shu-Ye Liu; Xin-Da Yu; Chun-Juan Song; Wei Lu; Jian-Dong Zhang; Xin-Rong Shi; Ying Duan; Ju Zhang

    2007-01-01

    AIM:To clone human liver special F protein and to express it in a prokaryotic system.METHODS:Total RNA was isolated from human liver tissue and first-strand cDNA was reverse transcribed using the PCR reverse primer. Following this,cDNA of the F protein was ligated into the clone vector pUCm-T. The segment of F protein's cDNA was subcloned into the expression vector pET-15b and transformed into E coli BL21 (DEB) pLyss. Isopropy-β-D-thiogalactoside (IPTG) was then used to induce expression of the target protein.RESULTS:The cDNA clone of human liver special F protein (1134bp) was successfully produced,with the cDNA sequence being published in Gene-bank:DQ188836. We confirmed the expression of F protein by Western blot with a molecular weight of 43 kDa. The expressed protein accounted for 40% of the total protein extracted.CONCLUSION:F protein expresses cDNA clone in a proKaryotic system,which offers a relatively simple way of producing sufficient quantities of F protein and contributes to understanding the principal biological functions of this protein.

  11. Boost protein expression through co-expression of LEA-like peptide in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Shinya Ikeno

    Full Text Available The boost protein expression has been done successfully by simple co-expression with a late embryogenesis abundant (LEA-like peptide in Escherichia coli. Frequently, overexpression of a recombinant protein fails to provide an adequate yield. In the study, we developed a simple and efficient system for overexpressing transgenic proteins in bacteria by co-expression with an LEA-like peptide. The design of this peptide was based on part of the primary structure of an LEA protein that is known hydrophilic protein to suppress aggregation of other protein molecules. In our system, the expression of the target protein was increased remarkably by co-expression with an LEA-like peptide consisting of only 11 amino acid residues. This could provide a practical method for producing recombinant proteins efficiently.

  12. Expression of potein complexes using multiple E. coli protein co-expression systems: a benchmarking study

    NARCIS (Netherlands)

    Busso, D.; Peleg, Y.; Folkers, G.E.; Celie, P.H.N.

    2011-01-01

    Escherichia coli (E. coli) remains the most commonly used host for recombinant protein expression. It is well known that a variety of experimental factors influence the protein production level as well as the solubility profile of over-expressed proteins. This becomes increasingly important for opti

  13. Expression, Solubilization, and Purification of Bacterial Membrane Proteins.

    Science.gov (United States)

    Jeffery, Constance J

    2016-02-02

    Bacterial integral membrane proteins play many important roles, including sensing changes in the environment, transporting molecules into and out of the cell, and in the case of commensal or pathogenic bacteria, interacting with the host organism. Working with membrane proteins in the lab can be more challenging than working with soluble proteins because of difficulties in their recombinant expression and purification. This protocol describes a standard method to express, solubilize, and purify bacterial integral membrane proteins. The recombinant protein of interest with a 6His affinity tag is expressed in E. coli. After harvesting the cultures and isolating cellular membranes, mild detergents are used to solubilize the membrane proteins. Protein-detergent complexes are then purified using IMAC column chromatography. Support protocols are included to help select a detergent for protein solubilization and for use of gel filtration chromatography for further purification.

  14. The dietary flavonoid kaempferol effectively inhibits HIF-1 activity and hepatoma cancer cell viability under hypoxic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mylonis, Ilias; Lakka, Achillia; Tsakalof, Andreas [Laboratory of Biochemistry, School of Medicine, University of Thessaly, BIOPOLIS, 41110 Larissa (Greece); Institute of Biomedical Research and Technology (BIOMED), 51 Papanastasiou str., 41222 Larissa (Greece); Simos, George, E-mail: simos@med.uth.gr [Laboratory of Biochemistry, School of Medicine, University of Thessaly, BIOPOLIS, 41110 Larissa (Greece); Institute of Biomedical Research and Technology (BIOMED), 51 Papanastasiou str., 41222 Larissa (Greece)

    2010-07-16

    Research highlights: {yields} Kaempferol inhibits HIF-1 activity in hepatocarcinoma cells; {yields} Kaempferol causes cytoplasmic mislocalization of HIF-1{alpha} by impairing the MAPK pathway. {yields} Viability of hepatocarcinoma cells under hypoxia is reduced by kaempferol. -- Abstract: Hepatocellular carcinoma (HCC) is characterized by high mortality rates and resistance to conventional treatment. HCC tumors usually develop local hypoxia, which stimulates proliferation of cancer cells and renders them resilient to chemotherapy. Adaptation of tumor cells to the hypoxic conditions depends on the hypoxia-inducible factor 1 (HIF-1). Over-expression of its regulated HIF-1{alpha} subunit, an important target of anti-cancer therapy, is observed in many cancers including HCC and is associated with severity of tumor growth and poor patient prognosis. In this report we investigate the effect of the dietary flavonoid kaempferol on activity, expression levels and localization of HIF-1{alpha} as well as viability of human hepatoma (Huh7) cancer cells. Treatment of Huh7 cells with kaempferol under hypoxic conditions (1% oxygen) effectively inhibited HIF-1 activity in a dose-dependent manner (IC{sub 50} = 5.16 {mu}M). The mechanism of this inhibition did not involve suppression of HIF-1{alpha} protein levels but rather its mislocalization into the cytoplasm due to inactivation of p44/42 MAPK by kaempferol (IC{sub 50} = 4.75 {mu}M). Exposure of Huh7 cells to 10 {mu}{Mu} kaempferol caused significant reduction of their viability, which was remarkably more evident under hypoxic conditions. In conclusion, kaempferol, a non-toxic natural food component, inhibits both MAPK and HIF-1 activity at physiologically relevant concentrations (5-10 {mu}M) and suppresses hepatocarcinoma cell survival more efficiently under hypoxia. It has, therefore, potential as a therapeutic or chemopreventive anti-HCC agent.

  15. Effect of oxygen on cardiac differentiation in mouse iPS cells: role of hypoxia inducible factor-1 and Wnt/beta-catenin signaling.

    Directory of Open Access Journals (Sweden)

    Tanya L Medley

    Full Text Available BACKGROUND: Disturbances in oxygen levels have been found to impair cardiac organogenesis. It is known that stem cells and differentiating cells may respond variably to hypoxic conditions, whereby hypoxia may enhance stem cell pluripotency, while differentiation of multiple cell types can be restricted or enhanced under hypoxia. Here we examined whether HIF-1alpha modulated Wnt signaling affected differentiation of iPS cells into beating cardiomyocytes. OBJECTIVE: We investigated whether transient and sustained hypoxia affects differentiation of cardiomyocytes derived from murine induced pluripotent stem (iPS cells, assessed the involvement of HIF-1alpha (hypoxia-inducible factor-1alpha and the canonical Wnt pathway in this process. METHODS: Embryoid bodies (EBs derived from iPS cells were differentiated into cardiomyocytes and were exposed either to 24 h normoxia or transient hypoxia followed by a further 13 days of normoxic culture. RESULTS: At 14 days of differentiation, 59 ± 2% of normoxic EBs were beating, whilst transient hypoxia abolished beating at 14 days and EBs appeared immature. Hypoxia induced a significant increase in Brachyury and islet-1 mRNA expression, together with reduced troponin C expression. Collectively, these data suggest that transient and sustained hypoxia inhibits maturation of differentiating cardiomyocytes. Compared to normoxia, hypoxia increased HIF-1alpha, Wnt target and ligand genes in EBs, as well as accumulation of HIF-1alpha and beta-catenin in nuclear protein extracts, suggesting involvement of the Wnt/beta-catenin pathway. CONCLUSION: Hypoxia impairs cardiomyocyte differentiation and activates Wnt signaling in undifferentiated iPS cells. Taken together the study suggests that oxygenation levels play a critical role in cardiomyocyte differentiation and suggest that hypoxia may play a role in early cardiogenesis.

  16. A highly efficient pipeline for protein expression in Leishmania tarentolae using infrared fluorescence protein as marker

    Directory of Open Access Journals (Sweden)

    Mueller-Roeber Bernd

    2010-05-01

    Full Text Available Abstract Background Leishmania tarentolae, a unicellular eukaryotic protozoan, has been established as a novel host for recombinant protein production in recent years. Current protocols for protein expression in Leishmania are, however, time consuming and require extensive lab work in order to identify well-expressing cell lines. Here we established an alternative protein expression work-flow that employs recently engineered infrared fluorescence protein (IFP as a suitable and easy-to-handle reporter protein for recombinant protein expression in Leishmania. As model proteins we tested three proteins from the plant Arabidopsis thaliana, including a NAC and a type-B ARR transcription factor. Results IFP and IFP fusion proteins were expressed in Leishmania and rapidly detected in cells by deconvolution microscopy and in culture by infrared imaging of 96-well microtiter plates using small cell culture volumes (2 μL - 100 μL. Motility, shape and growth of Leishmania cells were not impaired by intracellular accumulation of IFP. In-cell detection of IFP and IFP fusion proteins was straightforward already at the beginning of the expression pipeline and thus allowed early pre-selection of well-expressing Leishmania clones. Furthermore, IFP fusion proteins retained infrared fluorescence after electrophoresis in denaturing SDS-polyacrylamide gels, allowing direct in-gel detection without the need to disassemble cast protein gels. Thus, parameters for scaling up protein production and streamlining purification routes can be easily optimized when employing IFP as reporter. Conclusions Using IFP as biosensor we devised a protocol for rapid and convenient protein expression in Leishmania tarentolae. Our expression pipeline is superior to previously established methods in that it significantly reduces the hands-on-time and work load required for identifying well-expressing clones, refining protein production parameters and establishing purification protocols

  17. Expression of Helicobacter pylori Hsp60 protein and its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Liang-Ren Li; Ji-De Wang; Ye Chen; Jian-Feng Jin; Zhao-Shan Zhang; Dian-Yuan Zhou; Ya-Li Zhang

    2003-01-01

    AIM: To express Hsp60 protein of H pylori by a constructed vector and to evaluate its immunogenicity.METHODS: Hsp60 DNA was amplified by PCR and inserted into the prokaryotie expression vector pET-22b (+), which was transformed into BL21 (DE3) E. coli strain to express recombinant protein. Immunogenicity of expressed Hsp60 protein was evaluated with animal experiments.RESULTS: DNA sequence analysis showed Hsp60 DNA was the same as GenBank's research. Hsp60 recombinant protein accounted for 27.2 % of the total bacterial protein,and could be recognized by the serum from H pylori infected patients and Balb/c mice immunized with Hsp60 itself.CONCLUSION: Hsp60 recombinant protein might become a potential vaccine for controlling and treating H pylori infection.

  18. Evaluation of somatic embryos of alfalfa for recombinant protein expression.

    Science.gov (United States)

    Fu, Guohua; Grbic, Vojislava; Ma, Shengwu; Tian, Lining

    2015-02-01

    Somatic embryos of alfalfa can accumulate higher levels of recombinant proteins comparing to vegetative organs. Somatic embryos may be explored as a new system for new protein production for plants. Plants have been explored via genetic engineering as an inexpensive system for recombinant protein production. However, protein expression levels in vegetative tissues have been low, which limits the commercial utilization of plant expression systems. Somatic embryos resemble zygotic embryos in many aspects and may accumulate higher levels of proteins as true seed. In this study, somatic embryo of alfalfa (Medicago sativa L.) was investigated for the expression of recombinant proteins. Three heterologous genes, including the standard scientific reporter uid that codes for β-glucuronidase and two genes of interest: ctb coding for cholera toxin B subunit (CTB), and hIL-13 coding for human interleukin 13, were independently introduced into alfalfa via Agrobacterium-mediated transformation. Somatic embryos were subsequently induced from transgenic plants carrying these genes. Somatic embryos accumulated approximately twofold more recombinant proteins than vegetative organs including roots, stems, and leaves. The recombinant proteins of CTB and hIL-13 accumulated up to 0.15 and 0.18 % of total soluble protein in alfalfa somatic embryos, respectively. The recombinant proteins expressed in somatic embryos also exhibited biological activities. As somatic embryos can be induced in many plant species and their production can be scaled up via different avenues, somatic embryos may be developed as an efficient expression system for recombinant protein production.

  19. Maltose-Binding Protein (MBP, a Secretion-Enhancing Tag for Mammalian Protein Expression Systems.

    Directory of Open Access Journals (Sweden)

    Raphael Reuten

    Full Text Available Recombinant proteins are commonly expressed in eukaryotic expression systems to ensure the formation of disulfide bridges and proper glycosylation. Although many proteins can be expressed easily, some proteins, sub-domains, and mutant protein versions can cause problems. Here, we investigated expression levels of recombinant extracellular, intracellular as well as transmembrane proteins tethered to different polypeptides in mammalian cell lines. Strikingly, fusion of proteins to the prokaryotic maltose-binding protein (MBP generally enhanced protein production. MBP fusion proteins consistently exhibited the most robust increase in protein production in comparison to commonly used tags, e.g., the Fc, Glutathione S-transferase (GST, SlyD, and serum albumin (ser alb tag. Moreover, proteins tethered to MBP revealed reduced numbers of dying cells upon transient transfection. In contrast to the Fc tag, MBP is a stable monomer and does not promote protein aggregation. Therefore, the MBP tag does not induce artificial dimerization of tethered proteins and provides a beneficial fusion tag for binding as well as cell adhesion studies. Using MBP we were able to secret a disease causing laminin β2 mutant protein (congenital nephrotic syndrome, which is normally retained in the endoplasmic reticulum. In summary, this study establishes MBP as a versatile expression tag for protein production in eukaryotic expression systems.

  20. Plant Antifreeze Proteins and Their Expression Regulatory Mechanism

    Institute of Scientific and Technical Information of China (English)

    Lin Yuan-zhen; Lin Shan-zhi; Zhang Zhi-yi; Zhang Wei; Liu Wen-feng

    2005-01-01

    Low temperature is one of the major limiting environmental factors which constitutes the growth, development,productivity and distribution of plants. Over the past several years, the proteins and genes associated with freezing resistance of plants have been widely studied. The recent progress of domestic and foreign research on plant antifreeze proteins and the identification and characterization of plant antifreeze protein genes, especially on expression regulatory mechanism of plant antifreeze proteins are reviewed in this paper. Finally, some unsolved problems and the trend of research in physiological functions and gene expression regulatory mechanism of plant antifreeze proteins are discussed.

  1. Effects of immunosuppressive treatment on protein expression in rat kidney

    Directory of Open Access Journals (Sweden)

    Kędzierska K

    2014-09-01

    Full Text Available Karolina Kędzierska,1 Katarzyna Sporniak-Tutak,2 Krzysztof Sindrewicz,2 Joanna Bober,3 Leszek Domański,1 Mirosław Parafiniuk,4 Elżbieta Urasińska,5 Andrzej Ciechanowicz,6 Maciej Domański,1 Tomasz Smektała,2 Marek Masiuk,5 Wiesław Skrzypczak,6 Małgorzata Ożgo,6 Joanna Kabat-Koperska,1 Kazimierz Ciechanowski1 1Department of Nephrology, Transplantology, and Internal Medicine, 2Department of Dental Surgery, 3Department of Medical Chemistry, 4Department of Forensic Medicine, 5Department of Pathomorphology, Pomeranian Medical University, 6Department of Physiology, Cytobiology, and Proteomics, West Pomeranian University of Technology, Szczecin, Poland Abstract: The structural proteins of renal tubular epithelial cells may become a target for the toxic metabolites of immunosuppressants. These metabolites can modify the properties of the proteins, thereby affecting cell function, which is a possible explanation for the mechanism of immunosuppressive agents' toxicity. In our study, we evaluated the effect of two immunosuppressive strategies on protein expression in the kidneys of Wistar rats. Fragments of the rat kidneys were homogenized after cooling in liquid nitrogen and then dissolved in lysis buffer. The protein concentration in the samples was determined using a protein assay kit, and the proteins were separated by two-dimensional electrophoresis. The obtained gels were then stained with Coomassie Brilliant Blue, and their images were analyzed to evaluate differences in protein expression. Identification of selected proteins was then performed using mass spectrometry. We found that the immunosuppressive drugs used in popular regimens induce a series of changes in protein expression in target organs. The expression of proteins involved in drug, glucose, amino acid, and lipid metabolism was pronounced. However, to a lesser extent, we also observed changes in nuclear, structural, and transport proteins' synthesis. Very slight differences

  2. [Effects of feixin decoction on the contents of hypoxia-inducible factor-1alpha and vascular endothelial growth factor in the rat model of hypoxic pulmonary hypertension].

    Science.gov (United States)

    He, Hong-Jun; Dai, Ai-Guo

    2012-05-01

    To explore the effects of Feixin Decoction (FXD) on the hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) in the rat model of hypoxic pulmonary hypertension (HPH), and to study its mechanisms for treating HPH. Forty healthy male SD rats were randomly divided into four groups, i. e., the normal control group, the HPH model group, the FXD group, and the Nifedipine group, 10 rats in each group. The HPH rat model was prepared using normal pressure intermittent hypoxia method. Except the normal control group, rats in the rest groups were fed in a self-made hypoxic plexiglass cabin, with the poor oxygen condition for 8 h daily for 14 successive days. Then the distilled water (at 30 mL/kg) was given by gastrogavage to rats in the normal control group and the HPH model group. FXD (at 28 g/kg) and Nifedipine (at 20 mg/kg) were given by gastrogavage to rats in the FXD group and the Nifedipine group respectively, once daily, for 14 successive days. Besides, hypoxia was continued for 14 days while medicating. The mean pulmonary artery pressure (mPAP) was detected on the second day after the last medication. The morphology of the pulmonary arteriole was detected. The ratio of pulmonary artery wall area and tube area (WA%) was determined. The protein and mRNA expressions of HIF-1alpha and VEGF were detected using immunohistochemistry and in situ hybridization technique. Compared with the normal control group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly increased in the model group (P model group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly decreased in the FXD group (P < 0.01, P < 0.05). FXD down-regulated the expression of VEGF through decreasing the expression of HIF-1alpha. One of its mechanisms for treating HPH might be partially due to reversing the remodeling of pulmonary vascular smooth muscle.

  3. A STUDY ON CYCLOOXYGENASE -2 PROTEIN EXPRESSION IN ESOPHAGEAL CAICONOGENESIS

    Institute of Scientific and Technical Information of China (English)

    王立峰; 张伟; 王吾如; 王洪平; 韩双廷; 曲平; 刘义; 李茉; 刘伯齐; 林培中

    2001-01-01

    To investigate cyclooxygenase- 2(Cox-2) protein expression in esophageal cancer and precancerous lesions. Methods: One hundred twenty biopsy specimens from esophageal carcinoma and 113 from patients with esophageal premalingnant lesions, 27 from individuals with normal esophageal mucosa and 3 from Barrett's esophagus were examined for Cox-2 protein expression by immunohistochemistry. Results: Cox-2 protein was not observed in normal esophageal squamous and glandular epithelium, hyperplasia from mild to severe dysplasia lesions and carcinoma in situ. Positive Cox-2 protein expression was found in 4 of 60 specimens of invasive squamous-cell carcinomas, 21 of 30 specimens of esophageal adenocarcinomas and in 3 of 3 Barret's esophageal tissues. Conclusion: The Cox-2 protein expression may be associated with the development of the esophageal adenocarcinomas but not esophageal squamous-cell carcinomas.

  4. Insulin influenced expression of myelin proteins in diabetic peripheral neuropathy.

    Science.gov (United States)

    Rachana, Kuruvanthe S; Manu, Mallahalli S; Advirao, Gopal M

    2016-08-26

    Diabetic peripheral neuropathy (DPN) is one of the downstream complications of diabetes. This complication is caused by the deficiency of insulin action and subsequent hyperglycemia, but the details of their pathogenesis remain unclear. Hence, it is of critical importance to understand how such hormonal variation affects the expression of myelin proteins such as myelin basic protein (MBP) and myelin associated glycoprotein (MAG) in the peripheral nerve. An earlier report from our lab has demonstrated the expression of insulin receptors (IR) in Schwann cells (SCs) of sciatic nerve. To assess the neurotrophic role of insulin in diabetic neuropathy, we studied the expression of these myelin proteins under control, DPN and insulin treated DPN subjects at developmental stages. Further, the expression of these myelin proteins was correlated with the expression of insulin receptor. Expression of myelin proteins was significantly reduced in the diabetic model compared to normal, and upregulated in insulin treated diabetic rats. Similarly, an in vitro study was also carried out in SCs grown at high glucose and insulin treated conditions. The expression pattern of myelin proteins in SCs was comparable to that of in vivo samples. In addition, quantitative study of myelin genes by real time PCR has also showed the significant expression pattern change in the insulin treated and non-treated DPN subjects. Taken together, these results corroborate the critical importance of insulin as a neurotrophic factor in demyelinized neurons in diabetic neuropathy.

  5. High expression of arachidonate 15-lipoxygenase and proinflammatory markers in human ischemic heart tissue

    Energy Technology Data Exchange (ETDEWEB)

    Magnusson, Lisa U.; Lundqvist, Annika [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden); Asp, Julia [Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg (Sweden); Synnergren, Jane [Systems Biology Research Center, School of Life Sciences, University of Skoevde, Skoevde (Sweden); Johansson, Cecilia Thalen [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden); Palmqvist, Lars [Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg (Sweden); Jeppsson, Anders [Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg (Sweden); Hulten, Lillemor Mattsson, E-mail: Lillemor.Mattsson@wlab.gu.se [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden)

    2012-07-27

    Highlights: Black-Right-Pointing-Pointer We found a 17-fold upregulation of ALOX15 in the ischemic heart. Black-Right-Pointing-Pointer Incubation of human muscle cells in hypoxia showed a 22-fold upregulation of ALOX15. Black-Right-Pointing-Pointer We observed increased levels of proinflammatory markers in ischemic heart tissue. Black-Right-Pointing-Pointer Suggesting a link between ischemia and inflammation in ischemic heart biopsies. -- Abstract: A common feature of the ischemic heart and atherosclerotic plaques is the presence of hypoxia (insufficient levels of oxygen in the tissue). Hypoxia has pronounced effects on almost every aspect of cell physiology, and the nuclear transcription factor hypoxia inducible factor-1{alpha} (HIF-1{alpha}) regulates adaptive responses to low concentrations of oxygen in mammalian cells. In our recent work, we observed that hypoxia increases the proinflammatory enzyme arachidonate 15-lipoxygenase (ALOX15B) in human carotid plaques. ALOX15 has recently been shown to be present in the human myocardium, but the effect of ischemia on its expression has not been investigated. Here we test the hypothesis that ischemia of the heart leads to increased expression of ALOX15, and found an almost 2-fold increase in HIF-1{alpha} mRNA expression and a 17-fold upregulation of ALOX15 mRNA expression in the ischemic heart biopsies from patients undergoing coronary bypass surgery compared with non ischemic heart tissue. To investigate the effect of low oxygen concentration on ALOX15 we incubated human vascular muscle cells in hypoxia and showed that expression of ALOX15 increased 22-fold compared with cells incubated in normoxic conditions. We also observed increased mRNA levels of proinflammatory markers in ischemic heart tissue compared with non-ischemic controls. In summary, we demonstrate increased ALOX15 in human ischemic heart biopsies. Furthermore we demonstrate that hypoxia increases ALOX15 in human muscle cells. Our results yield

  6. Clinical significance of PHPT1 protein expression in lung cancer

    Institute of Scientific and Technical Information of China (English)

    XU An-jian; XIA Xiang-hou; DU Song-tao; GU Jun-chao

    2010-01-01

    Background in our previous studies, we found the expression of 14-kD phosphohistidine phosphatase (PHPT1) was associated with lung cancer cells migration and invasion, and PHPT1 mRNA expression level in lung cancer tissues clinically correlated with lymph node metastasis. in the present study, we aimed to further investigate the expression of PHPT1 protein in lung cancer.Methods Expression of PHPT1 protein in tissue samples from 146 lung cancers and 30 normal tissues adjacent to lung cancers was assessed using immunohistochemical method. Fisher's exact test was used to analyze expression patterns of PHPT1 protein in these tissue types. Meanwhile, we studied the correlation between expression of PHPT1 protein and clinicopathological features in lung cancer.Results Significantly higher expression levels of PHPT1 protein were found in lung cancer samples (53.42%) than in normal tissues adjacent to lung cancer (23.33%) (P=0.003). Fisher's exact test showed that lung cancer stage positively correlated with expression of PHPT1 protein (P=0.02), and lung cancer samples with lymph node metastasis showed higher PHPT1 protein expression (P=0.016) than the samples without lymph node metastasis.Conclusions The results of this study agree with findings from our previous study of PHPT1 mRNA expression in lung cancer tissues, and strongly suggest that PHPT1 protein is closely associated with the carcinogenesis and metastasis of lung cancer. Thus, therapy targeting PHPT1 (inhibition or silencing) could be potentially benefited for lung cancer patients.

  7. Stable protein expression in mammalian cells using baculoviruses.

    Science.gov (United States)

    Lackner, Andreas; Kreidl, Emanuel; Peter-Vörösmarty, Barbara; Spiegl-Kreinecker, Sabine; Berger, Walter; Grusch, Michael

    2012-01-01

    The baculovirus Autographa californica multiple nuclear polyhedrosis virus (AcMNPV) has been widely used in biotechnology for protein expression in insect cells. Baculoviruses use arthropods as their natural hosts and are unable to replicate in mammalian cells. However, AcMNPV is able to enter many mammalian cell types and can be used for transgene expression if engineered to contain suitable expression cassettes. In this chapter, we describe the construction and application of a recombinant baculovirus containing a bicistronic expression cassette that can be used for stable protein expression in mammalian cells. As an example, the generation of glioblastoma and hepatocellular carcinoma cell lines stably expressing green fluorescent protein after puromycin selection is shown.

  8. Chemometrics of differentially expressed proteins from colorectal cancer patients

    Institute of Scientific and Technical Information of China (English)

    Lay-Chin Yeoh; Saravanan Dharmaraj; Boon-Hui Gooi; Manjit Singh; Lay-Harn Gam

    2011-01-01

    AIM: To evaluate the usefulness of differentially expressed proteins from colorectal cancer (CRC) tissues for differentiating cancer and normal tissues. METHODS: A Proteomic approach was used to identify the differentially expressed proteins between CRC and normal tissues. The proteins were extracted using Tris buffer and thiourea lysis buffer (TLB) for extraction of aqueous soluble and membrane-associated proteins, respectively. Chemometrics, namely principal component analysis (PCA) and linear discriminant analysis (LDA), were used to assess the usefulness of these proteins for identifying the cancerous state of tissues. RESULTS: Differentially expressed proteins identified were 37 aqueous soluble proteins in Tris extracts and 24 membrane-associated proteins in TLB extracts. Based on the protein spots intensity on 2D-gel images, PCA by applying an eigenvalue > 1 was successfully used to reduce the number of principal components (PCs) into 12 and seven PCs for Tris and TLB extracts, respectively, and subsequently six PCs, respectively from both the extracts were used for LDA. The LDA classification for Tris extract showed 82.7% of original samples were correctly classified, whereas 82.7% were correctly classified for the cross-validated samples. The LDA for TLB extract showed that 78.8% of original samples and 71.2% of the cross-validated samples were correctly classified. CONCLUSION: The classification of CRC tissues by PCA and LDA provided a promising distinction between normal and cancer types. These methods can possibly be used for identification of potential biomarkers among the differentially expressed proteins identified.

  9. Expression of a Carrot Antifreeze Protein Gene in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Ma Xinyu; Shen Xin; Lu Cunfu

    2003-01-01

    The recombinant expression vectorpET43. lb-AFP, which contains full encoding region of a carrot 36 kD antifreeze protein (AFP) gene was constructed. The recombinant was transformed into expression host carrying T7 RNA polymerase gene (DE3 lysogen) and induced by 1 mmol. L-1 IPTG (isopropyl-β-D-thiogalactoside) to express 110 kD polypeptide of AFP fusion protein.The analysis of product solubility revealed that pET43. 1b-AFP was predominately soluble, and the expressed amount reached the maximum after the IPTG treatment for 3 h.

  10. Analysis of interferon gamma protein expression in zebrafish (Danio rerio).

    Science.gov (United States)

    Yoon, Sohye; Alnabulsi, Ayham; Wang, Ting Yu; Lee, Po Tsang; Chen, Tzong-Yueh; Bird, Steve; Zou, Jun; Secombes, Christopher J

    2016-10-01

    IFN-γ is a major effector cytokine, produced to induce type I immune responses. It has been cloned in several fish species including zebrafish, however to date few studies have looked at IFN-γ protein expression and bioactivity in fish. Hence, the current study focused on developing a monoclonal antibody (moAb) against zfIFN-γ. We show that the zfIFN-γ moAb specifically recognises E. coli produced recombinant IFN-γ protein and zfIFN-γ produced in transfected HEK293 cells, by Western blot analysis. Next we analysed the production of the native protein following expression induced by PHA stimulation of leukocytes in vitro or antigen re-stimulation in vivo. We show the IFN-γ protein is produced as a dimer, and that a good correlation exists between transcript expression levels and protein levels.

  11. Heterologous Protein Expression by Lactococcus lactis

    NARCIS (Netherlands)

    Villatoro-Hernández, J.; Kuipers, O.P.; Saucedo-Cárdenas, O.; Montes-de-Oca-Luna, R.

    2012-01-01

    This chapter describes the use of Lactococcus lactis as a safe and efficient cell factory to produce heterologous proteins of medical interest. The relevance of the use of this lactic acid bacterium (LAB) is that it is a noncolonizing, nonpathogenic microorganism that can be delivered in vivo at a m

  12. Immunohistochemical expression of latent membrane protein 1 ...

    African Journals Online (AJOL)

    EB

    2013-09-03

    Sep 3, 2013 ... Department of Pathology, Ibn Rochd University Medical Center, Casablanca, ... NPC is a characteristic tumor displaying epidemiological, genetic and regional distribution properties that ... expression and histological type, age and sex distributions was ..... according to geographical location and we could.

  13. Expression of Yes-associated protein modulates Survivin expression in primary liver malignancies.

    Science.gov (United States)

    Bai, Haibo; Gayyed, Mariana F; Lam-Himlin, Dora M; Klein, Alison P; Nayar, Suresh K; Xu, Yang; Khan, Mehtab; Argani, Pedram; Pan, Duojia; Anders, Robert A

    2012-09-01

    Hepatocellular carcinoma and intrahepatic cholangiocarcinoma account for 95% of primary liver cancer. For each of these malignancies, the outcome is dismal; incidence is rapidly increasing, and mechanistic understanding is limited. We observed abnormal proliferation of both biliary epithelium and hepatocytes in mice after genetic manipulation of Yes-associated protein, a transcription coactivator. Here, we comprehensively documented Yes-associated protein expression in the human liver and primary liver cancers. We showed that nuclear Yes-associated protein expression is significantly increased in human intrahepatic cholangiocarcinoma and hepatocellular carcinoma. We found that increased Yes-associated protein levels in hepatocellular carcinoma are due to multiple mechanisms including gene amplification and transcriptional and posttranscriptional regulation. Survivin, a member of the inhibitors-of-apoptosis protein family, has been reported as an independent prognostic factor for poor survival in both hepatocellular carcinoma and intrahepatic cholangiocarcinoma. We found that nuclear Yes-associated protein expression correlates significantly with nuclear Survivin expression for both intrahepatic cholangiocarcinoma and hepatocellular carcinoma. Furthermore, using mice engineered to conditionally overexpress Yes-associated protein in the liver, we found that Survivin messenger RNA expression depends upon Yes-associated protein levels. Our findings suggested that Yes-associated protein contributes to primary liver tumorigenesis and likely mediates its oncogenic effects through modulating Survivin expression.

  14. Performance benchmarking of four cell-free protein expression systems.

    Science.gov (United States)

    Gagoski, Dejan; Polinkovsky, Mark E; Mureev, Sergey; Kunert, Anne; Johnston, Wayne; Gambin, Yann; Alexandrov, Kirill

    2016-02-01

    Over the last half century, a range of cell-free protein expression systems based on pro- and eukaryotic organisms have been developed and have found a range of applications, from structural biology to directed protein evolution. While it is generally accepted that significant differences in performance among systems exist, there is a paucity of systematic experimental studies supporting this notion. Here, we took advantage of the species-independent translation initiation sequence to express and characterize 87 N-terminally GFP-tagged human cytosolic proteins of different sizes in E. coli, wheat germ (WGE), HeLa, and Leishmania-based (LTE) cell-free systems. Using a combination of single-molecule fluorescence spectroscopy, SDS-PAGE, and Western blot analysis, we assessed the expression yields, the fraction of full-length translation product, and aggregation propensity for each of these systems. Our results demonstrate that the E. coli system has the highest expression yields. However, we observe that high expression levels are accompanied by production of truncated species-particularly pronounced in the case of proteins larger than 70 kDa. Furthermore, proteins produced in the E. coli system display high aggregation propensity, with only 10% of tested proteins being produced in predominantly monodispersed form. The WGE system was the most productive among eukaryotic systems tested. Finally, HeLa and LTE show comparable protein yields that are considerably lower than the ones achieved in the E. coli and WGE systems. The protein products produced in the HeLa system display slightly higher integrity, whereas the LTE-produced proteins have the lowest aggregation propensity among the systems analyzed. The high quality of HeLa- and LTE-produced proteins enable their analysis without purification and make them suitable for analysis of multi-domain eukaryotic proteins.

  15. Small-scale expression of proteins in E. coli.

    Science.gov (United States)

    Zerbs, Sarah; Giuliani, Sarah; Collart, Frank

    2014-01-01

    Proteins participate in virtually every cellular activity, and a knowledge of protein function is essential for an understanding of biological systems. However, protein diversity necessitates the application of an array of in vivo and in vitro approaches for characterization of the functional and biochemical properties of proteins. Methods that enable production of proteins for in vitro studies are critical for determination of the molecular, kinetic, and thermodynamic properties of these molecules. Ideally, proteins could be purified from the original source; however, the native host is often unsuitable for a number of reasons. Consequently, systems for heterologous protein production are commonly used to produce large amounts of protein. Heterologous expression hosts are chosen using a number of criteria, including genetic tractability, advantageous production or processing characteristics (secretion or posttranslational modifications), or economy of time and growth requirements. The subcloning process also provides an opportunity to introduce purification tags, epitope tags, fusions, truncations, and mutations into the coding sequence that may be useful in downstream purification or characterization applications. Bacterial systems for heterologous protein expression have advantages in ease of use, cost, short generation times, and scalability. These expression systems have been widely used by high-throughput protein production projects and often represent an initial experiment for any expression target. Escherichia coli has been studied for many years as a model bacterial organism and is one of the most popular hosts for heterologous protein expression (Terpe, 2006). Its protein production capabilities have been intensively studied, and the ease of genetic manipulation in this organism has led to the development of strains engineered exclusively for use in protein expression. These resources are widely available from commercial sources and public repositories

  16. Genome-wide screens for expressed hypothetical proteins

    DEFF Research Database (Denmark)

    Madsen, Claus Desler; Durhuus, Jon Ambæk; Rasmussen, Lene Juel

    2012-01-01

    A hypothetical protein (HP) is defined as a protein that is predicted to be expressed from an open reading frame, but for which there is no experimental evidence of translation. HPs constitute a substantial fraction of proteomes of human as well as of other organisms. With the general belief...

  17. Improved means and methods for expressing recombinant proteins

    NARCIS (Netherlands)

    Poolman, Berend; Martinez Linares, Daniel; Gul, Nadia

    2014-01-01

    The invention relates to the field of genetic engineering and the production of recombinant proteins in microbial host cells. Provided is a method for enhanced expression of a recombinant protein of interest in a microbial host cell, comprising providing a microbial host cell wherein the function of

  18. Patterns of fluorescent protein expression in Scleractinian corals.

    Science.gov (United States)

    Gruber, David F; Kao, Hung-Teh; Janoschka, Stephen; Tsai, Julia; Pieribone, Vincent A

    2008-10-01

    Biofluorescence exists in only a few classes of organisms, with Anthozoa possessing the majority of species known to express fluorescent proteins. Most species within the Anthozoan subgroup Scleractinia (reef-building corals) not only express green fluorescent proteins, they also localize the proteins in distinct anatomical patterns.We examined the distribution of biofluorescence in 33 coral species, representing 8 families, from study sites on Australia's Great Barrier Reef. For 28 of these species, we report the presence of biofluorescence for the first time. The dominant fluorescent emissions observed were green (480-520 nm) and red (580-600 nm). Fluorescent proteins were expressed in three distinct patterns (highlighted, uniform, and complementary) among specific anatomical structures of corals across a variety of families. We report no significant overlap between the distribution of fluorescent proteins and the distribution of zooxanthellae. Analysis of the patterns of fluorescent protein distribution provides evidence that the scheme in which fluorescent proteins are distributed among the anatomical structures of corals is nonrandom. This targeted expression of fluorescent proteins in corals produces contrast and may function as a signaling mechanism to organisms with sensitivity to specific wavelengths of light.

  19. Controlled expression of enhanced green fluorescent protein and hepatitis B virus precore protein in mammalian cells

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A novel tetracycline regulation expression system was used to regulate the expression of enhanced green fluorescent protein (EGFP) and hepatitis B virus precore protein in the mammalian cell lines with lipofectAMINE. Flow cytometry assays showed that application of the system resulted in about 18-fold induction of EGFP expression in CHO cell lines and 5-fold induction in SSMC-7721 cells and about 2-fold in the HEK293 cells. Furthermore, the effective use of this system for the controlled expression of HBV precore protein gene in hepatocellular carcinoma cells was tested.

  20. The proteome response to amyloid protein expression in vivo.

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    Ricardo A Gomes

    Full Text Available Protein misfolding disorders such as Alzheimer, Parkinson and transthyretin amyloidosis are characterized by the formation of protein amyloid deposits. Although the nature and location of the aggregated proteins varies between different diseases, they all share similar molecular pathways of protein unfolding, aggregation and amyloid deposition. Most effects of these proteins are likely to occur at the proteome level, a virtually unexplored reality. To investigate the effects of an amyloid protein expression on the cellular proteome, we created a yeast expression system using human transthyretin (TTR as a model amyloidogenic protein. We used Saccharomyces cerevisiae, a living test tube, to express native TTR (non-amyloidogenic and the amyloidogenic TTR variant L55P, the later forming aggregates when expressed in yeast. Differential proteome changes were quantitatively analyzed by 2D-differential in gel electrophoresis (2D-DIGE. We show that the expression of the amyloidogenic TTR-L55P causes a metabolic shift towards energy production, increased superoxide dismutase expression as well as of several molecular chaperones involved in protein refolding. Among these chaperones, members of the HSP70 family and the peptidyl-prolyl-cis-trans isomerase (PPIase were identified. The latter is highly relevant considering that it was previously found to be a TTR interacting partner in the plasma of ATTR patients but not in healthy or asymptomatic subjects. The small ubiquitin-like modifier (SUMO expression is also increased. Our findings suggest that refolding and degradation pathways are activated, causing an increased demand of energetic resources, thus the metabolic shift. Additionally, oxidative stress appears to be a consequence of the amyloidogenic process, posing an enhanced threat to cell survival.

  1. Binary gene induction and protein expression in individual cells

    Directory of Open Access Journals (Sweden)

    Conolly Rory B

    2006-04-01

    Full Text Available Abstract Background Eukaryotic gene transcription is believed to occur in either a binary or a graded fashion. With binary induction, a transcription activator (TA regulates the probability with which a gene template is switched from the inactive to the active state without affecting the rate at which RNA molecules are produced from the template. With graded, also called rheostat-like, induction the gene template has continuously varying levels of transcriptional activity, and the TA regulates the rate of RNA production. Support for each of these two mechanisms arises primarily from experimental studies measuring reporter proteins in individual cells, rather than from direct measurement of induction events at the gene template. Methods and results In this paper, using a computational model of stochastic gene expression, we have studied the biological and experimental conditions under which a binary induction mode operating at the gene template can give rise to differentially expressed "phenotypes" (i.e., binary, hybrid or graded at the protein level. We have also investigated whether the choice of reporter genes plays a significant role in determining the observed protein expression patterns in individual cells, given the diverse properties of commonly-used reporter genes. Our simulation confirmed early findings that the lifetimes of active/inactive promoters and half-lives of downstream mRNA/protein products are important determinants of various protein expression patterns, but showed that the induction time and the sensitivity with which the expressed genes are detected are also important experimental variables. Using parameter conditions representative of reporter genes including green fluorescence protein (GFP and β-galactosidase, we also demonstrated that graded gene expression is more likely to be observed with GFP, a longer-lived protein with low detection sensitivity. Conclusion The choice of reporter genes may determine whether protein

  2. Prolonged morphine administration alters protein expression in the rat myocardium

    OpenAIRE

    Drastichova Zdenka; Skrabalova Jitka; Neckar Jan; Kolar Frantisek; Novotny Jiri

    2011-01-01

    Abstract Background Morphine is used in clinical practice as a highly effective painkiller as well as the drug of choice for treatment of certain heart diseases. However, there is lack of information about its effect on protein expression in the heart. Therefore, here we aimed to identify the presumed alterations in rat myocardial protein levels after prolonged morphine treatment. Methods Morphine was administered to adult male Wistar rats in high doses (10 mg/kg per day) for 10 days. Protein...

  3. Climbazole increases expression of cornified envelope proteins in primary keratinocytes.

    Science.gov (United States)

    Pople, J E; Moore, A E; Talbot, D C S; Barrett, K E; Jones, D A; Lim, F L

    2014-10-01

    Dandruff is a troubling consumer problem characterized by flaking and pruritus of the scalp and is considered a multifactorial condition with sebum, individual susceptibility and the fungus Malassezia all thought to play a part. The condition is commonly treated with shampoo products containing antifungal ingredients such as zinc pyrithione and climbazole. It is hypothesized that these ingredients may be delivering additional scalp skin benefits besides their antifungal activity helping to relieve dandruff effectively. The objective of this study was to evaluate the anti-dandruff ingredient climbazole for potential skin benefits using genomics and in vitro assays. Microarray analysis was performed to profile gene expression changes in climbazole-treated primary human keratinocyte cells. Results were independently validated using qPCR and analysis of protein expression using ELISA and immunocytochemistry. Microarray analysis of climbazole-treated keratinocytes showed statistically significant expression changes in genes associated with the gene ontology groups encompassing epidermal differentiation, keratinization, cholesterol biosynthesis and immune response. Upregulated genes included a number encoding cornified envelope proteins such as group 3 late-cornified envelope proteins, LCE3 and group 2 small-proline-rich proteins, SPRR2. Protein analysis studies of climbazole-treated primary keratinocytes using ELISA and immunocytochemistry were able to demonstrate that the increase in gene transcripts translated into increased protein expression of these cornified envelope markers. Climbazole treatment of primary keratinocytes results in an upregulation in expression of a number of genes including those encoding proteins involved in cornified envelope formation with further studies demonstrating this did translate into increased protein expression. A climbazole-driven increase in cornified envelope proteins may improve the scalp skin barrier, which is known to be weaker

  4. The clinical expression of hereditary protein C and protein S deficiency: : a relation to clinical thrombotic risk-factors and to levels of protein C and protein S

    NARCIS (Netherlands)

    Henkens, C. M. A.; van der Meer, J.; Hillege, J. L.; Bom, V. J. J.; Halie, M. R.; van der Schaaf, W.

    We investigated 103 first-degree relatives of 13 unrelated protein C or protein S deficient patients to assess the role of additional thrombotic risk factors and of protein C and protein S levels in the clinical expression of hereditary protein C and protein S deficiency. Fifty-seven relatives were

  5. Proteomic analysis of Clostridium thermocellum core metabolism: relative protein expression profiles and growth phase-dependent changes in protein expression

    Directory of Open Access Journals (Sweden)

    Rydzak Thomas

    2012-09-01

    Full Text Available Abstract Background Clostridium thermocellum produces H2 and ethanol, as well as CO2, acetate, formate, and lactate, directly from cellulosic biomass. It is therefore an attractive model for biofuel production via consolidated bioprocessing. Optimization of end-product yields and titres is crucial for making biofuel production economically feasible. Relative protein expression profiles may provide targets for metabolic engineering, while understanding changes in protein expression and metabolism in response to carbon limitation, pH, and growth phase may aid in reactor optimization. We performed shotgun 2D-HPLC-MS/MS on closed-batch cellobiose-grown exponential phase C. thermocellum cell-free extracts to determine relative protein expression profiles of core metabolic proteins involved carbohydrate utilization, energy conservation, and end-product synthesis. iTRAQ (isobaric tag for relative and absolute quantitation based protein quantitation was used to determine changes in core metabolic proteins in response to growth phase. Results Relative abundance profiles revealed differential levels of putative enzymes capable of catalyzing parallel pathways. The majority of proteins involved in pyruvate catabolism and end-product synthesis were detected with high abundance, with the exception of aldehyde dehydrogenase, ferredoxin-dependent Ech-type [NiFe]-hydrogenase, and RNF-type NADH:ferredoxin oxidoreductase. Using 4-plex 2D-HPLC-MS/MS, 24% of the 144 core metabolism proteins detected demonstrated moderate changes in expression during transition from exponential to stationary phase. Notably, proteins involved in pyruvate synthesis decreased in stationary phase, whereas proteins involved in glycogen metabolism, pyruvate catabolism, and end-product synthesis increased in stationary phase. Several proteins that may directly dictate end-product synthesis patterns, including pyruvate:ferredoxin oxidoreductases, alcohol dehydrogenases, and a putative

  6. Expression and purification of splicing proteins from mammalian cells.

    Science.gov (United States)

    Allemand, Eric; Hastings, Michelle L

    2014-01-01

    Pre-mRNA splicing is a complex process that is carried out by a large ribonucleoprotein enzyme, termed the spliceosome, which comprises up to 200 proteins. Despite this complexity, the role of individual spliceosomal proteins in the splicing reaction has been successfully investigated using cell-free assays. In many cases, the splicing factor of interest must be expressed and purified in order to study its function in vitro. Posttranslational modifications such as phosphorylation, methylation, acetylation, and ubiquitination of splicing factors are important for activity. Thus, their purification from mammalian cells presents numerous advantages. Here, we describe a method for expression and purification of splicing proteins from mammalian cells.

  7. Protein expression analysis of inflammation-related colon carcinogenesis

    Directory of Open Access Journals (Sweden)

    Yasui Yumiko

    2009-01-01

    Full Text Available Background: Chronic inflammation is a risk factor for colorectal cancer (CRC development. The aim of this study was to determine the differences in protein expression between CRC and the surrounding nontumorous colonic tissues in the mice that received azoxymethane (AOM and dextran sodium sulfate (DSS using a proteomic analysis. Materials and Methods: Male ICR mice were given a single intraperitoneal injection of AOM (10 mg/kg body weight, followed by 2% (w/v DSS in their drinking water for seven days, starting one week after the AOM injection. Colonic adenocarcinoma developed after 20 weeks and a proteomics analysis based on two-dimensional gel electrophoresis and ultraflex TOF/TOF mass spectrometry was conducted in the cancerous and nontumorous tissue specimens. Results: The proteomic analysis revealed 21 differentially expressed proteins in the cancerous tissues in comparison to the nontumorous tissues. There were five markedly increased proteins (beta-tropomyosin, tropomyosin 1 alpha isoform b, S100 calcium binding protein A9, and an unknown protein and 16 markedly decreased proteins (Car1 proteins, selenium-binding protein 1, HMG-CoA synthase, thioredoxin 1, 1 Cys peroxiredoxin protein 2, Fcgbp protein, Cytochrome c oxidase, subunit Va, ETHE1 protein, and 7 unknown proteins. Conclusions: There were 21 differentially expressed proteins in the cancerous tissues of the mice that received AOM and DSS. Their functions include metabolism, the antioxidant system, oxidative stress, mucin production, and inflammation. These findings may provide new insights into the mechanisms of inflammation-related colon carcinogenesis and the establishment of novel therapies and preventative strategies to treat carcinogenesis in the inflamed colon.

  8. Microfluidic chips for protein differential expression profiling.

    Science.gov (United States)

    Armenta, Jenny M; Dawoud, Abdulilah A; Lazar, Iulia M

    2009-04-01

    Biomarker discovery and screening using novel proteomic technologies is an area that is attracting increased attention in the biomedical community. Early detection of abnormal physiological conditions will be highly beneficial for diagnosing various diseases and increasing survivability rates. Clearly, progress in this area will depend on the development of fast, reliable, and highly sensitive and specific sample bioanalysis methods. Microfluidics has emerged as a technology that could become essential in proteomics research as it enables the integration of all sample preparation, separation, and detection steps, with the added benefit of enhanced sample throughput. The combination of these advantages with the sensitivity and capability of MS detection to deliver precise structural information makes microfluidics-MS a very competitive technology for biomarker discovery. The integration of LC microchip devices with MS detection, and specifically their applicability to biomarker screening applications in MCF-7 breast cancer cellular extracts is reported in this manuscript. Loading approximately 0.1-1 microg of crude protein extract tryptic digest on the chip has typically resulted in the reliable identification of approximately 40-100 proteins. The potential of an LC-ESI-MS chip for comparative proteomic analysis of isotopically labeled MCF-7 breast cancer cell extracts is explored for the first time.

  9. Variation in Protein Intake Induces Variation in Spider Silk Expression

    Science.gov (United States)

    Blamires, Sean J.; Wu, Chun-Lin; Tso, I-Min

    2012-01-01

    Background It is energetically expensive to synthesize certain amino acids. The proteins (spidroins) of spider major ampullate (MA) silk, MaSp1 and MaSp2, differ in amino acid composition. Glutamine and proline are prevalent in MaSp2 and are expensive to synthesize. Since most orb web spiders express high proline silk they might preferentially attain the amino acids needed for silk from food and shift toward expressing more MaSp1 in their MA silk when starved. Methodology/Principal Findings We fed three spiders; Argiope aetherea, Cyrtophora moluccensis and Leucauge blanda, high protein, low protein or no protein solutions. A. aetherea and L. blanda MA silks are high in proline, while C. moluccesnsis MA silks are low in proline. After 10 days of feeding we determined the amino acid compositions and mechanical properties of each species' MA silk and compared them between species and treatments with pre-treatment samples, accounting for ancestry. We found that the proline and glutamine of A. aetherea and L. blanda silks were affected by protein intake; significantly decreasing under the low and no protein intake treatments. Glutmaine composition in C. moluccensis silk was likewise affected by protein intake. However, the composition of proline in their MA silk was not significantly affected by protein intake. Conclusions Our results suggest that protein limitation induces a shift toward different silk proteins with lower glutamine and/or proline content. Contradictions to the MaSp model lie in the findings that C. moluccensis MA silks did not experience a significant reduction in proline and A. aetherea did not experience a significant reduction in serine on low/no protein. The mechanical properties of the silks could not be explained by a MaSp1 expressional shift. Factors other than MaSp expression, such as the expression of spidroin-like orthologues, may impact on silk amino acid composition and spinning and glandular processes may impact mechanics. PMID:22363691

  10. Variation in protein intake induces variation in spider silk expression.

    Directory of Open Access Journals (Sweden)

    Sean J Blamires

    Full Text Available BACKGROUND: It is energetically expensive to synthesize certain amino acids. The proteins (spidroins of spider major ampullate (MA silk, MaSp1 and MaSp2, differ in amino acid composition. Glutamine and proline are prevalent in MaSp2 and are expensive to synthesize. Since most orb web spiders express high proline silk they might preferentially attain the amino acids needed for silk from food and shift toward expressing more MaSp1 in their MA silk when starved. METHODOLOGY/PRINCIPAL FINDINGS: We fed three spiders; Argiope aetherea, Cyrtophora moluccensis and Leucauge blanda, high protein, low protein or no protein solutions. A. aetherea and L. blanda MA silks are high in proline, while C. moluccesnsis MA silks are low in proline. After 10 days of feeding we determined the amino acid compositions and mechanical properties of each species' MA silk and compared them between species and treatments with pre-treatment samples, accounting for ancestry. We found that the proline and glutamine of A. aetherea and L. blanda silks were affected by protein intake; significantly decreasing under the low and no protein intake treatments. Glutmaine composition in C. moluccensis silk was likewise affected by protein intake. However, the composition of proline in their MA silk was not significantly affected by protein intake. CONCLUSIONS: Our results suggest that protein limitation induces a shift toward different silk proteins with lower glutamine and/or proline content. Contradictions to the MaSp model lie in the findings that C. moluccensis MA silks did not experience a significant reduction in proline and A. aetherea did not experience a significant reduction in serine on low/no protein. The mechanical properties of the silks could not be explained by a MaSp1 expressional shift. Factors other than MaSp expression, such as the expression of spidroin-like orthologues, may impact on silk amino acid composition and spinning and glandular processes may impact

  11. Differential Protein Expression in Congenital and Acquired Cholesteatomas.

    Directory of Open Access Journals (Sweden)

    Seung-Ho Shin

    Full Text Available Congenital cholesteatomas are epithelial lesions that present as an epithelial pearl behind an intact eardrum. Congenital and acquired cholesteatomas progress quite differently from each other and progress patterns can provide clues about the unique origin and pathogenesis of the abnormality. However, the exact pathogenic mechanisms by which cholesteatomas develop remain unknown. In this study, key proteins that directly affect cholesteatoma pathogenesis are investigated with proteomics and immunohistochemistry. Congenital cholesteatoma matrices and retroauricular skin were harvested during surgery in 4 patients diagnosed with a congenital cholesteatoma. Tissue was also harvested from the retraction pocket in an additional 2 patients during middle ear surgery. We performed 2-dimensional (2D electrophoresis to detect and analyze spots that are expressed only in congenital cholesteatoma and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/MS to separate proteins by molecular weight. Protein expression was confirmed by immunohistochemical staining. The image analysis of 2D electrophoresis showed that 4 congenital cholesteatoma samples had very similar protein expression patterns and that 127 spots were exclusively expressed in congenital cholesteatomas. Of these 127 spots, 10 major spots revealed the presence of titin, forkhead transcription activator homolog (FKH 5-3, plectin 1, keratin 10, and leucine zipper protein 5 by MALDI-TOF/MS analysis. Immunohistochemical staining showed that FKH 5-3 and titin were expressed in congenital cholesteatoma matrices, but not in acquired cholesteatomas. Our study shows that protein expression patterns are completely different in congenital cholesteatomas, acquired cholesteatomas, and skin. Moreover, non-epithelial proteins, including FKH 5-3 and titin, were unexpectedly expressed in congenital cholesteatoma tissue. Our data indicates that congenital cholesteatoma origins

  12. Identification of Differentially Expressed Serum Proteins in Infectious Purpura Fulminans

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    Ting He

    2014-01-01

    Full Text Available Purpura fulminans (PF is a life-threatening hemorrhagic condition. Because of the rarity and randomness of the disease, no improvement in treatment has been made for a long time. In this study, we assessed the serum proteome response to PF by comparing serum proteins between healthy controls and PF patient. Liquid chromatography with tandem mass spectrometry (LC-MS/MS approach was used after depleting 6 abundant proteins of serum. In total, 262 proteins were confidently identified with 2 unique peptides, and 38 proteins were identified significantly up- (≥2 or downregulated (≤0.5 based on spectral counting ratios (SpCPF/N. In the 38 proteins with significant abundance changes, 11 proteins were previously known to be associated with burn or sepsis response, but 27 potentially novel proteins may be specifically associated with PF process. Two differentially expressed proteins, alpha-1-antitrypsin (SERPINA1 and alpha-2 antiplasmin (SERPINF2, were validated by Western blot. This is the first study where PF patient and healthy controls are compared in a proteomic study to elucidate proteins involved in the response to PF. This study provides an initial basis for future studies of PF, and the differentially expressed proteins might provide new therapeutic targets to decrease the mortality of PF.

  13. Translational Modulation of Proteins Expressed from Bicistronic Vectors

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    Prasun J. Mishra

    2009-11-01

    Full Text Available Bicistronic vectors are useful tools for exogenous expression of two gene products from a single promoter element; however, reduced expression of protein from the second cistron compared with the first cistron is a common limitation to this approach. To overcome this limitation, we explored use of dihydrofolate reductase (DHFR complementary DNA encoded in bicistronic vectors to induce a second protein of interest by methotrexate (MTX treatment. Previous studies have demonstrated that levels of DHFR protein and DHFR fusion protein can be induced translationally following MTX treatment of cells. We demonstrated that in response to MTX treatment, DHFR partner protein in a bicistronic construct is induced for longer periods of time when compared with endogenous DHFR and DHFR fusion protein, in vitro and in vivo. Using rapamycin pretreatment followed by MTX treatment, we also devised a strategy to modulate levels of two proteins expressed from a bicistronic construct in a cap-independent manner. To our knowledge, this is the first report demonstrating that levels of proteins in DHFR-based bicistronic constructs can be induced and modulated using MTX and rapamycin treatment.

  14. Prolonged morphine administration alters protein expression in the rat myocardium

    Directory of Open Access Journals (Sweden)

    Drastichova Zdenka

    2011-11-01

    Full Text Available Abstract Background Morphine is used in clinical practice as a highly effective painkiller as well as the drug of choice for treatment of certain heart diseases. However, there is lack of information about its effect on protein expression in the heart. Therefore, here we aimed to identify the presumed alterations in rat myocardial protein levels after prolonged morphine treatment. Methods Morphine was administered to adult male Wistar rats in high doses (10 mg/kg per day for 10 days. Proteins from the plasma membrane- and mitochondria-enriched fractions or cytosolic proteins isolated from left ventricles were run on 2D gel electrophoresis, scanned and quantified with specific software to reveal differentially expressed proteins. Results Nine proteins were found to show markedly altered expression levels in samples from morphine-treaded rats and these proteins were identified by mass spectrometric analysis. They belong to different cell pathways including signaling, cytoprotective, and structural elements. Conclusions The present identification of several important myocardial proteins altered by prolonged morphine treatment points to global effects of this drug on heart tissue. These findings represent an initial step toward a more complex view on the action of morphine on the heart.

  15. Construction, Expression and Purification of SUMO1-GST Fusion Protein

    Institute of Scientific and Technical Information of China (English)

    QIAO Xiao-fang; FANG Xue-dong; LIU Jun

    2011-01-01

    Sumoylation is an important protein modification discovered recently. SUMO(small ubiquitin-related modifier) pathway regulates the protein stability and transcriptional activity with a 12-kDa small molecular protein,SUMO, ligated to the target protein. The purification of SUMO proteins is a key step to reveal their function. The purpose of this study was to construct the recombinant SUMO1 gene cloned to a pGEX-4T-1 vector to express and purify the SUMO1-GST fusion protein in Escherichia coli. First, the full length DNA sequence of SUMO1 gene was amplified by PCR and was ligated to pMD18-T vector. Then the SUMO1 gene was subcloned to pGEX-4T-1 prokaryotic expression vector between BamHI and XhoI sites, and transformed in Escherichia coli DH5a cells. The right colonies were identified by restrictive enzyme digestion and sequencing. The correct rebombinant plasmid of pGEX-4T-1-SUMO1 was transformed in Escherichia coli BL21 cells and then induced by IPTG(isopropyl-β-D-lthiogalacto-pyranoside) to express the SUMO1-GST fusion protein. The highly purified SUMOl-GST(glutathione S-transferase) fusion protein was obtained by affinity chromatography. Finally, the properties of SUMO1-GST fusion protein were confirmed by Coomassie brilliant blue strain and Western blot analysis. The recombinant plasmid of pGEX-4T-1-SUMO 1 was successfully constructed, and SUMO1-GST fusion proteins were successfully expressed.

  16. Expression of genes encoding extracellular matrix proteins: a macroarray study.

    Science.gov (United States)

    Futyma, Konrad; Miotła, Paweł; Różyńska, Krystyna; Zdunek, Małgorzata; Semczuk, Andrzej; Rechberger, Tomasz; Wojcierowski, Jacek

    2014-12-01

    Endometrial cancer (EC) is one of the most common gynecological malignancies in Poland, with well-established risk factors. Genetic instability and molecular alterations responsible for endometrial carcinogenesis have been systematically investigated. The aim of the present study was to investigate, by means of cDNA macroarrays, the expression profiles of genes encoding extracellular matrix (ECM) proteins in ECs. Tissue specimens were collected during surgical procedures from 40 patients with EC, and control tissue was collected from 9 patients with uterine leiomyomas. RNA was isolated and RT-PCR with radioisotope-labeled cDNA was performed. The levels of ECM protein gene expression in normal endometrial tissues were compared to the expression of these genes in EC specimens. Statistically significant differences in gene expression, stratified by clinical stage of the ECs, were detected for aggrecan, vitronectin, tenascin R, nidogen and two collagen proteins: type VIII chain α1 and type XI chain α2. All of these proteins were overexpressed in stage III endometrial carcinomas compared to levels in stage I and II uterine neoplasms. In conclusion, increased expression of genes encoding ECM proteins may play an important role in facilitating accelerated disease progression of human ECs.

  17. Expression of SKP2 Protein in Lung Carcinoma

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jun; YANG Chun-lu; ZHANG Huan; DING Wei-zhong; LIU Zhi-ping; LIU Jing-yi

    2008-01-01

    Objective:To study the expressive characteristics of SKP2 protein in lung carcinoma and its implication for prognosis.Methods:The expression of SKP2 protein was detected in 89 non small cell lung carcinoma,13 small cell lung carcinoma,10 lung benign lesion tissues by Tissue Chip and Immunohistochemistry technology.Results:The positive rate of SKP2 protein staining was(23.52±13.57)% in non small cell lung carcinoma and (53.85+12.26)% in small cell lung carcinoma,which were significantly higher than(2.91±1.27)% in lung benign lesion tissues.It was highest in small cell lung carcinoma and lowest in lung benign lesion tissues,with a significant difference between them(P=0.000).The expressive level of SKP2 protein in lung carcinoma tissues was closely related to cell differentiation,lymph node metastasis and pathological types,but not to age,sex,smoking history,tumor site and size,and TNM staging.The survival analysis revealed that the 5-year survival rate of lung carcinoma patients was lower in SKP2 protein positive expression group than that in negative expression group(P1=0.003/0.002;r=-0.275,P2=0.005).Conclusion:The positive expression of SKP2 protein is higher in lung carcinoma than in lung benign lesion tissues.in particular,much higher in small cell lung carcinoma.In lung carcinoma,its expressive level was closely related to cell differentiation,lymph node metastasis and pathological types.Moreover,it may be an independent factor to prognosis of patients with lung carcinoma.

  18. EXPRESSION AND SIGNIFICANCE OF ERK PROTEIN IN HUMAN BREAST CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    张秀梅; 李柏林; 宋敏; 宋继谒

    2004-01-01

    Objective: To investigate the expression of ERK and p-ERK protein in human breast cancer and their corresponding tissue, to assess the significance of ERK signal pathway in tumorigenesis and progression of breast carcinoma. Methods: 40 breast cancer cases were used in S-P immunohistochemistry technique and Western Blot study. Results: The expression of ERK1, ERK2, and p- ERK protein levels increased remarkably in breast cancer tissues in comparison to normal tissues (P<0.01). The expression was upregulated by 1.32-, 1.53-and 4.27-fold, respectively. The overexpressions of ERK1, ERK2, and p- ERK proteins were obviously correlated with clinical stage of breast cancer. Protein levels of ERK and p-ERK were higher in stage III patients than in stage I and stage II patients (P<0.05). These proteins were strongly related with axillary lymph node metastasis of breast cancer, but not correlated with histopathological type and status of ER and PR of breast cancer. Expression of ERK1, and ERK2, protein showed a positive linear correlation. Conclusion: ERK signal transduction pathway is a key factor during human breast tumorigenesis and breast cancer progression.

  19. Expression of Extracellular Superoxide Dismutase Protein in Diabetes

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    Chul Han Kim

    2013-09-01

    Full Text Available Background Diabetes is characterized by chronic hyperglycemia, which can increase reactiveoxygen species (ROS production by the mitochondrial electron transport chain. The formationof ROS induces oxidative stress and activates oxidative damage-inducing genes in cells. Noresearch has been published on oxidative damage-related extracellular superoxide dismutase(EC-SOD protein levels in human diabetic skin. We investigated the expression of EC-SOD indiabetic skin compared with normal skin tissue in vivo.Methods The expression of EC-SOD protein was evaluated by western blotting in 6 diabeticskin tissue samples and 6 normal skin samples. Immunohistochemical staining was also carriedout to confirm the EC-SOD expression level in the 6 diabetic skin tissue samples.Results The western blotting showed significantly lower EC-SOD protein expression in thediabetic skin tissue than in the normal tissue. Immunohistochemical examination of EC-SODprotein expression supported the western blotting analysis.Conclusions Diabetic skin tissues express a relatively small amount of EC-SOD protein andmay not be protected against oxidative stress. We believe that EC-SOD is related to the alteredmetabolic state in diabetic skin, which elevates ROS production.

  20. Raf-1 kinase inhibitory protein expression in thyroid carcinomas.

    Science.gov (United States)

    Kim, Hyun-Soo; Kim, Gou Young; Lim, Sung-Jig; Kim, Youn Wha

    2010-12-01

    Raf-1 kinase inhibitory protein (RKIP) has been implicated in several fundamental signal transduction pathways that control cellular growth, differentiation, apoptosis and migration. RKIP is reduced in a variety of human carcinomas, but RKIP expression in thyroid carcinomas has not been analyzed at the protein level. In this study, we examined the immunohistochemical expression of RKIP in various subtypes of thyroid carcinoma. Immunostaining for RKIP was performed on 104 cases of primary thyroid carcinoma (40 papillary, 29 follicular, 11 medullary, 11 poorly differentiated, and 13 anaplastic carcinomas) and 26 cases of nodal metastatic tumor (17 papillary, 4 medullary, and 5 anaplastic carcinomas). Normal thyroid tissue and all cases of follicular, papillary, and medullary carcinomas showed uniform, strong cytoplasmic immunoreactivity for RKIP. With the exception of one case, poorly differentiated carcinomas also revealed strong RKIP expression. In contrast, RKIP expression was completely absent in all anaplastic carcinomas. The transition zone from the differentiated carcinoma component (strong RKIP expression) to the anaplastic carcinoma component (no RKIP expression) demonstrated a completely opposite pattern of RKIP immunoreactivity. This reduction of RKIP expression in anaplastic carcinoma was statistically significant (P carcinomas showed uniform, strong cytoplasmic RKIP immunoreactivity, in contrast, in metastatic anaplastic carcinomas, RKIP expression was completely absent. RKIP expression is significantly reduced in anaplastic thyroid carcinoma as compared to other subtypes of thyroid carcinoma. Further studies are necessary to elucidate the precise mechanism of RKIP action in anaplastic thyroid carcinoma.

  1. Expression and biochemical characterization of recombinant human epididymis protein 4.

    Science.gov (United States)

    Hua, Ling; Liu, Yunhui; Zhen, Shuai; Wan, Deyou; Cao, Jiyue; Gao, Xin

    2014-10-01

    Whey acidic proteins (WAP) belong to a large gene family of antibacterial peptides that perform critical immune system functions. The function of human epididymis protein 4 (HE4), a 124-amino acid long polypeptide that has two whey acidic protein four-disulfide core (WFDC) domains, is not well studied. Here, a fusion gene encoding the HE4 protein fused to an IgG1 Fc domain was constructed. The recombinant HE4 protein was expressed as a secretory protein in Pichia pastoris and mammalian HEK293-F cells and was subsequently purified. Our data suggested that the HE4 protein produced by these two expression systems bound to both gram-negative and gram-positive bacteria, but demonstrated slightly inhibitory activity towards the growth of Staphylococcus aureus. Moreover, HE4 exhibited proteinase inhibitory activity towards trypsin, elastase, matrix metallopeptidase 9, and the secretory proteinases from Bacillus subtilis. The effects of glycosylation on the biochemical characterization of HE4 were also investigated. LC-ESI-MS glycosylation analysis showed that the high-mannose glycosylated form of HE4 expressed by P. pastoris has lower biological activity when compared to its complex-glycosylated form produced from HEK293-F cells. The implications of this are discussed, which may be provide theoretical basis for its important role in the development of cancer and innate immune system.

  2. Expression of Structural Protein E2 of Hepatitis C Virus

    Institute of Scientific and Technical Information of China (English)

    GUO Tai-lin; YE Lin-bo; MAO Can-quan

    2005-01-01

    The E2 glycoprotein is one of the structural components of the hepatitis C virus (HCV) virion. It elicits production of neutralising antibodies against the virus, and is involved in viral morphogenesis. The protein is considered as a major candidate for anti- HCV vaccine. Despitethis, little is known about this protein. Previous studies have focused on the and functional analysis of the glycosylated forms. This report describes expression of the E2 (recE2) in different forms and in different expression systems in Escherichia coli cells and in mammalian cells in order to obtain enough protein efficiently in vitro, in addition we also analysed the usage of rare codons in the genes of E2 and CORE. All results have shown that great efforts should be made to improve the expression efficiency of E2 in bacteria or mammalian cells.

  3. Expression and Purification of SARS Coronavirus Membrane Protein

    Institute of Scientific and Technical Information of China (English)

    戴五星; 雷明军; 吴少庭; 陈智浩; 梁靓; 潘晖榕; 秦莉; 高士同; 袁仕善; 张仁利

    2004-01-01

    To construct a recombinant plasmid Pet23a-M, the gene encoding severe acute respiratory syndrome (SARS) coronavirus membrane protein was amplified by RT-PCR and cloned into the expression plasmid Pet23a. Results of restriction endonuclease analysis, PCR detection and DNA sequencing analysis revealed that the cloned DNA sequence was the same as that reported. The re combinants were transformed into Escherichia coli (E. Coli) BL21 (DE3) and induced by Isopropylβ-D-thiogalactopyranoside (IPTG). The expression of 27 kD (1 kD=0. 992 1 ku) protein was detected by SDS-PAGE and pured by metal chelated chromatography. Results of Western-blot showed that this expressed protein could react with antibodies in sera of SARS patients during convalescence. This provided the basis for the further study on SARS virus vaccine and diagnostic agents.

  4. Expression of protein-coding genes embedded in ribosomal DNA

    DEFF Research Database (Denmark)

    Johansen, Steinar D; Haugen, Peik; Nielsen, Henrik

    2007-01-01

    Ribosomal DNA (rDNA) is a specialised chromosomal location that is dedicated to high-level transcription of ribosomal RNA genes. Interestingly, rDNAs are frequently interrupted by parasitic elements, some of which carry protein genes. These are non-LTR retrotransposons and group II introns...... that encode reverse transcriptase-like genes, and group I introns and archaeal introns that encode homing endonuclease genes (HEGs). Although rDNA-embedded protein genes are widespread in nuclei, organelles and bacteria, there is surprisingly little information available on how these genes are expressed....... Exceptions include a handful of HEGs from group I introns. Recent studies have revealed unusual and essential roles of group I and group I-like ribozymes in the endogenous expression of HEGs. Here we discuss general aspects of rDNA-embedded protein genes and focus on HEG expression from group I introns...

  5. Using ion exchange chromatography to purify a recombinantly expressed protein.

    Science.gov (United States)

    Duong-Ly, Krisna C; Gabelli, Sandra B

    2014-01-01

    Ion exchange chromatography (IEX) separates molecules by their surface charge, a property that can vary vastly between different proteins. There are two types of IEX, cation exhange and anion exchange chromatography. The protocol that follows was designed by the authors for anion exchange chromatography of a recombinantly expressed protein having a pI of 4.9 and containing two cysteine residues and one tryptophan residue, using an FPLC system. Prior to anion exchange, the protein had been salted out using ammonium sulfate precipitation and partially purified via hydrophobic interaction chromatography (see Salting out of proteins using ammonium sulfate precipitation and Use and Application of Hydrophobic Interaction Chromatography for Protein Purification). Slight modifications to this protocol may be made to accommodate both the protein of interest and the availability of equipment.

  6. The expression and significance of p53 protein and Ki-67 protein in pterygium

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    Ljubojević Vesna

    2016-01-01

    Full Text Available Background/Aim. Pterygium is considered to be a degenerative disease of the conjunctiva, however, the presence of tumor markers in pterygium reinforces the hypothesis that this lesion is similar to tumor. Inactivation of p53 function removes an obstacle to increased proliferation. Factors affecting the prevalence of p53 expression in pterygium deserve investigation. The aim of the study was to investigate the expression of p53 and Ki-67 proteins in pterygium and normal conjunctiva, the effects of gender and age on p53 expression, and the relationship between the expression of p53 and Ki-67 proteins. Methods. A total of 34 samples of pterygium and 34 samples of the normal conjunctiva were analyzed. The samples were studied by immunohistochemistry using antibodies against p53 and Ki-67. Results. Totally 15 (44% samples of pterygia were p53 positive. Correlations between the expression of p53 protein and sex, and age were not established. The number of Ki-67 positive cells in pterygium (9.74% was significantly higher than the number of Ki-67 positive cells in the normal conjunctiva (1.74%, (p = 0.001. Between the expression of p53 protein and Ki-67 protein in pterygium there was a significant positive correlation (p = 0.000. Conclusion. The prevalence of p53 positive samples of pterygium was 44%. The influence of sex and age on p53 protein expression in pterygium was not found. The increased proliferative acivity was present in the epithelium of pterygium. The expression of Ki-67 protein is associated with the expression of p53 protein in pterygium. The findings of our study support the thesis of pterygium as tissue growth disorder.

  7. Express your LOV: an engineered flavoprotein as a reporter for protein expression and purification.

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    Jayde A Gawthorne

    Full Text Available In this work, we describe the utility of Light, Oxygen, or Voltage-sensing (LOV flavoprotein domains from plant phototropins as a reporter for protein expression and function. Specifically, we used iLOV, an enhanced and more photostable variant of LOV. A pET-based plasmid for protein expression was constructed, encoding a C terminal iLOV-octahistidine (His8-tag and a HRV 3C protease cleavage recognition site. Ten different proteins, with various sub-cellular locations, were cloned into the plasmid, creating iLOV-His8 tag fusions. To test protein expression and how iLOV could be used as a reporter, the proteins were expressed in three different cell lines, in four different culture media, at two different temperatures. To establish whether the presence of the iLOV tag could have an impact on the functionality, one of the proteins, EspG, was over-expressed and purified. EspG is an "effector" protein normally produced by enterohemorrhagic E. coli strains and "injected" into host cells via the T3SS. We tested functionality of EspG-iLOV fusion by performing functional studies of EspG in mammalian host cells. When EspG-iLOV was microinjected into the host cell, the Golgi apparatus was completely disrupted as had previously been observed for EspG.

  8. SPINK 1 Protein Expression and Prostate Cancer Progression

    Science.gov (United States)

    Flavin, Richard; Pettersson, Andreas; Hendrickson, Whitney K.; Fiorentino, Michelangelo; Finn, Stephen; Kunz, Lauren; Judson, Gregory L.; Lis, Rosina; Bailey, Dyane; Fiore, Christopher; Nuttall, Elizabeth; Martin, Neil E.; Stack, Edward; Penney, Kathryn L.; Rider, Jennifer R.; Sinnott, Jennifer; Sweeney, Christopher; Sesso, Howard D.; Fall, Katja; Giovannucci, Edward; Kantoff, Philip; Stampfer, Meir; Loda, Massimo; Mucci, Lorelei A.

    2014-01-01

    Purpose SPINK1 over-expression has been described in prostate cancer and is linked with poor prognosis in many cancers. The objective of this study was to characterize the association between SPINK1 over-expression and prostate cancer specific survival. Experimental Design The study included 879 participants in the US Physicians’ Health Study and Health Professionals Follow–Up Study, diagnosed with prostate cancer (1983 – 2004) and treated by radical prostatectomy. Protein tumor expression of SPINK1 was evaluated by immunohistochemistry on tumor tissue microarrays. Results 74/879 (8%) prostate cancer tumors were SPINK1 positive. Immunohistochemical data was available for PTEN, p-Akt, pS6, stathmin, androgen receptor (AR) and ERG (as a measure of the TMPRSS2:ERG translocation). Compared to SPINK1 negative tumors, SPINK1 positive tumors showed higher PTEN and stathmin expression, and lower expression of AR (p<0.01). SPINK1 over-expression was seen in 47 of 427 (11%) ERG negative samples and in 19 of 427 (4%) ERG positive cases (p=0.0003). We found no significant associations between SPINK1 status and Gleason grade or tumor stage. There was no association between SPINK1 expression and biochemical recurrence (p=0.56). Moreover, there was no association between SPINK1 expression and prostate cancer mortality (there were 75 lethal cases of prostate cancer during a mean of 13.5 years follow-up [HR 0.71 (95% confidence interval 0.29–1.76)]). Conclusions Our results suggest that SPINK1 protein expression may not be a predictor of recurrence or lethal prostate cancer amongst men treated by radical prostatectomy. SPINK1 and ERG protein expression do not appear to be entirely mutually exclusive, as some previous studies have suggested. PMID:24687926

  9. Expression and export: recombinant protein production systems for Aspergillus.

    Science.gov (United States)

    Fleissner, André; Dersch, Petra

    2010-07-01

    Several Aspergillus species, in particular Aspergillus niger and Aspergillus oryzae, are widely used as protein production hosts in various biotechnological applications. In order to improve the expression and secretion of recombinant proteins in these filamentous fungi, several novel genetic engineering strategies have been developed in recent years. This review describes state-of-the-art genetic manipulation technologies used for strain improvement, as well as recent advances in designing the most appropriate engineering strategy for a particular protein production process. Furthermore, current developments in identifying bottlenecks in the protein production and secretion pathways are described and novel approaches to overcome these limitations are introduced. An appropriate combination of expression vectors and optimized host strains will provide cell factories customized for each production process and expand the great potential of Aspergilli as biotechnology workhorses to more complex multi-step industrial applications.

  10. Decreased Expression of GPER1 Gene and Protein in Goiter

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    Raquel Weber

    2015-01-01

    Full Text Available Goiter is more common in women, suggesting that estrogen could be involved in its physiopathology. The presence of classical estrogen receptors (ERα and ERβ has been described in thyroid tissue, suggesting a direct effect of estrogen on the gland. A nonclassic estrogen receptor, the G-protein-coupled estrogen receptor (GPER1, has been described recently in several tissues. However, in goiter, the presence of this receptor has not been studied yet. We investigated GPER1 gene and protein expressions in normal thyroid and goiter using reverse transcription quantitative polymerase chain reaction (RT-qPCR and Western blot, respectively. In normal thyroid (n=16 and goiter (n=19, GPER1 gene was expressed in all samples, while GPER1 protein was expressed in all samples of normal thyroid (n=15 but in only 72% of goiter samples (n=13. When comparing GPER1 gene and protein levels in both conditions, gene expression and protein levels were higher in normal thyroid than in goiter, suggesting a role of this receptor in this condition. Further studies are needed to elucidate the role of GPER1 in normal thyroid and goiter.

  11. p53 and MDM2 protein expression in actinic cheilitis.

    Science.gov (United States)

    de Freitas, Maria da Conceição Andrade; Ramalho, Luciana Maria Pedreira; Xavier, Flávia Caló Aquino; Moreira, André Luis Gomes; Reis, Sílvia Regina Almeida

    2008-01-01

    Actinic cheilitis is a potentially malignant lip lesion caused by excessive and prolonged exposure to ultraviolet radiation, which can lead to histomorphological alterations indicative of abnormal cell differentiation. In this pathology, varying degrees of epithelial dysplasia may be found. There are few published studies regarding the p53 and MDM2 proteins in actinic cheilitis. Fifty-eight cases diagnosed with actinic cheilitis were histologically evaluated using Banóczy and Csiba (1976) parameters, and were subjected to immunohistochemical analysis using the streptavidin-biotin method in order to assess p53 and MDM2 protein expression. All studied cases expressed p53 proteins in basal and suprabasal layers. In the basal layer, the nuclei testing positive for p53 were stained intensely, while in the suprabasal layer, cells with slightly stained nuclei were predominant. All cases also tested positive for the MDM2 protein, but with varying degrees of nuclear expression and a predominance of slightly stained cells. A statistically significant correlation between the percentage of p53 and MDM2-positive cells was established, regardless of the degree of epithelial dysplasia. The expression of p53 and MDM2 proteins in actinic cheilitis can be an important indicator in lip carcinogenesis, regardless of the degree of epithelial dysplasia.

  12. p53 and MDM2 protein expression in actinic cheilitis

    Directory of Open Access Journals (Sweden)

    Maria da Conceição Andrade de Freitas

    2008-12-01

    Full Text Available Actinic cheilitis is a potentially malignant lip lesion caused by excessive and prolonged exposure to ultraviolet radiation, which can lead to histomorphological alterations indicative of abnormal cell differentiation. In this pathology, varying degrees of epithelial dysplasia may be found. There are few published studies regarding the p53 and MDM2 proteins in actinic cheilitis. Fifty-eight cases diagnosed with actinic cheilitis were histologically evaluated using Banóczy and Csiba (1976 parameters, and were subjected to immunohistochemical analysis using the streptavidin-biotin method in order to assess p53 and MDM2 protein expression. All studied cases expressed p53 proteins in basal and suprabasal layers. In the basal layer, the nuclei testing positive for p53 were stained intensely, while in the suprabasal layer, cells with slightly stained nuclei were predominant. All cases also tested positive for the MDM2 protein, but with varying degrees of nuclear expression and a predominance of slightly stained cells. A statistically significant correlation between the percentage of p53 and MDM2-positive cells was established, regardless of the degree of epithelial dysplasia. The expression of p53 and MDM2 proteins in actinic cheilitis can be an important indicator in lip carcinogenesis, regardless of the degree of epithelial dysplasia.

  13. Interfacial polymerization for colorimetric labeling of protein expression in cells.

    Directory of Open Access Journals (Sweden)

    Jacob L Lilly

    Full Text Available Determining the location of rare proteins in cells typically requires the use of on-sample amplification. Antibody based recognition and enzymatic amplification is used to produce large amounts of visible label at the site of protein expression, but these techniques suffer from the presence of nonspecific reactivity in the biological sample and from poor spatial control over the label. Polymerization based amplification is a recently developed alternative means of creating an on-sample amplification for fluorescence applications, while not suffering from endogenous labels or loss of signal localization. This manuscript builds upon polymerization based amplification by developing a stable, archivable, and colorimetric mode of amplification termed Polymer Dye Labeling. The basic concept involves an interfacial polymer grown at the site of protein expression and subsequent staining of this polymer with an appropriate dye. The dyes Evans Blue and eosin were initially investigated for colorimetric response in a microarray setting, where both specifically stained polymer films on glass. The process was translated to the staining of protein expression in human dermal fibroblast cells, and Polymer Dye Labeling was specific to regions consistent with desired protein expression. The labeling is stable for over 200 days in ambient conditions and is also compatible with modern mounting medium.

  14. Interfacial polymerization for colorimetric labeling of protein expression in cells.

    Science.gov (United States)

    Lilly, Jacob L; Sheldon, Phillip R; Hoversten, Liv J; Romero, Gabriela; Balasubramaniam, Vivek; Berron, Brad J

    2014-01-01

    Determining the location of rare proteins in cells typically requires the use of on-sample amplification. Antibody based recognition and enzymatic amplification is used to produce large amounts of visible label at the site of protein expression, but these techniques suffer from the presence of nonspecific reactivity in the biological sample and from poor spatial control over the label. Polymerization based amplification is a recently developed alternative means of creating an on-sample amplification for fluorescence applications, while not suffering from endogenous labels or loss of signal localization. This manuscript builds upon polymerization based amplification by developing a stable, archivable, and colorimetric mode of amplification termed Polymer Dye Labeling. The basic concept involves an interfacial polymer grown at the site of protein expression and subsequent staining of this polymer with an appropriate dye. The dyes Evans Blue and eosin were initially investigated for colorimetric response in a microarray setting, where both specifically stained polymer films on glass. The process was translated to the staining of protein expression in human dermal fibroblast cells, and Polymer Dye Labeling was specific to regions consistent with desired protein expression. The labeling is stable for over 200 days in ambient conditions and is also compatible with modern mounting medium.

  15. Recombinant protein expression by targeting pre-selected chromosomal loci

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    Krömer Wolfgang

    2009-12-01

    Full Text Available Abstract Background Recombinant protein expression in mammalian cells is mostly achieved by stable integration of transgenes into the chromosomal DNA of established cell lines. The chromosomal surroundings have strong influences on the expression of transgenes. The exploitation of defined loci by targeting expression constructs with different regulatory elements is an approach to design high level expression systems. Further, this allows to evaluate the impact of chromosomal surroundings on distinct vector constructs. Results We explored antibody expression upon targeting diverse expression constructs into previously tagged loci in CHO-K1 and HEK293 cells that exhibit high reporter gene expression. These loci were selected by random transfer of reporter cassettes and subsequent screening. Both, retroviral infection and plasmid transfection with eGFP or antibody expression cassettes were employed for tagging. The tagged cell clones were screened for expression and single copy integration. Cell clones producing > 20 pg/cell in 24 hours could be identified. Selected integration sites that had been flanked with heterologous recombinase target sites (FRTs were targeted by Flp recombinase mediated cassette exchange (RMCE. The results give proof of principle for consistent protein expression upon RMCE. Upon targeting antibody expression cassettes 90-100% of all resulting cell clones showed correct integration. Antibody production was found to be highly consistent within the individual cell clones as expected from their isogenic nature. However, the nature and orientation of expression control elements revealed to be critical. The impact of different promoters was examined with the tag-and-targeting approach. For each of the chosen promoters high expression sites were identified. However, each site supported the chosen promoters to a different extent, indicating that the strength of a particular promoter is dominantly defined by its chromosomal context

  16. hTERT protein expression is independent of clinicopathological parameters and c-Myc protein expression in human breast cancer

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    Meligonis G

    2005-01-01

    Full Text Available Abstract Background Telomerase is a ribonucleoprotein enzyme that synthesises telomeres after cell division and maintains chromosomal length and stability thus leading to cellular immortalisation. The hTERT (human telomerase reverse transcriptase subunit seems to be the rate-limiting determinant of telomerase and knowledge of factors controlling hTERT transcription may be useful in therapeutic strategies. The hTERT promoter contains binding sites for c-Myc and there is some experimental and in vitro evidence that c-Myc may increase hTERT expression. We previously reported no correlation between c-Myc mRNA expression and hTERT mRNA or telomerase activity in human breast cancer. This study aims to examine the correlation between hTERT expression as determined by immunohistochemistry and c-Myc expression, lymph node status, and tumour size and grade in human breast cancer. Materials and methods The immunohistochemical expression of hTERT and c-Myc was investigated in 38 malignant breast tumours. The expression of hTERT was then correlated with the lymph node status, c-Myc expression and other clinicopathological parameters of the tumours. Results hTERT expression was positive in 27 (71% of the 38 tumours. 15 (79% of 19 node positive tumours were hTERT positive compared with 11 (63% of 19 node negative tumours. The expression was higher in node positive tumours but this failed to reach statistical significance (p = 0.388. There was no significant association with tumour size, tumour grade or c-Myc expression. However, hTERT expression correlated positively with patients' age (correlation coefficient = 0.415, p = 0.0097. Conclusion hTERT protein expression is independent of lymph node status, tumour size and grade and c-Myc protein expression in human breast cancer

  17. Fragile X mental retardation protein (FMRP) interacting proteins exhibit different expression patterns during development.

    Science.gov (United States)

    Bonaccorso, C M; Spatuzza, M; Di Marco, B; Gloria, A; Barrancotto, G; Cupo, A; Musumeci, S A; D'Antoni, S; Bardoni, B; Catania, M V

    2015-05-01

    Fragile X syndrome is caused by the lack of expression of fragile X mental retardation protein (FMRP), an RNA-binding protein involved in mRNA transport and translation. FMRP is a component of mRNA ribonucleoprotein complexes and it can interact with a range of proteins either directly or indirectly, as demonstrated by two-hybrid selection and co-immunoprecipitation, respectively. Most of FMRP-interacting proteins are RNA-binding proteins such as FXR1P, FXR2P and 82-FIP. Interestingly, FMRP can also interact directly with the cytoplasmic proteins CYFIP1 and CYFIP2, which do not bind RNA and link FMRP to the RhoGTPase pathway. The interaction with these different proteins may modulate the functions of FMRP by influencing its affinity to RNA and by affecting the FMRP ability of cytoskeleton remodeling through Rho/Rac GTPases. To better define the relationship of FMRP with its interacting proteins during brain development, we have analyzed the expression pattern of FMRP and its interacting proteins in the cortex, striatum, hippocampus and cerebellum at different ages in wild type (WT) mice. FMRP and FXR2P were strongly expressed during the first week and gradually decreased thereafter, more rapidly in the cerebellum than in the cortex. FXR1P was also expressed early and showed a reduction at later stages of development with a similar developmental pattern in these two regions. CYFIP1 was expressed at all ages and peaked in the third post-natal week. In contrast, CYFIP2 and 82-FIP (only in forebrain regions) were moderately expressed at P3 and gradually increased after P7. In general, the expression pattern of each protein was similar in the regions examined, except for 82-FIP, which exhibited a strong expression at P3 and low levels at later developmental stages in the cerebellum. Our data indicate that FMRP and its interacting proteins have distinct developmental patterns of expression and suggest that FMRP may be preferentially associated to certain proteins in

  18. Protein expression on Cr resistant microorganism using electrophoresis method

    Directory of Open Access Journals (Sweden)

    SAJIDAN

    2009-01-01

    Full Text Available Fatmawati U, Suranto, Sajidan. 2009. Protein expression on Cr resistant microorganism using electrophoresis method. Nusantara Bioscience 1: 31-37. Hexavalent chromium (Cr(VI is known as toxic heavy metals, so the need is reduced to Cr(III is much less toxicity. Pseudomonas aeruginosa, Pseudomonas putida, Klebsiella pneumoniae, Pantoea sp. and Saccharomyces cerevisiae are resistant Cr(VI microorganism and have ability to reduce Cr(VI. The aim of this research is to know ability of microorganism to reduce Cr(VI and to know protein band pattern between Cr(VI resistant microorganism and non resistant microorganism which inoculated on LB broth. SDS-PAGE was used to indentify protein expression. While, Cr(VI concentration was identified by 1.5 diphenylcarbazide method. The quantitative data was analyzed by two factorial ANOVA that continued with DMRT at 1% level test. The qualitative data i.e. protein expression analyzed by relative mobility (Rf. The results showed that the ability of microorganisms to reduce Cr(VI at initial concentration of 0.5 ppm, 1 ppm, 5 ppm and 10 ppm may vary, the average percentage of the ability of each microorganism in reducing Cr(VI is P. putida (65% > S. cerevisiae (64.45% >. P. aeruginosa (60.73% > Pantoea sp. (50.22% > K. pneumoniae (47.82% > without microorganisms (34.25%. The adding microorganisms have significantly influenced toward reduction of Cr(VI. The SDS-PAGE shows that protein expression between resistant and not resistant microorganisms are no different, but resistant microorganisms have more protein (protein band is thicker.

  19. Using Green and Red Fluorescent Proteins to Teach Protein Expression, Purification, and Crystallization

    Science.gov (United States)

    Wu, Yifeng; Zhou, Yangbin; Song, Jiaping; Hu, Xiaojian; Ding, Yu; Zhang, Zhihong

    2008-01-01

    We have designed a laboratory curriculum using the green and red fluorescent proteins (GFP and RFP) to visualize the cloning, expression, chromatography purification, crystallization, and protease-cleavage experiments of protein science. The EGFP and DsRed monomer (mDsRed)-coding sequences were amplified by PCR and cloned into pMAL (MBP-EGFP) or…

  20. Salicylic acid enhances Staphylococcus aureus extracellular adhesin protein expression.

    Science.gov (United States)

    Alvarez, Lucía P; Barbagelata, María S; Cheung, Ambrose L; Sordelli, Daniel O; Buzzola, Fernanda R

    2011-11-01

    One of the virulence factors required by Staphylococcus aureus at the early stages of infection is Eap, a secreted adhesin that binds many host proteins and is upregulated by the two-component regulatory system saeRS. The S. aureus Newman strain harbors a mutation in saeS that is thought to be responsible for the high level of Eap expression in this strain. This study was designed to ascertain whether salicylic acid (SAL) affects the expression of Eap and the internalization of S. aureus into epithelial cells. The strain Newman treated with SAL exhibited increased levels of eap transcription and protein expression. Furthermore, SAL treatment increased the eap promoter activity. SAL treatment enhanced Eap expression in the Newman and in other S. aureus strains that do not carry the mutation in saeS. Internalization of S. aureus eap and sae mutants into the MAC-T epithelial cells was significantly decreased compared with the wild-type counterparts. In conclusion, we demonstrated that a low concentration of SAL increased S. aureus Eap expression possibly due to enhancement of sae. SAL may create the conditions for S. aureus persistence in the host, not only by decreasing the capsular polysaccharide expression as shown before, but also by enhancing Eap expression.

  1. Breast Cancer Resistance Protein Expression and 5-Fluorouracil Resistance

    Institute of Scientific and Technical Information of China (English)

    JIAN-HUI YUAN; ZHI-XIONG ZHUANG; JIN-QUAN CHENG; LONG-YUAN JIANG; WEI-DONG JI; LIANG-FENG GUO; JIAN-JUN LIU; XING-YUN XU; JING-SONG HE; XIAN-MING WANG

    2008-01-01

    To filtrate breast cancer resistance protein (BCRP)-mediated resistant agents and to investigate clinical relationship between BCRP expression and drug resistance. Methods MTT assay was performed to filtrate BCRP-mediated resistant agents with BCRP expression cell model and to detect chemosensitivity of breast cancer tissue specimens to these agents. A high performance liquid chromatography (HPLC) assay was established, and was used to measure the relative dose of intracellular retention resistant agents. RT-PCR and immununohistochemistry (IHC) were employed to investigate the BCRP expression in breast cancer tissue specimens. Results MTT assay showed that the expression of BCRP increased with the increasing resistance of 5-fluorouracil (5-Fu) (P=0.8124, P<0.01). Condusion Resistance to 5-Fu can be mediated by BCRP. Clinical chemotherapy for breast cancer patients can be optimized based on BCRP-positive expression.

  2. Regenerating human muscle fibres express GLUT3 protein

    DEFF Research Database (Denmark)

    Gaster, M; Beck-Nielsen, H; Schrøder, H D

    2002-01-01

    The presence of the GLUT3 glucose transporter protein in human muscle cells is a matter of debate. The present study was designed to establish whether GLUT3 is expressed in mature human skeletal muscle fibres and, if so, whether its expression changes under different conditions, such as metabolic...... stress (obesity, obese non-insulin-dependent diabetes mellitus), hypertrophy (training), de- and reinnervation (amyotrophic lateral sclerosis) or regeneration (polymyositis). We used an immunohistochemical approach to detect and localise GLUT3. GLUT3 immunoreactivity was not detectable in adult skeletal...... muscle fibres, nor did metabolic stress, training or de- and re-innervation induce GLUT3 expression, while a few GLUT3 expressing fibres were seen in some cases of polymyositis. In contrast, GLUT4 was expressed in all investigated muscle fibres. GLUT3 immunoreactivity was found in perineural...

  3. Secreted Proteins Defy the Expression Level-Evolutionary Rate Anticorrelation.

    Science.gov (United States)

    Feyertag, Felix; Berninsone, Patricia M; Alvarez-Ponce, David

    2017-03-01

    The rates of evolution of the proteins of any organism vary across orders of magnitude. A primary factor influencing rates of protein evolution is expression. A strong negative correlation between expression levels and evolutionary rates (the so-called E-R anticorrelation) has been observed in virtually all studied organisms. This effect is currently attributed to the abundance-dependent fitness costs of misfolding and unspecific protein-protein interactions, among other factors. Secreted proteins are folded in the endoplasmic reticulum, a compartment where chaperones, folding catalysts, and stringent quality control mechanisms promote their correct folding and may reduce the fitness costs of misfolding. In addition, confinement of secreted proteins to the extracellular space may reduce misinteractions and their deleterious effects. We hypothesize that each of these factors (the secretory pathway quality control and extracellular location) may reduce the strength of the E-R anticorrelation. Indeed, here we show that among human proteins that are secreted to the extracellular space, rates of evolution do not correlate with protein abundances. This trend is robust to controlling for several potentially confounding factors and is also observed when analyzing protein abundance data for 6 human tissues. In addition, analysis of mRNA abundance data for 32 human tissues shows that the E-R correlation is always less negative, and sometimes nonsignificant, in secreted proteins. Similar observations were made in Caenorhabditis elegans and in Escherichia coli, and to a lesser extent in Drosophila melanogaster, Saccharomyces cerevisiae and Arabidopsis thaliana. Our observations contribute to understand the causes of the E-R anticorrelation. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Bcl-2 protein expression is associated with p27 and p53 protein expressions and MIB-1 counts in breast cancer

    Directory of Open Access Journals (Sweden)

    Nishizaki Takashi

    2006-07-01

    Full Text Available Abstract Background Recent experimental studies have shown that Bcl-2, which has been established as a key player in the control of apoptosis, plays a role in regulating the cell cycle and proliferation. The aim of this study was to investigate the relationship between Bcl-2 and p27 protein expression, p53 protein expression and the proliferation activity as defined by the MIB-1 counts. The prognostic implication of Bcl-2 protein expression in relation to p27 and p53 protein expressions and MIB-1 counts for breast cancer was also evaluated. Methods The immunohistochemical expression of Bcl-2 protein was evaluated in a series of 249 invasive ductal carcinomas of the breast, in which p27 and p53 protein expressions and MIB-1 counts had been determined previously. Results The Bcl-2 protein expression was found to be decreased in 105 (42% cases. A decreased Bcl-2 protein expression was significantly correlated with a nuclear grade of III, a negative estrogen receptor, a decreased p27 protein expression, a positive p53 protein expression, positive MIB-1 counts and a positive HER2 protein expression. The incidence of a nuclear grade of III and positive MIB-1 counts increased as the number of abnormal findings of Bcl-2, p27 and p53 protein expressions increased. A univariate analysis indicated a decreased Bcl-2 protein expression to be significantly (p = 0.0089 associated with a worse disease free survival (DFS, while a multivariate analysis indicated the lymph node status and MIB-1 counts to be independently significant prognostic factors for the DFS. Conclusion The Bcl-2 protein expression has a close correlation with p27 and p53 protein expressions and the proliferation activity determined by MIB-1 counts in invasive ductal carcinoma of the breast. The prognostic value of Bcl-2 as well as p27 and p53 protein expressions was dependent on the proliferation activity in breast cancer.

  5. Expression of Prokaryotic Integral Membrane Proteins in E. coli.

    Science.gov (United States)

    Love, James D

    2017-01-01

    Production of prokaryotic membrane proteins for structural and functional studies in E. coli can be parallelized and miniaturized. All stages from cloning, expression, purification to detergent selection can be investigated using high-throughput techniques to rapidly and economically find tractable targets.

  6. Escherichia coli Protein Expression System for Acetylcholine Binding Proteins (AChBPs.

    Directory of Open Access Journals (Sweden)

    Nikita Abraham

    Full Text Available Nicotinic acetylcholine receptors (nAChR are ligand gated ion channels, identified as therapeutic targets for a range of human diseases. Drug design for nAChR related disorders is increasingly using structure-based approaches. Many of these structural insights for therapeutic lead development have been obtained from co-crystal structures of nAChR agonists and antagonists with the acetylcholine binding protein (AChBP. AChBP is a water soluble, structural and functional homolog of the extracellular, ligand-binding domain of nAChRs. Currently, AChBPs are recombinantly expressed in eukaryotic expression systems for structural and biophysical studies. Here, we report the establishment of an Escherichia coli (E. coli expression system that significantly reduces the cost and time of production compared to the existing expression systems. E. coli can efficiently express unglycosylated AChBP for crystallography and makes the expression of isotopically labelled forms feasible for NMR. We used a pHUE vector containing an N-terminal His-tagged ubiquitin fusion protein to facilitate AChBP expression in the soluble fractions, and thus avoid the need to recover protein from inclusion bodies. The purified protein yield obtained from the E. coli expression system is comparable to that obtained from existing AChBP expression systems. E. coli expressed AChBP bound nAChR agonists and antagonists with affinities matching those previously reported. Thus, the E. coli expression system significantly simplifies the expression and purification of functional AChBP for structural and biophysical studies.

  7. Heterologous expression of membrane proteins: choosing the appropriate host.

    Directory of Open Access Journals (Sweden)

    Florent Bernaudat

    Full Text Available BACKGROUND: Membrane proteins are the targets of 50% of drugs, although they only represent 1% of total cellular proteins. The first major bottleneck on the route to their functional and structural characterisation is their overexpression; and simply choosing the right system can involve many months of trial and error. This work is intended as a guide to where to start when faced with heterologous expression of a membrane protein. METHODOLOGY/PRINCIPAL FINDINGS: The expression of 20 membrane proteins, both peripheral and integral, in three prokaryotic (E. coli, L. lactis, R. sphaeroides and three eukaryotic (A. thaliana, N. benthamiana, Sf9 insect cells hosts was tested. The proteins tested were of various origins (bacteria, plants and mammals, functions (transporters, receptors, enzymes and topologies (between 0 and 13 transmembrane segments. The Gateway system was used to clone all 20 genes into appropriate vectors for the hosts to be tested. Culture conditions were optimised for each host, and specific strategies were tested, such as the use of Mistic fusions in E. coli. 17 of the 20 proteins were produced at adequate yields for functional and, in some cases, structural studies. We have formulated general recommendations to assist with choosing an appropriate system based on our observations of protein behaviour in the different hosts. CONCLUSIONS/SIGNIFICANCE: Most of the methods presented here can be quite easily implemented in other laboratories. The results highlight certain factors that should be considered when selecting an expression host. The decision aide provided should help both newcomers and old-hands to select the best system for their favourite membrane protein.

  8. Heterologous expression of membrane proteins: choosing the appropriate host.

    Science.gov (United States)

    Bernaudat, Florent; Frelet-Barrand, Annie; Pochon, Nathalie; Dementin, Sébastien; Hivin, Patrick; Boutigny, Sylvain; Rioux, Jean-Baptiste; Salvi, Daniel; Seigneurin-Berny, Daphné; Richaud, Pierre; Joyard, Jacques; Pignol, David; Sabaty, Monique; Desnos, Thierry; Pebay-Peyroula, Eva; Darrouzet, Elisabeth; Vernet, Thierry; Rolland, Norbert

    2011-01-01

    Membrane proteins are the targets of 50% of drugs, although they only represent 1% of total cellular proteins. The first major bottleneck on the route to their functional and structural characterisation is their overexpression; and simply choosing the right system can involve many months of trial and error. This work is intended as a guide to where to start when faced with heterologous expression of a membrane protein. The expression of 20 membrane proteins, both peripheral and integral, in three prokaryotic (E. coli, L. lactis, R. sphaeroides) and three eukaryotic (A. thaliana, N. benthamiana, Sf9 insect cells) hosts was tested. The proteins tested were of various origins (bacteria, plants and mammals), functions (transporters, receptors, enzymes) and topologies (between 0 and 13 transmembrane segments). The Gateway system was used to clone all 20 genes into appropriate vectors for the hosts to be tested. Culture conditions were optimised for each host, and specific strategies were tested, such as the use of Mistic fusions in E. coli. 17 of the 20 proteins were produced at adequate yields for functional and, in some cases, structural studies. We have formulated general recommendations to assist with choosing an appropriate system based on our observations of protein behaviour in the different hosts. Most of the methods presented here can be quite easily implemented in other laboratories. The results highlight certain factors that should be considered when selecting an expression host. The decision aide provided should help both newcomers and old-hands to select the best system for their favourite membrane protein. © 2011 Bernaudat et al.

  9. THE CLINICAL EXPRESSION OF HEREDITARY PROTEIN-C AND PROTEIN-S DEFICIENCY - A RELATION TO CLINICAL THROMBOTIC RISK-FACTORS AND TO LEVELS OF PROTEIN-C AND PROTEIN-S

    NARCIS (Netherlands)

    HENKENS, CMA; VANDERMEER, J; HILLEGE, JL; BOM, VJJ; HALIE, MR; van der Schaaf, W

    1993-01-01

    We investigated 103 first-degree relatives of 13 unrelated protein C or protein S deficient patients to assess the role of additional thrombotic risk factors and of protein C and protein S levels in the clinical expression of hereditary protein C and protein S deficiency. Fifty-seven relatives were

  10. Optimization of translation profiles enhances protein expression and solubility.

    Science.gov (United States)

    Hess, Anne-Katrin; Saffert, Paul; Liebeton, Klaus; Ignatova, Zoya

    2015-01-01

    mRNA is translated with a non-uniform speed that actively coordinates co-translational folding of protein domains. Using structure-based homology we identified the structural domains in epoxide hydrolases (EHs) and introduced slow-translating codons to delineate the translation of single domains. These changes in translation speed dramatically improved the solubility of two EHs of metagenomic origin in Escherichia coli. Conversely, the importance of transient attenuation for the folding, and consequently solubility, of EH was evidenced with a member of the EH family from Agrobacterium radiobacter, which partitions in the soluble fraction when expressed in E. coli. Synonymous substitutions of codons shaping the slow-transiting regions to fast-translating codons render this protein insoluble. Furthermore, we show that low protein yield can be enhanced by decreasing the free folding energy of the initial 5'-coding region, which can disrupt mRNA secondary structure and enhance ribosomal loading. This study provides direct experimental evidence that mRNA is not a mere messenger for translation of codons into amino acids but bears an additional layer of information for folding, solubility and expression level of the encoded protein. Furthermore, it provides a general frame on how to modulate and fine-tune gene expression of a target protein.

  11. Optimization of translation profiles enhances protein expression and solubility.

    Directory of Open Access Journals (Sweden)

    Anne-Katrin Hess

    Full Text Available mRNA is translated with a non-uniform speed that actively coordinates co-translational folding of protein domains. Using structure-based homology we identified the structural domains in epoxide hydrolases (EHs and introduced slow-translating codons to delineate the translation of single domains. These changes in translation speed dramatically improved the solubility of two EHs of metagenomic origin in Escherichia coli. Conversely, the importance of transient attenuation for the folding, and consequently solubility, of EH was evidenced with a member of the EH family from Agrobacterium radiobacter, which partitions in the soluble fraction when expressed in E. coli. Synonymous substitutions of codons shaping the slow-transiting regions to fast-translating codons render this protein insoluble. Furthermore, we show that low protein yield can be enhanced by decreasing the free folding energy of the initial 5'-coding region, which can disrupt mRNA secondary structure and enhance ribosomal loading. This study provides direct experimental evidence that mRNA is not a mere messenger for translation of codons into amino acids but bears an additional layer of information for folding, solubility and expression level of the encoded protein. Furthermore, it provides a general frame on how to modulate and fine-tune gene expression of a target protein.

  12. Raman microscopy of bladder cancer cells expressing green fluorescent protein

    Science.gov (United States)

    Mandair, Gurjit S.; Han, Amy L.; Keller, Evan T.; Morris, Michael D.

    2016-11-01

    Gene engineering is a commonly used tool in cellular biology to determine changes in function or expression of downstream targets. However, the impact of genetic modulation on biochemical effects is less frequently evaluated. The aim of this study is to use Raman microscopy to assess the biochemical effects of gene silencing on T24 and UMUC-13 bladder cancer cell lines. Cellular biochemical information related to nucleic acid and lipogenic components was obtained from deconvolved Raman spectra. We show that the green fluorescence protein (GFP), the chromophore that served as a fluorescent reporter for gene silencing, could also be detected by Raman microscopy. Only the gene-silenced UMUC-13 cell lines exhibited low-to-moderate GFP fluorescence as determined by fluorescence imaging and Raman spectroscopic studies. Moreover, we show that gene silencing and cell phenotype had a greater effect on nucleic acid and lipogenic components with minimal interference from GFP expression. Gene silencing was also found to perturb cellular protein secondary structure in which the amount of disorderd protein increased at the expense of more ordered protein. Overall, our study identified the spectral signature for cellular GFP expression and elucidated the effects of gene silencing on cancer cell biochemistry and protein secondary structure.

  13. The E4 protein; structure, function and patterns of expression

    Energy Technology Data Exchange (ETDEWEB)

    Doorbar, John, E-mail: jdoorba@nimr.mrc.ac.uk

    2013-10-15

    The papillomavirus E4 open reading frame (ORF) is contained within the E2 ORF, with the primary E4 gene-product (E1{sup ∧}E4) being translated from a spliced mRNA that includes the E1 initiation codon and adjacent sequences. E4 is located centrally within the E2 gene, in a region that encodes the E2 protein′s flexible hinge domain. Although a number of minor E4 transcripts have been reported, it is the product of the abundant E1{sup ∧}E4 mRNA that has been most extensively analysed. During the papillomavirus life cycle, the E1{sup ∧}E4 gene products generally become detectable at the onset of vegetative viral genome amplification as the late stages of infection begin. E4 contributes to genome amplification success and virus synthesis, with its high level of expression suggesting additional roles in virus release and/or transmission. In general, E4 is easily visualised in biopsy material by immunostaining, and can be detected in lesions caused by diverse papillomavirus types, including those of dogs, rabbits and cattle as well as humans. The E4 protein can serve as a biomarker of active virus infection, and in the case of high-risk human types also disease severity. In some cutaneous lesions, E4 can be expressed at higher levels than the virion coat proteins, and can account for as much as 30% of total lesional protein content. The E4 proteins of the Beta, Gamma and Mu HPV types assemble into distinctive cytoplasmic, and sometimes nuclear, inclusion granules. In general, the E4 proteins are expressed before L2 and L1, with their structure and function being modified, first by kinases as the infected cell progresses through the S and G2 cell cycle phases, but also by proteases as the cell exits the cell cycle and undergoes true terminal differentiation. The kinases that regulate E4 also affect other viral proteins simultaneously, and include protein kinase A, Cyclin-dependent kinase, members of the MAP Kinase family and protein kinase C. For HPV16 E1{sup

  14. 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 ...

  15. Inhibition of hepatitis C virus protein expression by RNA interference.

    Science.gov (United States)

    Sen, Adrish; Steele, Robert; Ghosh, Asish K; Basu, Arnab; Ray, Ranjit; Ray, Ratna B

    2003-10-01

    Hepatitis C virus (HCV) is a serious human pathogen and an estimated 170 million people are infected worldwide. Current therapeutic regimens have shown limited efficacy against selected genotypes of the virus. The phenomenon of RNA interference can be used to selectively block homologous genes post-transcriptionally, and has revolutionized approaches to study gene function. In this report, we have demonstrated that small interfering RNAs (siRNAs) targeted against NS5A of HCV genotype 1a specifically inhibit NS5A RNA and protein expression in a human hepatoma (HepG2) cell line. Expression of endogenous alpha-actin and the ds-RNA activated serine/threonine kinase-PKR were unaltered, demonstrating that the inhibitory effect observed from siRNA was specific to the HCV NS5A protein. We next examined whether siRNA directed against NS5A could inhibit core protein expression, the first gene product synthesized in virus infected cells due to its localization at the 5' end of the HCV polyprotein. For this purpose, a full-length cDNA clone from HCV (H77, genotype 1a) was used, and results indicated that the introduction of NS5A targeted siRNA resulted in an inhibition of NS5A and core protein expression. Moreover, we observed that this siRNA effectively inhibited NS5A mediated activation of the IL-8 promoter. Taken together, our results demonstrated that siRNA was effective in inhibiting HCV protein expression, and may have therapeutic potential to limit HCV replication in chronically infected patients.

  16. Expression, Delivery and Function of Insecticidal Proteins Expressed by Recombinant Baculoviruses

    Directory of Open Access Journals (Sweden)

    Jeremy A. Kroemer

    2015-01-01

    Full Text Available Since the development of methods for inserting and expressing genes in baculoviruses, a line of research has focused on developing recombinant baculoviruses that express insecticidal peptides and proteins. These recombinant viruses have been engineered with the goal of improving their pesticidal potential by shortening the time required for infection to kill or incapacitate insect pests and reducing the quantity of crop damage as a consequence. A wide variety of neurotoxic peptides, proteins that regulate insect physiology, degradative enzymes, and other potentially insecticidal proteins have been evaluated for their capacity to reduce the survival time of baculovirus-infected lepidopteran host larvae. Researchers have investigated the factors involved in the efficient expression and delivery of baculovirus-encoded insecticidal peptides and proteins, with much effort dedicated to identifying ideal promoters for driving transcription and signal peptides that mediate secretion of the expressed target protein. Other factors, particularly translational efficiency of transcripts derived from recombinant insecticidal genes and post-translational folding and processing of insecticidal proteins, remain relatively unexplored. The discovery of RNA interference as a gene-specific regulation mechanism offers a new approach for improvement of baculovirus biopesticidal efficacy through genetic modification.

  17. Morphine Withdrawal Modifies Prion Protein Expression in Rat Hippocampus

    Science.gov (United States)

    Mattei, Vincenzo; Martellucci, Stefano; Santilli, Francesca; Manganelli, Valeria; Garofalo, Tina; Candelise, Niccolò; Caruso, Alessandra; Sorice, Maurizio; Scaccianoce, Sergio

    2017-01-01

    The hippocampus is a vulnerable brain structure susceptible to damage during aging and chronic stress. Repeated exposure to opioids may alter the brain so that it functions normally when the drugs are present, thus, a prolonged withdrawal might lead to homeostatic changes headed for the restoration of the physiological state. Abuse of morphine may lead to Reacting Oxygen Species-induced neurodegeneration and apoptosis. It has been proposed that during morphine withdrawal, stress responses might be responsible, at least in part, for long-term changes of hippocampal plasticity. Since prion protein is involved in both, Reacting Oxygen Species mediated stress responses and synaptic plasticity, in this work we investigate the effect of opiate withdrawal in rats after morphine treatment. We hypothesize that stressful stimuli induced by opiate withdrawal, and the subsequent long-term homeostatic changes in hippocampal plasticity, might modulate the Prion protein expression. Our results indicate that abstinence from the opiate induced a time-dependent and region-specific modification in Prion protein content, indeed during morphine withdrawal a selective unbalance of hippocampal Prion Protein is observable. Moreover, Prion protein overexpression in hippocampal tissue seems to generate a dimeric structure of Prion protein and α-cleavage at the hydrophobic domain. Stress factors or toxic insults can induce cytosolic dimerization of Prion Protein through the hydrophobic domain, which in turn, it stimulates the α-cleavage and the production of neuroprotective Prion protein fragments. We speculate that this might be the mechanism by which stressful stimuli induced by opiate withdrawal and the subsequent long-term homeostatic changes in hippocampal plasticity, modulate the expression and the dynamics of Prion protein. PMID:28081197

  18. Expression and significance of P53 protein and MDM-2 protein in human gliomas

    Institute of Scientific and Technical Information of China (English)

    WANG An-liu; LIU Zhao-xia; LI Guang; ZHANG Li-wei

    2011-01-01

    Background P53 is one of the most studied tumor suppressors in the cancer research, and over 50% of human tumors carry P53 mutations. MDM-2 is amplified and/or overexpressed in a variety of human tumors of diverse tissue origin. The aim of this study was to examine the expression of P53 protein and MDM-2 protein in gliomas, and to investigate the relationship between the expression of the two proteins and the histopathological grades of glioma. The relationship between MDM-2 protein expression and P53 protein expression was also analyzed.Methods The expression of P53 protein and MDM-2 protein was immunohistochemically detected using monoclonal antibodies in 242 paraffin embedded tissues, including 30 normal brain tissues from patients with craniocerebral injury and 212 tissues from patients with primary glioma (grade Ⅰ-Ⅱ group: 5 cases of grade Ⅰ, 119 cases of grade Ⅱ; and grade Ⅲ-Ⅳ group: 53 cases of grade Ⅲ, and 35 cases of grade Ⅳ).Results The P53 positive rate was significantly higher in the glioma groups than in the control group (P <0.0001). The P53 positive rate was significantly higher in glioma tissues of grade Ⅲ-V than in glioma tissues of grade Ⅰ-Ⅱ group (P=0.001). The MDM-2 positive rate was significantly higher in glioma groups than in the control group (P <0.0001).There was no significant difference in the MDM-2 positive rate between the two glioma groups (P=0.936). The expression of P53 protein was not related to expression of MDM-2 protein (P=0.069)Conclusions Overexpression of P53 protein might be related to the occurrence and progression of glioma.Overexpression of MDM-2 protein may play an important role in glioma tumorigenesis, but may not be involved in glioma progression. The overexpression of MDM-2 protein was an early event in malignant transformation of glioma. MDM-2 may be a key player in glioma in its own right.

  19. The Role of Bromodomain Proteins in Regulating Gene Expression

    Directory of Open Access Journals (Sweden)

    Michael F. Duffy

    2012-05-01

    Full Text Available Histone modifications are important in regulating gene expression in eukaryotes. Of the numerous histone modifications which have been identified, acetylation is one of the best characterised and is generally associated with active genes. Histone acetylation can directly affect chromatin structure by neutralising charges on the histone tail, and can also function as a binding site for proteins which can directly or indirectly regulate transcription. Bromodomains specifically bind to acetylated lysine residues on histone tails, and bromodomain proteins play an important role in anchoring the complexes of which they are a part to acetylated chromatin. Bromodomain proteins are involved in a diverse range of functions, such as acetylating histones, remodeling chromatin, and recruiting other factors necessary for transcription. These proteins thus play a critical role in the regulation of transcription.

  20. Expression of Tyrosine Hydroxylase is Negatively Regulated Via Prion Protein.

    Science.gov (United States)

    da Luz, Marcio Henrique Mello; Glezer, Isaias; Xavier, Andre Machado; da Silva, Marcelo Alberti Paiva; Pino, Jessica Monteiro Volejnik; Zamith, Thiago Panaro; Vieira, Taynara Fernanda; Antonio, Bruno Brito; Antunes, Hanna Karen Moreira; Martins, Vilma Regina; Lee, Kil Sun

    2016-07-01

    Cellular prion protein (PrP(C)) is a glycoprotein of the plasma membrane that plays pleiotropic functions by interacting with multiple signaling complexes at the cell surface. Recently, a number of studies have reported the involvement of PrP(C) in dopamine metabolism and signaling, including its interactions with tyrosine hydroxylase (TH) and dopamine receptors. However, the outcomes reported by independent studies are still debatable. Therefore in this study, we investigated the effects of PrP(C) on the TH expression during the differentiation of N2a cells with dibutyryl-cAMP, a well-known cAMP analog that activates TH transcription. Upon differentiation, TH was induced with concomitant reduction of PrP(C) at protein level, but not at mRNA level. shRNA-mediated PrP(C) reduction increased the basal level of TH at both mRNA and protein levels without dibutyryl-cAMP treatment. This phenotype was reversed by re-expression of PrP(C). PrP(C) knockdown also potentiated the effect of dibutyryl-cAMP on TH expression. Our findings suggest that PrP(C) has suppressive effects on TH expression. As a consequence, altered PrP(C) functions may affect the regulation of dopamine metabolism and related neurological disorders.

  1. Comparative temporospatial expression profiling of murine amelotin protein during amelogenesis.

    Science.gov (United States)

    Somogyi-Ganss, Eszter; Nakayama, Yohei; Iwasaki, Kengo; Nakano, Yukiko; Stolf, Daiana; McKee, Marc D; Ganss, Bernhard

    2012-01-01

    Tooth enamel is formed in a typical biomineralization process under the guidance of specific organic components. Amelotin (AMTN) is a recently identified, secreted protein that is transcribed predominantly during the maturation stage of enamel formation, but its protein expression profile throughout amelogenesis has not been described in detail. The main objective of this study was to define the spatiotemporal expression profile of AMTN during tooth development in comparison with other known enamel proteins. A peptide antibody against AMTN was raised in rabbits, affinity purified and used for immunohistochemical analyses on sagittal and transverse paraffin sections of decalcified mouse hemimandibles. The localization of AMTN was compared to that of known enamel proteins amelogenin, ameloblastin, enamelin, odontogenic ameloblast-associated/amyloid in Pindborg tumors and kallikrein 4. Three-dimensional images of AMTN localization in molars at selected ages were reconstructed from serial stained sections, and transmission electron microscopy was used for ultrastructural localization of AMTN. AMTN was detected in ameloblasts of molars in a transient fashion, declining at the time of tooth eruption. Prominent expression in maturation stage ameloblasts of the continuously erupting incisor persisted into adulthood. In contrast, amelogenin, ameloblastin and enamelin were predominantly found during the early secretory stage, while odontogenic ameloblast-associated/amyloid in Pindborg tumors and kallikrein 4 expression in maturation stage ameloblasts paralleled that of AMTN. Secreted AMTN was detected at the interface between ameloblasts and the mineralized enamel. Recombinant AMTN protein did not mediate cell attachment in vitro. These results suggest a primary role for AMTN in the late stages of enamel mineralization.

  2. Bacteria and protozoa differentially modulate the expression of Rab proteins.

    Directory of Open Access Journals (Sweden)

    Elsa Seixas

    Full Text Available Phagocytic cells represent an important line of innate defense against microorganisms. Uptake of microorganisms by these cells involves the formation of a phagosome that matures by fusing with endocytic compartments, resulting in killing of the enclosed microbe. Small GTPases of the Rab family are key regulators of vesicular trafficking in the endocytic pathway. Intracellular pathogens can interfere with the function of these proteins in order to subvert host immune responses. However, it is unknown if this subversion can be achieved through the modulation of Rab gene expression. We compared the expression level of 23 distinct Rab GTPases in mouse macrophages after infection with the protozoan Plasmodium berghei, and the bacteria Escherichia coli and Salmonella enterica. We found that P. berghei induces an increase in the expression of a different set of Rab genes than E. coli and S. enterica, which behaved similarly. Strikingly, when one of the Rab proteins whose expression was increased by P. berghei, namely Rab14, was silenced, we observed a significant increase in the phagocytosis of P. berghei, whereas Rab14 overexpression led to a decrease in phagocytosis. This suggests that the parasite might induce the increase of Rab14 expression for its own advantage. Similarly, when Rab9a, whose expression was increased by E. coli and S. enterica, was silenced, we observed an increase in the phagocytosis of both bacterial species, whereas Rab9a overexpression caused a reduction in phagocytosis. This further suggests that the modulation of Rab gene expression could represent a mechanism of immune evasion. Thus, our study analyzes the modulation of Rab gene expression induced by bacteria and protozoa and suggests that this modulation could be necessary for the success of microbial infection.

  3. Transgenic expression of green fluorescent protein in mouse oxytocin neurones.

    Science.gov (United States)

    Young, W S; Iacangelo, A; Luo, X Z; King, C; Duncan, K; Ginns, E I

    1999-12-01

    Routine targeting of neurones for expression of exogenous genes would facilitate our ability to manipulate their internal milieu or functions, providing insight into physiology of neurones. The magnocellular neurones of the paraventricular and supraoptic nuclei of the hypothalamus have been the objects of limited success by this approach. Here we report on the placement of the enhanced green fluorescent protein (eGFP) coding sequence at various locations within an oxytocin transgene. Placement within the first exon yielded little to no expression, whereas placement in the third exon (as an in-frame fusion with the carboxyl terminus of the oxytocin preprohormone) resulted in cell-specific expression of eGFP in oxytocin neurones. Furthermore, placement of the eGFP sequence downstream of a picornavirus internal ribosomal entry site (IRES), also in the third exon, allowed expression of the eGFP as a separate protein. Other coding sequences should now be amenable to expression within oxytocin neurones to study their physiology.

  4. Stepwise optimization of a low-temperature Bacillus subtilis expression system for "difficult to express" proteins.

    Science.gov (United States)

    Welsch, Norma; Homuth, Georg; Schweder, Thomas

    2015-08-01

    In order to improve the overproduction of "difficult to express" proteins, a low-temperature expression system for Bacillus subtilis based on the cold-inducible promoter of the desaturase-encoding des gene was constructed. Selected regulatory DNA sequence elements from B. subtilis genes known to be cold-inducible were fused to different model genes. It could be demonstrated that these regulatory elements are able to mediate increased heterologous gene expression, either by improved translation efficiency or by higher messenger RNA (mRNA) stability. In case of a cold-adapted β-galactosidase from Pseudoalteromonas haloplanktis TAE79A serving as the model, significantly higher expression was achieved by fusing its coding sequence to the so-called "downstream box" sequence of cspB encoding the major B. subtilis cold-shock protein. The combination of this fusion with a cspB 5'-UTR stem-loop structure resulted in further enhancement of the β-galactosidase expression. In addition, integration of the transcription terminator of the B. subtilis cold-inducible bkd operon downstream of the target genes caused a higher mRNA stability and enabled thus a further significant increase in expression. Finally, the fully optimized expression system was validated by overproducing a B. subtilis xylanase as well as an α-glucosidase from Saccharomyces cerevisiae, the latter known for tending to form inclusion bodies. These analyses verified the applicability of the engineered expression system for extracellular and intracellular protein synthesis in B. subtilis, thereby confirming the suitability of this host organism for the overproduction of critical, poorly soluble proteins.

  5. Heat-shock protein expression in canine corneal wound healing.

    Science.gov (United States)

    Peterson, Cornelia W M; Carter, Renee T; Bentley, Ellison; Murphy, Christopher J; Chandler, Heather L

    2016-05-01

    Heat-shock proteins, particularly the 70-kDa member (Hsp70), have been implicated in facilitating wound healing in multiple tissues. Expression and localization of three HSPs were assessed in normal and wounded canine corneas to elucidate a role in epithelial healing. Paraffin-embedded normal corneas, acute and repeatedly abraded corneas, and keratectomies of spontaneous chronic corneal epithelial defects (SCCEDs) were subjected to routine immunohistochemistry for Hsp27, 47, and 70 expression. Ex vivo corneal defects were created and treated with anti-HSPs or IgG controls, and wound healing was monitored. Primary cultures of canine corneal stromal fibroblasts and corneal epithelial cells were treated with exogenous Hsp70, and an artificial wound was created in vitro to monitor restoration of the monolayer. Normal canine corneas exhibited constitutive expression of all HSPs evaluated. Inducible expression was demonstrated in acutely wounded tissues, and expression in the chronically abraded corneas was relocalized. All HSP expression was below the limits of detection in the epithelium of SCCED samples. Inhibition of HSPs in culture resulted in delayed wound healing when compared to controls. Hsp70-treated fibroblasts demonstrated significantly (P healing response, and suppressed expression may contribute to the pathophysiology of nonhealing defects. © 2015 American College of Veterinary Ophthalmologists.

  6. BMP-7 PROTEIN EXPRESSION IS DOWNREGULATED IN HUMAN DIABETIC NEPHROPATHY.

    Science.gov (United States)

    Ivanac-Janković, Renata; Ćorić, Marijana; Furić-Čunko, Vesna; Lovičić, Vesna; Bašić-Jukić, Nikolina; Kes, Petar

    2015-06-01

    Bone morphogenetic protein-7 (BMP-7) is expressed in all parts of the normal kidney parenchyma, being highest in the epithelium of proximal tubules. It protects kidney against acute and chronic injury, inflammation and fibrosis. Diabetic nephropathy is the leading cause of chronic kidney disease, and is characterized by decreased expression of BMP-7. The aim of our study was to analyze whether the expression of BMP-7 is significantly changed in advanced stages of human diabetic nephropathy. Immunohistochemical analysis of the expression of BMP-7 was performed on archival material of 30 patients that underwent renal biopsy and had confirmed diagnosis of diabetic nephropathy. Results showed that BMP-7 was differently expressed in the cytoplasm of epithelial cells of proximal tubules and podocytes among all stages of diabetic nephropathy. At early stages of diabetic nephropathy, BMP-7 was strongly positive in proximal tubules and podocytes, while low expression was recorded in the majority of samples at advanced stages. In conclusion, increased expression of BMP-7 at initial stages of diabetic nephropathy with subsequent decrease at advanced stage highlights the role of BMP-7 in the protection of kidney structure and function. Further investigations should be focused on disturbances of BMP-7 receptors and signaling pathways in patients with diabetic nephropathy.

  7. A new essential protein discovery method based on the integration of protein-protein interaction and gene expression data

    Directory of Open Access Journals (Sweden)

    Li Min

    2012-03-01

    Full Text Available Abstract Background Identification of essential proteins is always a challenging task since it requires experimental approaches that are time-consuming and laborious. With the advances in high throughput technologies, a large number of protein-protein interactions are available, which have produced unprecedented opportunities for detecting proteins' essentialities from the network level. There have been a series of computational approaches proposed for predicting essential proteins based on network topologies. However, the network topology-based centrality measures are very sensitive to the robustness of network. Therefore, a new robust essential protein discovery method would be of great value. Results In this paper, we propose a new centrality measure, named PeC, based on the integration of protein-protein interaction and gene expression data. The performance of PeC is validated based on the protein-protein interaction network of Saccharomyces cerevisiae. The experimental results show that the predicted precision of PeC clearly exceeds that of the other fifteen previously proposed centrality measures: Degree Centrality (DC, Betweenness Centrality (BC, Closeness Centrality (CC, Subgraph Centrality (SC, Eigenvector Centrality (EC, Information Centrality (IC, Bottle Neck (BN, Density of Maximum Neighborhood Component (DMNC, Local Average Connectivity-based method (LAC, Sum of ECC (SoECC, Range-Limited Centrality (RL, L-index (LI, Leader Rank (LR, Normalized α-Centrality (NC, and Moduland-Centrality (MC. Especially, the improvement of PeC over the classic centrality measures (BC, CC, SC, EC, and BN is more than 50% when predicting no more than 500 proteins. Conclusions We demonstrate that the integration of protein-protein interaction network and gene expression data can help improve the precision of predicting essential proteins. The new centrality measure, PeC, is an effective essential protein discovery method.

  8. Generation of transgenic dogs that conditionally express green fluorescent protein.

    Science.gov (United States)

    Kim, Min Jung; Oh, Hyun Ju; Park, Jung Eun; Kim, Geon A; Hong, So Gun; Jang, Goo; Kwon, Mo Sun; Koo, Bon Chul; Kim, Teoan; Kang, Sung Keun; Ra, Jeong Chan; Ko, Chemyong; Lee, Byeong Chun

    2011-06-01

    We report the creation of a transgenic dog that conditionally expresses eGFP (enhanced green fluorescent protein) under the regulation of doxycycline. Briefly, fetal fibroblasts infected with a Tet-on eGFP vector were used for somatic cell nuclear transfer. Subsequently reconstructed oocytes were transferred to recipients. Three clones having transgenes were born and one dog was alive. The dog showed all features of inducible expression of eGFP upon doxycycline administration, and successful breeding resulted in eGFP-positive puppies, confirming stable insertion of the transgene into the genome. This inducible dog model will be useful for a variety of medical research studies.

  9. Transcriptional Modulation of Heat-Shock Protein Gene Expression

    Directory of Open Access Journals (Sweden)

    Anastasis Stephanou

    2011-01-01

    Full Text Available Heat-shock proteins (Hsps are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex signaling pathways regulating Hsp expression may lead to novel therapeutic targets.

  10. Transcriptional modulation of heat-shock protein gene expression.

    Science.gov (United States)

    Stephanou, Anastasis; Latchman, David S

    2011-01-01

    Heat-shock proteins (Hsps) are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex signaling pathways regulating Hsp expression may lead to novel therapeutic targets.

  11. Targeting angiogenesis via a c-Myc/hypoxia-inducible factor-1alpha-dependent pathway in multiple myeloma.

    Science.gov (United States)

    Zhang, Jing; Sattler, Martin; Tonon, Giovanni; Grabher, Clemens; Lababidi, Samir; Zimmerhackl, Alexander; Raab, Marc S; Vallet, Sonia; Zhou, Yiming; Cartron, Marie-Astrid; Hideshima, Teru; Tai, Yu-Tzu; Chauhan, Dharminder; Anderson, Kenneth C; Podar, Klaus

    2009-06-15

    Bone marrow angiogenesis is associated with multiple myeloma (MM) progression. Here, we report high constitutive hypoxia-inducible factor-1alpha (Hif-1alpha) expression in MM cells, which is associated with oncogenic c-Myc. A drug screen for anti-MM agents that decrease Hif-1alpha and c-Myc levels identified a variety of compounds, including bortezomib, lenalidomide, enzastaurin, and adaphostin. Functionally, based on transient knockdowns and overexpression, our data delineate a c-Myc/Hif-1alpha-dependent pathway mediating vascular endothelial growth factor production and secretion. The antiangiogenic activity of our tool compound, adaphostin, was subsequently shown in a zebrafish model and translated into a preclinical in vitro and in vivo model of MM in the bone marrow milieu. Our data, therefore, identify Hif-1alpha as a novel molecular target in MM and add another facet to anti-MM drug activity.

  12. Recombinant Dragline Silk-Like Proteins-Expression and Purification.

    Science.gov (United States)

    Gaines, William A; Marcotte, William R

    2011-03-01

    Spider dragline silk is a proteinaceous fiber with impressive physical characteristics making it attractive for use in advanced materials. The fiber is composed of two proteins (spidroins MaSp1 and MaSp2), each of which contains a large central repeat array flanked by non-repetitive N- and C-terminal domains. The repeat arrays appear to be largely responsible for the tensile properties of the fiber, suggesting that the N- and C-terminal domains may be involved in self-assembly. We recently isolated the MaSp1 and MaSp2 N-terminal domains from Nephila clavipes and have incorporated these into mini-silk genes for expression in transgenic systems. Current efforts involve the development of expression vectors that will allow purification using a removable affinity tag for scalable protein purification.

  13. Disposable bioreactors for inoculum production and protein expression.

    Science.gov (United States)

    Eibl, Regine; Löffelholz, Christian; Eibl, Dieter

    2014-01-01

    Disposable bioreactors have been increasingly implemented over the past ten years. This relates to both R & D and commercial manufacture, in particular, in animal cell-based processes. Among the numerous disposable bioreactors which are available today, wave-mixed bag bioreactors and stirred bioreactors are predominant. Whereas wave-mixed bag bioreactors represent the system of choice for inoculum production, stirred systems are often preferred for protein expression. For this reason, the authors present protocols instructing the reader how to use the wave-mixed BIOSTAT CultiBag RM 20 L for inoculum production and the stirred UniVessel SU 2 L for recombinant protein production at benchtop scale. All methods described are based on a Chinese hamster ovary (CHO) suspension cell line expressing the human placental secreted alkaline phosphatase (SEAP).

  14. Splice Isoforms of Phosducin-like Protein Control the Expression of Heterotrimeric G Proteins*

    Science.gov (United States)

    Gao, Xueli; Sinha, Satyabrata; Belcastro, Marycharmain; Woodard, Catherine; Ramamurthy, Visvanathan; Stoilov, Peter; Sokolov, Maxim

    2013-01-01

    Heterotrimeric G proteins play an essential role in cellular signaling; however, the mechanism regulating their synthesis and assembly remains poorly understood. A line of evidence indicates that the posttranslational processing of G protein β subunits begins inside the protein-folding chamber of the chaperonin containing t-complex protein 1. This process is facilitated by the ubiquitously expressed phosducin-like protein (PhLP), which is thought to act as a CCT co-factor. Here we demonstrate that alternative splicing of the PhLP gene gives rise to a transcript encoding a truncated, short protein (PhLPs) that is broadly expressed in human tissues but absent in mice. Seeking to elucidate the function of PhLPs, we expressed this protein in the rod photoreceptors of mice and found that this manipulation caused a dramatic translational and posttranslational suppression of rod heterotrimeric G proteins. The investigation of the underlying mechanism revealed that PhLPs disrupts the folding of Gβ and the assembly of Gβ and Gγ subunits, events normally assisted by PhLP, by forming a stable and apparently inactive tertiary complex with CCT preloaded with nascent Gβ. As a result, the cellular levels of Gβ and Gγ, which depends on Gβ for stability, decline. In addition, PhLPs evokes a profound and rather specific down-regulation of the Gα transcript, leading to a complete disappearance of the protein. This study provides the first evidence of a generic mechanism, whereby the splicing of the PhLP gene could potentially and efficiently regulate the cellular levels of heterotrimeric G proteins. PMID:23888055

  15. Transcriptional Modulation of Heat-Shock Protein Gene Expression

    OpenAIRE

    Anastasis Stephanou; Latchman, David S.

    2011-01-01

    Heat-shock proteins (Hsps) are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex sig...

  16. Transcriptional modulation of heat-shock protein gene expression.

    OpenAIRE

    A. Stephanou; Latchman, D S

    2011-01-01

    Heat-shock proteins (Hsps) are molecular chaperones that are ubiquitously expressed but are also induced in cells exposed to stressful stimuli. Hsps have been implicated in the induction and propagation of several diseases. This paper focuses on regulatory factors that control the transcription of the genes encoding Hsps. We also highlight how distinct transcription factors are able to interact and modulate Hsps in different pathological states. Thus, a better understanding of the complex sig...

  17. Expression of 16 Nitrogenase Proteins within the Plant Mitochondrial Matrix

    Science.gov (United States)

    Allen, Robert S.; Tilbrook, Kimberley; Warden, Andrew C.; Campbell, Peter C.; Rolland, Vivien; Singh, Surinder P.; Wood, Craig C.

    2017-01-01

    The industrial production and use of nitrogenous fertilizer involves significant environmental and economic costs. Strategies to reduce fertilizer dependency are required to address the world's increasing demand for sustainable food, fibers, and biofuels. Biological nitrogen fixation, a process unique to diazatrophic bacteria, is catalyzed by the nitrogenase complex, and reconstituting this function in plant cells is an ambitious biotechnological strategy to reduce fertilizer use. Here we establish that the full array of biosynthetic and catalytic nitrogenase (Nif) proteins from the diazotroph Klebsiella pneumoniae can be individually expressed as mitochondrial targeting peptide (MTP)-Nif fusions in Nicotiana benthamiana. We show that these are correctly targeted to the plant mitochondrial matrix, a subcellular location with biochemical and genetic characteristics potentially supportive of nitrogenase function. Although Nif proteins B, D, E, F, H, J, K, M, N, Q, S, U, V, X, Y, and Z were all detectable by Western blot analysis, the NifD catalytic component was the least abundant. To address this problem, a translational fusion between NifD and NifK was designed based on the crystal structure of the nitrogenase MoFe protein heterodimer. This fusion protein enabled equimolar NifD:NifK stoichiometry and improved NifD expression levels in plants. Finally, four MTP-Nif fusion proteins (B, S, H, Y) were successfully co-expressed, demonstrating that multiple components of nitrogenase can be targeted to plant mitochondria. These results establish the feasibility of reconstituting the complete componentry for nitrogenase in plant cells, within an intracellular environment that could support the conversion of nitrogen gas into ammonia. PMID:28316608

  18. Expression of 16 Nitrogenase Proteins within the Plant Mitochondrial Matrix.

    Science.gov (United States)

    Allen, Robert S; Tilbrook, Kimberley; Warden, Andrew C; Campbell, Peter C; Rolland, Vivien; Singh, Surinder P; Wood, Craig C

    2017-01-01

    The industrial production and use of nitrogenous fertilizer involves significant environmental and economic costs. Strategies to reduce fertilizer dependency are required to address the world's increasing demand for sustainable food, fibers, and biofuels. Biological nitrogen fixation, a process unique to diazatrophic bacteria, is catalyzed by the nitrogenase complex, and reconstituting this function in plant cells is an ambitious biotechnological strategy to reduce fertilizer use. Here we establish that the full array of biosynthetic and catalytic nitrogenase (Nif) proteins from the diazotroph Klebsiella pneumoniae can be individually expressed as mitochondrial targeting peptide (MTP)-Nif fusions in Nicotiana benthamiana. We show that these are correctly targeted to the plant mitochondrial matrix, a subcellular location with biochemical and genetic characteristics potentially supportive of nitrogenase function. Although Nif proteins B, D, E, F, H, J, K, M, N, Q, S, U, V, X, Y, and Z were all detectable by Western blot analysis, the NifD catalytic component was the least abundant. To address this problem, a translational fusion between NifD and NifK was designed based on the crystal structure of the nitrogenase MoFe protein heterodimer. This fusion protein enabled equimolar NifD:NifK stoichiometry and improved NifD expression levels in plants. Finally, four MTP-Nif fusion proteins (B, S, H, Y) were successfully co-expressed, demonstrating that multiple components of nitrogenase can be targeted to plant mitochondria. These results establish the feasibility of reconstituting the complete componentry for nitrogenase in plant cells, within an intracellular environment that could support the conversion of nitrogen gas into ammonia.

  19. Hypoxia decreases podocyte expression of slit diaphragm proteins

    Directory of Open Access Journals (Sweden)

    Lu H

    2012-07-01

    Full Text Available Hong Lu,1 Gaurav Kapur,1 Tej K Mattoo,1 William D Lyman1,21Carman and Ann Adams Department of Pediatrics, 2Children's Research Center of Michigan, Children's Hospital of Michigan, Detroit, MI, USABackground: Chronic hypoxia contributes to progressive tubulointerstitial injury and, consequently, renal failure. However, the effect of hypoxia on glomerular podocytes, which are integral to the slit diaphragm complex and responsible for selectivity of the glomerular filtration barrier, has not been completely determined. Methods: Conditionally immortalized mouse podocyte cells were exposed to hypoxic (1% O2 or normoxic (room air conditions for 24, 48, or 72 hours, after which cell viability was determined by MTT assay. Cells were stained with podocin and phalloidin to determine podocin and intracellular actin distribution. Expression of synaptopodin, CD2-associated protein (CD2AP, NcK, transforming growth factor-β1 (TGF-β1, hypoxia-inducible factor (HIF-1α were evaluated by real-time polymerase chain reaction.Results: Podocytes exposed to hypoxia had significantly reduced viability at 48 (87% and 72 hours (66%. There was disarrangement of intracellular filament actin by phalloidin staining, a 30% weaker fluorescence intensity by podocin staining, significantly reduced expression of synaptopodin (12%, CD2AP (42%, NcK (38%, and increased expression of TGF-β1 and P-ERK after hypoxia treatment.Conclusion: Podocyte exposure to hypoxia leads to reduced viability and SD protein expression, which may explain persistent and/or increasing proteinuria in patients with progressive renal failure. Increased expression of TGF-β1 and P-ERK is associated with apoptosis and fibrosis, which could be the link between hypoxia and glomerular injury.Keywords: podocytes, hypoxia, slit-diaphragm proteins

  20. Differential expression of ribosomal proteins in myelodysplastic syndromes.

    Science.gov (United States)

    Rinker, Elizabeth B; Dueber, Julie C; Qualtieri, Julianne; Tedesco, Jason; Erdogan, Begum; Bosompem, Amma; Kim, Annette S

    2016-02-01

    Aberrations of ribosomal biogenesis have been implicated in several congenital bone marrow failure syndromes, such as Diamond-Blackfan anaemia, Shwachman-Diamond syndrome and Dyskeratosis Congenita. Recent studies have identified haploinsufficiency of RPS14 in the acquired bone marrow disease isolated 5q minus syndrome, a subtype of myelodysplastic syndromes (MDS). However, the expression of various proteins comprising the ribosomal subunits and other proteins enzymatically involved in the synthesis of the ribosome has not been explored in non-5q minus MDS. Furthermore, differences in the effects of these expression alterations among myeloid, erythroid and megakaryocyte lineages have not been well elucidated. We examined the expression of several proteins related to ribosomal biogenesis in bone marrow biopsy specimens from patients with MDS (5q minus patients excluded) and controls with no known myeloid disease. Specifically, we found that there is overexpression of RPS24, DKC1 and SBDS in MDS. This overexpression is in contrast to the haploinsufficiency identified in the congenital bone marrow failure syndromes and in acquired 5q minus MDS. Potential mechanisms for these differences and aetiology for these findings in MDS are discussed.

  1. Expression of DNA-dependent protein kinase in human granulocytes

    Institute of Scientific and Technical Information of China (English)

    Annahita SALLMYR; Anna MILLER; Aida GABDOULKHAKOVA; Valentina SAFRONOVA; Gunnel HENRIKSSON; Anders BREDBERG

    2004-01-01

    Human polymorphonuclear leukocytes (PMN) have been reported to completely lack of DNA-dependent protein kinase (DNA-PK) which is composed of Ku protein and the catalytic subunit DNA-PKcs, needed for nonhomologous end-joining (NHEJ) of DNA double-strand breaks. Promyelocytic HL-60 cells express a variant form of Ku resulting in enhanced radiation sensitivity. This raises the question if low efficiency of NHEJ, instrumental for the cellular repair of oxidative damage, is a normal characteristic of myeloid differentiation. Here we confirmed the complete lack of DNAPK in P MN protein extracts, and the expression of the truncated Ku86 variant form in HL-60. However, this degradation of DNA-PK was shown to be due to a DNA-PK-degrading protease in PMN and HL-60. In addition, by using a protease-resistant whole cell assay, both Ku86 and DNA-PKcs could be demonstrated in PMN, suggesting the previously reported absence in PMN of DNA-PK to be an artefact. The levels of Ku86 and DNA-PKcs were much reduced in PMN, as compared with that of the lymphocytes, whereas HL-60 displayed a markedly elevated DNA-PK concentration.In conclusion, our findings provide evidence of reduced, not depleted expression of DNA-PK during the mature stages of myeloid differentiation.

  2. Altered Level of Soluble fms-like Tyrosine Kinase 1 (sFlt1 and Hypoxia Inducible Factor-1alpha (HIF-1alpha in Normotensive Pregnancy and Preeclampsia

    Directory of Open Access Journals (Sweden)

    John Wantania

    2013-08-01

    Full Text Available BACKGROUND: Preeclampsia is still a significant problem worldwide. Of the many suggested mechanisms of its pathogenesis, the latest one is the balance of angiogenic factor and its relationship with hypoxia factors. The objective of this study was to observe changes or dynamic process of soluble fms-like tyrosine kinase 1 (sFlt1 as anti-angiogenic factor and hypoxia inducible factor 1-alpha (HIF-1α as hypoxia marker in normotensive pregnancy and preeclampsia in mid-term and full-term pregnancies. METHODS: A cohort study was conducted on 36 normotensive subjects, first examination was conducted at 20-28 weeks of gestation. Then second examination was conducted at the time of preeclampsia diagnosed or full-term pregnancy. Preeclampsia was characterized by hypertension of systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, with two readings separated in 4-6 hours period, and/or proteinuria with urine dipstick of ≥1+ or ≥300 mg per 24 hours. Examinations of sFlt-1 and HIF-1α were done by enzyme-linked immunosorbent assay method. Statistical analysis was done using a significance level of p<0.05. RESULTS: Concentration of sFlt-1 was elevated in normotensive pregnancy and preeclampsia. Higher sFlt-1 concentration elevation was seen in preeclamptic group comparing to normotensive group, although not significant. This finding was related to the fact that investigated subjects were mostly developing mild preeclampsia merely. Comparing to normotensive group, preeclamptic group had higher HIF-1α concentration-per-week elevation, but not significant. There was a positive correlation between concentrations of sFlt-1 and HIF-1α, but not significant. CONCLUSIONS: sFlt-1 concentration elevation was correlated with preeclampsia. Therefore comparing to averages, changes of sFlt-1 concentrations were more important. Concentrations of HIF-1α and sFlt-1 were positively correlated. KEYWORDS: sFlt-1, HIF-1α, preeclampsia, normotension.

  3. Romance of the three kingdoms: RORgammat allies with HIF1alpha against FoxP3 in regulating T cell metabolism and differentiation.

    Science.gov (United States)

    Tsun, Andy; Chen, Zuojia; Li, Bin

    2011-10-01

    Regulatory T (Treg) cells play an essential role in immune homeostasis by controlling the function of various immune effector cells, including RAR-related orphan receptor gammat(+) (RORγt(+)) T helper 17 (Th17) cells. Foekhead box P(3) (FoxP(3)) is the master regulator of Treg cell function, while RORγt is the key transcription factor for the induction of the interleukin (IL)-17 family of cytokines during Th17 cell differentiation. FoxP3 can directly interact with and negatively regulate the function of RORγt, to determine the balance between induced Treg (iTreg) and Th17 cell polarization. Two recent independent studies from the Pan and Chi Labs have shown how hypoxia-inducible factor 1 alpha (HIF1α) is able to tip the balance of T cell differentiation toward the Th17 lineage by responding to the local changes in metabolic shift or an increase in proinflammatory mediators in the microenvironment. By allying with HIF1α, RORγt wins the fight against FoxP3 and Treg cell commitment.

  4. Expression of P16 protein and Bcl-2 protein in malignant eyelid tumors

    Institute of Scientific and Technical Information of China (English)

    牛膺筠; 周占宇; 刘夫玲; 王红云

    2002-01-01

    Objective To investigate the relationship between P16 gene (the tumor suppressor gene) and the bcl-2 gene (the apoptosis inhibitor gene) and the incidence and development of malignant eyelid tumors. Methods The streptavidin-biotin-peroxidase complex immunohistochemistry method was used to study the expression of P16 gene and the bcl-2 gene in 96 cases of malignant eyelid tumors. Results Among the 96 cases, there were 40 basal cell carcinomas (BCCs), 33 squamous carcinomas and 23 sebaceous carcinoma, with P16 protein positive (nuclear staining) rates 70%, 54.6% and 56.5%, respectively. The P16 positive rate was negatively correlated with the degree of tumor histological differentiation, and the rate difference between the high differentiated carcinomas was significant (P<0.05). Positive Bcl-2 protein expression was detected in the cytoplasm. All 40 BCC cases were Bcl-2 positive, and nearly all of the tumor cells showed positive cytoplasmic expression, while in the 33 squamous cell carcinoma cases only one showed positive focal reaction, and the staining in the other 32 cases was relatively faint. None of the 23 sebaceous carcinomas expressed Bcl-2. Conclusions The expression of the P16 protein was related to the occurrence and degree of differentiation of malignant eyelid tumors. The overexpression of the Bcl-2 protein suggests that suppression of apoptosis might play a role in the tumorigenesis of BCC.

  5. Efficient expression and purification of biologically active human cystatin proteins.

    Science.gov (United States)

    Chauhan, Sakshi; Tomar, Raghuvir S

    2016-02-01

    Cystatins are reversible cysteine protease inhibitor proteins. They are known to play important roles in controlling cathepsins, neurodegenerative disease, and in immune system regulation. Production of recombinant cystatin proteins is important for biochemical and function characterization. In this study, we cloned and expressed human stefin A, stefin B and cystatin C in Escherichia coli. Human stefin A, stefin B and cystatin C were purified from soluble fraction. For cystatin C, we used various chaperone plasmids to make cystatin C soluble, as it is reported to localize in inclusion bodies. Trigger factor, GroES-GroEL, DnaK-DnaJ-GrpE chaperones lead to the presence of cystatin C in the soluble fraction. Immobilized metal affinity chromatography, glutathione sepharose and anion exchange chromatography techniques were employed for efficient purification of these proteins. Their biological activities were tested by inhibition assays against cathepsin L and H3 protease.

  6. The E4 protein; structure, function and patterns of expression.

    Science.gov (United States)

    Doorbar, John

    2013-10-01

    The papillomavirus E4 open reading frame (ORF) is contained within the E2 ORF, with the primary E4 gene-product (E1^E4) being translated from a spliced mRNA that includes the E1 initiation codon and adjacent sequences. E4 is located centrally within the E2 gene, in a region that encodes the E2 protein's flexible hinge domain. Although a number of minor E4 transcripts have been reported, it is the product of the abundant E1^E4 mRNA that has been most extensively analysed. During the papillomavirus life cycle, the E1^E4 gene products generally become detectable at the onset of vegetative viral genome amplification as the late stages of infection begin. E4 contributes to genome amplification success and virus synthesis, with its high level of expression suggesting additional roles in virus release and/or transmission. In general, E4 is easily visualised in biopsy material by immunostaining, and can be detected in lesions caused by diverse papillomavirus types, including those of dogs, rabbits and cattle as well as humans. The E4 protein can serve as a biomarker of active virus infection, and in the case of high-risk human types also disease severity. In some cutaneous lesions, E4 can be expressed at higher levels than the virion coat proteins, and can account for as much as 30% of total lesional protein content. The E4 proteins of the Beta, Gamma and Mu HPV types assemble into distinctive cytoplasmic, and sometimes nuclear, inclusion granules. In general, the E4 proteins are expressed before L2 and L1, with their structure and function being modified, first by kinases as the infected cell progresses through the S and G2 cell cycle phases, but also by proteases as the cell exits the cell cycle and undergoes true terminal differentiation. The kinases that regulate E4 also affect other viral proteins simultaneously, and include protein kinase A, Cyclin-dependent kinase, members of the MAP Kinase family and protein kinase C. For HPV16 E1^E4, these kinases regulate one of

  7. Hypoxia-mediated down-regulation of Bid and Bax in tumors occurs via hypoxia-inducible factor 1-dependent and -independent mechanisms and contributes to drug resistance

    DEFF Research Database (Denmark)

    Erler, Janine Terra; Cawthorne, Christopher J; Williams, Kaye J;

    2004-01-01

    of the Bcl-2 protein family. Oxygen deprivation of human colon cancer cells in vitro provoked decreased mRNA and protein levels of proapoptotic Bid and Bad. Hypoxia-inducible factor 1 (HIF-1) was dispensable for the down-regulation of Bad but required for that of Bid, consistent with the binding of HIF-1......alpha to a hypoxia-responsive element (positions -8484 to -8475) in the bid promoter. Oxygen deprivation resulted in proteosome-independent decreased expression of Bax in vitro, consistent with a reduction in global translation efficiency. The physiological relevance of Bid and Bax down...

  8. Identification of differentially expressed proteins in vitamin B 12

    Directory of Open Access Journals (Sweden)

    Swati Varshney

    2015-01-01

    Full Text Available Background: Vitamin B 12 (cobalamin is a water-soluble vitamin generally synthesized by microorganisms. Mammals cannot synthesize this vitamin but have evolved processes for absorption, transport and cellular uptake of this vitamin. Only about 30% of vitamin B 12 , which is bound to the protein transcobalamin (TC (Holo-TC [HoloTC] enters into the cell and hence is referred to as the biologically active form of vitamin B 12 . Vitamin B 12 deficiency leads to several complex disorders, including neurological disorders and anemia. We had earlier shown that vitamin B 12 deficiency is associated with coronary artery disease (CAD in Indian population. In the current study, using a proteomics approach we identified proteins that are differentially expressed in the plasma of individuals with low HoloTC levels. Materials and Methods: We used isobaric-tagging method of relative and absolute quantitation to identify proteins that are differently expressed in individuals with low HoloTC levels when compared to those with normal HoloTC level. Results: In two replicate isobaric tags for relative and absolute quantitation experiments several proteins involved in lipid metabolism, blood coagulation, cholesterol metabolic process, and lipoprotein metabolic process were found to be altered in individuals having low HoloTC levels. Conclusions: Our study indicates that low HoloTc levels could be a risk factor in the development of CAD.

  9. Grizzly bear corticosteroid binding globulin: Cloning and serum protein expression.

    Science.gov (United States)

    Chow, Brian A; Hamilton, Jason; Alsop, Derek; Cattet, Marc R L; Stenhouse, Gordon; Vijayan, Mathilakath M

    2010-06-01

    Serum corticosteroid levels are routinely measured as markers of stress in wild animals. However, corticosteroid levels rise rapidly in response to the acute stress of capture and restraint for sampling, limiting its use as an indicator of chronic stress. We hypothesized that serum corticosteroid binding globulin (CBG), the primary transport protein for corticosteroids in circulation, may be a better marker of the stress status prior to capture in grizzly bears (Ursus arctos). To test this, a full-length CBG cDNA was cloned and sequenced from grizzly bear testis and polyclonal antibodies were generated for detection of this protein in bear sera. The deduced nucleotide and protein sequences were 1218 bp and 405 amino acids, respectively. Multiple sequence alignments showed that grizzly bear CBG (gbCBG) was 90% and 83% identical to the dog CBG nucleotide and amino acid sequences, respectively. The affinity purified rabbit gbCBG antiserum detected grizzly bear but not human CBG. There were no sex differences in serum total cortisol concentration, while CBG expression was significantly higher in adult females compared to males. Serum cortisol levels were significantly higher in bears captured by leg-hold snare compared to those captured by remote drug delivery from helicopter. However, serum CBG expression between these two groups did not differ significantly. Overall, serum CBG levels may be a better marker of chronic stress, especially because this protein is not modulated by the stress of capture and restraint in grizzly bears.

  10. Expression of parathyroid hormone-related protein in ameloblastomas.

    Science.gov (United States)

    Ohtsuru, Mitsunobu

    2005-12-01

    Parathyroid hormone-related protein (PTHrP) was first discovered as a causative protein for hypercalcemia, which is often seen in the malignant tumor. PTHrP binds to the parathyroid hormone 1 receptor (PTH1R) for signal transduction. PTHrP-PTH1R interactions were associated with bone resorption. The present study, therefore, sought to clarify the expression of PTHrP, parathyroid hormone (PTH) and PTH1R in ameloblastoma, using RT-PCR (N = 8), immunohistochemistry (N = 23) and ELISA (N = 11) techniques. PTHrP and B-actin mRNA were detected in the all samples. Expression of PTHrP was also seen in all of the 23 cases in ameloblastoma by immunohistochemistry. There was a significant difference in PTHrP concentration by ELISA between typical unicystic type and solid type including unicystic type 3 (p = 0.0427). Only one exhibited the weak expression of PTH1R mRNA. PTH1R was observed on osteoblasts in bone around the tumor but no expression was observed on ameloblastoma cells in tumor parenchyma by immunohistochemistry. PTH was not detected in ameloblastoma by RT-PCR, immunohistochemistory as well as ELISA. In addition, hypercalcemia and increase of serum PTHrP level was observed in one case of 8 ameloblastomas. It was suggested that PTHrP level may be associated with local bone infiltration and hypercalcemia in ameloblastoma.

  11. Myocardin-related transcription factor regulates Nox4 protein expression

    DEFF Research Database (Denmark)

    Rozycki, Matthew; Bialik, Janne Folke; Speight, Pam

    2016-01-01

    TGFβ-induced expression of the NADPH oxidase Nox4 is essential for fibroblast-myofibroblast transition. Rho has been implicated in Nox4 regulation, but the underlying mechanisms are largely unknown. Myocardin-related transcription factor (MRTF), a Rho/actin polymerization-controlled coactivator...... translocation of MRTF. Because the Nox4 promoter harbors a serum response factor/MRTF cis-element (CC(A/T)6GG box), we asked if MRTF (and thus cytoskeleton organization) could regulate Nox4 expression. We show that Nox4 protein is robustly induced in kidney tubular cells exclusively by combined application...... of contact uncoupling and TGFβ. Nox4 knockdown abrogates epithelial-myofibroblast transition-associated reactive oxygen species production. Laser capture microdissection reveals increased Nox4 expression in the tubular epithelium also during obstructive nephropathy. MRTF down-regulation/inhibition suppresses...

  12. Sweeping away protein aggregation with entropic bristles: intrinsically disordered protein fusions enhance soluble expression.

    Science.gov (United States)

    Santner, Aaron A; Croy, Carrie H; Vasanwala, Farha H; Uversky, Vladimir N; Van, Ya-Yue J; Dunker, A Keith

    2012-09-18

    Intrinsically disordered, highly charged protein sequences act as entropic bristles (EBs), which, when translationally fused to partner proteins, serve as effective solubilizers by creating both a large favorable surface area for water interactions and large excluded volumes around the partner. By extending away from the partner and sweeping out large molecules, EBs can allow the target protein to fold free from interference. Using both naturally occurring and artificial polypeptides, we demonstrate the successful implementation of intrinsically disordered fusions as protein solubilizers. The artificial fusions discussed herein have a low level of sequence complexity and a high net charge but are diversified by means of distinctive amino acid compositions and lengths. Using 6xHis fusions as controls, soluble protein expression enhancements from 65% (EB60A) to 100% (EB250) were observed for a 20-protein portfolio. Additionally, these EBs were able to more effectively solubilize targets compared to frequently used fusions such as maltose-binding protein, glutathione S-transferase, thioredoxin, and N utilization substance A. Finally, although these EBs possess very distinct physiochemical properties, they did not perturb the structure, conformational stability, or function of the green fluorescent protein or the glutathione S-transferase protein. This work thus illustrates the successful de novo design of intrinsically disordered fusions and presents a promising technology and complementary resource for researchers attempting to solubilize recalcitrant proteins.

  13. Complement inhibitory proteins expression in placentas of thrombophilic women Complement inhibitory proteins expression in placentas of thrombophilic women

    Directory of Open Access Journals (Sweden)

    Przemysław Krzysztof Wirstlein

    2012-10-01

    Full Text Available Factors controlling complement activation appear to exert a protective effect on pregnancy. This is
    particularly important in women with thrombophilia. The aim of this study was to determine the transcript and
    protein levels of complement decay-accelerating factor (DAF and membrane cofactor protein (MCP in the
    placentas of women with acquired and inherited thrombophilia. Also, we assessed immunohistochemistry staining
    of inhibitors of the complement cascade, DAF and MCP proteins, in the placentas of thrombophilic women.
    Placentas were collected from eight women with inherited thrombophilia and ten with acquired thrombophilia.
    The levels of DAF and MCP transcripts were evaluated by qPCR, the protein level was evaluated by Western
    blot. We observed a higher transcript (p < 0.05 and protein (p < 0.001 levels of DAF and MCP in the placentas
    of thrombophilic women than in the control group. DAF and MCP were localized on villous syncytiotrophoblast
    membranes, but the assessment of staining in all groups did not differ. The observed higher expression level of
    proteins that control activation of complement control proteins is only seemingly contradictory to the changes
    observed for example in the antiphospholipid syndrome. However, given the hitherto known biochemical changes
    associated with thrombophilia, a mechanism in which increased expression of DAF and MCP in the placentas is
    an effect of proinflammatory cytokines, which accompanies thrombophilia, is probable.Factors controlling complement activation appear to exert a protective effect on pregnancy. This is
    particularly important in women with thrombophilia. The aim of this study was to determine the transcript and
    protein levels of complement decay-accelerating factor (DAF and membrane cofactor protein (MCP in the
    placentas of women with acquired and inherited thrombophilia. Also, we assessed immunohistochemistry

  14. Expression and/or activity of the SVCT2 ascorbate transporter may be decreased in many aggressive cancers, suggesting potential utility for sodium bicarbonate and dehydroascorbic acid in cancer therapy.

    Science.gov (United States)

    McCarty, Mark F

    2013-10-01

    Hypoxia-inducible factor-1 (HIF-1) is a heterodimer transcription factor whose elevated activity in many cancers helps them to survive under hypoxic conditions and enhances their capacity to grow invasively, establish metastases, and survive chemo- or radiotherapy. Optimal intracellular levels of ascorbate suppress the level and transcriptional activity of HIF-1under normoxic or mildly hypoxic conditions by supporting the activity of proly and asparagyl hydroxylases that target HIF-1alpha. High intracellular ascorbate can also work in various ways to down-regulate activation of NF-kappaB which, like HIF-1 is constitutively active in many cancers and promotes aggressive behavior - in part by promoting transcription of HIF-1alpha. Yet recent evidence suggests that, even in the context of adequate ascorbate nutrition, the intracellular ascorbate content of many aggressive cancers may be supoptimal for effective HIF-1 control. This likely reflects low expression or activity of the SVCT2 ascorbate transporter. The expression of SVCT2 in cancers has so far received little study; but the extracellular acidity characteristic of many tumors would be expected to reduce the activity of this transporter, which has a mildly alkaline pH optimum. Unfortunately, since SVCT2 has a high affinity for ascorbate, and its activity is nearly saturated at normal healthy serum levels of this vitamin, increased oral administration of ascorbate would be unlikely to have much impact on the intracellular ascorbate content of tumors. However, cancers in which HIF-1 is active express high levels of glucose transporters such as GLUT-1, and these transporters can promote influx of dehydroascorbic acid (DHA) via facilitated diffusion; once inside the cell, DHA is rapidly reduced to ascorbate, which effectively is "trapped" within the cell. Hence, episodic intravenous infusions of modest doses of DHA may have potential for optimizing the intracellular ascorbate content of cancers, potentially

  15. Transcript and protein expression profile of PF11_0394, a Plasmodium falciparum protein expressed in salivary gland sporozoites

    Directory of Open Access Journals (Sweden)

    Schlarman Maggie S

    2012-03-01

    Full Text Available Abstract Background Plasmodium falciparum malaria is a significant problem around the world today, thus there is still a need for new control methods to be developed. Because the sporozoite displays dual infectivity for both the mosquito salivary glands and vertebrate host tissue, it is a good target for vaccine development. Methods The P. falciparum gene, PF11_0394, was chosen as a candidate for study due to its potential role in the invasion of host tissues. This gene, which was selected using a data mining approach from PlasmoDB, is expressed both at the transcriptional and protein levels in sporozoites and likely encodes a putative surface protein. Using reverse transcription-polymerase chain reaction (RT-PCR and green fluorescent protein (GFP-trafficking studies, a transcript and protein expression profile of PF11_0394 was determined. Results The PF11_0394 protein has orthologs in other Plasmodium species and Apicomplexans, but none outside of the group Apicomplexa. PF11_0394 transcript was found to be present during both the sporozoite and erythrocytic stages of the parasite life cycle, but no transcript was detected during axenic exoerythrocytic stages. Despite the presence of transcript throughout several life cycle stages, the PF11_0394 protein was only detected in salivary gland sporozoites. Conclusions PF11_0394 appears to be a protein uniquely detected in salivary gland sporozoites. Even though a specific function of PF11_0394 has not been determined in P. falciparum biology, it could be another candidate for a new vaccine.

  16. Identification of differentially expressed serum proteins in gastric adenocarcinoma☆

    Science.gov (United States)

    Subbannayya, Yashwanth; Mir, Sartaj Ahmad; Renuse, Santosh; Manda, Srikanth S.; Pinto, Sneha M.; Puttamallesh, Vinuth N.; Solanki, Hitendra Singh; Manju, H.C.; Syed, Nazia; Sharma, Rakesh; Christopher, Rita; Vijayakumar, M.; Kumar, K.V. Veerendra; Prasad, T.S. Keshava; Ramaswamy, Girija; Kumar, Rekha V.; Chatterjee, Aditi; Pandey, Akhilesh; Gowda, Harsha

    2015-01-01

    Gastric adenocarcinoma is an aggressive cancer with poor prognosis. Blood based biomarkers of gastric cancer have the potential to improve diagnosis and monitoring of these tumors. Proteins that show altered levels in the circulation of gastric cancer patients could prove useful as putative biomarkers. We used an iTRAQ-based quantitative proteomic approach to identify proteins that show altered levels in the sera of patients with gastric cancer. Our study resulted in identification of 643 proteins, of which 48 proteins showed increased levels and 11 proteins showed decreased levels in serum from gastric cancer patients compared to age and sex matched healthy controls. Proteins that showed increased expression in gastric cancer included inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4), Mannose-binding protein C (MBL2), sex hormone-binding globulin (SHBG), insulin-like growth factor-binding protein 2 (IGFBP2), serum amyloid A protein (SAA1), Orosomucoid 1 (ORM1) and extracellular superoxide dismutase [Cu–Zn] (SOD3). We used multiple reaction monitoring assays and validated elevated levels of ITIH4 and SAA1 proteins in serum from gastric cancer patients. Biological significance Gastric cancer is a highly aggressive cancer associated with high mortality. Serum-based biomarkers are of considerable interest in diagnosis and monitoring of various diseases including cancers. Gastric cancer is often diagnosed at advanced stages resulting in poor prognosis and high mortality. Pathological diagnosis using biopsy specimens remains the gold standard for diagnosis of gastric cancer. Serum-based biomarkers are of considerable importance as they are minimally invasive. In this study, we carried out quantitative proteomic profiling of serum from gastric cancer patients to identify proteins that show altered levels in gastric cancer patients. We identified more than 50 proteins that showed altered levels in gastric cancer patient sera. Validation in a large cohort of well

  17. Expression of P53 protein after exposure to ionizing radiation

    Science.gov (United States)

    Salazar, A. M.; Salvador, C.; Ruiz-Trejo, C.; Ostrosky, P.; Brandan, M. E.

    2001-10-01

    One of the most important tumor suppressor genes is p53 gene, which is involved in apoptotic cell death, cell differentiation and cell cycle arrest. The expression of p53 gene can be evaluated by determining the presence of P53 protein in cells using Western Blot assay with a chemiluminescent method. This technique has shown variabilities that are due to biological factors. Film developing process can influence the quality of the p53 bands obtained. We irradiated tumor cell lines and human peripheral lymphocytes with 137Cs and 60Co gamma rays to standardize irradiation conditions, to compare ionizing radiation with actinomycin D and to reduce the observed variability of P53 protein induction levels. We found that increasing radiation doses increase P53 protein induction while it decreases viability. We also conclude that ionizing radiation could serve as a positive control for Western Blot analysis of protein P53. In addition, our results show that the developing process may play an important role in the quality of P53 protein bands and data interpretation.

  18. A molecular clock regulates angiopoietin-like protein 2 expression.

    Science.gov (United States)

    Kadomatsu, Tsuyoshi; Uragami, Shota; Akashi, Makoto; Tsuchiya, Yoshiki; Nakajima, Hiroo; Nakashima, Yukiko; Endo, Motoyoshi; Miyata, Keishi; Terada, Kazutoyo; Todo, Takeshi; Node, Koichi; Oike, Yuichi

    2013-01-01

    Various physiological and behavioral processes exhibit circadian rhythmicity. These rhythms are usually maintained by negative feedback loops of core clock genes, namely, CLOCK, BMAL, PER, and CRY. Recently, dysfunction in the circadian clock has been recognized as an important foundation for the pathophysiology of lifestyle-related diseases, such as obesity, cardiovascular disease, and some cancers. We have reported that angiopoietin-like protein 2 (ANGPTL2) contributes to the pathogenesis of these lifestyle-related diseases by inducing chronic inflammation. However, molecular mechanisms underlying regulation of ANGPTL2 expression are poorly understood. Here, we assess circadian rhythmicity of ANGPTL2 expression in various mouse tissues. We observed that ANGPTL2 rhythmicity was similar to that of the PER2 gene, which is regulated by the CLOCK/BMAL1 complex. Promoter activity of the human ANGPTL2 gene was significantly induced by CLOCK and BMAL1, an induction markedly attenuated by CRY co-expression. We also identified functional E-boxes in the ANGPTL2 promoter and observed occupancy of these sites by endogenous CLOCK in human osteosarcoma cells. Furthermore, Cry-deficient mice exhibited arrhythmic Angptl2 expression. Taken together, these data suggest that periodic expression of ANGPTL2 is regulated by a molecular clock.

  19. A molecular clock regulates angiopoietin-like protein 2 expression.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Kadomatsu

    Full Text Available Various physiological and behavioral processes exhibit circadian rhythmicity. These rhythms are usually maintained by negative feedback loops of core clock genes, namely, CLOCK, BMAL, PER, and CRY. Recently, dysfunction in the circadian clock has been recognized as an important foundation for the pathophysiology of lifestyle-related diseases, such as obesity, cardiovascular disease, and some cancers. We have reported that angiopoietin-like protein 2 (ANGPTL2 contributes to the pathogenesis of these lifestyle-related diseases by inducing chronic inflammation. However, molecular mechanisms underlying regulation of ANGPTL2 expression are poorly understood. Here, we assess circadian rhythmicity of ANGPTL2 expression in various mouse tissues. We observed that ANGPTL2 rhythmicity was similar to that of the PER2 gene, which is regulated by the CLOCK/BMAL1 complex. Promoter activity of the human ANGPTL2 gene was significantly induced by CLOCK and BMAL1, an induction markedly attenuated by CRY co-expression. We also identified functional E-boxes in the ANGPTL2 promoter and observed occupancy of these sites by endogenous CLOCK in human osteosarcoma cells. Furthermore, Cry-deficient mice exhibited arrhythmic Angptl2 expression. Taken together, these data suggest that periodic expression of ANGPTL2 is regulated by a molecular clock.

  20. Prion protein expression regulates embryonic stem cell pluripotency and differentiation.

    Directory of Open Access Journals (Sweden)

    Alberto Miranda

    Full Text Available Cellular prion protein (PRNP is a glycoprotein involved in the pathogenesis of transmissible spongiform encephalopathies (TSEs. Although the physiological function of PRNP is largely unknown, its key role in prion infection has been extensively documented. This study examines the functionality of PRNP during the course of embryoid body (EB differentiation in mouse Prnp-null (KO and WT embryonic stem cell (ESC lines. The first feature observed was a new population of EBs that only appeared in the KO line after 5 days of differentiation. These EBs were characterized by their expression of several primordial germ cell (PGC markers until Day 13. In a comparative mRNA expression analysis of genes playing an important developmental role during ESC differentiation to EBs, Prnp was found to participate in the transcription of a key pluripotency marker such as Nanog. A clear switching off of this gene on Day 5 was observed in the KO line as opposed to the WT line, in which maximum Prnp and Nanog mRNA levels appeared at this time. Using a specific antibody against PRNP to block PRNP pathways, reduced Nanog expression was confirmed in the WT line. In addition, antibody-mediated inhibition of ITGB5 (integrin αvβ5 in the KO line rescued the low expression of Nanog on Day 5, suggesting the regulation of Nanog transcription by Prnp via this Itgb5. mRNA expression analysis of the PRNP-related proteins PRND (Doppel and SPRN (Shadoo, whose PRNP function is known to be redundant, revealed their incapacity to compensate for the absence of PRNP during early ESC differentiation. Our findings provide strong evidence for a relationship between Prnp and several key pluripotency genes and attribute Prnp a crucial role in regulating self-renewal/differentiation status of ESC, confirming the participation of PRNP during early embryogenesis.

  1. Glycolipid transfer protein expression is affected by glycosphingolipid synthesis.

    Directory of Open Access Journals (Sweden)

    Matti A Kjellberg

    Full Text Available Members of the glycolipid transfer protein superfamily (GLTP are found from animals and fungi to plants and red micro-alga. Eukaryotes that encode the glucosylceramide synthase responsible for the synthesis of glucosylceramide, the precursor for most glycosphingolipids, also produce GLTPs. Cells that does not synthesize glucosylceramide neither express GLTPs. Based on this genetic relationship there must be a strong correlation between the synthesis of glucosylceramide and GLTPs. To regulate the levels of glycolipids we have used inhibitors of intracellular trafficking, glycosphingolipid synthesis and degradation, and small interfering RNA to down-regulate the activity of glucosylceramide synthase activity. We found that GLTP expression, both at the mRNA and protein levels, is elevated in cells that accumulate glucosylceramide. Monensin and brefeldin A block intracellular vesicular transport mechanisms. Brefeldin A treatment leads to accumulation of newly synthesized glucosylceramide, galactosylceramide and lactosylceramide in a fused endoplasmic reticulum-Golgi complex. On the other hand, inhibiting glycosphingolipid degradation with conduritol-B-epoxide, that generates glucosylceramide accumulation in the lysosomes, did not affect the levels of GLTP. However, glycosphingolipid synthesis inhibitors like PDMP, NB-DNJ and myriocin, all decreased glucosylceramide and GLTP below normal levels. We also found that an 80% loss of glucosylceramide due to glucosylceramide synthase knockdown resulted in a significant reduction in the expression of GLTP. We show here that interfering with membrane trafficking events and simple neutral glycosphingolipid synthesis will affect the expression of GLTP. We postulate that a change in the glucosylceramide balance causes a response in the GLTP expression, and put forward that GLTP might play a role in lipid directing and sensing of glucosylceramide at the ER-Golgi interface.

  2. Common and specific signatures of gene expression and protein-protein interactions in autoimmune diseases.

    Science.gov (United States)

    Tuller, T; Atar, S; Ruppin, E; Gurevich, M; Achiron, A

    2013-03-01

    The aim of this study is to understand intracellular regulatory mechanisms in peripheral blood mononuclear cells (PBMCs), which are either common to many autoimmune diseases or specific to some of them. We incorporated large-scale data such as protein-protein interactions, gene expression and demographical information of hundreds of patients and healthy subjects, related to six autoimmune diseases with available large-scale gene expression measurements: multiple sclerosis (MS), systemic lupus erythematosus (SLE), juvenile rheumatoid arthritis (JRA), Crohn's disease (CD), ulcerative colitis (UC) and type 1 diabetes (T1D). These data were analyzed concurrently by statistical and systems biology approaches tailored for this purpose. We found that chemokines such as CXCL1-3, 5, 6 and the interleukin (IL) IL8 tend to be differentially expressed in PBMCs of patients with the analyzed autoimmune diseases. In addition, the anti-apoptotic gene BCL3, interferon-γ (IFNG), and the vitamin D receptor (VDR) gene physically interact with significantly many genes that tend to be differentially expressed in PBMCs of patients with the analyzed autoimmune diseases. In general, similar cellular processes tend to be differentially expressed in PBMC in the analyzed autoimmune diseases. Specifically, the cellular processes related to cell proliferation (for example, epidermal growth factor, platelet-derived growth factor, nuclear factor-κB, Wnt/β-catenin signaling, stress-activated protein kinase c-Jun NH2-terminal kinase), inflammatory response (for example, interleukins IL2 and IL6, the cytokine granulocyte-macrophage colony-stimulating factor and the B-cell receptor), general signaling cascades (for example, mitogen-activated protein kinase, extracellular signal-regulated kinase, p38 and TRK) and apoptosis are activated in most of the analyzed autoimmune diseases. However, our results suggest that in each of the analyzed diseases, apoptosis and chemotaxis are activated via

  3. Dynamic expression pattern of kinesin accessory protein in Drosophila

    Indian Academy of Sciences (India)

    Ritu Sarpal; Krishanu Ray

    2002-09-01

    We have identified the Drosophila homologue of the non-motor accessory subunit of kinesin-II motor complex. It is homologous to the SpKAP115 of the sea urchin, KAP3A and KAP3B of the mouse, and SMAP protein in humans. In situ hybridization using a DmKAP specific cRNA probe has revealed a dynamic pattern of expression in the developing nervous system. The staining first appears in a subset of cells in the embryonic central nervous system at stage 13 and continues till the first instar larva stage. At the third instar larva stage the staining gets restricted to a few cells in the optic lobe and in the ventral ganglion region. It has also stained a subset of sensory neurons from late stage 13 and till the first instar larva stage. The DmKAP expression pattern in the nervous system corresponds well with that of Klp64D and Klp68D as reported earlier. In addition, we have found that the DmKAP gene is constitutively expressed in the germline cells and in follicle cells during oogenesis. These cells are also stained using an antibody to KLP68D protein, but mRNA in situ hybridization using KLP64D specific probe has not stained these cells. Together these results proved a basis for further analysis of tissue specific function of DmKAP in future.

  4. Ribosomal protein S6 associates with alphavirus nonstructural protein 2 and mediates expression from alphavirus messages.

    Science.gov (United States)

    Montgomery, Stephanie A; Berglund, Peter; Beard, Clayton W; Johnston, Robert E

    2006-08-01

    Although alphaviruses dramatically alter cellular function within hours of infection, interactions between alphaviruses and specific host cellular proteins are poorly understood. Although the alphavirus nonstructural protein 2 (nsP2) is an essential component of the viral replication complex, it also has critical auxiliary functions that determine the outcome of infection in the host. To gain a better understanding of nsP2 function, we sought to identify cellular proteins with which Venezuelan equine encephalitis virus nsP2 interacted. We demonstrate here that nsP2 associates with ribosomal protein S6 (RpS6) and that nsP2 is present in the ribosome-containing fractions of a polysome gradient, suggesting that nsP2 associates with RpS6 in the context of the whole ribosome. This result was noteworthy, since viral replicase proteins have seldom been described in direct association with components of the ribosome. The association of RpS6 with nsP2 was detected throughout the course of infection, and neither the synthesis of the viral structural proteins nor the presence of the other nonstructural proteins was required for RpS6 interaction with nsP2. nsP1 also was associated with RpS6, but other nonstructural proteins were not. RpS6 phosphorylation was dramatically diminished within hours after infection with alphaviruses. Furthermore, a reduction in the level of RpS6 protein expression led to diminished expression from alphavirus subgenomic messages, whereas no dramatic diminution in cellular translation was observed. Taken together, these data suggest that alphaviruses alter the ribosome during infection and that this alteration may contribute to differential translation of host and viral messages.

  5. Expression of mammalian DT-diaphorase in Escherichia coli: purification and characterization of the expressed protein.

    Science.gov (United States)

    Ma, Q; Wang, R; Yang, C S; Lu, A Y

    1990-12-01

    A full-length cDNA clone, pKK-DTD4, complementary to rat liver cytosolic DT-diaphorase [NAD(P)H:quinone oxidoreductase (EC 1.6.99.2)] mRNA was expressed in Escherichia coli. The pKK-DTD4 cDNA was obtained by extending the 5'-end sequence of a rat liver DT-diaphorase cDNA clone, pDTD55, to include an ATG initiation codon and the NH2-terminal codons using polymerase chain reaction (PCR). Restriction sites for EcoRI and HindIII were incorporated at the 5'- and 3'-ends of the cDNA, respectively, by the PCR reaction. The resulting full-length cDNA was inserted into an expression vector, pKK2.7, at the EcoRI and HindIII restriction sites. E. coli strain AB1899 was transformed with the constructed expression plasmid, and DT-diaphorase was expressed under the control of the tac promotor. The expressed DT-diaphorase exhibited high activity of menadione reduction and was inhibited by dicumarol at a concentration of 10(-5)M. After purification by Cibacron Blue affinity chromatography, the expressed enzyme migrated as a single band on 12.5% sodium dodecyl sulfate-polyacrylamide gel with a molecular weight equivalent to that of the purified rat liver cytosolic DT-diaphorase. The purified expressed protein was recognized by polyclonal antibodies against rat liver DT-diaphorase on immunoblot analysis. It utilized either NADPH or NADH as electron donor at equal efficiency and displayed high activities in reduction of menadione, 1,4-benzoquinone, and 2,6-dichlorophenolindophenol which are typical substrates for DT-diaphorase. The expressed DT-diaphorase exhibited a typical flavoprotein spectrum with absorption peaks at 380 and 452 nm. Flavin content determination showed that it contained 2 mol of FAD per mole of the enzyme. Edman protein sequencing of the first 20 amino acid residues at the NH2 terminus of the expressed protein indicated that the expressed DT-diaphorase is not blocked at the NH2 terminus and has an alanine as the first amino acid. The remaining 19 amino acid

  6. Identification of differentially expressed proteins and phosphorylated proteins in rice seedlings in response to strigolactone treatment.

    Directory of Open Access Journals (Sweden)

    Fangyu Chen

    Full Text Available Strigolactones (SLs are recently identified plant hormones that inhibit shoot branching and control various aspects of plant growth, development and interaction with parasites. Previous studies have shown that plant D10 protein is a carotenoid cleavage dioxygenase that functions in SL biosynthesis. In this work, we used an allelic SL-deficient d10 mutant XJC of rice (Oryza sativa L. spp. indica to investigate proteins that were responsive to SL treatment. When grown in darkness, d10 mutant seedlings exhibited elongated mesocotyl that could be rescued by exogenous application of SLs. Soluble protein extracts were prepared from d10 mutant seedlings grown in darkness in the presence of GR24, a synthetic SL analog. Soluble proteins were separated on two-dimensional gels and subjected to proteomic analysis. Proteins that were expressed differentially and phosphoproteins whose phosphorylation status changed in response to GR24 treatment were identified. Eight proteins were found to be induced or down-regulated by GR24, and a different set of 8 phosphoproteins were shown to change their phosphorylation intensities in the dark-grown d10 seedlings in response to GR24 treatment. Analysis of these proteins revealed that they are important enzymes of the carbohydrate and amino acid metabolic pathways and key components of the cellular energy generation machinery. These proteins may represent potential targets of the SL signaling pathway. This study provides new insight into the complex and negative regulatory mechanism by which SLs control shoot branching and plant development.

  7. Structure and expression of a novel compact myelin protein – Small VCP-interacting protein (SVIP)

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jiawen [Department of Neurology, Vanderbilt University School of Medicine (United States); Peng, Dungeng [Department of Biochemistry, Vanderbilt University School of Medicine (United States); Voehler, Markus [Center for Structural Biology, Vanderbilt University (United States); Sanders, Charles R. [Department of Biochemistry, Vanderbilt University School of Medicine (United States); Center for Structural Biology, Vanderbilt University (United States); Li, Jun, E-mail: jun.li.2@vanderbilt.edu [Department of Neurology, Vanderbilt University School of Medicine (United States); Tennessee Valley Healthcare System (TVHS) – Nashville VA (United States)

    2013-10-11

    Highlights: •SVIP (small p97/VCP-interacting protein) co-localizes with myelin basic protein (MBP) in compact myelin. •We determined that SVIP is an intrinsically disordered protein (IDP). •The helical content of SVIP increases dramatically during its interaction with negatively charged lipid membrane. •This study provides structural insight into interactions between SVIP and myelin membranes. -- Abstract: SVIP (small p97/VCP-interacting protein) was initially identified as one of many cofactors regulating the valosin containing protein (VCP), an AAA+ ATPase involved in endoplasmic-reticulum-associated protein degradation (ERAD). Our previous study showed that SVIP is expressed exclusively in the nervous system. In the present study, SVIP and VCP were seen to be co-localized in neuronal cell bodies. Interestingly, we also observed that SVIP co-localizes with myelin basic protein (MBP) in compact myelin, where VCP was absent. Furthermore, using nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopic measurements, we determined that SVIP is an intrinsically disordered protein (IDP). However, upon binding to the surface of membranes containing a net negative charge, the helical content of SVIP increases dramatically. These findings provide structural insight into interactions between SVIP and myelin membranes.

  8. Functional analysis of expressed peptides that bind yeast STE proteins.

    Science.gov (United States)

    Caponigro, Giordano; Abedi, Majid; Kamb, Alexander

    2003-08-15

    Peptides are potentially useful for target validation and other reverse genetic applications. For instance, if a specific protein is susceptible to peptide inhibition, it may have a higher probability of being vulnerable to small molecules. We used the yeast two-hybrid technique to identify and study peptide binders for three yeast proteins involved in pheromone response: Ste11p, Ste18p, and Ste50p. A subset of peptide binders was shown to inhibit pheromone response in cells using two different functional assays. In addition, we utilized a variant of the yeast two-hybrid method to examine relative binding affinities based on competitive interactions in yeast. Our results suggest that binding affinity and inhibitory potency of peptides do not correlate perfectly and that peptide-protein interactions can be complex and unpredictable. Taken together these results suggest that while peptides are useful as in vivo inhibitors of protein function, caution must be exercised when choosing peptides for further studies and when inferring affinities from expression phenotypes.

  9. Measuring ERCC1 protein expression in cancer specimens

    DEFF Research Database (Denmark)

    Smith, David Hersi; Fiehn, Anne-Marie Kanstrup; Fogh, Louise

    2014-01-01

    Platinum chemotherapy remains part of standard therapies in the management of a variety of cancers. Severe side effects and a high degree of resistance to platinum drugs have led numerous researchers to search for predictive biomarkers, which could aid in identifying patients that are the most...... likely to respond to therapy. The ERCC1-ERCC4 endonuclease plays a critical role in the repair of platinum-DNA damage and has widely been studied in relation to sensitivity to platinum chemotherapy. The standard method to evaluate ERCC1 protein expression is through the use of immunohistochemistry...

  10. Expressed protein ligation for metalloprotein design and engineering.

    Science.gov (United States)

    Clark, Kevin M; van der Donk, Wilfred A; Lu, Yi

    2009-01-01

    Metalloproteins contain highly specialized metal-binding sites that are designed to accept specific metal ions to maintain correct function. Although many of the sites have been modified with success, the relative paucity of functional group availability within proteinogenic amino acids can sometimes leave open questions about specific functions of the metal binding ligands. Attaining a more thorough analysis of individual amino acid function within metalloproteins has been realized using expressed protein ligation (EPL). Here we describe our recent efforts using EPL to incorporate nonproteinogenic cysteine and methionine analogues into the type 1 copper site found in Pseudomonas aeruginosa azurin.

  11. Complexity of Gene Expression Evolution after Duplication: Protein Dosage Rebalancing

    Directory of Open Access Journals (Sweden)

    Igor B. Rogozin

    2014-01-01

    Full Text Available Ongoing debates about functional importance of gene duplications have been recently intensified by a heated discussion of the “ortholog conjecture” (OC. Under the OC, which is central to functional annotation of genomes, orthologous genes are functionally more similar than paralogous genes at the same level of sequence divergence. However, a recent study challenged the OC by reporting a greater functional similarity, in terms of gene ontology (GO annotations and expression profiles, among within-species paralogs compared to orthologs. These findings were taken to indicate that functional similarity of homologous genes is primarily determined by the cellular context of the genes, rather than evolutionary history. Subsequent studies suggested that the OC appears to be generally valid when applied to mammalian evolution but the complete picture of evolution of gene expression also has to incorporate lineage-specific aspects of paralogy. The observed complexity of gene expression evolution after duplication can be explained through selection for gene dosage effect combined with the duplication-degeneration-complementation model. This paper discusses expression divergence of recent duplications occurring before functional divergence of proteins encoded by duplicate genes.

  12. Increased heat shock protein expression after stress in Japanese quail.

    Science.gov (United States)

    Hoekstra, K A; Iwama, G K; Nichols, C R; Godin, D V; Cheng, K M

    1998-12-01

    Heat shock proteins (HSPs) have been shown to provide information on the biological impact of environmental stress to organisms, yet none have investigated the HSP response to stress in birds. Japanese quail were exposed to seven different stressors (mild restraint, loud noise, inescapable irritation, cold temperature, isolation in darkness, and two stressful social situations) and expression of HSP30, 60, 70, and 90 in heart, liver, lung, kidney and gonads was examined. Tonic Immobility (TI) tests were also conducted to assess whether the stressors increased fear response. Increased expression of HSP70 was found in the myocardial tissue of birds exposed to loud noise, inescapable irritation, cold temperature, and isolation in darkness. Increased expression of other HSPs was not apparent in the heart or any of the other all tissues examined. Longer TI was observed only in birds exposed to the noise stress. Evidence is presented that a fairly wide range of stressors caused increased expression of HSP70 in the Japanese quail myocardial tissue and that HSPs may provide useful biomarkers for the study of environmental stress in birds.

  13. Differential regulation of dentin matrix protein 1 expression during odontogenesis.

    Science.gov (United States)

    Lu, Yongbo; Zhang, Shubin; Xie, Yixia; Pi, Yuli; Feng, Jian Q

    2005-01-01

    Dentin matrix protein 1 (DMP1) is highly expressed in mineralized tooth and bone. Both in vitro and in vivo data show that DMP1 is critical for mineralization and tooth morphogenesis (growth and development). In this study, we studied Dmp1 gene regulation. The in vitro transient transfection assay identified two important DNA fragments, the 2.4- and 9.6-kb promoter regions. We next generated and analyzed transgenic mice bearing the beta-galactosidase (lacZ) reporter gene driven by the 2.4- or 9.6-kb promoter with the complete 4-kb intron 1. The 9.6-kb Dmp1-lacZ mice conferred a DMP1 expression pattern in odontoblasts identical to that in the endogenous Dmp1 gene. This is reflected by lacZ expression in Dmp1-lacZ knock-in mice during all stages of odontogenesis. In contrast, the 2.4-kb Dmp1-lacZ mice display activity in odontoblast cells only at the early stage of odontogenesis. Thus, we propose that different transcription factors regulate early or later cis-regulatory domains of the Dmp1 promoter, which gives rise to the unique spatial and temporal expression pattern of Dmp1 gene at different stages of tooth development. 2005 S. Karger AG, Basel

  14. Expression of goose parvovirus whole VP3 protein and its epitopes in Escherichia coli cells.

    Science.gov (United States)

    Tarasiuk, K; Woźniakowski, G; Holec-Gąsior, L

    2015-01-01

    The aim of this study was the expression of goose parvovirus capsid protein (VP3) and its epitopes in Escherichia coli cells. Expression of the whole VP3 protein provided an insufficient amount of protein. In contrast, the expression of two VP3 epitopes (VP3ep4, VP3ep6) in E. coli, resulted in very high expression levels. This may suggest that smaller parts of the GPV antigenic determinants are more efficiently expressed than the complete VP3 gene.

  15. Sperm protein 17 is expressed in human nervous system tumours

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    Frezza Eldo E

    2006-01-01

    Full Text Available Abstract Background Human sperm protein 17 (Sp17 is a highly conserved protein that was originally isolated from a rabbit epididymal sperm membrane and testis membrane pellet. It has recently been included in the cancer/testis (CT antigen family, and shown to be expressed in multiple myeloma and ovarian cancer. We investigated its immunolocalisation in specimens of nervous system (NS malignancies, in order to establish its usefulness as a target for tumour-vaccine strategies. Methods The expression of Sp17 was assessed by means of a standardised immunohistochemical procedure [(mAb/antigen MF1/Sp17] in formalin-fixed and paraffin embedded surgical specimens of NS malignancies, including 28 neuroectodermal primary tumours (6 astrocytomas, 16 glioblastoma multiforme, 5 oligodendrogliomas, and 1 ependymoma, 25 meningeal tumours, and five peripheral nerve sheath tumours (4 schwannomas, and 1 neurofibroma,. Results A number of neuroectodermal (21% and meningeal tumours (4% were found heterogeneously immunopositive for Sp17. None of the peripheral nerve sheath tumours was immunopositive for Sp17. The expression pattern was heterogeneous in all of the positive samples, and did not correlate with the degree of malignancy. Conclusion The frequency of expression and non-uniform cell distribution of Sp17 suggest that it cannot be used as a unique immunotherapeutic target in NS cancer. However, our results do show the immunolocalisation of Sp17 in a proportion of NS tumour cells, but not in their non-pathological counterparts. The emerging complex function of Sp17 makes further studies necessary to clarify the link between it and immunopositive cells.

  16. Analysis of cDNA sequence, protein structure and expression of parotid secretory protein in pig

    Institute of Scientific and Technical Information of China (English)

    YIN Haifang; FAN Baoliang; ZHAO Zhihui; LIU Zhaoliang; FEI Jing; LI Ning

    2003-01-01

    Parotid secretory protein (PSP) secreted abundantly in saliva, whose function is related with the anti-bacterial effect. The PSP cDNA has been isolated from pig parotid glands by 3′ and 5′ rapid amplification of cDNA end (RACE),based on the conserved signal peptide region among the known mammalian PSP. Theresult of homologous comparison shows that pig PSP and human PSP shares the high identity at the level of the primary, secondary and tertiary protein structure. A search for functionally significant protein motifs revealed a unique amino acid sequence pattern consisting of the residues Leu-X(6)-Leu-X(6)-Leu- X(7)-Leu-X(6)-Leu-X(6)-Leu near the amino-terminal portion of the protein, which is important to its function. RT-PCR, Dot blot and Northern blot analysis demonstrated that PSP was strongly expressed in parotid glands, but not in other tissues.

  17. Up-regulation of hypoxia-inducible factor (HIF)-1α and HIF-target genes in cortical neurons by the novel multifunctional iron chelator anti-Alzheimer drug, M30.

    Science.gov (United States)

    Avramovich-Tirosh, Y; Bar-Am, O; Amit, T; Youdim, M B H; Weinreb, O

    2010-06-01

    Based on a multimodal drug design paradigm, we have synthesized a multifunctional non-toxic, brain permeable iron chelator, M30, possessing the neuroprotective propargylamine moiety of the anti-Parkinsonian drug, rasagiline (Azilect) and antioxidant-iron chelator moiety of an 8-hydroxyquinoline derivative of our iron chelator, VK28. M30 was recently found to confer potential neuroprotective effects in vitro and in various preclinical neurodegenerative models and regulate the levels and processing of the Alzheimer's amyloid precursor protein and its toxic amyloidogenic derivative, Abeta. Here, we show that M30 activates the hypoxia-inducible factor (HIF)-1alpha signaling pathway, thus promoting HIF-1alpha mRNA and protein expression levels, as well as increasing transcription of HIF-1alpha-dependent genes, including vascular endothelial growth factor, erythropoietin, enolase-1, p21 and tyrosine hydroxylase in rat primary cortical cells. In addition, M30 also increased the expression levels of the transcripts of brain derived neurotrophic factor (BDNF) and growth-associated protein-43 (GAP-43). Regarding aspects of relevance to Alzheimer's disease (AD), western blotting analysis of glycogen synthase kinase- 3beta (GSK-3beta) signaling pathway revealed that M30 enhanced the levels of phospho-AKT (Ser473) and phospho- GSK-3beta (Ser9) and attenuated Tau phosphorylation. M30 was also shown to protect cultured cortical neurons against Abeta(25-35) toxicity. All these multimodal pharmacological activities of M30 might be beneficial for its potent efficacy in the prevention and treatment of neurodegenerative conditions, such as Parkinson's disease and AD in which oxidative stress and iron-mediated toxicity are involved.

  18. Down-expression of tumor protein p53-induced nuclear protein 1 in human gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Pei-Hong Jiang; Yoshiharu Motoo; Stéphane Garcia; Juan Lucio Iovanna; Marie-Josèphe Pébusque; Norio Sawabu

    2006-01-01

    AIM: Overexpression of tumor protein p53-induced nuclear protein 1 (TP53INP1) induces G1 cell cycle arrest and increases p53-mediated apoptosis. To clarify the clinical importance of TP53INP1, we analyzed TP53INP1and p53 expression in gastric cancer.METHODS: TP53INP1 and p53 expression were examined using immunohistochemistry in 142 cases of gastric cancer. The apoptosis of gastric cancer cells was analyzed using the TUNEL method. The relationship between the expression of TP53INP1 and clinicopathological factors was statistically analyzed.RESULTS: TP53INP1 was expressed in 98% (139/142cases) of non-cancerous gastric tissues and was downexpressed in 64% (91/142 cases) of gastric cancer lesions from the same patients. TP53INP1 expression was significantly decreased (43.9%) in poorly differentiated adenocarcinoma compared with well or moderately differentiated adenocarcinoma (81.6%).Cancers invading the submucosa or deeper showed lower positively (59.1%) compared with mucosal cancers (85.2%). Decrease or loss of TP53INP1 expression was significantly correlated with lymphatic invasion (54.3%vs 82.0% without lymphatic invasion) and node-positive patients (31.3% vs 68.3% in node-negative patients).P53 was expressed in 68 (47.9%) patients of gastric cancer, whereas it was absent in normal gastric tissues.A significant association was also observed between TP53INP1 status and the level of apoptosis in tumor cells: the apoptotic index in TP53INP1-positive tissues was significantly higher than that in TP53INP1-negative portions. Finally, when survival data were analyzed,loss of TP53INP1 expression had a significant effect in predicting a poor prognosis (P= 0.0006).CONCLUSION: TP53INP1-positive rate decreases with the progression of gastric cancer. TP53INP1 protein negativity is significantly associated with aggressive pathological phenotypes of gastric cancer. TP53INP1is related to the apoptosis of gastric cancer cells. The decreased expression of the TP53INP1 protein may

  19. Antigenic assessment of a recombinant human CD90 protein expressed in prokaryotic expression system.

    Science.gov (United States)

    Yousefi-Rad, Narges; Shokrgozar, Mohammad Ali; Behdani, Mahdi; Moradi-Kalbolandi, Shima; Motamedi-Rad, Mahdieh; Habibi-Anbouhi, Mahdi

    2015-12-01

    Cluster of Differentiation 90 (CD90, Thy-1) has been proposed as one of the most important biomarkers in several cancer cells including cancer stem cells (CSCs). CD90 is considered as a potential normal stem cell and CSCs biomarker and also has been identified in lung cancer stem cells, hepatocellular carcinoma cells and high-grade gliomas. Using eukaryotic host systems involves complex procedures and frequently results in low protein yields. The expression of recombinant proteins in Escherichia coli is comparatively easier than eukaryotic host cells. The potential of large scale production of recombinant protein has made this system an economic production platform. In this study we expressed the extra-membrane domain of human CD90 (exCD90) antigen (Gln15-Cys130) in E. coli expression host cells. The epitope integrity of purified recombinant antigen was confirmed by antibody-antigen interaction using 5E10 anti-CD90 monoclonal antibody and binding study through ELISA and florescent staining of CD90(+) cells in a flow cytometry experiment. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Expression and the antigenicity of recombinant coat proteins of tungro viruses expressed in Escherichia coli.

    Science.gov (United States)

    Yee, Siew Fung; Chu, Chia Huay; Poili, Evenni; Sum, Magdline Sia Henry

    2017-02-01

    Rice tungro disease (RTD) is a recurring disease affecting rice farming especially in the South and Southeast Asia. The disease is commonly diagnosed by visual observation of the symptoms on diseased plants in paddy fields and by polymerase chain reaction (PCR). However, visual observation is unreliable and PCR can be costly. High-throughput as well as relatively cheap detection methods are important for RTD management for screening large number of samples. Due to this, detection by serological assays such as immunoblotting assays and enzyme-linked immunosorbent assay are preferred. However, these serological assays are limited by lack of continuous supply of antibodies as reagents due to the difficulty in preparing sufficient purified virions as antigens. This study aimed to generate and evaluate the reactivity of the recombinant coat proteins of Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV) as alternative antigens to generate antibodies. The genes encoding the coat proteins of both viruses, RTBV (CP), and RTSV (CP1, CP2 and CP3) were cloned and expressed as recombinant fusion proteins in Escherichia coli. All of the recombinant fusion proteins, with the exception of the recombinant fusion protein of the CP2 of RTSV, were reactive against our in-house anti-tungro rabbit serum. In conclusion, our study showed the potential use of the recombinant fusion coat proteins of the tungro viruses as alternative antigens for production of antibodies for diagnostic purposes.

  1. Expression and purification of recombinant polyomavirus VP2 protein and its interactions with polyomavirus proteins

    Science.gov (United States)

    Cai, X.; Chang, D.; Rottinghaus, S.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Recombinant polyomavirus VP2 protein was expressed in Escherichia coli (RK1448), using the recombinant expression system pFPYV2. Recombinant VP2 was purified to near homogeneity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroelution, and Extracti-Gel chromatography. Polyclonal serum to this protein which reacted specifically with recombinant VP2 as well as polyomavirus virion VP2 and VP3 on Western blots (immunoblots) was produced. Purified VP2 was used to establish an in vitro protein-protein interaction assay with polyomavirus structural proteins and purified recombinant VP1. Recombinant VP2 interacted with recombinant VP1, virion VP1, and the four virion histones. Recombinant VP1 coimmunoprecipitated with recombinant VP2 or truncated VP2 (delta C12VP2), which lacked the carboxy-terminal 12 amino acids. These experiments confirmed the interaction between VP1 and VP2 and revealed that the carboxyterminal 12 amino acids of VP2 and VP3 were not necessary for formation of this interaction. In vivo VP1-VP2 interaction study accomplished by cotransfection of COS-7 cells with VP2 and truncated VP1 (delta N11VP1) lacking the nuclear localization signal demonstrated that VP2 was capable of translocating delta N11VP1 into the nucleus. These studies suggest that complexes of VP1 and VP2 may be formed in the cytoplasm and cotransported to the nucleus for virion assembly to occur.

  2. Growing functional modules from a seed protein via integration of protein interaction and gene expression data

    Directory of Open Access Journals (Sweden)

    Dimitrakopoulou Konstantina

    2007-10-01

    Full Text Available Abstract Background Nowadays modern biology aims at unravelling the strands of complex biological structures such as the protein-protein interaction (PPI networks. A key concept in the organization of PPI networks is the existence of dense subnetworks (functional modules in them. In recent approaches clustering algorithms were applied at these networks and the resulting subnetworks were evaluated by estimating the coverage of well-established protein complexes they contained. However, most of these algorithms elaborate on an unweighted graph structure which in turn fails to elevate those interactions that would contribute to the construction of biologically more valid and coherent functional modules. Results In the current study, we present a method that corroborates the integration of protein interaction and microarray data via the discovery of biologically valid functional modules. Initially the gene expression information is overlaid as weights onto the PPI network and the enriched PPI graph allows us to exploit its topological aspects, while simultaneously highlights enhanced functional association in specific pairs of proteins. Then we present an algorithm that unveils the functional modules of the weighted graph by expanding a kernel protein set, which originates from a given 'seed' protein used as starting-point. Conclusion The integrated data and the concept of our approach provide reliable functional modules. We give proofs based on yeast data that our method manages to give accurate results in terms both of structural coherency, as well as functional consistency.

  3. Trichohyalin-like 1 protein, a member of fused S100 proteins, is expressed in normal and pathologic human skin

    Energy Technology Data Exchange (ETDEWEB)

    Yamakoshi, Takako [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Makino, Teruhiko, E-mail: tmakino@med.u-toyama.ac.jp [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Ur Rehman, Mati; Yoshihisa, Yoko [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Sugimori, Michiya [Department of Integrative Neuroscience, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Shimizu, Tadamichi, E-mail: shimizut@med.u-toyama.ac.jp [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan)

    2013-03-01

    Highlights: ► Trichohyalin-like 1 protein is a member of the fused-type S100 protein gene family. ► Specific antibodies against the C-terminus of the TCHHL1 protein were generated. ► TCHHL1 proteins were expressed in the basal layer of the normal epidermis. ► TCHHL1 proteins were strongly expressed in tumor nests of BCC and SCC. ► The expression of TCHHL1 proteins increased in epidermis of psoriasis vulgaris. - Abstract: Trichohyalin-like 1 (TCHHL1) protein is a novel member of the fused-type S100 protein gene family. The deduced amino acid sequence of TCHHL1 contains an EF-hand domain in the N-terminus, one trans-membrane domain and a nuclear localization signal. We generated specific antibodies against the C-terminus of the TCHHL1 protein and examined the expression of TCHHL1 proteins in normal and pathological human skin. An immunohistochemical study showed that TCHHL1 proteins were expressed in the basal layer of the normal epidermis. In addition, signals of TCHHL1 proteins were observed around the nuclei of cultured growing keratinocytes. Accordingly, TCHHL1 mRNA has been detected in normal skin and cultured growing keratinocytes. Furthermore, TCHHL1 proteins were strongly expressed in the peripheral areas of tumor nests in basal cell carcinomas and squamous cell carcinomas. A dramatic increase in the number of Ki67 positive cells was observed in TCHHL1-expressing areas. The expression of TCHHL1 proteins also increased in non-cancerous hyperproliferative epidermal tissues such as those of psoriasis vulgaris and lichen planus. These findings highlight the possibility that TCHHL1 proteins are expressed in growing keratinocytes of the epidermis and might be associated with the proliferation of keratinocytes.

  4. Expression and phosphorylation of neurofilament protein in different neuronal tissues

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The neurofilament proteins (NFPs) from different neuronal tissues including Alzheimer and Huntington disease gray matter, rat brain gray, white matter and spinal cord were separated biochemically into two major fractions. A systematic investigation on the distribution, expression and phosphorylation of NFPs in those fractions was undertaken in the present study. It was found that only non-phosphorylated NF-H and NF-M, but not NF-L subunit were detected in Alzheimer brain gray matter high speed supernatant, whereas all neurofilament subunits including non-phosphorylated and phosphorylated were measured in high speed pellet fraction of the same tissue. The hyperphosphorylation of NF-H and NF-M in Alzheimer brain was shown by phosphorylation dependent monoclonal antibodies SMI31 and SMI34. This hyperphosphorylation was confirmed by non-phosphorylation dependent antibody SMI32 with dephosphosphorylation of the samples. Furthermore, an increased amount of NF-H, NH-M and NF-L, detected by SMI33 and NR4 respectively, was also observed in Alzheimer samples, in which the elevation in NF-L was significant. A significantly different immunoblot patterns in distribution, expression and phosphorylation were determined in various position of the neural system and alternative fractions. To our best knowledge, this is the first data shown definite abnormality of NFPs in Alzheimer disease. The information obtained in the present study will be extremely valuable in further study of the proteins both in physiological and pathological conditions.

  5. Neurotoxocarosis alters myelin protein gene transcription and expression.

    Science.gov (United States)

    Heuer, Lea; Beyerbach, Martin; Lühder, Fred; Beineke, Andreas; Strube, Christina

    2015-06-01

    Neurotoxocarosis is an infection of the central nervous system caused by migrating larvae of the common dog and cat roundworms (Toxocara canis and Toxocara cati), which are zoonotic agents. As these parasites are prevalent worldwide and neuropathological and molecular investigations on neurotoxocarosis are scare, this study aims to characterise nerve fibre demyelination associated with neurotoxocarosis on a molecular level. Transcription of eight myelin-associated genes (Cnp, Mag, Mbp, Mog, Mrf-1, Nogo-A, Plp1, Olig2) was determined in the mouse model during six time points of the chronic phase of infection using qRT-PCR. Expression of selected proteins was analysed by Western blotting or immunohistochemistry. Additionally, demyelination and neuronal damage were investigated histologically. Significant differences (p ≤ 0.05) between transcription rates of T. canis-infected and uninfected control mice were detected for all analysed genes while T. cati affected five of eight investigated genes. Interestingly, 2', 3 ´-cyclic nucleotide 3'-phosphodiesterase (Cnp) and myelin oligodendrocyte glycoprotein (Mog) were upregulated in both T. canis- and T. cati-infected mice preceding demyelination. Later, CNPase expression was additionally enhanced. As expected, myelin basic protein (Mbp) was downregulated in cerebra and cerebella of T. canis-infected mice when severe demyelination was present 120 days post infectionem (dpi). The transcriptional pattern observed in the present study appears to reflect direct traumatic and hypoxic effects of larval migration as well as secondary processes including host immune reactions, demyelination and attempts to remyelinate damaged areas.

  6. Expression of p53 protein in pituitary adenomas

    Directory of Open Access Journals (Sweden)

    Oliveira M.C.

    2002-01-01

    Full Text Available Inactivating mutations of TP53, a tumor suppressor gene, are associated with abnormal cell proliferation. Although p53 expression is common in many human malignancies, p53 protein has seldom been evaluated in pituitary tumors. When detected, the percentage of p53-positive cells is low, and, in general, it is exclusive for invasive lesions. The aim of the present study was to use immunohistochemistry to determine the presence of p53 protein in pituitary adenomas from tumor samples of 163 surgeries performed in 148 patients (40% male, 60% female. In 35% of the cases the adenoma was nonfunctional, while in the others it was associated with PRL, GH and/or ACTH endocrine hypersecretion syndrome. Macroadenomas were observed in 83.2% of the cases with available neuroimage evaluation, of which 28% invaded the cavernous, sphenoid and/or ethmoidal sinus, bone, third ventricle or subfrontal lobe. p53 protein was detected in 2/148 patients (1.3%. Immunohistochemistry was positive for PRL and GH in these cases. Due to the high percentage of invasive pituitary adenomas found in our study, the low frequency of p53 detection suggests that it is inadequate as a routine marker for aggressiveness and as a predictive factor of tumor behavior.

  7. Expression pattern of protein kinase C δ during mouse embryogenesis

    Directory of Open Access Journals (Sweden)

    Carracedo Sergio

    2013-01-01

    Full Text Available Abstract Background The members of the protein kinase C (PKC family consist of serine/threonine kinases classified according to their regulatory domain. Those that belong to the novel PKC subfamily, such as PKCδ, are dependent on diacylglycerol but not Calcium when considering their catalytic activity. Although several studies have shown the importance of PKCδ in different cellular events in health and disease, the overall in vivo distribution of this PKC isoform during development is still lacking. Through Lac Z and antibody staining procedures, we show here the in vivo expression of PKCδ during mouse embryogenesis. Results Ganglia were the domains with most prominent expression of PKCδ in most of the stages analysed, although PKCδ could also be detected in heart and somites at earlier stages, and cartilage primordium and skin among other sites in older embryos. Conclusions The strong expression of PKCδ in ganglia during murine development shown in this study suggests a significant role of this isoform as well as redundancy with other PKCs within the nervous system, since PKCδ deficient mice develop normally.

  8. Real-time quantification of protein expression at the single-cell level via dynamic protein synthesis translocation reporters.

    Science.gov (United States)

    Aymoz, Delphine; Wosika, Victoria; Durandau, Eric; Pelet, Serge

    2016-04-21

    Protein expression is a dynamic process, which can be rapidly induced by extracellular signals. It is widely appreciated that single cells can display large variations in the level of gene induction. However, the variability in the dynamics of this process in individual cells is difficult to quantify using standard fluorescent protein (FP) expression assays, due to the slow maturation of their fluorophore. Here we have developed expression reporters that accurately measure both the levels and dynamics of protein synthesis in live single cells with a temporal resolution under a minute. Our system relies on the quantification of the translocation of a constitutively expressed FP into the nucleus. As a proof of concept, we used these reporters to measure the transient protein synthesis arising from two promoters responding to the yeast hyper osmolarity glycerol mitogen-activated protein kinase pathway (pSTL1 and pGPD1). They display distinct expression dynamics giving rise to strikingly different instantaneous expression noise.

  9. Pyruvate-fortified cardioplegia evokes myocardial erythropoietin signaling in swine undergoing cardiopulmonary bypass.

    Science.gov (United States)

    Ryou, Myoung-Gwi; Flaherty, Devin C; Hoxha, Besim; Sun, Jie; Gurji, Hunaid; Rodriguez, Steven; Bell, Glenn; Olivencia-Yurvati, Albert H; Mallet, Robert T

    2009-11-01

    Pyruvate-fortified cardioplegia protects myocardium and hastens postsurgical recovery of patients undergoing cardiopulmonary bypass (CPB). Pyruvate reportedly suppresses degradation of the alpha-subunit of hypoxia-inducible factor-1 (HIF-1), an activator of the gene encoding the cardioprotective cytokine erythropoietin (EPO). This study tested the hypothesis that pyruvate-enriched cardioplegia evoked EPO expression and mobilized EPO signaling mechanisms in myocardium. Hearts of pigs maintained on CPB were arrested for 60 min with 4:1 blood-crystalloid cardioplegia. The crystalloid component contained 188 mM glucose + or - 24 mM pyruvate. After 30-min cardiac reperfusion with cardioplegia-free blood, the pigs were weaned from CPB. Left ventricular myocardium was sampled 4 h after CPB for immunoblot assessment of HIF-1alpha, EPO and its receptor, the signaling kinases Akt and ERK, and endothelial nitric oxide synthase (eNOS), an effector of EPO signaling. Pyruvate-fortified cardioplegia stabilized arterial pressure post-CPB, induced myocardial EPO mRNA expression, and increased HIF-1alpha, EPO, and EPO-R protein contents by 60, 58, and 123%, respectively, vs. control cardioplegia (P Pyruvate cardioplegia also increased ERK phosphorylation by 61 and 118%, respectively, vs. control cardioplegia-treated and non-CPB sham myocardium (P pyruvate cardioplegia prevented these declines, yielding 49 and 80% greater NOS activity and eNOS content vs. respective control values (P Pyruvate-fortified cardioplegia induced myocardial EPO expression and mobilized the EPO-ERK-eNOS mechanism. By stabilizing HIF-1alpha, pyruvate-fortified cardioplegia may evoke sustained activation of EPO's cardioprotective signaling cascade in myocardium.

  10. Improved protein quality in transgenic soybean expressing a de novo synthetic protein, MB-16.

    Science.gov (United States)

    Zhang, Yunfang; Schernthaner, Johann; Labbé, Natalie; Hefford, Mary A; Zhao, Jiping; Simmonds, Daina H

    2014-06-01

    To improve soybean [Glycine max (L.) Merrill] seed nutritional quality, a synthetic gene, MB-16 was introduced into the soybean genome to boost seed methionine content. MB-16, an 11 kDa de novo protein enriched in the essential amino acids (EAAs) methionine, threonine, lysine and leucine, was originally developed for expression in rumen bacteria. For efficient seed expression, constructs were designed using the soybean codon bias, with and without the KDEL ER retention sequence, and β-conglycinin or cruciferin seed specific protein storage promoters. Homozygous lines, with single locus integrations, were identified for several transgenic events. Transgene transmission and MB-16 protein expression were confirmed to the T5 and T7 generations, respectively. Quantitative RT-PCR analysis of developing seed showed that the transcript peaked in growing seed, 5-6 mm long, remained at this peak level to the full-sized green seed and then was significantly reduced in maturing yellow seed. Transformed events carrying constructs with the rumen bacteria codon preference showed the same transcription pattern as those with the soybean codon preference, but the transcript levels were lower at each developmental stage. MB-16 protein levels, as determined by immunoblots, were highest in full-sized green seed but the protein virtually disappeared in mature seed. However, amino acid analysis of mature seed, in the best transgenic line, showed a significant increase of 16.2 and 65.9 % in methionine and cysteine, respectively, as compared to the parent. This indicates that MB-16 elevated the sulfur amino acids, improved the EAA seed profile and confirms that a de novo synthetic gene can enhance the nutritional quality of soybean.

  11. Evaluation of the influenza A replicon for transient expression of recombinant proteins in mammalian cells.

    Science.gov (United States)

    Krammer, Florian; Pontiller, Jens; Tauer, Christopher; Palmberger, Dieter; Maccani, Andreas; Baumann, Martina; Grabherr, Reingard

    2010-10-11

    Recombinant protein expression in mammalian cells has become a very important technique over the last twenty years. It is mainly used for production of complex proteins for biopharmaceutical applications. Transient recombinant protein expression is a possible strategy to produce high quality material for preclinical trials within days. Viral replicon based expression systems have been established over the years and are ideal for transient protein expression. In this study we describe the evaluation of an influenza A replicon for the expression of recombinant proteins. We investigated transfection and expression levels in HEK-293 cells with EGFP and firefly luciferase as reporter proteins. Furthermore, we studied the influence of different influenza non-coding regions and temperature optima for protein expression as well. Additionally, we exploited the viral replication machinery for the expression of an antiviral protein, the human monoclonal anti-HIV-gp41 antibody 3D6. Finally we could demonstrate that the expression of a single secreted protein, an antibody light chain, by the influenza replicon, resulted in fivefold higher expression levels compared to the usually used CMV promoter based expression. We emphasize that the influenza A replicon system is feasible for high level expression of complex proteins in mammalian cells.

  12. Cloning, expression and purification of recombinant streptokinase: partial characterization of the protein expressed in Escherichia coli

    Directory of Open Access Journals (Sweden)

    L. Avilán

    1997-12-01

    Full Text Available We cloned the streptokinase (STK gene of Streptococcus equisimilis in an expression vector of Escherichia coli to overexpress the profibrinolytic protein under the control of a tac promoter. Almost all the recombinant STK was exported to the periplasmic space and recovered after gentle lysozyme digestion of induced cells. The periplasmic fraction was chromatographed on DEAE Sepharose followed by chromatography on phenyl-agarose. Active proteins eluted between 4.5 and 0% ammonium sulfate, when a linear gradient was applied. Three major STK derivatives of 47.5 kDa, 45 kDa and 32 kDa were detected by Western blot analysis with a polyclonal antibody. The 32-kDa protein formed a complex with human plasminogen but did not exhibit Glu-plasminogen activator activity, as revealed by a zymographic assay, whereas the 45-kDa protein showed a Km = 0.70 µM and kcat = 0.82 s-1, when assayed with a chromogen-coupled substrate. These results suggest that these proteins are putative fragments of STK, possibly derived from partial degradation during the export pathway or the purification steps. The 47.5-kDa band corresponded to the native STK, as revealed by peptide sequencing

  13. Developmental expression of odorant-binding proteins and chemosensory proteins in the embryos of Locusta migratoria.

    Science.gov (United States)

    Yu, Yanxue; Zhang, Shangan; Zhang, Long; Zhao, Xingbo

    2009-06-01

    We have investigated the development of chemosensilla and the secretion of odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) in the embryo of Locusta migratoria manilensis. We first report the changes of each sensillum in embryo just preceding hatch in detail and show that different sensilla have different developmental processes. Trichogen cells are first involved in forming the structure of pegs, and then, after retraction, they start secreting OBPs and CSPs in the sensillar lymph. The synthesis of LmigOBP1 starts during the embryogenesis about 0.5 h preceding hatching, specifically in sensilla trichodea and basiconica of the antenna. LmigOBP2, instead, was only found in the outer sensillum lymph (oSl) of sensilla chaetica of the antenna, while we could not detect LmigOBP3 in any type of sensilla of the antenna. The ontogenesis of CSPs in the embryos is similar to that of OBPs. Expression of CSPI homolog in Locusta migratoria is detected using the antiserum raised against SgreCSPI. CSPI is specifically expressed in the outer sensillum lymph of sensilla chaetica of the antenna, and anti-LmigCSPII dose not label any sensilla of the embryos. These data indicate that in locusts, OBPs and CSPs follow different temporal expression patterns, and also that OBPs are expressed in different types of sensilla.

  14. SHuffle, a novel Escherichia coli protein expression strain capable of correctly folding disulfide bonded proteins in its cytoplasm

    Directory of Open Access Journals (Sweden)

    Lobstein Julie

    2012-05-01

    Full Text Available Abstract Background Production of correctly disulfide bonded proteins to high yields remains a challenge. Recombinant protein expression in Escherichia coli is the popular choice, especially within the research community. While there is an ever growing demand for new expression strains, few strains are dedicated to post-translational modifications, such as disulfide bond formation. Thus, new protein expression strains must be engineered and the parameters involved in producing disulfide bonded proteins must be understood. Results We have engineered a new E. coli protein expression strain named SHuffle, dedicated to producing correctly disulfide bonded active proteins to high yields within its cytoplasm. This strain is based on the trxB gor suppressor strain SMG96 where its cytoplasmic reductive pathways have been diminished, allowing for the formation of disulfide bonds in the cytoplasm. We have further engineered a major improvement by integrating into its chromosome a signal sequenceless disulfide bond isomerase, DsbC. We probed the redox state of DsbC in the oxidizing cytoplasm and evaluated its role in assisting the formation of correctly folded multi-disulfide bonded proteins. We optimized protein expression conditions, varying temperature, induction conditions, strain background and the co-expression of various helper proteins. We found that temperature has the biggest impact on improving yields and that the E. coli B strain background of this strain was superior to the K12 version. We also discovered that auto-expression of substrate target proteins using this strain resulted in higher yields of active pure protein. Finally, we found that co-expression of mutant thioredoxins and PDI homologs improved yields of various substrate proteins. Conclusions This work is the first extensive characterization of the trxB gor suppressor strain. The results presented should help researchers design the appropriate protein expression conditions using

  15. Differentially expressed protein markers in human submandibular and sublingual secretions.

    Science.gov (United States)

    Hu, Shen; Denny, Patricia; Denny, Paul; Xie, Yongming; Loo, Joseph A; Wolinsky, Lawrence E; Li, Yang; McBride, Jim; Ogorzalek Loo, Rachel R; Navazesh, Mavash; Wong, David T

    2004-11-01

    Proteome analysis of secretions from individual salivary glands is important for understanding the health of the oral cavity and pathogenesis of certain diseases. However, cross-contamination of submandibular (SM) and sublingual (SL) glandular secretions can occur. The close anatomic relationship of the SM and SL ductal orifices can lead to such contamination. Additionally, these glands may share common ducts. To insure the purity of SM/SL secretions for proteomic analysis, it is important to develop unique biomarkers which could be used to verify the integrity of the individual glandular saliva. In this study, a proteomics approach based on mass spectrometry and gel electrophoresis techniques was utilized to identify and verify a set of proteins (cystatin C, calgranulin B and MUC5B mucin), which are differentially expressed in SM/SL secretions. SM/SL fluids were obtained from nine healthy subjects. Cystatin C was found to be an SM-selective protein as it was found in all SM fluids but not detected in two SL fluids. MUC5B mucin and calgranulin B, on the other hand, were found to be SL-selective proteins. All SL samples contained MUC5B mucin, whereas MUC5B mucin was not detected in four SM samples. Eight of the SL samples contained calgranulin B; however, calgranulin B was absent in eight SM samples. This set of protein markers, especially calgranulin B, can be used to determine the purity of SM/SL samples, and therefore identify potential individuals who do not exhibit cross-contaminated SM/SL secretions, an important requirement for subsequent proteome analysis of pure SM and SL secretions.

  16. 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.

  17. Cardiac protein kinases: the cardiomyocyte kinome and differential kinase expression in human failing hearts

    OpenAIRE

    Fuller, Stephen J.; Osborne, Sally A.; Leonard, Sam J.; Hardyman, Michelle A.; Vaniotis, George; Allen, Bruce G.; Sugden, Peter H.; Clerk, Angela

    2015-01-01

    Aims. Protein kinases are potential therapeutic targets for heart failure, but most studies of cardiac protein kinases derive from other systems, an approach that fails to account for specific kinases expressed in the heart and the contractile cardiomyocytes. We aimed to define the cardiomyocyte kinome (i.e. the protein kinases expressed in cardiomyocytes) and identify kinases with altered expression in human failing hearts. Methods and Results. Expression profiling (Affymetrix microarrays) d...

  18. Expression of Trans-Membrane Proteins in vitro Using a Cell Free System

    Science.gov (United States)

    Weisse, Natalie; Noireaux, Vincent; Chalmeau, Jerome

    2010-10-01

    Trans-membrane proteins represent a significant portion of the proteins expressed by cells. The expression of proteins in vitro, however, remains a challenge. Numerous expression approaches have been developed with cell free expression (CFE) being one of the most promising. CFE is based on a transcription-translation system that has been extracted from E. coli bacteria. Adding the desired DNA allows expression of a selected protein, and in the presence of phospholipids the expression of trans-membrane proteins becomes possible. In order to express trans-membrane proteins in a closed native environment, the cell free system (CFS) is encapsulated with a phospholipid bilayer, creating an artificial cell. To verify protein expression, AquaporinZ (AqpZ), a well-known trans-membrane protein tagged with a green fluorescent protein (eGFP), was used so the expressed proteins could be seen under a fluorescent microscope. These artificial cells will serve as an experimental platform for testing the viability of the expressed trans-membrane proteins. Results from the manipulation of these artificial cells by attaching them to the slide surface through streptavidin-biotin bonding will be presented.

  19. Different protein expression of myocardium from Chinese mini-swine model of myocardial infarct

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yanfeng; YE Nengsheng; ZHANG Rongli; FENG Xue; LUO Guoan; WANG Yiming

    2007-01-01

    High-resolution two-dimensional gel electropho-resis (2-DE), followed by computer-assisted image analysis was used to screen protein patterns of normal and infarcted myocardial tissues for quantitative and qualitative differencesin protein expression. In the gels of pH 5-8 immobilizedpH gradient (IPG) strips, 851 protein spots were detected in normal myocardial tissue and 1 032 protein spots were resolved in infarcted myocardial tissue. Thirteen protein spots only expressed in normal myocardial tissue, and 14 protein spots only expressed in infarcted myocardial tissue. Results also showed that 49 protein spots displayed quantitative changes in expression between normal and infarcted myocar-dial tissue. Eleven protein spots were subjected to mass spectrometry (MS) analysis and seven proteins were identi-fied by peptide mass fingerprinting (PMF). These proteins may be involved in cardiovascular injury, and could play an important role in the treatment of coronary heart disease.

  20. Protein 53 expression in a mixed Labrador subcutaneous lymphoma

    Directory of Open Access Journals (Sweden)

    Annahita Rezaie

    2012-06-01

    Full Text Available An 11 year – old mixed female Labrador was presented with two masses in trunk and neck. The tumoral masses were excised and sent for histopathological and immunohistochemical analyses. Histopathological examination of masses revealed diffuse infiltration of small sized lymphoid cells in subcutaneous tissue which were intense around the blood vessels. More than 10% lymphoid cells were CD3 positive in the immunohistochemical staining and most of them were accumulated around vessels. Protein 53 (p53 expression was detected by brown nuclei in immunohistochemical staining. Subcutaneous lymphoma was diagnosed according to histopathological results. After 6 months the case was referred with multicentric lymphoma and based on the owner request euthanasia was performed. These findings emphasize on poor prognosis for tumors with p53 mutation.

  1. Acetazolamide inhibits aquaporin-1 protein expression and angiogenesis

    Institute of Scientific and Technical Information of China (English)

    Yang XIANG; Bing MA; Tao LI; Jun-wei GAO; He-ming YU; Xue-jun LI

    2004-01-01

    AIM: To study effects of acetazolamide on aquaporin-1 (AQP1) protein expression and angiogenesis. METHODS:Establishing Lewis-lung-carcinoma model, the localization of AQP1 in tumor tissues was investigated by immunohistochemical methods; The biological activity of acetazolamide was detected by endothelial cells proliferation test (MTT) assay and chorioallantoic membrane (CAM) vascular inhibition test. RESULTS: Immunohistochemical localization of AQP1 in mice tumor was labeled in capillaries, post capillary venules endothelial cells. After being treated with acetazolamide, the number of capillaries and post capillary venules was significantly decreased in tumor tissue. Acetazolamide showed significant inhibitory effect on angiogenesis in CAM and endothelial cell proliferation.CONCLUSION: Acetazolamide might be identified and developed as one of potential lead compounds for a new therapeutic intervention in inhibiting cancer angiogenesis.

  2. New examples of membrane protein expression and purification using the yeast based Pdr1-3 expression strategy.

    Science.gov (United States)

    Gupta, Rakeshkumar P; Kueppers, Petra; Schmitt, Lutz

    2014-12-10

    Overexpression and purification of membrane proteins has been a bottleneck for their functional and structural study for a long time. Both homologous and heterologous expression of membrane proteins with suitable tags for purification presents unique challenges for cloning and expression. Saccharomyces cerevisiae is a potential host system with significant closeness to higher eukaryotes and provides opportunity for attempts to express membrane proteins. In the past, bakers yeast containing mutations within the transcriptional regulator Pdr1 has been used to overexpress various membrane proteins including for example the ABC transporters Pdr5 and Yor1, respectively. In this study we exploited this system and tried to express and purify 3 membrane proteins in yeast along with Pdr5 and Yor1 viz. Rsb1, Mdl1 and Drs2 by virtue of an N-terminal 14-histidine affinity tag. Out of these five, we could express all membrane proteins although at different levels. Satisfactory yields were obtained for three examples i.e. Pdr5, Yor1 and Drs2. Rsb1 expression was comparatively low and Mdl1 was rather unsatisfactory. Thus, we demonstrate here the application of this yeast based expression system that is suitable for cloning, expression and purification of a wide variety of membrane proteins.

  3. Angiogenesis is induced by airway smooth muscle strain.

    Science.gov (United States)

    Hasaneen, Nadia A; Zucker, Stanley; Lin, Richard Z; Vaday, Gayle G; Panettieri, Reynold A; Foda, Hussein D

    2007-10-01

    Angiogenesis is an important feature of airway remodeling in both chronic asthma and chronic obstructive pulmonary disease (COPD). Airways in those conditions are exposed to excessive mechanical strain during periods of acute exacerbations. We recently reported that mechanical strain of human airway smooth muscle (HASM) led to an increase in their proliferation and migration. Sustained growth in airway smooth muscle in vivo requires an increase in the nutritional supply to these muscles, hence angiogenesis. In this study, we examined the hypothesis that cyclic mechanical strain of HASM produces factors promoting angiogenic events in the surrounding vascular endothelial cells. Our results show: 1) a significant increase in human lung microvascular endothelial cell (HMVEC-L) proliferation, migration, and tube formation following incubation in conditioned media (CM) from HASM cells exposed to mechanical strain; 2) mechanical strain of HASM cells induced VEGF expression and release; 3) VEGF neutralizing antibodies inhibited the proliferation, migration, and tube formations of HMVEC-L induced by the strained airway smooth muscle CM; 4) mechanical strain of HASM induced a significant increase in hypoxia-inducible factor-1alpha (HIF-1alpha) mRNA and protein, a transcription factor required for VEGF gene transcription; and 5) mechanical strain of HASM induced HIF-1alpha/VEGF through dual phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) and ERK pathways. In conclusion, exposing HASM cells to mechanical strain induces signal transduction pathway through PI3K/Akt/mTOR and ERK pathways that lead to an increase in HIF-1alpha, a transcription factor required for VEGF expression. VEGF release by mechanical strain of HASM may contribute to the angiogenesis seen with repeated exacerbation of asthma and COPD.

  4. Stable Surface Expression of a Gene for Helicobacter pylori Toxic Porin Protein with pBAD Expression System

    Institute of Scientific and Technical Information of China (English)

    Zhixiang PENG; Xi WEI; Zhengmei LIN

    2009-01-01

    successive passages could express Hope protein, while only 1 from 5 E. coli colonies that contained lac operon-regulated plasmid encoding hopE gene could express HopE. Indi-rect immunofluorescence confirmed the expression of HopE on E. coli cell surface.

  5. [Eukaryotic Expression and Immunogenic Research of Recombination Ebola Virus Membrane Protein Gp-Fc].

    Science.gov (United States)

    Zhang, Xiaoguang; Yang, Ren; Wang, Jiao; Wang, Xuan; Hou, Mieling; An, Lina; Zhu, Ying; Cao, Yuxi; Zeng, Yi

    2016-01-01

    We used 293 cells to express the recombinant membrane protein of the Ebola virus. Then, the immunogenicity of the recombinant protein was studied by immunized BALB/c mice. According to the codon use frequency of humans, the gene encoding the extracellular domain of the Ebola virus membrane protein was optimized, synthesized, and inserted into the eukaryotic expression plasmid pXG-Fc to construct the human IgG Fc and Ebola GP fusion protein expression plasmid pXG-modGP-Fc. To achieve expression, the fusion protein expression vector was transfected into high-density 293 cells using transient transfection technology. The recombinant protein was purified by protein A affinity chromatography. BALB/c mice were immunized with the purified fusion protein, and serum antibody titers evaluated by an indirect enzyme-linked immunosorbent assay (ELISA). Purification and analyses of the protein revealed that the eukaryotic expression vector could express the recombinant protein GP-Fc effectively, and that the recombinant protein in the supernatant of the cell culture was present as a dimer. After immunization with the purified recombinant protein, a high titer of antigen-specific IgG could be detected in the serum of immunized mice by indirect ELISA, showing that the recombinant protein had good immunogenicity. These data suggest that we obtained a recombinant protein with good immunogenicity. Our study is the basis for development of a vaccine against the Ebola virus and for screening of monoclonal antibodies.

  6. Connecting protein and mRNA burst distributions for stochastic models of gene expression

    CERN Document Server

    Elgart, Vlad; Fenley, Andrew T; Kulkarni, Rahul V

    2011-01-01

    The intrinsic stochasticity of gene expression can lead to large variability in protein levels for genetically identical cells. Such variability in protein levels can arise from infrequent synthesis of mRNAs which in turn give rise to bursts of protein expression. Protein expression occurring in bursts has indeed been observed experimentally and recent studies have also found evidence for transcriptional bursting, i.e. production of mRNAs in bursts. Given that there are distinct experimental techniques for quantifying the noise at different stages of gene expression, it is of interest to derive analytical results connecting experimental observations at different levels. In this work, we consider stochastic models of gene expression for which mRNA and protein production occurs in independent bursts. For such models, we derive analytical expressions connecting protein and mRNA burst distributions which show how the functional form of the mRNA burst distribution can be inferred from the protein burst distributio...

  7. Expression of interferon inducible protein-10 in pancreas of mice

    Institute of Scientific and Technical Information of China (English)

    Dong Li; Su-Wen Zhu; Dong-Juan Liu; Guo-Liang Liu

    2005-01-01

    AIM: To investigate the expression of interferon inducible protein-10 (IP-10) in pancreas of mice and to discuss its possible role in the pathogenesis of type 1 diabetes.METHODS: Non-obese diabetic (NOD) mice were used as experiment group and BALB/c mice as non-diabetic prone model. Immunohistochemistry method was used to evaluate the expression of IP-10 in the pancreas of NOD mice and BALB/c mice. Immunoelectron microscope was used to show the location of IP-10 in pancreatic islet β cells.RESULTS: Pancreatic islets were positively stained in all the NOD mice. Insulitis could be found in mice at the age of 4 wk. The weakly positive results were found in control group with no insulitis. Immunoelectron microscopy further demonstrated that IP-10 was produced by pancreatic β cells and stored in cytoplasm of the cells.CONCLUSION: IP-10 can be largely produced in pancreatic islets of NOD mice at the age of 2 wk when there is no significant insulitis, and may play an important part in the pathogenesis of type 1 diabetes by attracting immune cells to infiltrate the pancreatic islets.

  8. Expression of Yes-associated protein 1 gene and protein in oral squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    LI Song-ying; HU Ji-an; WANG Hui-ming

    2013-01-01

    Background Oral squamous cell carcinoma (OSCC) is one of the most common malignancies in the oral and maxillofaoial region.Yes-associated protein 1 (YAP1) has been implicated as a bona fide oncogene in solid tumors.We seek to elucidate the role of YAP1 in OSCC tissue.Methods We identified YAP1 gene and protein overexpression in 30 OSCC patients and 10 normal oral mucosa tissues by immunohistochemistry,Western blotting and reverse transcription polymerase chain reaction (RT-PCR).Results In the normal oral mucosa by immunohistochemical staining,YAP1 mainly located in both the cytoplasm and nucleus mainly the nuclei of the basal cells.In OSCC,the expression of YAP1 translocated from the nucleus to cytoplasm;YAP1 being mainly located in both the cytoplasm and nucleus of the adjacent mucosa.The expression of YAP1 gradual increased in normal oral mucosa,tumor adjacent mucosa and low grade,middle grade,high grade OSCC tissue by Western blotting.Significant difference was found between the expressions of the normal oral mucosa and OSCC tissue (P <0.05).The coincidence was detected between the normal oral mucosa and OSCC tissue by RT-PCR (P <0.05).Conclusions YAP1 is involved in the carcinogenesis and development of OSCC.There is a transformation between nucleus and cytoplasm.

  9. Expression and purification of recombinant proteins in Escherichia coli tagged with the metal-binding protein CusF.

    Science.gov (United States)

    Cantu-Bustos, J Enrique; Vargas-Cortez, Teresa; Morones-Ramirez, Jose Ruben; Balderas-Renteria, Isaias; Galbraith, David W; McEvoy, Megan M; Zarate, Xristo

    2016-05-01

    Production of recombinant proteins in Escherichia coli has been improved considerably through the use of fusion proteins, because they increase protein solubility and facilitate purification via affinity chromatography. In this article, we propose the use of CusF as a new fusion partner for expression and purification of recombinant proteins in E. coli. Using a cell-free protein expression system, based on the E. coli S30 extract, Green Fluorescent Protein (GFP) was expressed with a series of different N-terminal tags, immobilized on self-assembled protein microarrays, and its fluorescence quantified. GFP tagged with CusF showed the highest fluorescence intensity, and this was greater than the intensities from corresponding GFP constructs that contained MBP or GST tags. Analysis of protein production in vivo showed that CusF produces large amounts of soluble protein with low levels of inclusion bodies. Furthermore, fusion proteins can be exported to the cellular periplasm, if CusF contains the signal sequence. Taking advantage of its ability to bind copper ions, recombinant proteins can be purified with readily available IMAC resins charged with this metal ion, producing pure proteins after purification and tag removal. We therefore recommend the use of CusF as a viable alternative to MBP or GST as a fusion protein/affinity tag for the production of soluble recombinant proteins in E. coli.

  10. C-reactive protein inhibits survivin expression via Akt/mTOR pathway downregulation by PTEN expression in cardiac myocytes.

    Directory of Open Access Journals (Sweden)

    Beom Seob Lee

    Full Text Available C-reactive protein (CRP is one of the most important biomarkers for arteriosclerosis and cardiovascular disease. Recent studies have shown that CRP affects cell cycle and inflammatory process in cardiac myocytes. Survivin is also involved in cardiac myocytes replication and apoptosis. Reduction of survivin expression is associated with less favorable cardiac remodeling in animal models. However, the effect of CRP on survivin expression and its cellular mechanism has not yet been studied. We demonstrated that treatment of CRP resulted in a significant decrease of survivin protein expression in a concentration-dependent manner in cardiac myocytes. The upstream signaling proteins of survivin, such as Akt, mTOR and p70S6K, were also downregulated by CRP treatment. In addition, CRP increased the protein and mRNA levels of PTEN. The siRNA transfection or specific inhibitor treatment for PTEN restored the CRP-induced downregulation of Akt/mTOR/p70S6K pathway and survivin protein expression. Moreover, pretreatment with a specific p53 inhibitor decreased the CRP-induced PTEN expression. ERK-specific inhibitor also blocked the p53 phosphorylation and PTEN expression induced by CRP. Our study provides a novel insight into CRP-induced downregulation of survivin protein expression in cardiac myocytes through mechanisms that involved in downregulation of Akt/mTOR/p70S6K pathway by expression of PTEN.

  11. Differential dissolved protein expression throughout the life cycle of Giardia lamblia.

    Science.gov (United States)

    Lingdan, Li; Pengtao, Gong; Wenchao, Li; Jianhua, Li; Ju, Yang; Chengwu, Liu; He, Li; Guocai, Zhang; Wenzhi, Ren; Yujiang, Chen; Xichen, Zhang

    2012-12-01

    Giardia lamblia (G. lamblia) has a simple life cycle that alternates between a cyst and a trophozoite, and this parasite is an important human and animal pathogen. To increase our understanding of the molecular basis of the G. lamblia encystment, we have analyzed the soluble proteins expressed by trophozoites and cysts extracted from feces by quantitative proteomic analysis. A total of 63 proteins were identified by isobaric tags for relative and absolute quantitation (iTRAQ) labeling, and were categorized as cytoskeletal proteins, a cell-cycle-specific kinase, metabolic enzymes and stress resistance proteins. Importantly, we demonstrated that the expression of seven proteins differed significantly between trophozoites and cysts. In cysts, the expression of three proteins (one variable surface protein (VSP), ornithine carbamoyltransferase (OTC), β-tubulin) increased, whereas the expression of four proteins (14-3-3 protein, α-tubulin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), protein disulfide isomerase 2 (PDI-2)) decreased significantly when compared with the levels of these proteins in trophozoites. The mRNA expression patterns of four of these proteins (OTC, α-tubulin, GAPDH, VSP) were similar to the expression levels of the proteins. These seven proteins appear to play an important role in the completion of the life cycle of G. lamblia.

  12. Macrophage inflammatory protein-1 alpha expression in interstitial lung disease.

    Science.gov (United States)

    Standiford, T J; Rolfe, M W; Kunkel, S L; Lynch, J P; Burdick, M D; Gilbert, A R; Orringer, M B; Whyte, R I; Strieter, R M

    1993-09-01

    Mononuclear phagocyte (M phi) recruitment and activation is a hallmark of a number of chronic inflammatory diseases of the lung, including sarcoidosis and idiopathic pulmonary fibrosis (IPF). We hypothesized that macrophage inflammatory protein-1 (MIP-1 alpha), a peptide with leukocyte activating and chemotactic properties, may play an important role in mediating many of the cellular changes that occur in sarcoidosis and IPF. In initial experiments, we demonstrated that human rMIP-1 alpha exerted chemotactic activities toward both polymorphonuclear leukocytes and monocytes, and these activities were inhibited by treatment with rabbit anti-human MIP-1 alpha antiserum. In support of the potential role of MIP-1 alpha in interstitial lung disease, we detected MIP-1 alpha in the bronchoalveolar lavage fluid of 22/23 patients with sarcoidosis (mean 443 +/- 76 pg/ml) and 9/9 patients with IPF (mean 427 +/- 81 pg/ml), whereas detectable MIP-1 alpha was found in only 1/7 healthy subjects (mean 64 +/- 64 pg/ml). In addition, we found a 2.5- and 1.8-fold increase in monocyte chemotactic activity in BALF obtained from patients with sarcoidosis and IPF respectively, as compared to healthy subjects, and this monocyte chemotactic activity, but not neutrophil chemotactic activity, was reduced by approximately 22% when bronchoalveolar lavage fluid from sarcoidosis and IPF patients were preincubated with rabbit antihuman MIP-1 alpha antibodies. To determine the cellular source(s) of MIP-1 alpha within the lung, we performed immunohistochemical analysis of bronchoalveolar lavage cell pellets, transbronchial biopsies, and open lung biopsies obtained from patients with IPF and sarcoidosis. Substantial expression of cell-associated MIP-1 alpha was detected in M phi, including both alveolar AM phi and interstitial M phi. In addition, interstitial fibroblasts within biopsies obtained from sarcoid and IPF patients also expressed immunoreactive MIP-1 alpha. Minimal to no detectable MIP-1

  13. CLONING SEGMENT SPIKE PROTEIN GENE OF SARS-COV AND ITS EXPRESSION IN ESCHERICHIA COLI

    Institute of Scientific and Technical Information of China (English)

    刘中华; 许文波; 毛乃颖; 张燕; 朱贞; 崔爱利; 杨建国; 胡海涛

    2004-01-01

    Objective Expressing and purifying the segment of SARS-CoV spike protein in E.Coli. Methods The target gene was obtained by RT-PCR. The PCR product was cloned into pEGM- T Easy Vector, sequencing and double restriction digestion ( BamHⅠ,PstⅠ) were performed. The target gene was subcloned into PQE30 expression vector. The gene was expressed in the E.coli strain M15 cells induced by IPTG. The protein was purified with a nickel HiTrap chelating metal affinity column. Results The recombinant expression plasmid was successfully constructed and the protein was well expressed in E. coli strain M15 cells. The ideal pure protein was obtained by purification. Western blotting analysis suggested the protein could act with the convalescent sera of lab confirmed SARS patients. Conclusion The segment of SARS-CoV spike protein was well expressed and purified, and can be applied in diagnosis and immunological research of SARS.

  14. High expression level of soluble SARS spike protein mediated by adenovirus in HEK293 cells

    Institute of Scientific and Technical Information of China (English)

    Fei Zhong; Zhen-Yu Zhong; Shuang Liang; Xiu-Jin Li

    2006-01-01

    AIM: To develop a highly efficacious method for preparation of soluble SARS S-protein using adenovirus vector to meet the requirement for S-protein investigation.METHODS: The human adenovirus vector was used to express the soluble S-protein (corresponding to 1~1190 amino acids) fused with Myc/His tag using codon-optimized gene construct in HEK239 cells. The recombinant adenovirus bearing S-protein gene was generated by ligation method. The expressed S-protein with Myc/His tag was purified from culture medium with Ni-NTA agarose beads followed by dialysis. The S-protein was detected by Western blot and its biologic activity was analyzed by binding to Vero cells.RESULTS: Under the conditions of infection dose (MOI of 50) and expression time (48 h), the high-level expression of S-protein was obtained. The expression level was determined to be approximately 75 μg/106cells after purification. Purified soluble S-protein was readily detected by Western blot with anti-Myc antibody and showed the ability to bind to surface of Vero cells,demonstrating that the soluble S-protein could remain the biologic activity in the native molecule.CONCLUSION: The high-level expression of S-protein in HEK293 cells mediated by adenovirus can be achieved under the optimized expression conditions. The proteins possess the biologic activity, which lays a foundation for further investigation of S-protein biological function.

  15. Differentially expressed cytosolic proteins in human leukemia and lymphoma cell lines correlate with lineages and functions.

    Science.gov (United States)

    Gez, Swetlana; Crossett, Ben; Christopherson, Richard I

    2007-09-01

    Identification of cytosolic proteins differentially expressed between types of leukemia and lymphoma may provide a molecular basis for classification and understanding their cellular properties. Two-dimensional fluorescence difference gel electrophoresis (DIGE) and mass spectrometry have been used to identify proteins that are differentially expressed in cytosolic extracts from four human leukemia and lymphoma cell lines: HL-60 (acute promyelocytic leukemia), MEC1 (B-cell chronic lymphocytic leukemia), CCRF-CEM (T-cell acute lymphoblastic leukemia) and Raji (B-cell Burkitt's lymphoma). A total of 247 differentially expressed proteins were identified between the four cell lines. Analysis of the data by principal component analysis identified 22 protein spots (17 different protein species) differentially expressed at more than a 95% variance level between these cell lines. Several of these proteins were differentially expressed in only one cell line: HL-60 (myeloperoxidase, phosphoprotein 32 family member A, ras related protein Rab-11B, protein disulfide-isomerase, ran-specific GTPase-activating protein, nucleophosmin and S-100 calcium binding protein A4), and Raji (ezrin). Several of these proteins were differentially expressed in two cell lines: Raji and MEC1 (C-1-tetrahydrofolate synthase, elongation factor 2, alpha- and beta-tubulin, transgelin-2 and stathmin). MEC1 and CCRF-CEM (gamma-enolase), HL-60 and CCRF-CEM (ubiquitin-conjugating enzyme E2 N). The differentially expressed proteins identified in these four cell lines correlate with cellular properties and provide insights into the molecular basis of these malignancies.

  16. Induction of Ski protein expression upon luteinization in rat granulosa cells without a change in its mRNA expression.

    Science.gov (United States)

    Kim, Hyun; Yamanouchi, Keitaro; Matsuwaki, Takashi; Nishihara, Masugi

    2012-01-01

    The Ski protein is implicated in the proliferation/differentiation of a variety of cells. We previously reported that the Ski protein is present in granulosa cells of atretic follicles, but not in preovulatory follicles, suggesting that Ski has a role in apoptosis of granulosa cells. However, granulosa cells cannot only undergo apoptosis but can alternatively differentiate into luteal cells. It is unknown whether Ski is expressed and has a role in granulosa cells undergoing luteinization. Thus, the aim of the present study was to determine the localization of the Ski protein in the rat ovary during luteinization to examine if Ski might play a role in this process. In order to examine the Ski protein expression during the progression of luteinization, follicular growth was induced in immature female rats by administration of equine chorionic gonadotropin, and luteinization was induced by human chorionic gonadotropin treatment to mimic the luteinizing hormone (LH) surge. While no Ski-positive granulosa cells were present in the preovulatory follicle, Ski protein expression was induced in response to the LH surge and was maintained after formation of the corpus luteum (CL). Although the Ski protein is absent from the granulosa cells of the preovulatory follicle, its mRNA (c-ski) was expressed, and the level of c-ski mRNA was unchanged even after the LH surge. The combined results demonstrated that Ski protein expression is induced in granulosa cells upon luteinization, and suggested that its expression is regulated posttranscriptionally.

  17. The Arabidopsis thaliana MEDEA Polycomb group protein controls expression of PHERES1 by parental imprinting.

    Science.gov (United States)

    Köhler, Claudia; Page, Damian R; Gagliardini, Valeria; Grossniklaus, Ueli

    2005-01-01

    The maternally expressed Arabidopsis thaliana Polycomb group protein MEDEA (MEA) controls expression of the MADS-box gene PHERES1 (PHE1). Here, we show that PHE1 is mainly paternally expressed but maternally repressed and that this maternal repression of PHE1 breaks down in seeds lacking maternal MEA activity. Because Polycomb group proteins control parental imprinting in mammals as well, the independent recruitment of similar protein machineries for the imprinting of genes is a notable example of convergent evolution.

  18. How is mRNA expression predictive for protein expression? A correlation study on human circulating monocytes

    Institute of Scientific and Technical Information of China (English)

    Yanfang Guo; Yuan Chen; Hui Jiang; Lijun Tan; Jingyun Xie; Xuezhen Zhu; Songping Liang; Hongwen Deng; Peng Xiao; Shufeng Lei; Feiyan Deng; Gary Guishan Xiao; Yaozhong Liu; Xiangding Chen; Liming Li; Shan Wu

    2008-01-01

    A key assumption in studying mRNA expression is that it is informative in the prediction of protein expression. However,only limited studies have explored the mRNA-protein expression correlation in yeast or human tissues and the results have been relatively inconsistent. We carried out correlation analyses on mRNA-protein expressions in freshly isolated human circulating monocytes from 30 unrelated women. The expressed proteins for 71 genes were quantified and identified by 2-D electrophoresis coupled with mass spectrometry. The corresponding mRNA expressions were quantified by Affymetrix gene chips. Significant correlation (r=0.235, P<0.0001) was observed for the whole dataset including all studied genes and all samples. The correlations varied in different biological categories of gene ontology. For example, the highest correlation was achieved for genes of the extracellular region in terms of cellular component (r=0.643, P<0.0001) and the lowest correlation was obtained for genes of regulation (r=0.099, P=0.213) in terms of biological process. In the genome, half of the samples showed significant positive correlation for the 71 genes and significant correlation was found between the average mRNA and the average protein expression levels in all samples (r=0.296, P<0.01). However, at the study group level, only five studied genes had significant positive correlation across all the samples. Our results showed an overall positive correlation between mRNA and protein expression levels.However, the moderate and varied correlations suggest that mRNA expression might be sometimes useful, but certainly far from perfect, in predicting protein expression levels.

  19. An Approach to Heterologous Expression of Membrane Proteins. The Case of Bacteriorhodopsin.

    Science.gov (United States)

    Bratanov, Dmitry; Balandin, Taras; Round, Ekaterina; Shevchenko, Vitaly; Gushchin, Ivan; Polovinkin, Vitaly; Borshchevskiy, Valentin; Gordeliy, Valentin

    2015-01-01

    Heterologous overexpression of functional membrane proteins is a major bottleneck of structural biology. Bacteriorhodopsin from Halobium salinarum (bR) is a striking example of the difficulties in membrane protein overexpression. We suggest a general approach with a finite number of steps which allows one to localize the underlying problem of poor expression of a membrane protein using bR as an example. Our approach is based on constructing chimeric proteins comprising parts of a protein of interest and complementary parts of a homologous protein demonstrating advantageous expression. This complementary protein approach allowed us to increase bR expression by two orders of magnitude through the introduction of two silent mutations into bR coding DNA. For the first time the high quality crystals of bR expressed in E. Coli were obtained using the produced protein. The crystals obtained with in meso nanovolume crystallization diffracted to 1.67 Å.

  20. An Approach to Heterologous Expression of Membrane Proteins. The Case of Bacteriorhodopsin.

    Directory of Open Access Journals (Sweden)

    Dmitry Bratanov

    Full Text Available Heterologous overexpression of functional membrane proteins is a major bottleneck of structural biology. Bacteriorhodopsin from Halobium salinarum (bR is a striking example of the difficulties in membrane protein overexpression. We suggest a general approach with a finite number of steps which allows one to localize the underlying problem of poor expression of a membrane protein using bR as an example. Our approach is based on constructing chimeric proteins comprising parts of a protein of interest and complementary parts of a homologous protein demonstrating advantageous expression. This complementary protein approach allowed us to increase bR expression by two orders of magnitude through the introduction of two silent mutations into bR coding DNA. For the first time the high quality crystals of bR expressed in E. Coli were obtained using the produced protein. The crystals obtained with in meso nanovolume crystallization diffracted to 1.67 Å.

  1. Upregulation of hypoxia-inducible factors in normal and psoriatic skin.

    Science.gov (United States)

    Rosenberger, Christian; Solovan, Caius; Rosenberger, Alina D; Jinping, Li; Treudler, Regina; Frei, Ulrich; Eckardt, Kai-Uwe; Brown, Lawrence F

    2007-10-01

    Angiogenesis induced by vascular endothelial growth factor (VEGF) plays an important role in psoriasis. Hypoxic adaptation is conferred through hypoxia-inducible transcription factors (HIFs). VEGF and its receptor Flt-1 are HIF target genes. Growth factors and inflammatory cytokines activate the phosphoinositol-3 kinase pathway, and via activated protein kinase B (phospho-Akt) augment HIF activity. Here, we demonstrate that the major oxygen-dependent HIF isoforms are strongly upregulated in psoriatic skin: HIF-1alpha mainly in the epidermis, in an expression pattern similar to VEGF mRNA; HIF-2alpha in both the epidermis and in capillary endothelial cells of the dermis. In contrast, normal human skin shows low expression of HIF-alpha proteins, with the exception of hair follicles, and glands, which strongly express HIF-1alpha. In normal human skin, phospho-Akt appeared in the basal epidermal layer, in hair follicles, and in dermal glands. In contrast, in psoriasis, phospho-Akt expression was low in the epidermis, but markedly enhanced in the dermal capillaries and in surrounding interstitial/inflammatory cells. Our data suggest that hypoxia initiates a potentially self-perpetuating cycle involving HIF, VEGF, and Akt activation, which could drive physiologic growth of hair follicles and skin glands. Furthermore, such a cycle may exist in psoriasis in dermal capillaries and contribute to disease progression.

  2. Transformation of Drosophila cell lines: an alternative approach to exogenous protein expression.

    Science.gov (United States)

    Cherbas, Lucy; Cherbas, Peter

    2007-01-01

    Techniques and experimental applications are described for exogenous protein expression in Drosophila cell lines. Ways in which the Drosophila cell lines and the baculovirus expression vector system differ in their applications are emphasized.

  3. Glial fibrillary acidic protein isoform expression in plaque related astrogliosis in Alzheimer's disease

    NARCIS (Netherlands)

    Kamphuis, W.; Middeldorp, Jinte; Kooijman, Lieneke; Sluijs, Jacqueline A; Kooi, Evert-Jan; Moeton, Martina; Freriks, Michel; Mizee, Mark R; Hol, Elly M

    2014-01-01

    In Alzheimer's disease (AD), amyloid plaques are surrounded by reactive astrocytes with an increased expression of intermediate filaments including glial fibrillary acidic protein (GFAP). Different GFAP isoforms have been identified that are differentially expressed by specific subpopulations of ast

  4. Engineering Cowpea Mosaic Virus RNA-2 into a vector to express heterologous proteins in plants

    NARCIS (Netherlands)

    Kodetham Gopinath,; Wellink, J.; Porta, C.; Taylor, K.M.; Lomonossoff, G.P.; Kammen, van A.

    2000-01-01

    series of new cowpea mosaic virus (CPMV) RNA-2-based expression vectors were designed. The jellyfish green fluorescent protein (GFP) was introduced between the movement protein (MP) and the large (L) coat protein or downstream of the small (S) coat protein. Release of the GFP inserted between the MP

  5. RRE-dependent HIV-1 Env RNA effects on Gag protein expression, assembly and release

    Energy Technology Data Exchange (ETDEWEB)

    López, Claudia S., E-mail: lopezcl@ohsu.edu [Departments of Molecular Microbiology and Immunology, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239 (United States); Sloan, Rachel; Cylinder, Isabel [Departments of Molecular Microbiology and Immunology, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239 (United States); Kozak, Susan L.; Kabat, David [Biochemistry and Molecular Biology, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239 (United States); Barklis, Eric, E-mail: barklis@ohsu.edu [Departments of Molecular Microbiology and Immunology, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239 (United States)

    2014-08-15

    The HIV-1 Gag proteins are translated from the full-length HIV-1 viral RNA (vRNA), whereas the envelope (Env) protein is translated from incompletely spliced Env mRNAs. Nuclear export of vRNAs and Env mRNAs is mediated by the Rev accessory protein which binds to the rev-responsive element (RRE) present on these RNAs. Evidence has shown there is a direct or indirect interaction between the Gag protein, and the cytoplasmic tail (CT) of the Env protein. Our current work shows that env gene expression impacts HIV-1 Gag expression and function in two ways. At the protein level, full-length Env expression altered Gag protein expression, while Env CT-deletion proteins did not. At the RNA level, RRE-containing Env mRNA expression reduced Gag expression, processing, and virus particle release from cells. Our results support models in which Gag is influenced by the Env CT, and Env mRNAs compete with vRNAs for nuclear export. - Highlights: • At the protein level, full-length HIV-1 Env alters Gag protein expression. • HIV-1 Env RNA expression reduces Gag levels and virus release. • Env RNA effects on Gag are dependent on the RRE. • RRE-containing Env RNAs compete with vRNAs for nuclear export.

  6. Porcine bladder acellular matrix (ACM): protein expression, mechanical properties.

    Science.gov (United States)

    Farhat, Walid A; Chen, Jun; Haig, Jennifer; Antoon, Roula; Litman, Jessica; Sherman, Christopher; Derwin, Kathleen; Yeger, Herman

    2008-06-01

    Experimentally, porcine bladder acellular matrix (ACM) that mimics extracellular matrix has excellent potential as a bladder substitute. Herein we investigated the spatial localization and expression of different key cellular and extracellular proteins in the ACM; furthermore, we evaluated the inherent mechanical properties of the resultant ACM prior to implantation. Using a proprietary decellularization method, the DNA contents in both ACM and normal bladder were measured; in addition we used immunohistochemistry and western blots to quantify and localize the different cellular and extracellular components, and finally the mechanical testing was performed using a uniaxial mechanical testing machine. The mean DNA content in the ACM was significantly lower in the ACM compared to the bladder. Furthermore, the immunohistochemical and western blot analyses showed that collagen I and IV were preserved in the ACM, but possibly denatured collagen III in the ACM. Furthermore, elastin, laminin and fibronectin were mildly reduced in the ACM. Although the ACM did not exhibit nucleated cells, residual cellular components (actin, myosin, vimentin and others) were still present. There was, on the other hand, no significant difference in the mean stiffness between the ACM and the bladder. Although our decellularization method is effective in removing nuclear material from the bladder while maintaining its inherent mechanical properties, further work is mandatory to determine whether these residual DNA and cellular remnants would lead to any immune reaction, or if the mechanical properties of the ACM are preserved upon implantation and cellularization.

  7. Helicobacter pylori infection and expression of DNA mismatch repair proteins

    Institute of Scientific and Technical Information of China (English)

    Vahid Mirzaee; Mahsa Molaei; Hamid Mohaghegh Shalmani; Mohammad Reza Zali

    2008-01-01

    AIM:To determine the expression of DNA (MMR)proteins,including hMLH1 and hMSH2,in gastric epithelial cells in the patients with or without Hellcobacter pylori(H pylori)-infected gastritis.METHODS:Fifty H pylori-positive patients and 50 H pylori-negative patients were enrolled in the study.During endoscopy of patients with non-ulcer dyspepsia,two antral and two corpus biopsies were taken for histological examination (Giemsa stain)and for immunohistochemical staining of hMLH1 and hMSH2.RESULTS:The percentage of epithelial cell nuclei that demonstrated positivity for hMLH1 staining was 84.14±7.32% in Hpylori-negative patients,while it was 73.34±10.10% in Hpylori-positive patients (P <0.0001).No significant difference was seen between the two groups regarding the percentage of epithelial cell nuclei that demonstrated positivity for hMSH2 staining (81.16±8.32% in H pylori-negative versus 78.24±8.71% in Hpylori-positive patients,P=0.09).CONCLUSION:This study indicates that H pylori might promote development of gastric carcinoma at least in part through its ability to affect the DNA MMR system.

  8. Porcine bladder acellular matrix (ACM): protein expression, mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Farhat, Walid A [Department of Surgery, Division of Urology, University of Toronto and Hospital for Sick Children, Toronto, ON M5G 1X8 (Canada); Chen Jun; Haig, Jennifer; Antoon, Roula; Litman, Jessica; Yeger, Herman [Department of Developmental and Stem Cell Biology, Research Institute, Hospital for Sick Children, Toronto, ON M5G 1X8 (Canada); Sherman, Christopher [Department of Anatomic Pathology, Sunnybrook and Women' s College Health Sciences Centre, Toronto, ON (Canada); Derwin, Kathleen [Department of Biomedical Engineering, Lerner Research Institute and Orthopaedic Research Center, Cleveland Clinic Foundation, Cleveland, OH (United States)], E-mail: walid.farhat@sickkids.ca

    2008-06-01

    Experimentally, porcine bladder acellular matrix (ACM) that mimics extracellular matrix has excellent potential as a bladder substitute. Herein we investigated the spatial localization and expression of different key cellular and extracellular proteins in the ACM; furthermore, we evaluated the inherent mechanical properties of the resultant ACM prior to implantation. Using a proprietary decellularization method, the DNA contents in both ACM and normal bladder were measured; in addition we used immunohistochemistry and western blots to quantify and localize the different cellular and extracellular components, and finally the mechanical testing was performed using a uniaxial mechanical testing machine. The mean DNA content in the ACM was significantly lower in the ACM compared to the bladder. Furthermore, the immunohistochemical and western blot analyses showed that collagen I and IV were preserved in the ACM, but possibly denatured collagen III in the ACM. Furthermore, elastin, laminin and fibronectin were mildly reduced in the ACM. Although the ACM did not exhibit nucleated cells, residual cellular components (actin, myosin, vimentin and others) were still present. There was, on the other hand, no significant difference in the mean stiffness between the ACM and the bladder. Although our decellularization method is effective in removing nuclear material from the bladder while maintaining its inherent mechanical properties, further work is mandatory to determine whether these residual DNA and cellular remnants would lead to any immune reaction, or if the mechanical properties of the ACM are preserved upon implantation and cellularization.

  9. Construction of plant expression vector of Pseudopleuronectes americanus antifreeze protein gene

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Pseudopleuronectes americanus antifreeze protein gene was synthesized and control sequences were added such as 35S promoter and nos terminator that can facilitate the transcription and fi sequence and Kozak sequence that can improve the expression in translation level, the high expression cassette of antifreeze protein was constructed. This cassette was connected to pBI121.1 and finally got the high expression vector pBRTSAFP introduced into the maize callus. The expression of gus gene that linked to the antifreeze protein gene was detected, and the results was that the gus gene can express strongly and instantaneously.

  10. Protein kinase Cmu plays an essential role in hypertonicity-induced heat shock protein 70 expression.

    Science.gov (United States)

    Lim, Yun Sook; Lee, Jae Seon; Huang, Tai Qin; Seo, Jeong Sun

    2008-12-31

    Heat shock protein 70 (HSP70), which evidences important functions as a molecular chaperone and anti-apoptotic molecule, is substantially induced in cells exposed to a variety of stresses, including hypertonic stress, heavy metals, heat shock, and oxidative stress, and prevents cellular damage under these conditions. However, the molecular mechanism underlying the induction of HSP70 in response to hypertonicity has been characterized to a far lesser extent. In this study, we have investigated the cellular signaling pathway of HSP70 induction under hypertonic conditions. Initially, we applied a variety of kinase inhibitors to NIH3T3 cells that had been exposed to hypertonicity. The induction of HSP70 was suppressed specifically by treatment with protein kinase C (PKC) inhibitors (Gö6976 and GF109203X). As hypertonicity dramatically increased the phosphorylation of PKCmu, we then evaluated the role of PKCmu in hypertonicity-induced HSP70 expression and cell viability. The depletion of PKCmu with siRNA or the inhibition of PKCmu activity with inhibitors resulted in a reduction in HSP70 induction and cell viability. Tonicity-responsive enhancer binding protein (TonEBP), a transcription factor for hypertonicity-induced HSP70 expression, was translocated rapidly into the nucleus and was modified gradually in the nucleus under hypertonic conditions. When we administered treatment with PKC inhibitors, the mobility shift of TonEBP was affected in the nucleus. However, PKCmu evidenced no subcellular co-localization with TonEBP during hypertonic exposure. From our results, we have concluded that PKCmu performs a critical function in hypertonicity-induced HSP70 induction, and finally cellular protection, via the indirect regulation of TonEBP modification.

  11. Protein expression and preparation of polydonal antibody of AD-004 and study on its expression in the adrenal and testis

    Institute of Scientific and Technical Information of China (English)

    乔洁

    2006-01-01

    Objective To prepare rabbit antibody against mouse AD-004 by AD-004 expressed in the prokaryotic expression system and to identify its distribution in the testis and adrenal. Methods The full-length cDNA of mouse AD-004 was cloned into PET28 plasmid, and the protein was induced in E. coli BL21 bacteria by adding IPTG and then purified by Ni2+ -NTA column. The purified protein was used as an immunogene to prepare polyclonal

  12. Expression of RNA virus proteins by RNA polymerase II dependent expression plasmids is hindered at multiple steps

    Directory of Open Access Journals (Sweden)

    Überla Klaus

    2007-06-01

    Full Text Available Abstract Background Proteins of human and animal viruses are frequently expressed from RNA polymerase II dependent expression cassettes to study protein function and to develop gene-based vaccines. Initial attempts to express the G protein of vesicular stomatitis virus (VSV and the F protein of respiratory syncytial virus (RSV by eukaryotic promoters revealed restrictions at several steps of gene expression. Results Insertion of an intron flanked by exonic sequences 5'-terminal to the open reading frames (ORF of VSV-G and RSV-F led to detectable cytoplasmic mRNA levels of both genes. While the exonic sequences were sufficient to stabilise the VSV-G mRNA, cytoplasmic mRNA levels of RSV-F were dependent on the presence of a functional intron. Cytoplasmic VSV-G mRNA levels led to readily detectable levels of VSV-G protein, whereas RSV-F protein expression remained undetectable. However, RSV-F expression was observed after mutating two of four consensus sites for polyadenylation present in the RSV-F ORF. Expression levels could be further enhanced by codon optimisation. Conclusion Insufficient cytoplasmic mRNA levels and premature polyadenylation prevent expression of RSV-F by RNA polymerase II dependent expression plasmids. Since RSV replicates in the cytoplasm, the presence of premature polyadenylation sites and elements leading to nuclear instability should not interfere with RSV-F expression during virus replication. The molecular mechanisms responsible for the destabilisation of the RSV-F and VSV-G mRNAs and the different requirements for their rescue by insertion of an intron remain to be defined.

  13. Significance of Ebp1 and p53 protein expression in cervical cancer.

    Science.gov (United States)

    Liu, L; Li, X D; Chen, H Y; Cui, J S; Xu, D Y

    2015-10-02

    In this study, the ErbB3-binding protein (Ebp1) and p53 protein expression in cervical cancer tissues, and its significance in the prognosis of the disease was investigated. Ebp1 and p53 protein expression was detected by immunohistochemical analysis in cervical cancer tissues (N = 60) and normal tissues adjacent to the cancer tissues (N = 60). The rates of positive Ebp1 and p53 protein expression were 35.0 and 60.0%, respectively. Ebp1 and p53 were overexpressed in cervical cancer tissues, compared to normal tissues (P p53 protein expression was not correlated with age, tumor size, or family tumor history (P > 0.05). However, high levels of expression of Ebp1 and p53 were positively correlated with the TNM stage and lymphatic metastasis in cervical cancer patients (P p53 expression levels in cervical cancer patients could support the effective prediction of metastatic potential and patient prognosis.

  14. Prokaryotic expression and purification of fibronectin leucine rich transmembrane protein 3 C-terminal domain proteins in rats

    Institute of Scientific and Technical Information of China (English)

    Yan Cai; Jing Yang; He Huang; Fang Li; Ganqiu Wu; Jing Yang; Xuegang Luo

    2009-01-01

    BACKGROUND: Studies have suggested that fibronectin leucine-rich transmembrane protein 3 (FLRT3) is related to injury and regeneration of the nervous system. However, the expression and biological characteristics of these proteins remain poorly understood.OBJECTIVE: To obtain FLRT3 C-terminal gene fragments, to effectively express and purify the target proteins.DESIGN, TIME AND SETTING: An observational study of cellular and molecular biology was performed at the laboratory of Histology and Embryology in Xiangya School of Medicine, Central South University between October 2007 and June 2008.MATERIALS: Three Sprague Dawley adult rats were used to extract total RNA from rat brains. The pGEX4T3 and Escherichia coli (E. Coli) JM109 were purchased from Promega. E. Coil BL21 was provided by Novagen.METHODS: FLRT3 protein coding C-terminal DNA fragments, at a length of 786 bp, were amplified using RT-PCR technique from rat total RNA. The amplified products were cloned into the expression vector pGEX4T3. A recombinant expression vector was then constructed and introduced into E. Coli BL21. IsopropyI-D-thiogalactopyranoside was applied to induce expression of recombinant GST fusion proteins, followed by isolation, purification, and renaturation of inclusion bodies that comprised recombinant proteins. Finally, the purified recombinant protein was obtained.MAIN OUTCOME MEASURES: Determination of FLRT3 C-terminal DNA sequence; expression of target proteins was assayed by SDS-PAGE electrophoresis; purified recombinant protein was identified with Western blot methods.RESULTS: FLRT3 protein coding C-terminal DNA fragments, at a length of 786 bp, were successfully harvested through RT-PCR amplification, and were then cloned into the prokaryotic expression vector pGEX4T3. The results of the sequence were consistent with the known gene sequence. SDS-PAGE analysis demonstrated that there was a specific protein band in the recombinant GST fusion proteins at a relative molecular mass

  15. Downregulation of ATM Gene and Protein Expression in Canine Mammary Tumors

    DEFF Research Database (Denmark)

    Raposo-Ferreira, T M M; Bueno, R C; Terra, E M;

    2016-01-01

    tumors and nonmetastatic and metastatic mammary carcinomas (P > .05). The levels of ATM gene or protein expression were not significantly associated with clinical and pathological features or with survival. Similar to human breast cancer, the data in this study suggest that ATM gene and protein......The ataxia telangiectasia mutated (ATM) gene encodes a protein associated with DNA damage repair and maintenance of genomic integrity. In women, ATM transcript and protein downregulation have been reported in sporadic breast carcinomas, and the absence of ATM protein expression has been associated...... with poor prognosis. The aim of this study was to evaluate ATM gene and protein expression in canine mammary tumors and their association with clinical outcome. ATM gene and protein expression was evaluated by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry...

  16. Differential expression of proteins and phosphoproteins during larval metamorphosis of the polychaete Capitella sp. I

    Directory of Open Access Journals (Sweden)

    Qian Pei-Yuan

    2011-09-01

    Full Text Available Abstract Background The spontaneous metamorphosis of the polychaete Capitella sp. I larvae into juveniles requires minor morphological changes, including segment formation, body elongation, and loss of cilia. In this study, we investigated changes in the expression patterns of both proteins and phosphoproteins during the transition from larvae to juveniles in this species. We used two-dimensional gel electrophoresis (2-DE followed by multiplex fluorescent staining and MALDI-TOF mass spectrometry analysis to identify the differentially expressed proteins as well as the protein and phosphoprotein profiles of both competent larvae and juveniles. Results Twenty-three differentially expressed proteins were identified in the two developmental stages. Expression patterns of two of those proteins were examined at the protein level by Western blot analysis while seven were further studied at the mRNA level by real-time PCR. Results showed that proteins related to cell division, cell migration, energy storage and oxidative stress were plentifully expressed in the competent larvae; in contrast, proteins involved in oxidative metabolism and transcriptional regulation were abundantly expressed in the juveniles. Conclusion It is likely that these differentially expressed proteins are involved in regulating the larval metamorphosis process and can be used as protein markers for studying molecular mechanisms associated with larval metamorphosis in polychaetes.

  17. Differential expression of proteins and phosphoproteins during larval metamorphosis of the polychaete Capitella sp. I

    KAUST Repository

    Chandramouli, Kondethimmanahalli

    2011-09-03

    Background: The spontaneous metamorphosis of the polychaete Capitella sp. I larvae into juveniles requires minor morphological changes, including segment formation, body elongation, and loss of cilia. In this study, we investigated changes in the expression patterns of both proteins and phosphoproteins during the transition from larvae to juveniles in this species. We used two-dimensional gel electrophoresis (2-DE) followed by multiplex fluorescent staining and MALDI-TOF mass spectrometry analysis to identify the differentially expressed proteins as well as the protein and phosphoprotein profiles of both competent larvae and juveniles.Results: Twenty-three differentially expressed proteins were identified in the two developmental stages. Expression patterns of two of those proteins were examined at the protein level by Western blot analysis while seven were further studied at the mRNA level by real-time PCR. Results showed that proteins related to cell division, cell migration, energy storage and oxidative stress were plentifully expressed in the competent larvae; in contrast, proteins involved in oxidative metabolism and transcriptional regulation were abundantly expressed in the juveniles.Conclusion: It is likely that these differentially expressed proteins are involved in regulating the larval metamorphosis process and can be used as protein markers for studying molecular mechanisms associated with larval metamorphosis in polychaetes. © 2011 Chandramouli et al; licensee BioMed Central Ltd.

  18. Altered surfactant protein A gene expression and protein homeostasis in rats with emphysematous changes

    Institute of Scientific and Technical Information of China (English)

    HU Qiong-jie; XIONG Sheng-dao; ZHANG Hui-lan; SHI Xue-mei; XU Yong-jian; ZHANG Zhen-xiang; ZHEN Guo-hua; ZHAO Jian-ping

    2008-01-01

    Background The decrease of suffactant protein(SP)secreted by the alveolar type Ⅱ cell is one of the important causes of limiting air of pulmonary emphysema.However,the SP-A gene and protein changes in this disease are rarely studied.This study was undertaken to investigate alterations in SP-A gene activity and protein,and to explore their roles in the pathogenesis of emphysematous changes.Methods Twenty Wistar rats were divided randomly into a normal control group(n=10)and a cigarette smoking(CS)+lipopolysaccharide(LPS)group(n=10).Ultra-structural changes were obsewed under an electron microscope.The number of cells positive for SP-A was measured by immunohistochemistry.The mRNA expression and protein Ievel of SP-A in the lung tissues were determined by quantitative polymerase chain reaction(qPCR)and Western blot separately.The protein level of SP-A in lavage fluid was determined by Western blot.Results The number of cells positive for SP-A of the CS+LPS group(0.35±0.03)was lower than that of the blank control group(0.72±0.06,P<0.05).The level of SP-A in the lung tissues of rats in the CS+LPS group(0.2765±0.0890)was lower than that in the blank controI group(0.6875±0.1578,P<0.05).The level of SP-A in the lavage fluid of rats in the CS+LPS group(0.8567±0.1458)was lower than that in the blank controI group(1.3541±0.2475,P<0.05).The lung tissues of rats in the CS+LPS group showed an approximate increase(0.4-fold)in SP-A mRNA levels relative to β-actin mRNA (P<0.05).Conclusions The changes of SP-A may be related to emphysematous changes in the lung.And cigarette smoke and LPS alter lung SP-A gene activity and protein homeostasis.

  19. Variation in cell signaling protein expression may introduce sampling bias in primary epithelial ovarian cancer.

    Science.gov (United States)

    Mittermeyer, Gabriele; Malinowsky, Katharina; Beese, Christian; Höfler, Heinz; Schmalfeldt, Barbara; Becker, Karl-Friedrich; Avril, Stefanie

    2013-01-01

    Although the expression of cell signaling proteins is used as prognostic and predictive biomarker, variability of protein levels within tumors is not well studied. We assessed intratumoral heterogeneity of protein expression within primary ovarian cancer. Full-length proteins were extracted from 88 formalin-fixed and paraffin-embedded tissue samples of 13 primary high-grade serous ovarian carcinomas with 5-9 samples each. In addition, 14 samples of normal fallopian tube epithelium served as reference. Quantitative reverse phase protein arrays were used to analyze the expression of 36 cell signaling proteins including HER2, EGFR, PI3K/Akt, and angiogenic pathways as well as 15 activated (phosphorylated) proteins. We found considerable intratumoral heterogeneity in the expression of proteins with a mean coefficient of variation of 25% (range 17-53%). The extent of intratumoral heterogeneity differed between proteins (p<0.005). Interestingly, there were no significant differences in the extent of heterogeneity between phosphorylated and non-phosphorylated proteins. In comparison, we assessed the variation of protein levels amongst tumors from different patients, which revealed a similar mean coefficient of variation of 21% (range 12-48%). Based on hierarchical clustering, samples from the same patient clustered more closely together compared to samples from different patients. However, a clear separation of tumor versus normal tissue by clustering was only achieved when mean expression values of all individual samples per tumor were analyzed. While differential expression of some proteins was detected independently of the sampling method used, the majority of proteins only demonstrated differential expression when mean expression values of multiple samples per tumor were analyzed. Our data indicate that assessment of established and novel cell signaling proteins as diagnostic or prognostic markers may require sampling of serous ovarian cancers at several distinct

  20. Variation in cell signaling protein expression may introduce sampling bias in primary epithelial ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Gabriele Mittermeyer

    Full Text Available Although the expression of cell signaling proteins is used as prognostic and predictive biomarker, variability of protein levels within tumors is not well studied. We assessed intratumoral heterogeneity of protein expression within primary ovarian cancer. Full-length proteins were extracted from 88 formalin-fixed and paraffin-embedded tissue samples of 13 primary high-grade serous ovarian carcinomas with 5-9 samples each. In addition, 14 samples of normal fallopian tube epithelium served as reference. Quantitative reverse phase protein arrays were used to analyze the expression of 36 cell signaling proteins including HER2, EGFR, PI3K/Akt, and angiogenic pathways as well as 15 activated (phosphorylated proteins. We found considerable intratumoral heterogeneity in the expression of proteins with a mean coefficient of variation of 25% (range 17-53%. The extent of intratumoral heterogeneity differed between proteins (p<0.005. Interestingly, there were no significant differences in the extent of heterogeneity between phosphorylated and non-phosphorylated proteins. In comparison, we assessed the variation of protein levels amongst tumors from different patients, which revealed a similar mean coefficient of variation of 21% (range 12-48%. Based on hierarchical clustering, samples from the same patient clustered more closely together compared to samples from different patients. However, a clear separation of tumor versus normal tissue by clustering was only achieved when mean expression values of all individual samples per tumor were analyzed. While differential expression of some proteins was detected independently of the sampling method used, the majority of proteins only demonstrated differential expression when mean expression values of multiple samples per tumor were analyzed. Our data indicate that assessment of established and novel cell signaling proteins as diagnostic or prognostic markers may require sampling of serous ovarian cancers at

  1. Expression and Significance of WT1 and Betacatenin Proteins in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Feng Zhou

    2013-12-01

    Full Text Available Objective: To investigate the expression, clinic-pathologic significance and the relevance of WT1 protein β-catenin protein in non-small cell lung cancer (NSCLC. Methods: A total of 48 paraffin-embedded tissue samples from patients with resected NSCLC were collected and none had received radiotherapy or chemotherapy before surgical resection. The expressions of WT1 and β-catenin proteins were detected with immunohistchemistry. All data were dealt with SPSS19.0 statistical software while the relationship between WT1 protein or β-catenin protein and each clinical pathological characteristic was tested by Pearson X2 and Fisher’s Exact Test, and X2 test of independence of two attributes was performed for the relevant analysis of the two indexes. Results: The positive expression rates of WT1 and aberrant β-catenin proteins were 62.5% (30/48 and 72.9% (35/48 in NSCLC, respectively. There was significant association between WT1 protein and lymph node metastasis (X2 = 4.480, df = 1, P = 0.034, but no obvious connection was observed between WT1 protein and genders, ages, tumor sizes, pathological patterns, differentiated degrees and pTNM stagings (P > 0.05. Aberrant expression of β-catenin protein was closely correlated with differentiation degrees (X2 = 8.224, df = 2, P = 0.016, and the results of further comparisons of differentiation degrees showed that there were significant differences between highly and moderately differentiated groups (P = 0.026, and between highly and lowly differentiated groups (P = 0.031, but the difference between moderately and lowly differentiated groups was not significant (P = 0.655. Similar to WT1 protein, there was no close relation between the aberrant expression of β-catenin protein and genders, ages, tumor sizes, pathological patterns, differentiated degrees and pTNM stagings (P > 0.05. The relationship between WT1 protein expression and aberrant expression of β-catenin protein was analyzed

  2. [Cloning and prokaryotic expression of transcriptional co-activator gene of Clonorchis sinensis and functional analysis of the expressed protein].

    Science.gov (United States)

    Zhang, Yong-li; Yu, Xin-bing; Wu, De; Wu, Zhong-dao; Bi, Hui-xiang

    2005-02-28

    To construct prokaryotic recombinant plasmids of transcriptional co-activator (TC) gene of Clonorchis sinensis, express and purify the recombinant protein and analyze its biological function. A pair of primers was designed according to the known sequence of TC gene. The TC gene fragment was amplified by PCR. After purification and digestion with BamH I and Sal I, the TC gene was connected to the prokaryotic expression vectors, pGEX-4T-1 and pET30a(+). By cloning target gene into these vectors, pGEX-4T-1 and pET30a(+), prokaryotic recombinant plasmids of TC gene were constructed and transferred into E. coli BL21. The positive expressed recombinants were detected by SDS-PAGE and Western blotting. Immobilized metal (Ni2+) chelation affinity chromatography was used to purify His-TC produced by the expression of the recombinant protein pET30a(+)-TC. The recombinant plasmids, pGEX-4T-1-TC and pET30a(+)-TC, were constructed successfully. SDS-PAGE testified that the molecular weight of the recombinant protein was correct. Western blot analysis of GST-TC recombinant protein testified that the recombinant protein could be recognized by immunized rabbit serum, which means the protein is GST-immune active and the clone can express recombinant Clonorchis sinensis antigen. After affinity chromatography of the pET-TC protein, there was only one protein band with expected size on the SDS-PAGE gel. The TC gene was screened from cDNA library of adult Clonorchis sinensis, cloned, expressed and purified. The purified protein of TC gene will be of importance for further research on the biological function of the gene.

  3. CONSTRUCTION, EXPRESSION AND BIOLOGICAL ASSESSMENT OF BPI23-Fcγ 1 RECOMBINANT PROTEIN PROKARYOTIC EXPRESSION VECTOR

    Institute of Scientific and Technical Information of China (English)

    安云庆; 管远志; 柯岩; 杨贵贞

    2002-01-01

    Objective. To construct pBV-BPI600-Fcγ 1700 recombinant expression vector, to transform it into Escherichia coli DH5α , and to induce the expression of BPI23-Fcγ 1 anti-bacterial recombinant protein. Methods. Genes coding for BPI23 and Fcγ 1 were amplified by RT-PCR from mRNA extracted from HL-60 cell and normal human leukocytes; recombinant cloning vector and recombinant expression vector were then constructed. pBV-BPI600-Fcγ 1700 recombinant expression vector was transformed into the competent Escherichia coli DH5α and BPI23-Fcγ 1 recombinant protein was expressed by a temperature-induced method. Results. (1) Expected amplified products BPI600bp and Fcγ 1700bp were obtained by RT-PCR method. (2) pUC18-BPI180, pUC18-BPI420 and pUC18-Fcγ 1700 recombinant cloning vectors were successfully constructed, and sequences were identical with the reported ones. (3) pBV-BPI600-Fcγ 1700 recombinant expression vector was successfully constructed, and the enzyme digestion analysis showed an expected result. (4) The expression level of BPI23-Fcγ 1 recombinant protein accounted for 20% of total bacterial proteins. (5) The renatured BPI23-Fcγ 1 recombinant protein showed bacteriocidal activity and biological function of complement fixation, and opsonization. Conclusion. pBV-BPI600-Fcγ 1700 recombinant expression vector was successfully constructed, and BPI23-Fcγ 1 recombinant protein with double biological activity of BPI and IgGFc was expressed in Escherichia coli.

  4. CONSTRUCTION,EXPRESSION AND BIOLOGICAL ASSESSMENT OF BPI23—Fcγ1 RECOMBINANT PROTEIN PROKARYOTIC EXPRESSION VECTOR

    Institute of Scientific and Technical Information of China (English)

    安云庆; 管远志; 等

    2002-01-01

    Objective:To construct pBV-BPI600-Fcγ1700 recombinant expression vector,to transform it into Escherichia coli DH5α,and to induce the expression of BPI23-Fcγ1 anti-bacterial recombinant protein.Methods:Genes coding for BPI23 and Fcγ1 were amplified by RT-PCR from mRNA extracted from Hl-60 cell and normal human leukocytes;recombinant cloning vector and recombinant expression vector were then constructed.pBV-BPI600-Fcγ1700 recombinant expression vector was transformed into the competent Escherichia coli DH5α and BPI23-Fcγ1 recombinant protein was expressed by a temperature-induced method.Results:(1)Expected amplified products BPI600bp and Fcγ1700bp were obtained by RT-PCR method.(2)pUC18-BPI180,pUC18-BPI420 and pUC18-Fcγ1700 recombinant cloning vectors were successfully constructed, and sequences were identical with the reported ones.(3)pBV-BPI600-Fcγ1700 recombinant expression vector was successfully constructed,and the enzyme digestion analysis showed an expected result.(4)The expression level of BPI23-Fcγ1 recombinant protein accounted for 20% of total bacterial proteins.(5)The renatured BPI23-Fcγ1 recombinant protein showed bacteriocidal activity and biological function of complement fixation,and opsonization.Conclusion:pBV-BPI600-Fcγ1700 recombinant expression vector was successfully constructed,and BPI23-Fcγ1 recombinant protein with double biological activity of BPI and IgGFc was expressed in Escherichia coli.

  5. Predicting protein-protein interactions in Arabidopsis thaliana through integration of orthology, gene ontology and co-expression

    Directory of Open Access Journals (Sweden)

    Vandepoele Klaas

    2009-06-01

    Full Text Available Abstract Background Large-scale identification of the interrelationships between different components of the cell, such as the interactions between proteins, has recently gained great interest. However, unraveling large-scale protein-protein interaction maps is laborious and expensive. Moreover, assessing the reliability of the interactions can be cumbersome. Results In this study, we have developed a computational method that exploits the existing knowledge on protein-protein interactions in diverse species through orthologous relations on the one hand, and functional association data on the other hand to predict and filter protein-protein interactions in Arabidopsis thaliana. A highly reliable set of protein-protein interactions is predicted through this integrative approach making use of existing protein-protein interaction data from yeast, human, C. elegans and D. melanogaster. Localization, biological process, and co-expression data are used as powerful indicators for protein-protein interactions. The functional repertoire of the identified interactome reveals interactions between proteins functioning in well-conserved as well as plant-specific biological processes. We observe that although common mechanisms (e.g. actin polymerization and components (e.g. ARPs, actin-related proteins exist between different lineages, they are active in specific processes such as growth, cancer metastasis and trichome development in yeast, human and Arabidopsis, respectively. Conclusion We conclude that the integration of orthology with functional association data is adequate to predict protein-protein interactions. Through this approach, a high number of novel protein-protein interactions with diverse biological roles is discovered. Overall, we have predicted a reliable set of protein-protein interactions suitable for further computational as well as experimental analyses.

  6. Gene expression, autonomic function and chronic hypoxia:lessons from the Andes.

    Science.gov (United States)

    Appenzeller, Otto; Minko, Tamara; Qualls, Clifford; Pozharov, Vitaly; Gamboa, Jorge; Gamboa, Alfredo; Wang, Yang

    2006-06-01

    Autonomic function is altered by altitude in sojourners and natives. We hypothesized that these physiologic responses are modulated by changes in gene expression. We compared gene product levels in 20 natives of Cerro de Pasco (CP), (4338 m), 10 of which had chronic mountain sickness (CMS) established by a CMS-scoring system, with gene products in the same men after 1 h at sea level. We further compared the results with those obtained from 10 US men residing at 1500 m. We measured gene products in white cells by reverse transcription polymerase chain reaction (RT-PCR). We focused on genes important in vascular autonomic physiology, and/or activated by hypoxia; hypoxia inducible factor 1-alpha (HIF 1-alpha), 2 splicing variants of vascular endothelial growth factor (VEGF); VEGF-121, VEGF-165, and phosphoglycerate kinase 1 (PGK 1). Normal CP natives showed high expression of all genes in CP, compared to US controls. Within 1 h of arrival at sea level, they had comparable levels to US residents. In CMS, the gene products were higher in CP. Although gene products decreased in Lima in this group, they never reached US values. VEGF 121 and 165 were correlated (P<0.001). VEGF 165 was higher in CMS in CP (P=0.006), and was positively correlated with CMS-score (R=0.86, P<0.001), and negatively correlated with arterial saturation (R=-0.79, P<0.001). Our findings underscore the changes in gene expression levels in intact humans in response to environmental stress. These changes may support the physiologic alterations induced by the ambient hypoxia at altitude and impact organism survival. They also suggest therapeutic strategies for autonomic and neurodegenerative diseases at sea level.

  7. Schisandrin B protects PC12 cells by decreasing the expression of amyloid precursor protein and vacuolar protein sorting 35

    Institute of Scientific and Technical Information of China (English)

    Mingmin Yan; Shanping Mao; Huimin Dong; Baohui Liu; Qian Zhang; Gaofeng Pan; Zhiping Fu

    2012-01-01

    PC12 cell injury was induced using 20 μM amyloid β-protein 25-35 to establish a model of Alzheimer's disease.The cells were then treated with 5, 10, and 25 μM Schisandrin B.Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25-35 gradually increased and the rate of apoptosis gradually decreased.Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased.Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change.These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25-35 in a dose-dependent manner.This may be caused by decreasing the expression of vacuolar protein sorting 35 and amyloid precursor protein.PC12 cell injury was induced using 20 μM amyloid β-protein 25-35 to establish a model of Alzheimer's disease.The cells were then treated with 5, 10, and 25 μM Schisandrin B.Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25-35 gradually increased and the rate of apoptosis gradually decreased.Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased.Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change.These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25

  8. Teaching Molecular Biology to Undergraduate Biology Students: An Illustration of Protein Expression and Purification

    Science.gov (United States)

    Sommer, Cesar Adolfo; Silva, Flavio Henrique; Novo, Maria Teresa Marques

    2004-01-01

    Practical classes on protein expression and purification were given to undergraduate biology students enrolled in the elective course "Introduction to Genetic Engineering." The heterologous expression of the green fluorescent protein (GFP)* of "Aequorea victoria" is an interesting system for didactic purposes because it can be viewed easily during…

  9. Evolved Lactococcus lactis Strains for Enhanced Expression of Recombinant Membrane Proteins

    NARCIS (Netherlands)

    Martinez Linares, Daniel; Geertsma, Eric R.; Poolman, Bert

    2010-01-01

    The production of complex multidomain (membrane) proteins is a major hurdle in structural genomics and a generic approach for optimizing membrane protein expression is still lacking. We have devised a selection method to isolate mutant strains with improved functional expression of recombinant membr

  10. Transient expression of a mitochondrial precursor protein - A new approach to study mitochondrial protein import in cells of higher eukaryotes

    NARCIS (Netherlands)

    Huckriede, A; Heikema, A; Wilschut, J; Agsteribbe, E

    1996-01-01

    In order to study mitochondrial protein import in the context of whole cell metabolism, we have used the transfection technique based on Semliki Forest virus (SFV) to express a mitochondrial precursor protein within BHK21 cells and human fibroblasts. Recombinant SFV particles mediate a highly effici

  11. [Expression of MCL-1 and BAK proteins in nutritional anemia and its clinical significance].

    Science.gov (United States)

    Guo, Yu-Jie; Wang, Yan; Lin, Feng-Ru

    2012-12-01

    This study was aimed to investigate the relation of MCL-1 and BAK proteins with incidence and development of nutritional anemia (NA) and their clinical significance. The MCL-1 and BAK protein levels in serum of 66 patients with NA were determined by using ELISA. Eighteen healthy people were randomly selected as normal controls. The results indicated that: (1) as compared with normal control group, the expression level of MCL-1 protein in 3 NA groups (iron-deficiency anemia, macrocytic anemia, mixed anemia) significantly decreased (P < 0.001), while the expression level of BAK protein obviously increased (P < 0.001), but the expression level of MCL-1 and BAK proteins among 3 NA groups showed no obvious differences; (2) the MCL-1 protein expression level increased and BAK protein expression level decreased in 3 NA groups after treatment (P < 0.05). (3) there was negative correlation of expression levels of MCL-1 protein with BAK protein in NA group (r = -0.858 P < 0.05). It is concluded that the MCL-1 and BAK proteins may play an important role in the incidence and development of NA, and can be used as the assist index for defining diagnosis and evaluate prognosis of NA.

  12. Stress protein expression in early phase spinal cord ischemia/reperfusion injury*

    Institute of Scientific and Technical Information of China (English)

    Shanyong Zhang; Dankai Wu; Jincheng Wang; Yongming Wang; Guoxiang Wang; Maoguang Yang; Xiaoyu Yang

    2013-01-01

    Spinal cord ischemia/reperfusion injury is a stress injury to the spinal cord. Our previous studies using differential proteomics identified 21 differential y expressed proteins (n > 2) in rabbits with spinal cord ischemia/reperfusion injury. Of these proteins, stress-related proteins included protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70. In this study, we established New Zealand rabbit models of spinal cord ischemia/reperfusion injury by abdominal aorta occlusion. Results demonstrated that hind limb function initial y improved after spinal cord ischemia/reperfusion injury, but then deteriorated. The pathological morphology of the spinal cord became aggravated, but lessened 24 hours after reperfusion. However, the numbers of motor neurons and interneurons in the spinal cord gradual y decreased. The expression of protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70 was induced by ischemia/reperfusion injury. The expression of these proteins increased within 12 hours after reperfusion, and then decreased, reached a minimum at 24 hours, but subsequently increased again to similar levels seen at 6–12 hours, showing a characterization of induction-inhibition-induc-tion. These three proteins were expressed only in cytoplasm but not in the nuclei. Moreover, the expression was higher in interneurons than in motor neurons, and the survival rate of interneurons was greater than that of motor neurons. It is assumed that the expression of stress-related proteins exhibited a protective effect on neurons.

  13. Enhanced protein expression in the baculovirus/insect cell system using engineered SUMO fusions.

    Science.gov (United States)

    Liu, Li; Spurrier, Joshua; Butt, Tauseef R; Strickler, James E

    2008-11-01

    Recombinant protein expression in insect cells varies greatly from protein to protein. A fusion tag that is not only a tool for detection and purification, but also enhances expression and/or solubility would greatly facilitate both structure/function studies and therapeutic protein production. We have shown that fusion of SUMO (small ubiquitin-related modifier) to several test proteins leads to enhanced expression levels in Escherichia coli. In eukaryotic expression systems, however, the SUMO tag could be cleaved by endogenous desumoylase. In order to adapt SUMO-fusion technology to these systems, we have developed an alternative SUMO-derived tag, designated SUMOstar, which is not processed by native SUMO proteases. In the present study, we tested the SUMOstar tag in a baculovirus/insect cell system with several proteins, i.e. mouse UBP43, human tryptase beta II, USP4, USP15, and GFP. Our results demonstrate that fusion to SUMOstar enhanced protein expression levels at least 4-fold compared to either the native or His(6)-tagged proteins. We isolated active SUMOstar tagged UBP43, USP4, USP15, and GFP. Tryptase was active following cleavage with a SUMOstar specific protease. The SUMOstar system will make significant impact in difficult-to-express proteins and especially to those proteins that require the native N-terminal residue for function.

  14. Analysis of differential protein expression in normal and neoplastic human breast epithelial cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Williams, K.; Chubb, C.; Huberman, E.; Giometti, C.S.

    1997-07-01

    High resolution two dimensional get electrophoresis (2DE) and database analysis was used to establish protein expression patterns for cultured normal human mammary epithelial cells and thirteen breast cancer cell lines. The Human Breast Epithelial Cell database contains the 2DE protein patterns, including relative protein abundances, for each cell line, plus a composite pattern that contains all the common and specifically expressed proteins from all the cell lines. Significant differences in protein expression, both qualitative and quantitative, were observed not only between normal cells and tumor cells, but also among the tumor cell lines. Eight percent of the consistently detected proteins were found in significantly (P < 0.001) variable levels among the cell lines. Using a combination of immunostaining, comigration with purified protein, subcellular fractionation, and amino-terminal protein sequencing, we identified a subset of the differentially expressed proteins. These identified proteins include the cytoskeletal proteins actin, tubulin, vimentin, and cytokeratins. The cell lines can be classified into four distinct groups based on their intermediate filament protein profile. We also identified heat shock proteins; hsp27, hsp60, and hsp70 varied in abundance and in some cases in the relative phosphorylation levels among the cell lines. Finally, we identified IMP dehydrogenase in each of the cell lines, and found the levels of this enzyme in the tumor cell lines elevated 2- to 20-fold relative to the levels in normal cells.

  15. PHYSIOLOGY AND GENETIC ASPECTS OF THE REGULATION OF EXPRESSION MILK PROTEIN GENES

    Directory of Open Access Journals (Sweden)

    Jozef Bulla

    2013-06-01

    Full Text Available For the genetic improvement of milk composition and milk yield, both the typing of different protein variants and knowledge about the regulation of expression of the different milk protein genes are important. Some of the processing properties of milk are dependent on the milk composition. Information about the DNA sequence and genes involved in the expression of the milk protein genes,therefore,is big importance for genetic improvement of these traits in animals breeding programmes.In recent years more data has become available concerning the regulation of expression of the milk protein genes and as might have been expected from the complex multihormonal control of these genes it appears to be rather complex. Although several mammary gland specific factors that play a role in expression of some of these genes have been identified,none of these factors has been shown to be involved in the expression of all or the majority of the milk protein genes.

  16. Comparison of recombinant protein expression in a baculovirus system in insect cells (Sf9) and silkworm.

    Science.gov (United States)

    Usami, Akihiro; Ishiyama, Seiji; Enomoto, Chiaki; Okazaki, Hironobu; Higuchi, Keiko; Ikeda, Mashahiro; Yamamoto, Takeshi; Sugai, Mutsumi; Ishikawa, Yukiko; Hosaka, Yumiko; Koyama, Teruyuki; Tobita, Yoneko; Ebihara, Syoko; Mochizuki, Toshiko; Asano, Yoshimi; Nagaya, Hidekazu

    2011-02-01

    Using a hybrid baculovirus system, we compared the expression of 45 recombinant proteins from six categories using two models: silkworm (larvae and pupae) and an Sf9 cell line. A total of 45 proteins were successfully expressed; preparation of hybrid baculovirus was unsuccessful for one protein, and two proteins were not expressed. A similar pattern of expression was seen in both silkworm and Sf9 cells, with double and multiple bands found in immunoblotting of the precipitate of both hosts. Degraded proteins were seen only in the silkworm system (particularly in the larvae). Production was more efficient in silkworms; a single silkworm produced about 70 times more protein than 10(6) Sf9 cells in 2 ml of culture medium.

  17. In vivo protein trapping produces a functional expression codex of the vertebrate proteome.

    Science.gov (United States)

    Clark, Karl J; Balciunas, Darius; Pogoda, Hans-Martin; Ding, Yonghe; Westcot, Stephanie E; Bedell, Victoria M; Greenwood, Tammy M; Urban, Mark D; Skuster, Kimberly J; Petzold, Andrew M; Ni, Jun; Nielsen, Aubrey L; Patowary, Ashok; Scaria, Vinod; Sivasubbu, Sridhar; Xu, Xiaolei; Hammerschmidt, Matthias; Ekker, Stephen C

    2011-06-01

    We describe a conditional in vivo protein-trap mutagenesis system that reveals spatiotemporal protein expression dynamics and can be used to assess gene function in the vertebrate Danio rerio. Integration of pGBT-RP2.1 (RP2), a gene-breaking transposon containing a protein trap, efficiently disrupts gene expression with >97% knockdown of normal transcript amounts and simultaneously reports protein expression for each locus. The mutant alleles are revertible in somatic tissues via Cre recombinase or splice-site-blocking morpholinos and are thus to our knowledge the first systematic conditional mutant alleles outside the mouse model. We report a collection of 350 zebrafish lines that include diverse molecular loci. RP2 integrations reveal the complexity of genomic architecture and gene function in a living organism and can provide information on protein subcellular localization. The RP2 mutagenesis system is a step toward a unified 'codex' of protein expression and direct functional annotation of the vertebrate genome.

  18. Stable Drosophila Cell Lines: An Alternative Approach to Exogenous Protein Expression.

    Science.gov (United States)

    Backovic, Marija; Krey, Thomas

    2016-01-01

    Recombinant protein production has become an indispensable tool for various research directions and biotechnological applications in the past decades. Among the numerous reported expression systems, insect cells provide the possibility to produce complex target proteins that require posttranslational modifications. Stable expression in Drosophila S2 cells represents an attractive alternative to the widely used baculovirus expression system, offering important advantages in particular for difficult-to-express proteins, e.g., membrane proteins or heavily glycosylated multi-domain proteins that are stabilized by a complex disulfide pattern. Here we present the methodology that is required for the generation of stable Drosophila S2 cell transfectants and for production of recombinant proteins using those transfectants.

  19. Changes in protein expression due to deleterious mutations in the FA/BRCA pathway.

    Science.gov (United States)

    Salles, Daniela; Cabral, Rosa Estela Caseira; Pizzatti, Luciana; Bisch, Paulo M; Paixão, Julio Cesar; de Almeida, Carlos Eduardo Bonacossa; Seuánez, Héctor N; Cabral-Neto, Januario Bispo

    2007-12-28

    Inherited deleterious mutations in one of the Fanconi anemia genes lead to a disease, characterized by bone marrow failure, myeloid leukemia, and hypersensitivity to DNA damage. We identified proteins likely associated to the molecular signaling pathways involved in DNA repair of interstrand cross-link lesions and in mechanisms of genomic stability mediated by FA/BRCA pathways. We compared protein maps resolved by bidimensional electrophoresis and analyzed differentially expressed proteins, by mass spectrometry, between FA complementation group C (FANCC)-deficient cells, and their ectopically corrected counterpart in physiological conditions or after treatment with MMC. We found six differentially expressed proteins; among them, the checkpoint mediator protein MDC1 whose expression was disrupted in FANCC-/- cells. The potential role of differentially expressed proteins in FA phenotype is discussed.

  20. THE EXPRESSION OF P53 PROTEIN AND P21WAFl/cipl/sdil IN GASTRIC CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To study the relation along p53, p21 protein, p21 gene and their clinical significances in 40 gastric comparing with normal gastric tissues.Methods In this study, the p53 and p21 protein were investigated in 40 gastric carcinomas using IHC(Immunohistochemistry). At the same time, the possible presence of p21 gene mutation was also analyzed by silver staining PCR-SSCP method.Results The abnormal expression of p53 and p21 protein occurs only in gastric carcinoma; The expression of p53 protein and p21 is not related to the clinico pathological features. There was relationship between the expression of p53 protein and p21 protein. In 40 cases of gastric carcinoma, single strand conformational polymorphism of PCR product for p21 gene in tumor tissue shows no altered band or mobility shifting.Conclusion The abnormal expression of p53 and p21 protein occurs only in gastric carcinoma and is not related to the clinicopathological features. The expression of p21 protein is related to that of p53 protein. The mutation of p21 gene was not found in all of 40 tumor specimens. This suggests that p21 alteration in gastric carcinoma is caused through the inactivation of p53 protein rather than through intragenic mutation of the p21 gene itself.Using drugs which can stimulate p21 gene is a new method to cure gastric cancer with mutation-p53 protein.

  1. Expression and purification of recombinant proteins in Escherichia coli tagged with a small metal-binding protein from Nitrosomonas europaea.

    Science.gov (United States)

    Vargas-Cortez, Teresa; Morones-Ramirez, Jose Ruben; Balderas-Renteria, Isaias; Zarate, Xristo

    2016-02-01

    Escherichia coli is still the preferred organism for large-scale production of recombinant proteins. The use of fusion proteins has helped considerably in enhancing the solubility of heterologous proteins and their purification with affinity chromatography. Here, the use of a small metal-binding protein (SmbP) from Nitrosomonas europaea is described as a new fusion protein for protein expression and purification in E. coli. Fluorescent proteins tagged at the N-terminal with SmbP showed high levels of solubility, compared with those of maltose-binding protein and glutathione S-transferase, and low formation of inclusion bodies. Using commercially available IMAC resins charged with Ni(II), highly pure recombinant proteins were obtained after just one chromatography step. Proteins may be purified from the periplasm of E. coli if SmbP contains the signal sequence at the N-terminal. After removal of the SmbP tag from the protein of interest, high-yields are obtained since SmbP is a protein of just 9.9 kDa. The results here obtained suggest that SmbP is a good alternative as a fusion protein/affinity tag for the production of soluble recombinant proteins in E. coli.

  2. A Bayesian model for classifying all differentially expressed proteins simultaneously in 2D PAGE gels

    Directory of Open Access Journals (Sweden)

    Wu Steven H

    2012-06-01

    Full Text Available Abstract Background Two-dimensional polyacrylamide gel electrophoresis (2D PAGE is commonly used to identify differentially expressed proteins under two or more experimental or observational conditions. Wu et al (2009 developed a univariate probabilistic model which was used to identify differential expression between Case and Control groups, by applying a Likelihood Ratio Test (LRT to each protein on a 2D PAGE. In contrast to commonly used statistical approaches, this model takes into account the two possible causes of missing values in 2D PAGE: either (1 the non-expression of a protein; or (2 a level of expression that falls below the limit of detection. Results We develop a global Bayesian model which extends the previously described model. Unlike the univariate approach, the model reported here is able treat all differentially expressed proteins simultaneously. Whereas each protein is modelled by the univariate likelihood function previously described, several global distributions are used to model the underlying relationship between the parameters associated with individual proteins. These global distributions are able to combine information from each protein to give more accurate estimates of the true parameters. In our implementation of the procedure, all parameters are recovered by Markov chain Monte Carlo (MCMC integration. The 95% highest posterior density (HPD intervals for the marginal posterior distributions are used to determine whether differences in protein expression are due to differences in mean expression intensities, and/or differences in the probabilities of expression. Conclusions Simulation analyses showed that the global model is able to accurately recover the underlying global distributions, and identify more differentially expressed proteins than the simple application of a LRT. Additionally, simulations also indicate that the probability of incorrectly identifying a protein as differentially expressed (i.e., the False

  3. Proteome analysis of differential protein expression in infarcted rat heart after verapamil treatment

    Institute of Scientific and Technical Information of China (English)

    Ying LI; Yi WANG; Haibin QU; Yiyu CHENG

    2009-01-01

    To explore the protein-level mechanism of action verapamil in acute myocardial infarcted rats, the myocardial proteome was analyzed by two-dimensional electrophoresis (2-DE). Compared with the sham-operated group and the infarcted group, the result shows that 8 protein expressions in the verapamil treated group were up-regulated, and 7 protein expressions in this group were down-regulated significantly. Using MALDI-TOF-MS, 15 proteins with significant changes were identified through a database search. These proteins can be divided into 4 groups by their biological function: (1) Energy metabolism and mitochondrial function related proteins; (2) oxidative stress-induced proteins; (3) cytoskeletal Proteins; (4) other proteins. The findings show that the myocardial protective effects of verapamil in the myocardial damage process are related to the recovery of energy supply as well as anti-oxidative stress property.

  4. Aberrant expression of nuclear matrix proteins during HMBA-induced differentiation of gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To investigate the aberrant expression of nuclear matrix proteins in human gastric cancer cells before and after hexamethylene bisacetamide (HMBA) treatment.METHODS: Proteomics analysis of differential nuclear matrix proteins was performed by two dimensional electrophoresis polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.The expression levels of three nuclear matrix proteins were further confirmed by Western blotting and their location...

  5. A new method to customize protein expression vectors for fast, efficient and background free parallel cloning

    OpenAIRE

    Scholz, J; Besir, H.; Strasser, C.; Suppmann, S.

    2013-01-01

    Background: Expression and purification of correctly folded proteins typically require screening of different parameters such as protein variants, solubility enhancing tags or expression hosts. Parallel vector series that cover all variations are available, but not without compromise. We have established a fast, efficient and absolutely background free cloning approach that can be applied to any selected vector. Results: Here we describe a method to tailor selected expression vectors for para...

  6. Reishi immuno-modulation protein induces interleukin-2 expression via protein kinase-dependent signaling pathways within human T cells.

    Science.gov (United States)

    Hsu, Hsien-Yeh; Hua, Kuo-Feng; Wu, Wei-Chi; Hsu, Jason; Weng, Shih-Ting; Lin, Tsai-Leng; Liu, Chun-Yi; Hseu, Ruey-Shyang; Huang, Ching-Tsan

    2008-04-01

    Ganoderma lucidum, a medicinal fungus is thought to possess and enhance a variety of human immune functions. An immuno-modulatory protein, Ling Zhi-8 (LZ-8) isolated from G. lucidum exhibited potent mitogenic effects upon human peripheral blood lymphocytes (PBL). However, LZ-8-mediated signal transduction in the regulation of interleukin-2 (IL-2) gene expression within human T cells is largely unknown. Here we cloned the LZ-8 gene of G. lucidum, and expressed the recombinant LZ-8 protein (rLZ-8) by means of a yeast Pichia pastoris protein expression system. We found that rLZ-8 induces IL-2 gene expression via the Src-family protein tyrosine kinase (PTK), via reactive oxygen species (ROS), and differential protein kinase-dependent pathways within human primary T cells and cultured Jurkat T cells. In essence, we have established the nature of the rLZ-8-mediated signal-transduction pathways, such as PTK/protein kinase C (PKC)/ROS, PTK/PLC/PKCalpha/ERK1/2, and PTK/PLC/PKCalpha/p38 pathways in the regulation of IL-2 gene expression within human T cells. Our current results of analyzing rLZ-8-mediated signal transduction in T cells might provide a potential application for rLZ-8 as a pharmacological immune-modulating agent.

  7. The effect of HCV Core protein on the expression of miR-150

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    Sayad Khanizadeh

    2016-09-01

    Full Text Available Background : Hepatitis C virus (HCV is considered as one of the major pathogenic agents of chronic liver diseases. Previous studies have shown that HCV proteins can interaction with gene regulatory networks such as microRNAs. The aim of this study was to investigate the effect of HCV core protein on the expression of miR-150 in a cell culture model. Materials and Methods: Plasmids expressing full HCV core protein was transfected into Huh7 cell lines while a GFP expressing plasmid employed as negative control. Subsequently, total RNA extracted and Real-Time PCR performed to measure the expression level of miR-150 expression. Moreover, trypan blue exclusion assay was performed to investigate the effect of core protein on cell viability. Results: The gene expression analysis of miR-150 in Huh7 cells showed that endogenous HCV core protein could significantly down regulation of miR-150 when compared to GFP control plasmid and normal cells (P<0.01. Beside, core protein induced no significant proliferative or cytotoxic effects on hepatic cells as determined by trypan blue exclusion assay (P<0.05. Conclusion: Our study suggests that HCV core protein can led to down regulation of miR-150 expression. This data revealed that HCV protein interactions with cell regulatory machinery may contribute to pathogenesis of chronic liver diseases.

  8. A novel method for increasing the expression level of recombinant proteins.

    Science.gov (United States)

    Wang, Aijun; Clapper, Jonathan; Guderian, Jeffery A; Foy, Teresa M; Fanger, Gary R; Retter, Marc W; Skeiky, Yasir A W

    2003-07-01

    Expression of recombinant proteins is an important step towards elucidating the functions of many genes discovered through genomic sequencing projects. It is also critical for validating gene targets and for developing effective therapies for many diseases. Here we describe a novel method to express recombinant proteins that are extremely difficult to produce otherwise. The increased protein expression level is achieved by using a fusion partner, MTB32-C, which is the carboxyl terminal fragment of the Mycobacterium tuberculosis antigen, MTB32 (Rv0125). By fusing MTB32-C to the N-termini of target genes, we have demonstrated significant enhancement of recombinant protein expression level in Escherichia coli. The inclusion of a 6xHis tag and the 128-amino acid of MTB32-C will add 13.5 kDa to the fusion molecule. Comparison of the mRNA levels of the fusion and non-fusion proteins indicated that the increased fusion protein expression may be regulated at translational or post-translational steps. There are many potential applications for the generated fusion proteins. For example, MTB32-C fusion proteins have been used successfully as immunogens to generate both polyclonal and monoclonal antibodies. These antibodies have been used to characterize cellular localization of the proteins and to validate gene targets at protein level. In addition, these antibodies may be useful in diagnostic and therapeutic applications for many diseases. If desired, the MTB32-C portion in the fusion protein can be removed after protein expression, making it possible to study protein structure and function as well as to screen for potential drugs. Thus, this novel fusion expression system has become a powerful tool for many applications.

  9. Expression, purification, and immobilization of recombinant tamavidin 2 fusion proteins.

    Science.gov (United States)

    Takakura, Yoshimitsu; Oka, Naomi; Tsunashima, Masako

    2014-01-01

    Tamavidin 2 is a fungal avidin-like protein that binds biotin with high affinity. Unlike avidin or streptavidin, tamavidin 2 in soluble form is produced at high levels in Escherichia coli. In this chapter, we describe a method for immobilization and purification of recombinant proteins with the use of tamavidin 2 as an affinity tag. The protein fused to tamavidin 2 is tightly immobilized and simultaneously purified on biotinylated magnetic microbeads without loss of activity.

  10. The DNA base excision repair protein Ape1/Ref-1 as a therapeutic and chemopreventive target.

    Science.gov (United States)

    Fishel, Melissa L; Kelley, Mark R

    2007-01-01

    With our growing understanding of the pathways involved in cell proliferation and signaling, targeted therapies, in the treatment of cancer are entering the clinical arena. New and emerging targets are proteins involved in DNA repair pathways. Inhibition of various proteins in the DNA repair pathways sensitizes cancer cells to DNA damaging agents such as chemotherapy and/or radiation. We study the apurinic endonuclease 1/redox factor-1 (Ape1/Ref-1) and believe that its crucial function in DNA repair and reduction-oxidation or redox signaling make it an excellent target for sensitizing tumor cells to chemotherapy. Ape1/Ref-1 is an essential enzyme in the base excision repair (BER) pathway which is responsible for the repair of DNA caused by oxidative and alkylation damage. As importantly, Ape1/Ref-1 also functions as a redox factor maintaining transcription factors in an active reduced state. Ape1/Ref-1 stimulates the DNA binding activity of numerous transcription factors that are involved in cancer promotion and progression such as AP-1 (Fos/Jun), NFkappaB, HIF-1alpha, CREB, p53 and others. We will discuss what is known regarding the pharmacological targeting of the DNA repair activity, as well as the redox activity of Ape1/Ref-1, and explore the budding clinical utility of inhibition of either of these functions in cancer treatment. A brief discussion of the effect of polymorphisms in its DNA sequence is included because of Ape1/Ref-1's importance to maintenance and integrity of the genome. Experimental modification of Ape1/Ref-1 activity changes the response of cells and of organisms to DNA damaging agents, suggesting that Ape1/Ref-1 may also be a productive target of chemoprevention. In this review, we will provide an overview of Ape1/Ref-1's activities and explore the potential of this protein as a target in cancer treatment as well as its role in chemoprevention.

  11. Differential expression of Yes-associated protein and phosphorylated Yes-associated protein is correlated with expression of Ki-67 and phospho-ERK in colorectal adenocarcinoma.

    Science.gov (United States)

    Kim, Dong-Hoon; Kim, Seok-Hyung; Lee, Ok-Jun; Huang, Song-Mei; Kwon, Ju-Lee; Kim, Jin Man; Kim, Ji-Yeon; Seong, In Ock; Song, Kyu Sang; Kim, Kyung-Hee

    2013-11-01

    Yes-associated protein (YAP) is a transcriptional co-activator and functions as a nuclear downstream effector of the Hippo pathway. Differential expression of YAP and phosphorylated Yes-associated protein (pYAP), which are involved in the expression of Ki-67 and phosphorylated extracellular signal-regulated kinase (pERK) in colorectal adenocarcinoma (CRAC), is not clear. Herein, we hypothesized that nuclear expression of YAP could predict cell proliferation and poor prognosis, while cytoplasmic expression of pYAP would show a reverse correlation with cell proliferation. Paraffin-embedded samples from 144 CRAC patients were studied using immunohistochemistry for YAP, pYAP, Ki-67 and pERK. Frozen samples from 20 CRAC patients were examined for YAP mRNA in tumor and non-tumor tissues, using quantitative real-time PCR. High nuclear YAP expression coincided with high Ki-67 expression (P=0.002). The high nuclear YAP expression group tended to display a poor overall and disease-free survival (P=0.089 and P=0.089, respectively), but YAP mRNA levels in the 20 CRAC tissues were not significantly different in comparison with the 20 non-tumor tissues (P=0.929). We observed an inverse correlation between high cytoplasmic pYAP expression and high Ki-67 expression (P=0.001). Nuclear pERK expression was positively correlated with nuclear YAP expression, but negatively correlated with cytoplasmic pYAP expression (P=0.017 and P=0.020, respectively). Activated nuclear YAP and inactivated cytoplasmic pYAP in CRAC showed a positive correlation with Ki-67 and nuclear pERK expression, suggesting that the expression of YAP and pYAP is a possible predictor of tumor cell proliferation and prognosis in CRAC.

  12. Arabidopsis mRNA polyadenylation machinery: comprehensive analysis of protein-protein interactions and gene expression profiling

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    Mo Min

    2008-05-01

    Full Text Available Abstract Background The polyadenylation of mRNA is one of the critical processing steps during expression of almost all eukaryotic genes. It is tightly integrated with transcription, particularly its termination, as well as other RNA processing events, i.e. capping and splicing. The poly(A tail protects the mRNA from unregulated degradation, and it is required for nuclear export and translation initiation. In recent years, it has been demonstrated that the polyadenylation process is also involved in the regulation of gene expression. The polyadenylation process requires two components, the cis-elements on the mRNA and a group of protein factors that recognize the cis-elements and produce the poly(A tail. Here we report a comprehensive pairwise protein-protein interaction mapping and gene expression profiling of the mRNA polyadenylation protein machinery in Arabidopsis. Results By protein sequence homology search using human and yeast polyadenylation factors, we identified 28 proteins that may be components of Arabidopsis polyadenylation machinery. To elucidate the protein network and their functions, we first tested their protein-protein interaction profiles. Out of 320 pair-wise protein-protein interaction assays done using the yeast two-hybrid system, 56 (~17% showed positive interactions. 15 of these interactions were further tested, and all were confirmed by co-immunoprecipitation and/or in vitro co-purification. These interactions organize into three distinct hubs involving the Arabidopsis polyadenylation factors. These hubs are centered around AtCPSF100, AtCLPS, and AtFIPS. The first two are similar to complexes seen in mammals, while the third one stands out as unique to plants. When comparing the gene expression profiles extracted from publicly available microarray datasets, some of the polyadenylation related genes showed tissue-specific expression, suggestive of potential different polyadenylation complex configurations. Conclusion An

  13. Construction of Prokaryotic Expression Plasmid of mtrC Protein of Neisseria gonorrhoeae and Its Expression in E. Coli

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In order to provide a rational research basis for detection of resistance of Neisseria gonorrhoeae to antimicrobial hydrophobic agents and study on the resistant mechanism of multiple transferable resistance (mtr) efflux system, plasmid pET-28a(+) encoding mtrC gene was constructed and the related target protein was expressed in Escherichia coli (E. coli) DE3. The fragments of mtrC gene of Neisseria gonorrhoeae from the standard strains were amplified and cloned into prokaryotic expression plasmid pET-28a(+) with restriction endonuclease to construct recombinant pET-mtrC which was verified by restriction endonuclease and DNA sequencing. The recombinant was transformed into E. coli DE3 to express the protein mtrC induced by IPTG. The results showed mtrC DNA fragment was proved correct through restriction endonuclease and DNA sequencing. Its sequence was 99.5 % homologus to that published on GeneBank (U14993). A 48.5 kD fusion protein which was induced by IPTG was detected by SDS-PAGE. It was concluded that the construction of prokaryotic expression plasmid of mtrC protein of Neisseria gonorrhoeae was correct and the fusion protein was successively expressed in E. coli.

  14. Clinical significance and prognostic value of Nek2 protein expression in colon cancer.

    Science.gov (United States)

    Lu, Lei; Zhai, Xiaofeng; Yuan, Ronghua

    2015-01-01

    To determine the expression of NIMA-related kinase NEK2 and evaluate its clinical value in colon cancer. Sixty specimens of colon cancer, 30 specimens of paracancerous colon tissues and 10 specimens of normal colon tissues conventionally resected in surgery at the Second Affiliated Hospital of Nantong University from February 2006 to February 2014 were collected. These tissues were detected for the expression of Nek2 using Western Blot and immunohistochemical staining. The relationship between Nek2 protein expression and the clinicopathology and prognosis of colon tissues was discussed. The expression level and positive expression rate of Nek2 protein in the colon cancer were obviously higher than that in the paracancerous tissues and normal colon tissues. They were also significantly higher in the paracancerous tissues than in the normal tissues (PTNM staging (P=0.000), lymph node metastasis (P=0.022) and tumor invasion (P=0.011). With the plotting of Kaplan-Meier survival curve, it could be seen that Nek2 protein expression was not significantly correlated with survival (P=0.0048). High Nek2 protein expression may be an independent risk factor for colon cancer (HR=0.227, 95% CI 0.101-0.510). High Nek2 protein expression reflects the malignant behavior of colon cancer. Playing important roles in the occurrence of colon cancer, Nek2 protein expression has diagnostic and prognostic value in colon cancer.

  15. Effects of cell-cycle-dependent expression on random fluctuations in protein levels.

    Science.gov (United States)

    Soltani, Mohammad; Singh, Abhyudai

    2016-12-01

    Expression of many genes varies as a cell transitions through different cell-cycle stages. How coupling between stochastic expression and cell cycle impacts cell-to-cell variability (noise) in the level of protein is not well understood. We analyse a model where a stable protein is synthesized in random bursts, and the frequency with which bursts occur varies within the cell cycle. Formulae quantifying the extent of fluctuations in the protein copy number are derived and decomposed into components arising from the cell cycle and stochastic processes. The latter stochastic component represents contributions from bursty expression and errors incurred during partitioning of molecules between daughter cells. These formulae reveal an interesting trade-off: cell-cycle dependencies that amplify the noise contribution from bursty expression also attenuate the contribution from partitioning errors. We investigate the existence of optimum strategies for coupling expression to the cell cycle that minimize the stochastic component. Intriguingly, results show that a zero production rate throughout the cell cycle, with expression only occurring just before cell division, minimizes noise from bursty expression for a fixed mean protein level. By contrast, the optimal strategy in the case of partitioning errors is to make the protein just after cell division. We provide examples of regulatory proteins that are expressed only towards the end of the cell cycle, and argue that such strategies enhance robustness of cell-cycle decisions to the intrinsic stochasticity of gene expression.

  16. Proteomic analysis of differentially expressed proteins in Penaeus monodon hemocytes after Vibrio harveyi infection

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    Fang Lo Chu

    2010-07-01

    Full Text Available Abstract Background Viral and bacterial diseases can cause mass mortalities in commercial shrimp aquaculture. In contrast to studies on the antiviral response, the responses of shrimps to bacterial infections by high throughput techniques have been reported only at the transcriptional level and not at the translational level. In this study, a proteomic analysis of shrimp hemocytes to identify differentially expressed proteins in response to a luminous bacterium Vibrio harveyi was evaluated for its feasibility and is reported for the first time. Results The two-dimensional gel electrophoresis (2-DE patterns of the hemocyte proteins from the unchallenged and V. harveyi challenged shrimp, Penaeus monodon, at 24 and 48 h post infection were compared. From this, 27 differentially expressed protein spots, and a further 12 weakly to non-differentially regulated control spots, were selected for further analyses by the LC-ESI-MS/MS. The 21 differentially expressed proteins that could be identified by homologous annotation were comprised of proteins that are directly involved in the host defense responses, such as hemocyanin, prophenoloxidase, serine proteinase-like protein, heat shock protein 90 and alpha-2-macroglobulin, and those involved in signal transduction, such as the14-3-3 protein epsilon and calmodulin. Western blot analysis confirmed the up-regulation of hemocyanin expression upon bacterial infection. The expression of the selected proteins which were the representatives of the down-regulated proteins (the 14-3-3 protein epsilon and alpha-2-macroglobulin and of the up-regulated proteins (hemocyanin was further assessed at the transcription level using real-time RT-PCR. Conclusions This work suggests the usefulness of a proteomic approach to the study of shrimp immunity and revealed hemocyte proteins whose expression were up regulated upon V. harveyi infection such as hemocyanin, arginine kinase and down regulated such as alpha-2-macroglobulin

  17. [Cloning and expression of the prokaryotic expression vectors of phytoplasma immunodominant membrane protein A and preparation of its antiserum].

    Science.gov (United States)

    Liang, Nannan; Zhang, Lijun; Zhao, Haiquan; Liu, Zhongjian; Luo, Huanliang; Lin, Yanxing; Liu, Xiaoxiao

    2013-06-01

    To construct the prokaryotic expression vector of phytoplasma immunodominant membrane protein A (IdpA) in prokaryotic cell, express and purify the IdpA and prepare its antiserum. With the recombinant plasmid pMD18-T-IdpA as templates, IdpA gene was amplified by PCR and cloned into prokaryotic expression vector pET-28a(+) by endonuclease reaction and T4 DNA ligase reaction. Then the recombinant plasmid pET-28a(+)-IdpA was transformed into E.coli BL21 (DE3). After confirmed by PCR and double enzyme digestion, the recombinant protein IdpA was expressed under IPTG induction and purified. The purified product was used to immunize BALB/c mice to prepare its antiserum. IdpA-specific mouse antiserum was identified by ELISA and Westerrn blotting. The prokaryotic vectors of pET-28a(+)-IdpA were constructed successfully and the recombinant protein IdpA was induced to express stably in the E.coli BL21. The purity of IdpA was up to over 90%. In the BALB/c mice immunized by the purified IdpA, the titre of IdpA-specific antiserum was as high as 1:320 000. The recombinant protein IdpA was expressed successfully in E.coli and the IdpA-specific antiserum was prepared.

  18. Heterologous expression of Translocated promoter region protein, Tpr, identified as a transcription factor from Rattus norvegicus.

    Science.gov (United States)

    Agarwal, Shivani; Yadav, Sunita Kumari; Dixit, Aparna

    2011-05-01

    Our earlier studies have demonstrated that the 35 kDa isoform of Translocated promoter region protein (Tpr) of Rattus norvegicus was able to augment c-jun transcription efficiently. Identification of direct targets that may in part downregulate c-jun transcription might prove to be an ideal target to curtail the proliferation of normal cells under pathophysiological conditions. In order to evaluate its potential as a pharmaceutical target, the protein must be produced and purified in sufficiently high yields. In the present study, we report the high level expression of Tpr protein of R. norvegicus employing heterologous host, Escherichia coli, to permit its structural characterization in great detail. We here demonstrate that the Tpr protein was expressed in soluble form and approximately 90 mg/L of the purified protein at the shake flask level could be achieved to near homogeneity using single step-metal chelate affinity chromatography. The amino acid sequence of the protein was confirmed by mass spectroscopic analysis. The highly unstable and disordered Tpr protein was imparted structural and functional stability by the addition of glycerol and it has been shown that the natively unfolded Tpr protein retains DNA binding ability under these conditions only. Thus, the present study emphasizes the significance of an efficient prokaryotic system, which results in a high level soluble expression of a DNA binding protein of eukaryotic origin. Thus, the present strategy employed for purification of the R. norvegicus Tpr protein bypasses the need for the tedious expression strategies associated with the eukaryotic expression systems.

  19. Protein A-mouse acidic mammalian chitinase-V5-His expressed in periplasmic space of Escherichia coli possesses chitinase functions comparable to CHO-expressed protein.

    Directory of Open Access Journals (Sweden)

    Akinori Kashimura

    Full Text Available Acidic mammalian chitinase (AMCase has been shown to be associated with asthma in mouse models, allergic inflammation and food processing. Here, we describe an E. coli-expression system that allows for the periplasmic production of active AMCase fused to Protein A at the N-terminus and V5 epitope and (His6 tag (V5-His at the C-terminus (Protein A-AMCase-V5-His in E. coli. The mouse AMCase cDNA was cloned into the vector pEZZ18, which is an expression vector containing the Staphylococcus Protein A promoter, with the signal sequence and truncated form of Protein A for extracellular expression in E. coli. Most of the Protein A-AMCase-V5-His was present in the periplasmic space with chitinolytic activity, which was measured using a chromogenic substrate, 4-nitrophenyl N,N'-diacetyl-β-D-chitobioside. The Protein A-AMCase-V5-His was purified from periplasmic fractions using an IgG Sepharose column followed by a Ni Sepharose chromatography. The recombinant protein showed a robust peak of activity with a maximum observed activity at pH 2.0, where an optimal temperature was 54°C. When this protein was preincubated between pH 1.0 and pH 11.0 on ice for 1 h, full chitinolytic activity was retained. This protein was also heat-stable till 54°C, both at pH 2.0 and 7.0. The chitinolytic activity of the recombinant AMCase against 4-nitrophenyl N,N'-diacetyl-β-D-chitobioside was comparable to the CHO-expressed AMCase. Furthermore, the recombinant AMCase bound to chitin beads, cleaved colloidal chitin and released mainly N,N'-diacetylchitobiose fragments. Thus, the E. coli-expressed Protein A-mouse AMCase-V5-His fusion protein possesses chitinase functions comparable to the CHO-expressed AMCase. This recombinant protein can be used to elucidate detailed biomedical functions of the mouse AMCase.

  20. Schisandrin B protects PC12 cells by decreasing the expression of amyloid precursor protein and vacuolar protein sorting 35.

    Science.gov (United States)

    Yan, Mingmin; Mao, Shanping; Dong, Huimin; Liu, Baohui; Zhang, Qian; Pan, Gaofeng; Fu, Zhiping

    2012-03-25

    PC12 cell injury was induced using 20 μM amyloid β-protein 25-35 to establish a model of Alzheimer's disease. The cells were then treated with 5, 10, and 25 μM Schisandrin B. Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25-35 gradually increased and the rate of apoptosis gradually decreased. Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased. Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change. These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25-35 in a dose-dependent manner. This may be caused by decreasing the expression of vacuolar protein sorting 35 and amyloid precursor protein.

  1. Affinity Purification of a Recombinant Protein Expressed as a Fusion with the Maltose-Binding Protein (MBP) Tag

    Science.gov (United States)

    Duong-Ly, Krisna C.; Gabelli, Sandra B.

    2015-01-01

    Expression of fusion proteins such as MBP fusions can be used as a way to improve the solubility of the expressed protein in E. coli (Fox and Waugh, 2003; Nallamsetty et al., 2005; Nallamsetty and Waugh, 2006) and as a way to introduce an affinity purification tag. The protocol that follows was designed by the authors as a first step in the purification of a recombinant protein fused with MBP, using fast protein liquid chromatography (FPLC). Cells should have been thawed, resuspended in binding buffer, and lysed by sonication or microfluidization before mixing with the amylose resin or loading on the column. Slight modifications to this protocol may be made to accommodate both the protein of interest and the availability of equipment. PMID:26096500

  2. PepGMV Rep-Protein Expression in Mammalian Cells

    Science.gov (United States)

    Chapa-Oliver, Angela María; Mejía-Teniente, Laura; García-Gasca, Teresa; Guevara-Gonzalez, Ramon Gerardo; Torres-Pacheco, Irineo

    2012-01-01

    The Geminiviruses genome is a small, single strand DNA that replicates in the plant cell nucleus. Analogous to animal DNA viruses, Geminiviruses depend on the host replication machinery to amplify their genomes and only supply the factors required to initiate their replication. Consequently, Geminiviruses remove the cell-cycle arrest and induce the host replication machinery using an endocycle process. They encode proteins, such as the conserved replication-associated proteins (Rep) that interact with retinoblastoma-like proteins in plants and alter the cell division cycle in yeasts. Therefore, the aim of this work is to analyze the impact of Pepper Golden Mosaic Virus (PepGMV) Rep protein in mammalian cells. Results indicate that the pTracer-SV40:Rep construction obtained in this work can be used to analyze the Rep protein effect in mammalian cells in order to compare the cell cycle regulation mechanisms in plants and animals. PMID:23170183

  3. Changes in ovarian protein expression during primordial follicle formation in the hamster.

    Science.gov (United States)

    Mukherjee, Anindit; Reisdorph, Nichole; Guda, Chttibabu; Pandey, Sanjit; Roy, Shyamal K

    2012-01-02

    Although many proteins have been shown to affect the transition of primordial follicles to the primary stage, factors regulating the formation of primordial follicles remains sketchy at best. Differentiation of somatic cells into early granulosa cells during ovarian morphogenesis is the hallmark of primordial follicle formation; hence, critical changes are expected in protein expression. We wanted to identify proteins, the expression of which would correlate with the formation of primordial follicles as a first step to determine their biological function in folliculogenesis. Proteins were extracted from embryonic (E15) and 8-day-old (P8) hamster ovaries and fractionated by two-dimensional gel electrophoresis. Gels were stained with Proteosilver, and images of protein profiles corresponding to E15 and P8 ovaries were overlayed to identify protein spots showing altered expression. Some of the protein spots were extracted from SyproRuby-stained preparative gels, digested with trypsin, and analyzed by mass spectrometry. Both E15 and P8 ovaries had high molecular weight proteins at acidic, basic, and neutral ranges; however, we focused on small molecular weight proteins at 4-7 pH range. Many of those spots might represent post-translational modification. Mass spectrometric analysis revealed the identity of these proteins. The formation of primordial follicles on P8 correlated with many differentially and newly expressed proteins. Whereas Ebp1 expression was downregulated in ovarian somatic cells, Sfrs3 expression was specifically upregulated in newly formed granulosa cells of primordial follicles on P8. The results show for the first time that the morphogenesis of primordial follicles in the hamster coincides with altered and novel expression of proteins involved in cell proliferation, transcriptional regulation, and metabolism. Therefore, formation of primordial follicles is an active process requiring differentiation of somatic cells into early granulosa cells and

  4. Intraclonal protein expression heterogeneity in recombinant CHO cells.

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    Warren Pilbrough

    Full Text Available Therapeutic glycoproteins have played a major role in the commercial success of biotechnology in the post-genomic era. But isolating recombinant mammalian cell lines for large-scale production remains costly and time-consuming, due to substantial variation and unpredictable stability of expression amongst transfected cells, requiring extensive clone screening to identify suitable high producers. Streamlining this process is of considerable interest to industry yet the underlying phenomena are still not well understood. Here we examine an antibody-expressing Chinese hamster ovary (CHO clone at single-cell resolution using flow cytometry and vectors, which couple light and heavy chain transcription to fluorescent markers. Expression variation has traditionally been attributed to genetic heterogeneity arising from random genomic integration of vector DNA. It follows that single cell cloning should yield a homogeneous cell population. We show, in fact, that expression in a clone can be surprisingly heterogeneous (standard deviation 50 to 70% of the mean, approaching the level of variation in mixed transfectant pools, and each antibody chain varies in tandem. Phenotypic variation is fully developed within just 18 days of cloning, yet is not entirely explained by measurement noise, cell size, or the cell cycle. By monitoring the dynamic response of subpopulations and subclones, we show that cells also undergo slow stochastic fluctuations in expression (half-life 2 to 11 generations. Non-genetic diversity may therefore play a greater role in clonal variation than previously thought. This also has unexpected implications for expression stability. Stochastic gene expression noise and selection bias lead to perturbations from steady state at the time of cloning. The resulting transient response as clones reestablish their expression distribution is not ordinarily accounted for but can contribute to declines in median expression over timescales of up to 50

  5. Intraclonal Protein Expression Heterogeneity in Recombinant CHO Cells

    Science.gov (United States)

    Pilbrough, Warren; Munro, Trent P.; Gray, Peter

    2009-01-01

    Therapeutic glycoproteins have played a major role in the commercial success of biotechnology in the post-genomic era. But isolating recombinant mammalian cell lines for large-scale production remains costly and time-consuming, due to substantial variation and unpredictable stability of expression amongst transfected cells, requiring extensive clone screening to identify suitable high producers. Streamlining this process is of considerable interest to industry yet the underlying phenomena are still not well understood. Here we examine an antibody-expressing Chinese hamster ovary (CHO) clone at single-cell resolution using flow cytometry and vectors, which couple light and heavy chain transcription to fluorescent markers. Expression variation has traditionally been attributed to genetic heterogeneity arising from random genomic integration of vector DNA. It follows that single cell cloning should yield a homogeneous cell population. We show, in fact, that expression in a clone can be surprisingly heterogeneous (standard deviation 50 to 70% of the mean), approaching the level of variation in mixed transfectant pools, and each antibody chain varies in tandem. Phenotypic variation is fully developed within just 18 days of cloning, yet is not entirely explained by measurement noise, cell size, or the cell cycle. By monitoring the dynamic response of subpopulations and subclones, we show that cells also undergo slow stochastic fluctuations in expression (half-life 2 to 11 generations). Non-genetic diversity may therefore play a greater role in clonal variation than previously thought. This also has unexpected implications for expression stability. Stochastic gene expression noise and selection bias lead to perturbations from steady state at the time of cloning. The resulting transient response as clones reestablish their expression distribution is not ordinarily accounted for but can contribute to declines in median expression over timescales of up to 50 days. Noise

  6. Heat shock protein 27 expression in the human testis showing normal and abnormal spermatogenesis.

    Science.gov (United States)

    Adly, Mohamed A; Assaf, Hanan A; Hussein, Mahmoud Rezk A

    2008-10-01

    Heat shock proteins (HSPs) are molecular chaperones involved in protein folding, assembly and transport, and which play critical roles in the regulation of cell growth, survival and differentiation. We set out to test the hypothesis that HSP27 protein is expressed in the human testes and its expression varies with the state of spermatogenesis. HSP27 expression was examined in 30 human testicular biopsy specimens (normal spermatogenesis, maturation arrest and Sertoli cell only syndrome, 10 cases each) using immunofluorescent methods. The biopsies were obtained from patients undergoing investigations for infertility. The seminiferous epithelium of the human testes showing normal spermatogenesis had a cell type-specific expression of HSP27. HSP27 expression was strong in the cytoplasm of the Sertoli cells, spermatogonia, and Leydig cells. Alternatively, the expression was moderate in the spermatocytes, weak in the spermatids and absent in the spermatozoa. In testes showing maturation arrest, HSP27 expression was strong in the Sertoli cells, weak in the spermatogonia, and spermatocytes. It was absent in the spermatids and Leydig cells. In Sertoli cell only syndrome, HSP27 expression was strong in the Sertoli cells and absent in the Leydig cells. We report for the first time the expression patterns of HSP27 in the human testes and show differential expression during normal spermatogenesis, indicating a possible role in this process. The altered expression of this protein in testes showing abnormal spermatogenesis may be related to the pathogenesis of male infertility.

  7. Cell-Free Expression of Protein Kinase A for Rapid Activity Assays

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    Donna M. Leippe

    2010-05-01

    Full Text Available Functional protein analysis often calls for lengthy, laborious in vivo protein expression and purification, and can be complicated by the lack of stability of the purified protein. In this study, we demonstrate the feasibility of a simplified procedure for functional protein analysis on magnetic particles using cell-free protein synthesis of the catalytic subunit of human cAMP-dependent protein kinase as a HaloTag® fusion protein. The cell-free protein synthesis systems provide quick access to the protein of interest, while the HaloTag technology provides efficient, covalent protein immobilization of the fusion protein, eliminating the need for further protein purification and minimizing storage-related stability issues. The immobilized cPKA fusion protein is assayed directly on magnetic beads and can be used in inhibitor analyses. The combination of rapid protein synthesis and capture technologies can greatly facilitate the process of protein expression and activity screening, and therefore, can become a valuable tool for functional proteomics studies.

  8. Expression of Beta-Catenin and APC Protein in Ovarian Epithelial Tumor and Its Implication

    Institute of Scientific and Technical Information of China (English)

    LIN Xiao; LI Yu; MI Can

    2007-01-01

    Objective: To investigate the expression of beta-catenin, APC protein and its implication in ovarian epithelial tumor. Methods: Immunohistochemical staining with SP method was conducted to determine the expression of beta-catenin and APC protein in 48 cases of ovarian epithelial tumor. Results: The abnormal expression rates of beta-catenin in ovarian malignant and borderline epithelial tumors were higher than that in benign epithelial tumors. The expression of APC protein in benign epithelial tumors was significantly greater than that in malignant epithelial tumors. A significant negative correlation was found between beta-catenin and APC protein in ovarian epithelial tumors. Conclusion: Beta-catenin and APC protein have important effect on pathogenesis and development of ovarian epithelial tumors.

  9. Immunohistochemical expression of Skp2 protein in oral nevi and melanoma

    Science.gov (United States)

    León, Jorge E.; Carlos, Román; Delgado-Azañero, Wilson; Mosqueda-Taylor, Adalberto; Paes-de-Almeida, Oslei

    2013-01-01

    Objective: The aim of this study was to analyze the immunohistochemical expression of Skp2 protein in 38 oral nevi and 11 primary oral melanomas. Study Design: Expression of this ubiquitin protein was evaluated by immunohistochemistry in 49 oral melanocytic lesions, including 38 intramucosal nevi and 11 primary oral melanomas. The labeling index (LI) was assessed considering the percentage of cells expressing nuclear positivity out of the total number of cells, counting 1000 cells per slide. Results: Skp2 protein was rarely expressed in intramucosal nevi, in contrast to oral melanomas, which showed high levels of this protein. Conclusion: These results indicate that Skp2 protein may play a role in the development and progression of oral melanomas, and it also could be useful as an immunohistochemical marker for differential diagnosis of oral benign and malignant melanocytic lesions. Key words:Oral melanoma, oral nevi, Skp2, cell cycle, immunohistochemistry. PMID:23385514

  10. 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.

  11. Effect of Helicobacter pylori infection on Bax protein expression in patients with gastric precancerous lesions

    Institute of Scientific and Technical Information of China (English)

    Hai-Feng Liu; Wei-Wen Liu; Guo-An Wang; Xiao-Chun Teng

    2005-01-01

    AIM: To investigate the effect of Helicobacter pylori (H pylori) infection on Bax protein expression, and explore the role of H pylori in gastric carcinogenesis.METHODS: H pylori was assessed by rapid urease test and Warthin-Starry method, and expression of Bax protein was examined immunohistochemically in 72 patients with pre-malignant lesions.RESULTS: Bax protein was differently expressed in intestinal metaplasia and gastric dysplasia, and showed 63.99% positivity. The positivity of Bax protein expression in H pylori-positive gastric precancerous lesions (72.3%) was significantly higher than that in H pylori-negative gastric precancerous lesions (48.0%, χ2 = 4.191, P<0.05).H pylori infection was well correlated with the expression of Bax protein in gastric precancerous lesions (r = 0.978,P<0.01). After eradication of H pylori, the positivity of Bax protein expression significantly decreased in H pylori-positive gastric precancerous lesions (χ2= 5.506,P<0.05). In the persisting H pylori-infected patients,the positivity of Bax protein expression was not changed.CONCLUSION: H pylori infection may be involved in the upregulation of Bax gene, which might be one of the mechanisms of H pylori infection-induced gastric epithelial cell apoptosis. H pylori might act as a tumor promoter in the genesis of gastric carcinoma and eradication of H pylori could inhibit gastric carcinogenesis.

  12. Heat-resistant protein expression during germination of maize seeds under water stress.

    Science.gov (United States)

    Abreu, V M; Silva Neta, I C; Von Pinho, E V R; Naves, G M F; Guimarães, R M; Santos, H O; Von Pinho, R G

    2016-08-12

    Low water availability is one of the factors that limit agricultural crop development, and hence the development of genotypes with increased water stress tolerance is a challenge in plant breeding programs. Heat-resistant proteins have been widely studied, and are reported to participate in various developmental processes and to accumulate in response to stress. This study aimed to evaluate heat-resistant protein expression under water stress conditions during the germination of maize seed inbreed lines differing in their water stress tolerance. Maize seed lines 91 and 64 were soaked in 0, -0.3, -0.6, and -0.9 MPa water potential for 0, 6, 12, 18, and 24 h. Line 91 is considered more water stress-tolerant than line 64. The analysis of heat-resistant protein expression was made by gel electrophoresis and spectrophotometry. In general, higher expression of heat-resistant proteins was observed in seeds from line 64 subjected to shorter soaking periods and lower water potentials. However, in the water stress-tolerant line 91, a higher expression was observed in seeds that were subjected to -0.3 and -0.6 MPa water potentials. In the absence of water stress, heat-resistant protein expression was reduced with increasing soaking period. Thus, there was a difference in heat-resistant protein expression among the seed lines differing in water stress tolerance. Increased heat-resistant protein expression was observed in seeds from line 91 when subjected to water stress conditions for longer soaking periods.

  13. Expression and affinity purification of recombinant proteins from plants

    Science.gov (United States)

    Desai, Urvee A.; Sur, Gargi; Daunert, Sylvia; Babbitt, Ruth; Li, Qingshun

    2002-01-01

    With recent advances in plant biotechnology, transgenic plants have been targeted as an inexpensive means for the mass production of proteins for biopharmaceutical and industrial uses. However, the current plant purification techniques lack a generally applicable, economic, large-scale strategy. In this study, we demonstrate the purification of a model protein, beta-glucuronidase (GUS), by employing the protein calmodulin (CaM) as an affinity tag. In the proposed system, CaM is fused to GUS. In the presence of calcium, the calmodulin fusion protein binds specifically to a phenothiazine-modified surface of an affinity column. When calcium is removed with a complexing agent, e.g., EDTA, calmodulin undergoes a conformational change allowing the dissociation of the calmodulin-phenothiazine complex and, therefore, permitting the elution of the GUS-CaM fusion protein. The advantages of this approach are the fast, efficient, and economical isolation of the target protein under mild elution conditions, thus preserving the activity of the target protein. Two types of transformation methods were used in this study, namely, the Agrobacterium-mediated system and the viral-vector-mediated transformation system. Copyright 2002 Elsevier Science (USA).

  14. Protein expression changes in breast cancer and their importance

    Directory of Open Access Journals (Sweden)

    Tuğba Semerci Sevimli

    2013-03-01

    Full Text Available Studies about nucleic acids have increased after thepublication of DNA’s three dimensional structure by Watsonand Crick. Nucleic acids are the heritable moleculeswhich contain codes for proteins. Proteins are the mostimportant elements in molecular world because they arethe basic structural and functional components of a livingorganism. Clarifying the celluler events that involve proteinsare important in many areas for example diagnosisand treatment determination of diseases or developmentof new drugs. Proteome that comes from a combinationof the terms protein and genome, is one of the importantfield in these days. The studies in this area have acceleratedand gained a different place especially with afterthe completion of human genome project. In synthesis ofa protein just only genetic information is not enough. Atthe same time the change or changes of a protein afterthe synthesis, the final version and transporting to finallocalization of it also important. Because having defects inmailing cells of breast cancer, the first targets of treatmentmust be proteins. In this way the studies on proteins areimportant to determine prognostic and diagnostic diseasemarkers and also significant for identifying new treatmentstrategies.Key words: Genom, proteom, breast cancer

  15. Stochastic protein expression in individual cells at the single molecule level

    Science.gov (United States)

    Cai, Long; Friedman, Nir; Xie, X. Sunney

    2006-03-01

    In a living cell, gene expression-the transcription of DNA to messenger RNA followed by translation to protein-occurs stochastically, as a consequence of the low copy number of DNA and mRNA molecules involved. These stochastic events of protein production are difficult to observe directly with measurements on large ensembles of cells owing to lack of synchronization among cells. Measurements so far on single cells lack the sensitivity to resolve individual events of protein production. Here we demonstrate a microfluidic-based assay that allows real-time observation of the expression of β-galactosidase in living Escherichia coli cells with single molecule sensitivity. We observe that protein production occurs in bursts, with the number of molecules per burst following an exponential distribution. We show that the two key parameters of protein expression-the burst size and frequency-can be either determined directly from real-time monitoring of protein production or extracted from a measurement of the steady-state copy number distribution in a population of cells. Application of this assay to probe gene expression in individual budding yeast and mouse embryonic stem cells demonstrates its generality. Many important proteins are expressed at low levels, and are thus inaccessible by current genomic and proteomic techniques. This microfluidic single cell assay opens up possibilities for system-wide characterization of the expression of these low copy number proteins.

  16. Fast identification of folded human protein domains expressed in E. coli suitable for structural analysis

    Directory of Open Access Journals (Sweden)

    Schlegel Brigitte

    2004-03-01

    Full Text Available Abstract Background High-throughput protein structure analysis of individual protein domains requires analysis of large numbers of expression clones to identify suitable constructs for structure determination. For this purpose, methods need to be implemented for fast and reliable screening of the expressed proteins as early as possible in the overall process from cloning to structure determination. Results 88 different E. coli expression constructs for 17 human protein domains were analysed using high-throughput cloning, purification and folding analysis to obtain candidates suitable for structural analysis. After 96 deep-well microplate expression and automated protein purification, protein domains were directly analysed using 1D 1H-NMR spectroscopy. In addition, analytical hydrophobic interaction chromatography (HIC was used to detect natively folded protein. With these two analytical methods, six constructs (representing two domains were quickly identified as being well folded and suitable for structural analysis. Conclusion The described approach facilitates high-throughput structural analysis. Clones expressing natively folded proteins suitable for NMR structure determination were quickly identified upon small scale expression screening using 1D 1H-NMR and/or analytical HIC. This procedure is especially effective as a fast and inexpensive screen for the 'low hanging fruits' in structural genomics.

  17. Comparative analysis and "expression space" coverage of the production of prokaryotic membrane proteins for structural genomics.

    Science.gov (United States)

    Surade, Sachin; Klein, Markus; Stolt-Bergner, Peggy C; Muenke, Cornelia; Roy, Ankita; Michel, Hartmut

    2006-09-01

    Membrane proteins comprise up to one-third of prokaryotic and eukaryotic genomes, but only a very small number of membrane protein structures are known. Membrane proteins are challenging targets for structural biology, primarily due to the difficulty in producing and purifying milligram quantities of these proteins. We are evaluating different methods to produce and purify large numbers of prokaryotic membrane proteins for subsequent structural and functional analysis. Here, we present the comparative expression data for 37 target proteins, all of them secondary transporters, from the mesophilic organism Salmonella typhimurium and the two hyperthermophilic organisms Aquifex aeolicus and Pyrococcus furiosus in three different Escherichia coli expression vectors. In addition, we study the use of Lactococcus lactis as a host for integral membrane protein expression. Overall, 78% of the targets were successfully produced under at least one set of conditions. Analysis of these results allows us to assess the role of different variables in increasing "expression space" coverage for our set of targets. This analysis implies that to maximize the number of nonhomologous targets that are expressed, orthologous targets should be chosen and tested in two vectors with different types of promoters, using C-terminal tags. In addition, E. coli is shown to be a robust host for the expression of prokaryotic transporters, and is superior to L. lactis. These results therefore suggest appropriate strategies for high-throughput heterologous overproduction of membrane proteins.

  18. Cross-tissue Analysis of Gene and Protein Expression in Normal and Cancer Tissues.

    Science.gov (United States)

    Kosti, Idit; Jain, Nishant; Aran, Dvir; Butte, Atul J; Sirota, Marina

    2016-05-04

    The central dogma of molecular biology describes the translation of genetic information from mRNA to protein, but does not specify the quantitation or timing of this process across the genome. We have analyzed protein and gene expression in a diverse set of human tissues. To study concordance and discordance of gene and protein expression, we integrated mass spectrometry data from the Human Proteome Map project and RNA-Seq measurements from the Genotype-Tissue Expression project. We analyzed 16,561 genes and the corresponding proteins in 14 tissue types across nearly 200 samples. A comprehensive tissue- and gene-specific analysis revealed that across the 14 tissues, correlation between mRNA and protein expression was positive and ranged from 0.36 to 0.5. We also identified 1,012 genes whose RNA and protein expression was correlated across all the tissues and examined genes and proteins that were concordantly and discordantly expressed for each tissue of interest. We extended our analysis to look for genes and proteins that were differentially correlated in cancer compared to normal tissues, showing higher levels of correlation in normal tissues. Finally, we explored the implications of these findings in the context of biomarker and drug target discovery.

  19. The complex regulation of HIC (Human I-mfa domain containing protein) expression.

    Science.gov (United States)

    Reiss-Sklan, Ella; Levitzki, Alexander; Naveh-Many, Tally

    2009-07-07

    Human I-mfa domain containing protein (HIC) differentially regulates transcription from viral promoters. HIC affects the Wnt pathway, the JNK/SAPK pathway and the activity of positive transcription elongation factor-b (P-TEFb). Studies exploring HIC function in mammalian cells used ectopically expressed HIC due to undetected endogenous HIC protein. HIC mRNA contains exceptionally long 5' and 3' untranslated regions (UTRs) compared to the average length of mRNA UTRs. Here we show that HIC protein is subject to strict repression at multiple levels. The HIC mRNA UTRs reduce the expression of HIC or of a reporter protein: The HIC 3'-UTR decreases both HIC and reporter mRNA levels, whereas upstream open reading frames located in the 5'-UTR repress the translation of HIC or of the reporter protein. In addition, ectopically expressed HIC protein is degraded by the proteasome, with a half-life of approximately 1 h, suggesting that upon activation, HIC expression in cells may be transient. The strict regulation of HIC expression at the levels of mRNA stability, translation efficiency and protein stability suggests that expression of the HIC protein and its involvement in the various pathways is required only under specific cellular conditions.

  20. The complex regulation of HIC (Human I-mfa domain containing protein expression.

    Directory of Open Access Journals (Sweden)

    Ella Reiss-Sklan

    Full Text Available Human I-mfa domain containing protein (HIC differentially regulates transcription from viral promoters. HIC affects the Wnt pathway, the JNK/SAPK pathway and the activity of positive transcription elongation factor-b (P-TEFb. Studies exploring HIC function in mammalian cells used ectopically expressed HIC due to undetected endogenous HIC protein. HIC mRNA contains exceptionally long 5' and 3' untranslated regions (UTRs compared to the average length of mRNA UTRs. Here we show that HIC protein is subject to strict repression at multiple levels. The HIC mRNA UTRs reduce the expression of HIC or of a reporter protein: The HIC 3'-UTR decreases both HIC and reporter mRNA levels, whereas upstream open reading frames located in the 5'-UTR repress the translation of HIC or of the reporter protein. In addition, ectopically expressed HIC protein is degraded by the proteasome, with a half-life of approximately 1 h, suggesting that upon activation, HIC expression in cells may be transient. The strict regulation of HIC expression at the levels of mRNA stability, translation efficiency and protein stability suggests that expression of the HIC protein and its involvement in the various pathways is required only under specific cellular conditions.

  1. Immunogenicity of Newcastle disease virus vectors expressing Norwalk virus capsid protein in the presence or absence of VP2 protein.

    Science.gov (United States)

    Kim, Shin-Hee; Chen, Shun; Jiang, Xi; Green, Kim Y; Samal, Siba K

    2015-10-01

    Noroviruses are the most common cause of acute gastroenteritis in humans. Development of an effective vaccine is required for reducing their outbreaks. In order to develop a GI norovirus vaccine, Newcastle disease virus vectors, rLaSota and modified rBC, were used to express VP1 protein of Norwalk virus. Co-expression of VP1 and VP2 proteins by Newcastle disease virus vectors resulted in enhanced expression of Norwalk virus VP1 protein and self-assembly of VP1 protein into virus-like particles. Furthermore, the Norwalk virus-specific IgG response induced in mice by Newcastle disease virus vectors was similar to that induced by baculovirus-expressed virus-like particles in mice. However, the modified rBC vector in the presence of VP2 protein induced significantly higher levels of cellular and mucosal immune responses than those induced by baculovirus-expressed VLPs. These results indicate that Newcastle disease virus has great potential for developing a live Norwalk virus vaccine by inducing humoral, cellular and mucosal immune responses in humans.

  2. Shift in S-layer protein expression responsible for antigenic variation in Campylobacter fetus.

    OpenAIRE

    Wang, E; Garcia, M M; Blake, M. S.; Pei, Z.; Blaser, M J

    1993-01-01

    Campylobacter fetus strains possess regular paracrystalline surface layers (S-layers) composed of high-molecular-weight proteins and can change the size and crystalline structure of the predominant protein expressed. Polyclonal antisera demonstrate antigenic cross-reactivity among these proteins but suggest differences in epitopes. Monoclonal antibodies to the 97-kDa S-layer protein of Campylobacter fetus subsp. fetus strain 82-40LP showed three different reactivities. Monoclonal antibody 1D1...

  3. Strategies for production of active eukaryotic proteins in bacterial expression system

    Institute of Scientific and Technical Information of China (English)

    Orawan Khow; Sunutcha Suntrarachun

    2012-01-01

    Bacteria have long been the favorite expression system for recombinant protein production. However, the flaw of the system is that insoluble and inactive proteins are co-produced due to codon bias, protein folding, phosphorylation, glycosylation, mRNA stability and promoter strength. Factors are cited and the methods to convert to soluble and active proteins are described, for example a tight control of Escherichia coli milieu, refolding from inclusion body and through fusion technology.

  4. Evidence of prognostic relevant expression profiles of heat-shock proteins and glucose-regulated proteins in oesophageal adenocarcinomas.

    Directory of Open Access Journals (Sweden)

    Julia Slotta-Huspenina

    Full Text Available A high percentage of oesophageal adenocarcinomas show an aggressive clinical behaviour with a significant resistance to chemotherapy. Heat-shock proteins (HSPs and glucose-regulated proteins (GRPs are molecular chaperones that play an important role in tumour biology. Recently, novel therapeutic approaches targeting HSP90/GRP94 have been introduced for treating cancer. We performed a comprehensive investigation of HSP and GRP expression including HSP27, phosphorylated (p-HSP27((Ser15, p-HSP27((Ser78, p-HSP27((Ser82, HSP60, HSP70, HSP90, GRP78 and GRP94 in 92 primary resected oesophageal adenocarcinomas by using reverse phase protein arrays (RPPA, immunohistochemistry (IHC and real-time quantitative RT-PCR (qPCR. Results were correlated with pathologic features and survival. HSP/GRP protein and mRNA expression was detected in all tumours at various levels. Unsupervised hierarchical clustering showed two distinct groups of tumours with specific protein expression patterns: The hallmark of the first group was a high expression of p-HSP27((Ser15, Ser78, Ser82 and low expression of GRP78, GRP94 and HSP60. The second group showed the inverse pattern with low p-HSP27 and high GRP78, GRP94 and HSP60 expression. The clinical outcome for patients from the first group was significantly improved compared to patients from the second group, both in univariate analysis (p = 0.015 and multivariate analysis (p = 0.029. Interestingly, these two groups could not be distinguished by immunohistochemistry or qPCR analysis. In summary, two distinct and prognostic relevant HSP/GRP protein expression patterns in adenocarcinomas of the oesophagus were detected by RPPA. Our approach may be helpful for identifying candidates for specific HSP/GRP-targeted therapies.

  5. Evidence of prognostic relevant expression profiles of heat-shock proteins and glucose-regulated proteins in oesophageal adenocarcinomas.

    Science.gov (United States)

    Slotta-Huspenina, Julia; Berg, Daniela; Bauer, Karina; Wolff, Claudia; Malinowsky, Katharina; Bauer, Lukas; Drecoll, Enken; Bettstetter, Marcus; Feith, Marcus; Walch, Axel; Höfler, Heinz; Becker, Karl-Friedrich; Langer, Rupert

    2012-01-01

    A high percentage of oesophageal adenocarcinomas show an aggressive clinical behaviour with a significant resistance to chemotherapy. Heat-shock proteins (HSPs) and glucose-regulated proteins (GRPs) are molecular chaperones that play an important role in tumour biology. Recently, novel therapeutic approaches targeting HSP90/GRP94 have been introduced for treating cancer. We performed a comprehensive investigation of HSP and GRP expression including HSP27, phosphorylated (p)-HSP27((Ser15)), p-HSP27((Ser78)), p-HSP27((Ser82)), HSP60, HSP70, HSP90, GRP78 and GRP94 in 92 primary resected oesophageal adenocarcinomas by using reverse phase protein arrays (RPPA), immunohistochemistry (IHC) and real-time quantitative RT-PCR (qPCR). Results were correlated with pathologic features and survival. HSP/GRP protein and mRNA expression was detected in all tumours at various levels. Unsupervised hierarchical clustering showed two distinct groups of tumours with specific protein expression patterns: The hallmark of the first group was a high expression of p-HSP27((Ser15, Ser78, Ser82)) and low expression of GRP78, GRP94 and HSP60. The second group showed the inverse pattern with low p-HSP27 and high GRP78, GRP94 and HSP60 expression. The clinical outcome for patients from the first group was significantly improved compared to patients from the second group, both in univariate analysis (p = 0.015) and multivariate analysis (p = 0.029). Interestingly, these two groups could not be distinguished by immunohistochemistry or qPCR analysis. In summary, two distinct and prognostic relevant HSP/GRP protein expression patterns in adenocarcinomas of the oesophagus were detected by RPPA. Our approach may be helpful for identifying candidates for specific HSP/GRP-targeted therapies.

  6. miR-24 and miR-205 expression is dependent on HPV onco-protein expression in keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    McKenna, Declan J., E-mail: dj.mckenna@ulster.ac.uk [Biomedical Sciences Research Institute, University of Ulster, Coleraine, Co. Derry BT52 1SA (United Kingdom); Centre for Cancer Research and Cell Biology, School of Medicine, Dentistry and Biomedical Science, Queen' s University Belfast, Belfast BT9 7BL (United Kingdom); Patel, Daksha, E-mail: d.patel@qub.ac.uk [Centre for Cancer Research and Cell Biology, School of Medicine, Dentistry and Biomedical Science, Queen' s University Belfast, Belfast BT9 7BL (United Kingdom); McCance, Dennis J., E-mail: d.mccance@qub.ac.uk [Centre for Cancer Research and Cell Biology, School of Medicine, Dentistry and Biomedical Science, Queen' s University Belfast, Belfast BT9 7BL (United Kingdom)

    2014-01-05

    A screen of microRNA (miRNA) expression following differentiation in human foreskin keratinocytes (HFKs) identified changes in several miRNAs, including miR-24 and miR-205. We investigated how expression of Human Papilloma Virus Type-16 (HPV16) onco-proteins E6 and E7 affected expression of miR-24 and miR-205 during proliferation and differentiation of HFKs. We show that the induction of both miR-24 and miR-205 observed during differentiation of HFKs is lost in HFKs expressing E6 and E7. We demonstrate that the effect on miR-205 is due to E7 activity, as miR-205 expression is dependent on pRb expression. Finally, we provide evidence that miR-24 effects in the cell may be due to targeting of cyclin dependent kinase inhibitor p27. In summary, these results indicate that expression of both miR-24 and miR-205 are impacted by E6 and/or E7 expression, which may be one mechanism by which HPV onco-proteins can disrupt the balance between proliferation and differentiation in keratinocytes. - Highlights: • miR-24 and miR-205 are induced during keratinocyte differentiation. • This induction is lost in keratinocytes expressing HPV onco-proteins E6 and E7. • miR-205 is dependent upon pRb expression. • miR-24 targets p27 in cycling keratinocytes.

  7. [Expression and immunogenicity of equine infectious anemia virus membrane protein GP90].

    Science.gov (United States)

    Dai, Chuan-bin; Xiao, Yao; Lu, Hong; Shen, Rong-xian; Shao, Yi-ming

    2003-03-01

    Membrane protein GP90 of China equine infectious anemia virus (EIAV) vaccine strain (DLV) and its parental wild type LN strain were expressed with Bac-to-Bac baculovirus expression system and BALB/c mice were inoculated with purified protein, thereby to explore the availability of protein for differential diagnosis and potential for preparing genetically engineered vaccine. The authors infected donkey PBMC culture with China EIAV vaccine strain (DLV) and its parental wild type LN strain, extracted its proviral DNA as template, amplified the GP90 of DLV and LN, respectively, and expressed with Bac-to-Bac baculovirus expression system. The sf9 insect cells were infected with the recombinant baculovirus and the expressed proteins were purified by IMAC. BALB/c mice were inoculated with purified protein. The specific binding Abs generated in the immunized mice were determined by ELISA method. The neutralizing assay was set up to determine the neutralizing capability of the antigens generated in immunized animals. The recombinant virus expressing viral antigens was determined by Western blot. The expressed proteins were purified by IMAC resulting in the protein purity of 87%(DLV) and 82%(LN), respectively. The antibody titer of the groups with and without adjuvant was 1 600 and 800, respectively. Serial 2 fold dilutions of the immunized mice sera were reacted with 100 TCID50 of EIAV. The end point of immunization assay was to protect 50% cells form CPE caused by EIAV in donkey skin cells. The neutralizing antibody titer was in the range 40 to 80 from animal immunized with and without adjuvant. Membrane proteins of EIAV vaccine strain and wild type strain were successfully expressed in eukaryotic cell expression system according to the scheduled plan. The proteins showed strong immunogenicity and could activate animals to produce anti-EIAV specific antibody including neutralizing antibody to EIAV.

  8. Expression of the SET protein in testes of mice at different developmental stages

    Institute of Scientific and Technical Information of China (English)

    Xiao-Nan Dai; Shan Liu; Li Shao; Chao Gao; Li Gao; Jia-Yin Liu; Yu-Gui Cui

    2014-01-01

    SET is a multifunctional protein involved in regulating many biological processes of the cell cycle. It is also a regulator of steroidogenesis in the ovary. However, the expression of SET protein in testis, and its function, still remains ambiguous. In this study, we observed the expression of SET in the testes of mice at different developmental stages, and have discussed its potential function in regulating spermatogenesis and androgen production. Forty‑eight male mice at different developmental stages(1week old as the infancy group; 4weeks old as the prepubertal group; 12weeks old as the adult group; over12months old as the ageing group) were used. Cellular location of SET protein in the testes was observed by immuno‑histochemistry. Expression levels of Set mRNA and SET protein were analyzed by quantitative polymerase chain reaction and Western blotting. SET protein was expressed in spermatogonial cells and spermatocytes; the highest level was mainly in haploid and tetraploid cells of the prepubertal and adult groups, and Leydig cells of the adult and ageing groups. There was a low expression in Sertoli cells. Expression of Set mRNA in the prepubertal group was signiifcantly higher than that in the adult group(P<0.05), while expression of SET protein was at the highest level in the adult group(P<0.05).SET protein is mainly expressed in spermatogonial cells and spermatocytes, and poorly expressed in Sertoli cells, suggesting that it is involved in spermatogenesis. Expression of SET protein in Leydig cells suggests a possible role in steroidogenesis.

  9. Downregulation of ATM Gene and Protein Expression in Canine Mammary Tumors.

    Science.gov (United States)

    Raposo-Ferreira, T M M; Bueno, R C; Terra, E M; Avante, M L; Tinucci-Costa, M; Carvalho, M; Cassali, G D; Linde, S D; Rogatto, S R; Laufer-Amorim, R

    2016-11-01

    The ataxia telangiectasia mutated (ATM) gene encodes a protein associated with DNA damage repair and maintenance of genomic integrity. In women, ATM transcript and protein downregulation have been reported in sporadic breast carcinomas, and the absence of ATM protein expression has been associated with poor prognosis. The aim of this study was to evaluate ATM gene and protein expression in canine mammary tumors and their association with clinical outcome. ATM gene and protein expression was evaluated by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry, respectively, in normal mammary gland samples (n = 10), benign mammary tumors (n = 11), nonmetastatic mammary carcinomas (n = 19), and metastatic mammary carcinomas (n = 11). Lower ATM transcript levels were detected in benign mammary tumors and carcinomas compared with normal mammary glands (P = .011). Similarly, lower ATM protein expression was observed in benign tumors (P = .0003), nonmetastatic mammary carcinomas (P ATM gene or protein levels were detected among benign tumors and nonmetastatic and metastatic mammary carcinomas (P > .05). The levels of ATM gene or protein expression were not significantly associated with clinical and pathological features or with survival. Similar to human breast cancer, the data in this study suggest that ATM gene and protein downregulation is involved in canine mammary gland tumorigenesis.

  10. Clinicopathological significance of p53 and mdm2 protein expression in human pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Ming Dong; Gang Ma; Wei Tu; Ke-Jian Guo; Yu-Lin Tian; Yu-Ting Dong

    2005-01-01

    AIM: To study the clinicopathological significance of p53 and mdm2 protein expression in human pancreatic cancer. METHODS: To investigate the expression of p53 and mdm2 in pancreatic cancer by immunohistochemistry, and the relationships between the p53 and mdm2 protein expression and clinicopathological parameters in pancreatic cancer.RESULTS: The positive expression of p53 protein was found in 40 of 59 patients (67.8%) and that of mdm2 protein in 17 of 59 patients (28.8%). No obvious relationships were found between p53 as well as mdm2 expression and sex, tumor site, TNM staging and histological differentiation. p53 expression was increased in patients younger than 65 years old, while mdm2 had no relationship with age. The survival time of the patients with the positive expression of p53 and mdm2 proteins was obviously shorter than the other groups. CONCLUSION: Both p53 and mdm2 presented relatively high expression in human pancreatic cancer. The overexpression of p53 and mdm2 might reflect the malignant proliferation of pancreatic cancer and their co-expression might be helpful to evaluate the prognosis of the patients with pancreatic cancer.

  11. Molecular Cloning and Prokaryotic Expression of Non-Structural Protein NS1 Gene of Porcine Parvovirus

    Institute of Scientific and Technical Information of China (English)

    WU Dan; TONG Guang-zhi; QIU Hua-ji; XUE Qiang; ZHOU Yan-jun; LI Jing-peng

    2003-01-01

    Porcine parvovirus (PPV) is one of the major agents causing swine reproductive failure. NS1protein is a non-structural protein of PPV and can be used as a reagent for differentiation of vaccinated ani-mals and infected ones. In present study, a recombinant plasmid pET28a/NS1 was constructed by cloning thecoding sequence for NS1 of PPV into pET28a, a bacterial expression vector. The NS1 protein was expressed inE. coli BL21 (DE3) after induced by IPTG and the recombinant fusion protein was purified with affinity chro-matography. Expression amount of NS1 protein was improved by optimizing the inducing parameters. The re-combinant NS1 protein is reactive to PPV positive sera in Western blot and ELISA test and therefore can beapplicable in differential diagnosis of PPV infections.

  12. Expression of mRNA and protein-protein interaction of the antiviral endoribonuclease RNase L in mouse spleen.

    Science.gov (United States)

    Gupta, Ankush; Rath, Pramod C

    2014-08-01

    The interferon-inducible, 2',5'-oligoadenylate (2-5A)-dependent endoribonuclease, RNase L is a unique antiviral RNA-degrading enzyme involved in RNA-metabolism, translational regulation, stress-response besides its anticancer/tumor-suppressor and antibacterial functions. RNase L represents complex cellular RNA-regulations in mammalian cells but diverse functions of RNase L are not completely explained by its 2-5A-regulated endoribonuclease activity. We hypothesized that RNase L has housekeeping function(s) through interaction with cellular proteins. We investigated RNase L mRNA expression in mouse tissues by RT-PCR and its protein-protein interaction in spleen by GST-pulldown and immunoprecipitation assays followed by proteomic analysis. RNase L mRNA is constitutively and differentially expressed in nine different mouse tissues, its level is maximum in immunological tissues (spleen, thymus and lungs), moderate in reproductive tissues (testis and prostate) and low in metabolic tissues (kidney, brain, liver and heart). Cellular proteins from mouse spleen [fibronectin precursor, β-actin, troponin I, myosin heavy chain 9 (non-muscle), growth-arrest specific protein 11, clathrin light chain B, a putative uncharacterized protein (Ricken cDNA 8030451F13) isoform (CRA_d) and alanyl tRNA synthetase] were identified as cellular RNase L-interacting proteins. Thus our results suggest for more general cellular functions of RNase L through protein-protein interactions in the spleen for immune response in mammals.

  13. Dual-function vector for protein expression in both mammalian cells and Xenopus laevis oocytes

    DEFF Research Database (Denmark)

    Jespersen, Thomas; Grunnet, M; Angelo, K;

    2002-01-01

    will often engage both oocytes and mammalian cells. Efficient expression of a protein in both systems have thus far only been possible by subcloning the cDNA into two different vectors because several different molecular requirements should be fulfilled to obtain a high protein level in both mammalian cells...... and oocytes. To address this problem, we have constructed a plasmid vector, pXOOM, that can function as a template for expression in both oocytes and mammalian cells. By including all the necessary RNA stability elements for oocyte expression in a standard mammalian expression vector, we have obtained a dual......-function vector capable of supporting protein production in both Xenopus oocytes and CHO-K1 cells at an expression level equivalent to the levels obtained with vectors optimized for either oocyte or mammalian expression. Our functional studies have been performed with hERGI, KCNQ4, and Kv1.3 potassium channels....

  14. Classification, expression pattern and comparative analysis of sugarcane expressed sequences tags (ESTs encoding glycine-rich proteins (GRPs

    Directory of Open Access Journals (Sweden)

    Fusaro Adriana

    2001-01-01

    Full Text Available Since the isolation of the first glycine-rich proteins (GRPs in plants a wealth of new GRPs have been identified. The highly specific but diverse expression pattern of grp genes, taken together with the distinct sub-cellular localization of some GRP groups, clearly indicate that these proteins are involved in several independent physiological processes. Notwithstanding the absence of a clear definition of the role of GRPs in plant cells, studies conducted with these proteins have provided new and interesting insights into the molecular biology and cell biology of plants. Complexly regulated promoters and distinct mechanisms for the regulation of gene expression have been demonstrated and new protein targeting pathways, as well as the exportation of GRPs from different cell types have been discovered. These data show that GRPs can be useful as markers and/or models to understand distinct aspects of plant biology. In this paper, the structural and functional features of these proteins in sugarcane (Saccharum officinarum L. are summarized. Since this is the first description of GRPs in sugarcane, special emphasis has been given to the expression pattern of these GRP genes by studying their abundance and prevalence in the different cDNA-libraries of the Sugarcane Expressed Sequence Tag (SUCEST project . The comparison of sugarcane GRPs with GRPs from other species is also discussed.

  15. Identification of differentially expressed proteins in response to Pb ...

    African Journals Online (AJOL)

    use

    in many forms in natural sources throughout the world. According to the environmental protection ... has been attached to the problems of Pb pollution with ..... structure of proteins and/or increased degradation, thus ..... Plant Soil, 200: 241-250.

  16. Expression of melanin and insecticidal protein from Rhodotorula ...

    African Journals Online (AJOL)

    SERVER

    2006-02-16

    Feb 16, 2006 ... Key words: Rhodotorula glutinis, Escherichia coli, Melanin, Insecticidal Protein. INTRODUCTION ... proteinaceous crystals toxic to different insect larvae (Bulla ..... Gulex univitattus, Aedes aegypti and Culex pipens. Mosq.

  17. Statistical approaches to maximize recombinant protein expression in Escherichia coli: a general review.

    Science.gov (United States)

    Papaneophytou, Christos P; Kontopidis, George

    2014-02-01

    The supply of many valuable proteins that have potential clinical or industrial use is often limited by their low natural availability. With the modern advances in genomics, proteomics and bioinformatics, the number of proteins being produced using recombinant techniques is exponentially increasing and seems to guarantee an unlimited supply of recombinant proteins. The demand of recombinant proteins has increased as more applications in several fields become a commercial reality. Escherichia coli (E. coli) is the most widely used expression system for the production of recombinant proteins for structural and functional studies. However, producing soluble proteins in E. coli is still a major bottleneck for structural biology projects. One of the most challenging steps in any structural biology project is predicting which protein or protein fragment will express solubly and purify for crystallographic studies. The production of soluble and active proteins is influenced by several factors including expression host, fusion tag, induction temperature and time. Statistical designed experiments are gaining success in the production of recombinant protein because they provide information on variable interactions that escape the "one-factor-at-a-time" method. Here, we review the most important factors affecting the production of recombinant proteins in a soluble form. Moreover, we provide information about how the statistical design experiments can increase protein yield and purity as well as find conditions for crystal growth. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Protein Kinase CK2 Expression Predicts Relapse Survival in ERα Dependent Breast Cancer, and Modulates ERα Expression in Vitro

    OpenAIRE

    2015-01-01

    The heterotetrameric protein kinase CK2 has been associated with oncogenic transformation, and our previous studies have shown that it may affect estrogenic signaling. Here, we investigate the role of the protein kinase CK2 in regulating ERα (estrogen receptor α) signaling in breast cancer. We determined the correlation of CK2α expression with relapse free breast cancer patient survival utilizing Kaplan Meier Plotter (kmplot.com/analysis/) to mine breast cancer microarrays repositories. Patie...

  19. Isatin decreases Bax protein expression in the substantia nigra of a mouse model of Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    Jiguo Zhang; Fang Zhang; Yanlong Qiu; Wang Yue

    2011-01-01

    The present study observed the action of 1H-indole-2, 3-dione (isatin) on Bax protein expression in the substantia nigra of a Parkinson's disease animal model. Parkinson's disease-like behaviors were induced in C57BL/6J mice treated with 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). Bax protein expression was significantly reduced in isatin (100, 200 mg/kg)-pretreated mice. Results demonstrate that isatin plays a neuroprotective role in mice treated with MPTP by down-regulating Bax protein expression.

  20. Tuning protein expression using synonymous codon libraries targeted to the 5' mRNA coding region

    DEFF Research Database (Denmark)

    Goltermann, Lise; Borch Jensen, Martin; Bentin, Thomas

    2011-01-01

    In bacteria, the 5' mRNA coding region plays an important role in determining translation output. Here, we report synthetic sequences that when placed in the 5'-mRNA coding region, leading to recombinant proteins containing short N-terminal extensions, virtually abolish, enhance or produce...... intermediate expression levels of green fluorescent protein in Escherichia coli. At least in one case, no apparent effect on protein stability was observed, pointing to RNA level effects as the principal reason for the observed expression differences. Targeting a synonymous codon library to the 5' coding...... and hence is important to recombinant and, most certainly, endogenous gene expression....

  1. Construction of eukaryotic expression vector encoding ATP synthase lipid-binding protein-like protein gene of Sj and its expression in HeLa cells

    Institute of Scientific and Technical Information of China (English)

    Ouyang Danming; Hu Yongxuan; Li Mulan; Zeng Xiaojun; He Zhixiong; Yuan Caijia

    2008-01-01

    Objective: To clone and construct the recombinant plasmid containing ATP synthase lipid-binding protein-like protein gene of Schistosoma japonicum,(SjAslp) and transfer it into mammalian cells to express the objective protein. Methods: By polymerase chain reaction (PCR) technique, SjAslp was amplified from the constructed recombinant plasmid pBCSK+/SjAslp, and inserted into cloning vector pUCm-T. Then, SjAslp was subcloned into an eukaryotic expression vector pcDNA3.1(+). After identifying it by PCR, restrictive enzymes digestion and DNA sequencing, the recombinant plasmid was transfected into HeLa cells using electroporation, and the expression of the recombinant protein was analyzed by immunocytochemical assay. Resnlts: The specific gene fragment of 558 bp was successfully amplified. The DNA vaccine of SjAslp was successfully constructed. Immunocytochemical assay showed that SjAslp was expressed in the cytoplasm of HeLa cells. Conclusion: SjAslp gene can be expressed in eukaryotic system, which lays the foundation for development of the SjAslp DNA vaccine against schitosomiasis.

  2. Molecular characterization of Gla-rich protein (GRP) gene expression and function

    OpenAIRE

    Fazenda, Cindy Vitória

    2014-01-01

    Gla-rich protein (GRP) is a vitamin K-dependent protein related to bone and cartilage recently described. This protein is characterized by a large number of Gla (γ-carboxyglutamic acid) residues being the protein with the highest Gla content of any known protein. It was found in a widely variety of tissues but highest levels was found in skeletal and cartilaginous tissues. This small secreted protein was also expressed and accumulated in soft tissues and it was clearly associated with calcifi...

  3. A second rhodopsin-like protein in Cyanophora paradoxa: gene sequence and protein expression in a cell-free system.

    Science.gov (United States)

    Frassanito, Anna Maria; Barsanti, Laura; Passarelli, Vincenzo; Evangelista, Valtere; Gualtieri, Paolo

    2013-08-05

    Here we report the identification and expression of a second rhodopsin-like protein in the alga Cyanophora paradoxa (Glaucophyta), named Cyanophopsin_2. This new protein was identified due to a serendipity event, since the RACE reaction performed to complete the sequence of Cyanophopsin_1, (the first rhodopsin-like protein of C. paradoxa identified in 2009 by our group), amplified a 619 bp sequence corresponding to a portion of a new gene of the same protein family. The full sequence consists of 1175 bp consisting of 849 bp coding DNA sequence and 4 introns of 326 bp. The protein is characterized by an N-terminal region of 47 amino acids, followed by a region with 7 α-helices of 213 amino acids and a C-terminal region of 22 amino acids. This protein showed high identity with Cyanophopsin_1 and other rhodopsin-like proteins of Archea, Bacteria, Fungi and Algae. Cyanophosin_2 (CpR2) was expressed in a cell-free expression system, and characterized by means of absorption spectroscopy.

  4. Leptin modulated changes in adipose tissue protein expression in ob/ob mice.

    Science.gov (United States)

    Zhang, Wei; Ambati, Suresh; Della-Fera, Mary Anne; Choi, Yang-Ho; Baile, Clifton A; Andacht, Tracy M

    2011-02-01

    Comparative proteomic analyses were performed in adipose tissue of leptin-deficient ob/ob mice treated with leptin or control buffer in order to identify the protein expression changes as the potential targets of leptin. Mice were treated with either phosphate-buffered saline (control) or 10 µg/day leptin for 14 days via subcutaneous osmotic minipumps. Total protein from white adipose tissue was extracted and labeled with different fluorescent cyanine dyes for analysis by two-dimensional difference gel electrophoresis (DIGE). Spots that were differentially expressed and appeared to have sufficient material for mass spectrometry analysis were picked and digested with trypsin and subjected to MALDI-TOF MS for protein identification. Twelve functional protein groups were found differentially expressed in adipose tissue of leptin-treated vs. control ob/ob mice, including molecular chaperones and redox proteins such as calreticulin (CALR), protein disulfide isomerase-associated 3 (PDIA3), prohibitin (PHB), and peroxiredoxin-6 (PRDX6); cytoskeleton proteins such as β actin, desmin, and α-tubulin; and some other proteins. The mRNA levels of CALR, PDIA3, and PHB were measured by real-time reverse transcription-PCR and found to be upregulated (P leptin's effects on lipid metabolism and apoptosis may be mediated in part by alterations in expression of molecular chaperones and redox proteins for regulating endoplasmic reticulum stress and cytoskeleton proteins for regulating mitochondrial morphology.

  5. Proteomic analysis of differentially expressed proteins in Fenneropenaeus chinensis hemocytes upon white spot syndrome virus infection.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available To elucidate molecular responses of shrimp hemocytes to white spot syndrome virus (WSSV infection, two-dimensional gel electrophoresis was applied to investigate differentially expressed proteins in hemocytes of Chinese shrimp (Fenneropenaeus chinensis at 24 h post infection (hpi. Approximately 580 protein spots were detected in hemocytes of healthy and WSSV-infected shrimps. Quantitative intensity analysis revealed 26 protein spots were significantly up-regulated, and 19 spots were significantly down-regulated. By mass spectrometry, small ubiquitin-like modifier (SUMO 1, cytosolic MnSOD, triosephosphate isomerase, tubulin alpha-1 chain, microtubule-actin cross-linking factor 1, nuclear receptor E75 pr