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Untargeted metabolomic analysis of human serum samples associated with different levels of red meat consumption: A possible indicator of type 2 diabetes? Food Chem 2017; 221:214-221. [DOI: 10.1016/j.foodchem.2016.10.056] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 09/26/2016] [Accepted: 10/12/2016] [Indexed: 11/19/2022]
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2
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Wingens M, Gätgens J, Schmidt A, Albaum SP, Büntemeyer H, Noll T, Hoffrogge R. 2D-DIGE screening of high-productive CHO cells under glucose limitation--basic changes in the proteome equipment and hints for epigenetic effects. J Biotechnol 2015; 201:86-97. [PMID: 25612871 DOI: 10.1016/j.jbiotec.2015.01.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 12/23/2014] [Accepted: 01/09/2015] [Indexed: 01/21/2023]
Abstract
CHO derivates (Chinese hamster ovary) belong to the most important mammalian cells for industrial recombinant protein production. Many efforts have been made to improve productivity and stability of CHO cells in bioreactor processes. Here, we followed up one barely understood phenomenon observed with process optimizations: a significantly increased cell-specific productivity in late phases of glucose-limited perfusion cultivations, when glucose (and lactate) reserves are exhausted. Our aim was to elucidate the cellular activities connected to the metabolic shift from glucose surplus to glucose limitation phase. With 2D-DIGE, we compared three stages in a perfusion culture of CHO cells: the initial growth with high glucose concentration and low lactate production, the second phase with glucose going to limitation and high lactate level, and finally the state of glucose limitation and also low lactate concentration but increased cell-specific productivity. With our proteomic approach we were able to demonstrate consequences of glucose limitation for the protein expression machinery which also could play a role for a higher recombinant protein production. Most interestingly, we detected epigenetic effects on the level of proteins involved in histone modification (HDAC1/-2, SET, RBBP7, DDX5). Together with shifts in the protein inventory of energy metabolism, cytoskeleton and protein expression, a picture emerges of basic changes in the cellular equipment under long-term glucose limitation of CHO cells.
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Affiliation(s)
- Marc Wingens
- Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany
| | - Jochem Gätgens
- IBG-1: Biotechnology; Bioprocesses and Bioanalytics, Research Center Jülich, Germany
| | - Anica Schmidt
- Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany
| | - Stefan P Albaum
- Bioinformatics Resource Facility, Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Heino Büntemeyer
- Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany
| | - Thomas Noll
- Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany
| | - Raimund Hoffrogge
- Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany.
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Hou Q, Tan HT, Lim KH, Lim TK, Khoo A, Tan IBH, Yeoh KG, Chung MCM. Identification and functional validation of caldesmon as a potential gastric cancer metastasis-associated protein. J Proteome Res 2013; 12:980-90. [PMID: 23265641 DOI: 10.1021/pr3010259] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In this study, we aim to identify biomarkers for gastric cancer metastasis using a quantitative proteomics approach. The proteins extracted from a panel of 4 gastric cancer cell lines, two derived from primary cancer (AGS, FU97) and two from lymph node metastasis (AZ521, MKN7), were labeled with iTRAQ (8-plex) reagents and analyzed by 2D-LC-MALDI-TOF/TOF MS. In total, 641 proteins were identified with at least a 95% confidence. Using cutoff values of >1.5 and <0.67, 19 proteins were found to be up-regulated and 34 were down-regulated in the metastatic versus primary gastric cancer cell lines respectively. Several of these dysregulated proteins, including caldesmon, were verified using Western blotting. It was found that caldesmon expression was decreased in the two metastasis-derived cell lines, and this was confirmed by further analysis of 7 gastric cancer cell lines. Furthermore, immunohistochemical staining of 9 pairs of primary gastric cancer and the matched lymph node metastasis tissue also corroborated this observation. Finally, knockdown of caldesmon using siRNA in AGS and FU97 gastric cancer cells resulted in an increase in cell migration and invasion, while the overexpression of caldesmon in AZ521 cells led to a decrease in cell migration and invasion. This study has thus established the potential role of caldesmon in gastric cancer metastasis, and further functional studies are underway to delineate the underlying mechanism of action of this protein.
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Affiliation(s)
- Qian Hou
- Department of Biochemistry, National University of Singapore, 8 Medical Drive, Singapore 117597
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4
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Derijks-Engwegen JY, Cats A, Smits ME, Schellens JH, Beijnen JH. Improving colorectal cancer management: the potential of proteomics. Biomark Med 2012; 2:253-89. [PMID: 20477414 DOI: 10.2217/17520363.2.3.253] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Colorectal cancer (CRC) is the third most common cancer worldwide. Successful treatment is heavily dependent on tumor stage at the time of detection, but unfortunately CRC is often only detected in advanced stages. New biomarkers in the form of genes or proteins that can be used for diagnosis, prognostication, follow-up, and treatment selection and monitoring could be of great benefit for the management of CRC. Furthermore, proteins could prove valuable new targets for therapy. Therefore, clinical proteomics has gained a lot of scientific interest in this regard. To get an overall insight into the extent to which this research has contributed to a better management of CRC, we give a comprehensive overview of the results of proteomics research on CRC, focusing on expression proteomics, in other words, protein profiling studies. Furthermore, we evaluate the potential of the discriminating proteins identified in this research for clinical use as biomarkers for (early) diagnosis, prognosis and follow-up of CRC or as targets for new therapeutic regimens.
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Hu L, Paul Fawcett J, Gu J. Protein target discovery of drug and its reactive intermediate metabolite by using proteomic strategy. Acta Pharm Sin B 2012. [DOI: 10.1016/j.apsb.2012.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Tan HT, Wu W, Ng YZ, Zhang X, Yan B, Ong CW, Tan S, Salto-Tellez M, Hooi SC, Chung MCM. Proteomic analysis of colorectal cancer metastasis: stathmin-1 revealed as a player in cancer cell migration and prognostic marker. J Proteome Res 2012; 11:1433-45. [PMID: 22181002 DOI: 10.1021/pr2010956] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metastasis accounts largely for the high mortality rate of colorectal cancer (CRC) patients. In this study, we performed comparative proteome analysis of primary CRC cell lines HCT-116 and its metastatic derivative E1 using 2-D DIGE. We identified 74 differentially expressed proteins, many of which function in transcription, translation, angiogenesis signal transduction, or cytoskeletal remodeling pathways, which are indispensable cellular processes involved in the metastatic cascade. Among these proteins, stathmin-1 (STMN1) was found to be highly up-regulated in E1 as compared to HCT-116 and was thus selected for further functional studies. Our results showed that perturbations in STMN1 levels resulted in significant changes in cell migration, invasion, adhesion, and colony formation. We further showed that the differential expression of STMN1 correlated with the cells' metastatic potential in other paradigms of CRC models. Using immunohistochemistry, we also showed that STMN1 was highly expressed in colorectal primary tumors and metastatic tissues as compared to the adjacent normal colorectal tissues. Furthermore, we also showed via tissue microarray analyses of 324 CRC tissues and Kaplan-Meier survival plot that CRC patients with higher expression of STMN1 have poorer prognosis.
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Affiliation(s)
- Hwee Tong Tan
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , 8 Medical Drive, Singapore 117597, Singapore
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7
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Krasnov GS, Khankin SL, Bukurova YA, Zatsepina OG, Oparina NY, Garbuz DG, Ershov AN, Mashkova TD, Karpov VL, Beresten SF. Proteomic expression analysis of human colorectal cancer: Identification of soluble overexpressed proteins. Mol Biol 2009. [DOI: 10.1134/s0026893309040050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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8
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Aki T, Yanagisawa S. Application of Rice Nuclear Proteome Analysis to the Identification of Evolutionarily Conserved and Glucose-Responsive Nuclear Proteins. J Proteome Res 2009; 8:3912-24. [DOI: 10.1021/pr900187e] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Toshihiko Aki
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan, and Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
| | - Shuichi Yanagisawa
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan, and Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
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Fung KYC, Lewanowitsch T, Henderson ST, Priebe I, Hoffmann P, McColl SR, Lockett T, Head R, Cosgrove LJ. Proteomic analysis of butyrate effects and loss of butyrate sensitivity in HT29 colorectal cancer cells. J Proteome Res 2009; 8:1220-7. [PMID: 19195990 DOI: 10.1021/pr8009929] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Butyrate, a fermentation product of the large bowel microflora, is potentially protective against the development of colorectal cancer. In vitro, butyrate has been shown to induce apoptosis and inhibit proliferation in numerous cancer cell lines, including colorectal cancer. Although these tumor suppressing properties of butyrate are well-documented in experimental systems, the mechanisms underlying the induction of these effects are not fully understood. Understanding these mechanisms in cancer cells, as well as the pathways involved in a cell's ability to overcome them and progress toward malignancy, is vital to determine therapeutic approaches for disease management. We have developed a colorectal cancer cell line (HT29-BR) that is less responsive to the apoptotic effects of butyrate through sustained exposure of HT29 cells to 5 mM butyrate and have used proteomics to investigate the mechanisms involved in the development of butyrate insensitivity. Proteomic analysis identified a number of cellular processes in HT29 and HT29-BR cells influenced by butyrate including remodeling of the actin cytoskeleton, inhibition of protein biosynthesis and dysregulation of the cell stress response. We describe novel roles for butyrate in the induction of its tumor suppressing effects and outline potential cellular pathways involved in the development of butyrate insensitivity in the HT29-BR cell population.
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Affiliation(s)
- Kim Y C Fung
- CSIRO Preventative Health Flagship, Australia, CSIRO, Human Nutrition, Adelaide, Australia, CSIRO, Division of Molecular and Health Technologies, Adelaide, Australia
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Minden JS, Dowd SR, Meyer HE, Stühler K. Difference gel electrophoresis. Electrophoresis 2009; 30 Suppl 1:S156-61. [DOI: 10.1002/elps.200900098] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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11
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Young C, Truman P, Boucher M, Keyzers RA, Northcote P, Jordan TW. The algal metabolite yessotoxin affects heterogeneous nuclear ribonucleoproteins in HepG2 cells. Proteomics 2009; 9:2529-42. [DOI: 10.1002/pmic.200800725] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Zhao TT, Graber TE, Jordan LE, Cloutier M, Lewis SM, Goulet I, Côté J, Holcik M. hnRNP A1 regulates UV-induced NF-κB signalling through destabilization of cIAP1 mRNA. Cell Death Differ 2008; 16:244-52. [DOI: 10.1038/cdd.2008.146] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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13
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Rho JH, Qin S, Wang JY, Roehrl MHA. Proteomic expression analysis of surgical human colorectal cancer tissues: up-regulation of PSB7, PRDX1, and SRP9 and hypoxic adaptation in cancer. J Proteome Res 2008; 7:2959-72. [PMID: 18549262 DOI: 10.1021/pr8000892] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Colorectal adenocarcinoma is one of the worldwide leading causes of cancer deaths. Discovery of specific biomarkers for early detection of cancer progression and the identification of underlying pathogenetic mechanisms are important tasks. Global proteomic approaches have thus far been limited by the large dynamic range of molecule concentrations in tissues and the lack of selective enrichment of the low-abundance proteome. We studied paired cancerous and normal clinical tissue specimens from patients with colorectal adenocarcinomas by heparin affinity fractionation enrichment (HAFE) followed by 2-D PAGE and tandem mass spectrometric (MS/MS) identification. Fifty-six proteins were found to be differentially expressed, of which 32 low-abundance proteins were only detectable after heparin affinity enrichment. MS/MS was used to identify 5 selected differentially expressed proteins as proteasome subunit beta type 7 (PSB7), hemoglobin alpha subunit (HBA), peroxiredoxin-1 (PRDX1), argininosuccinate synthase (ASSY), and signal recognition particle 9 kDa protein (SRP9). This is the first proteomic study detecting the differential expression of these proteins in human colorectal cancer tissue. Several of the proteins are functionally related to tissue hypoxia and hypoxic adaptation. The relative specificities of PSB7, PRDX1, and SRP9 overexpression in colon cancer were investigated by Western blot analysis of patients with colon adenocarcinomas and comparison with a control cohort of patients with lung adenocarcinomas. Furthermore, immunohistochemistry on tissue sections was used to define the specific locations of PSB7, PRDX1, and SRP9 up-regulation within heterogeneous primary human tumor tissue. Overexpression of the three proteins was restricted to the neoplastic cancer cell population within the tumors, demonstrating both cytoplasmic and nuclear localization of PSB7 and predominantly cytoplasmic localization of PRDX1 and SRP9. In summary, we describe heparin affinity fractionation enrichment (HAFE) as a prefractionation tool for the study of the human primary tissue proteome and the discovery of PSB7, PRDX1, and SRP9 up-regulation as candidate biomarkers of colon cancer.
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Affiliation(s)
- Jung-hyun Rho
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
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Tan HT, Tan S, Lin Q, Lim TK, Hew CL, Chung MC. Quantitative and Temporal Proteome Analysis of Butyrate-treated Colorectal Cancer Cells. Mol Cell Proteomics 2008; 7:1174-85. [DOI: 10.1074/mcp.m700483-mcp200] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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15
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Kondo T, Hirohashi S. Application of highly sensitive fluorescent dyes (CyDye DIGE Fluor saturation dyes) to laser microdissection and two-dimensional difference gel electrophoresis (2D-DIGE) for cancer proteomics. Nat Protoc 2007; 1:2940-56. [PMID: 17406554 DOI: 10.1038/nprot.2006.421] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Proteome data combined with histopathological information provides important, novel clues for understanding cancer biology and reveals candidates for tumor markers and therapeutic targets. We have established an application of a highly sensitive fluorescent dye (CyDye DIGE Fluor saturation dye), developed for two-dimensional difference gel electrophoresis (2D-DIGE), to the labeling of proteins extracted from laser microdissected tissues. The use of the dye dramatically decreases the protein amount and, in turn, the number of cells required for 2D-DIGE; the cells obtained from a 1 mm2 area of an 8-12 microm thick tissue section generate up to 5,000 protein spots in a large-format 2D gel. This protocol allows the execution of large-scale proteomics in a more efficient, accurate and reproducible way. The protocol can be used to examine a single sample in 5 d or to examine hundreds of samples in large-scale proteomics.
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Affiliation(s)
- Tadashi Kondo
- Proteome Bioinformatics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
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16
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Vávrová J, Janovská S, Rezácová M, Hernychová L, Tichá Z, Vokurková D, Záskodová D, Lukásová E. Proteomic analysis of MOLT-4 cells treated by valproic acid. Mol Cell Biochem 2007; 303:53-61. [PMID: 17426928 DOI: 10.1007/s11010-007-9455-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Accepted: 03/14/2007] [Indexed: 01/13/2023]
Abstract
The effect of valproic acid (VA) on protein expression in human T-lymphocytic leukemia cells MOLT-4 was studied. VA is an inhibitor of histonedeacetylases and has a potential use as antitumor agent in leukemia treatment. The authors in this work prove that 4 h long incubation with 2 mmol/l VA causes phosphorylation of histone H2A.X and its colocalization with 53BP1 in nuclear foci. Their co-localization is typical for DSB signaling machinery. These foci were detected in cells after 4 h exposure without increase of Annexin V positive apoptotic cells. Slight increase in apoptosis (Annexin V positivity) after 24 h is accompanied by more intensive increase in phosphorylation of H2A.X and also by formation of nuclear foci containing gammaH2A.X and 53BP1. Treatment of cells with 2 mmol/l VA resulted in induction of apoptosis affecting about 30% of cells after incubation for 72 h. The changes in protein expression were examined after cell incubation with 2 mmol/l VA for 4 h. Proteins were separated by two-dimensional electrophoresis and quantified using image evaluation system. Those exhibiting significant VA-induced abundance alterations were identified by mass spectrometry. Changes in expression of 22 proteins were detected, of which 15 proteins were down-regulated. Proteomic analysis resulted in successful identification of three proteins involving alfa-tubulin 3, tubulin-specific chaperone and heterogeneous nuclear ribonucloprotein F. Expression of seven proteins was up-regulated, including heterogeneous nuclear ribonucloprotein A/B. Identified proteins are related to microtubular system and hnRNP family. Suppression of microtubular proteins and changes of balance among hnRNPs can contribute to proliferation arrest and apoptosis induction.
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Affiliation(s)
- Jirina Vávrová
- Department of Radiobiology and Department of Molecular Pathology, School of Military Health Sciences Hradec Králové, University of Defense Brno, Trebesská 1575, 500 01, Hradec Kralove, Czech Republic.
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Hrebicek T, Dürrschmid K, Auer N, Bayer K, Rizzi A. Effect of CyDye minimum labeling in differential gel electrophoresis on the reliability of protein identification. Electrophoresis 2007; 28:1161-9. [PMID: 17340647 DOI: 10.1002/elps.200600639] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Differential 2-DE (DIGE) is a widely applied tool for the quantitative analysis of differentially represented proteins. The method involves covalent minimal labeling of proteins prior to their electrophoretic separation using CyDye DIGE Fluor minimal dyes. This methodology creates two different species per protein, the labeled (approx. 1-2%) and unlabeled (approx. 98-99%) ones, which differ in their molecular masses by 434-464 Da, depending on the attached dye. DIGE followed by automated spot picking according to the CyDye coordinates misses in many instances the exact positions where the maximum amounts of the considered proteins are located. This fact leads to a loss in sensitivity of the subsequent MALDI-MS analyses and results in a reduced reliability of protein identification and sequence coverage. In this paper, the migration differences of labeled and unlabeled species are quantified together with the impact of this effect on the certainty of protein identification and sequence coverage investigating proteins up to 90 kDa.
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Affiliation(s)
- Thomas Hrebicek
- Institute of Analytical Chemistry and Food Chemistry, University of Vienna, Vienna, Austria
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Lewis SM, Veyrier A, Hosszu Ungureanu N, Bonnal S, Vagner S, Holcik M. Subcellular relocalization of a trans-acting factor regulates XIAP IRES-dependent translation. Mol Biol Cell 2007; 18:1302-11. [PMID: 17287399 PMCID: PMC1838995 DOI: 10.1091/mbc.e06-06-0515] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Revised: 01/19/2007] [Accepted: 01/31/2007] [Indexed: 01/15/2023] Open
Abstract
Translation of the X-linked inhibitor of apoptosis (XIAP) proceeds by internal ribosome entry site (IRES)-mediated initiation, a process that is physiologically important because XIAP expression is essential for cell survival under conditions of compromised cap-dependent translation, such as cellular stress. The regulation of internal initiation requires the interaction of IRES trans-acting factors (ITAFs) with the IRES element. We used RNA-affinity chromatography to identify XIAP ITAFs and isolated the heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1). We find that hnRNP A1 interacts with XIAP IRES RNA both in vitro and in vivo and that hnRNP A1 negatively regulates XIAP IRES activity. Moreover, XIAP IRES-dependent translation is significantly reduced when hnRNP A1 accumulates in the cytoplasm. Osmotic shock, a cellular stress that causes cytoplasmic accumulation of hnRNP A1, also leads to a decrease in XIAP levels that is abrogated by knockdown of hnRNP A1 expression. These results suggest that the subcellular localization of hnRNP A1 is an important determinant of its ability to negatively regulate XIAP IRES activity, suggesting that the subcellular distribution of ITAFs plays a critical role in regulating IRES-dependent translation. Our findings demonstrate that cytoplasmic hnRNP A1 is a negative regulator of XIAP IRES-dependent translation, indicating a novel function for the cytoplasmic form of this protein.
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Affiliation(s)
- Stephen M. Lewis
- *Apoptosis Research Centre, Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, K1H 8L1, Canada
| | - Anne Veyrier
- INSERM U563, Toulouse, F-31000, France
- Institut Claudius Régaud, Toulouse, F-31052, France; and
- Université Toulouse III Paul Sabatier, Toulouse, F-31000, France
| | - Nicoleta Hosszu Ungureanu
- *Apoptosis Research Centre, Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, K1H 8L1, Canada
| | - Sophie Bonnal
- INSERM U563, Toulouse, F-31000, France
- Institut Claudius Régaud, Toulouse, F-31052, France; and
- Université Toulouse III Paul Sabatier, Toulouse, F-31000, France
| | - Stéphan Vagner
- INSERM U563, Toulouse, F-31000, France
- Institut Claudius Régaud, Toulouse, F-31052, France; and
- Université Toulouse III Paul Sabatier, Toulouse, F-31000, France
| | - Martin Holcik
- *Apoptosis Research Centre, Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, K1H 8L1, Canada
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