Analysis of the VHL-HIF hydroxylase pathway

VHL-HIF羟化酶途径分析

• 批准号: 7500280
• 负责人: YUZURU SHIIO
• 金额: $ 22.19万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-25 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7500280
• 关键词: Affinity; Affinity Chromatography; Apoptosis; Bacteriophages; Binding; Binding Proteins; Biochemical; Biogenesis; Biological; Biological Phenomena; Biological Process; Biology; Cells; Code; Complex; EP300 gene; Hydroxylation; Hypoxia Inducible Factor; Inherited; Iron; Iron Chelation; Isotopes; Isotopically-Coded Affinity Tagging; MYBBP1A gene; Mediating; Mediator of activation protein; Methods; Mixed Function Oxygenases; Molecular Profiling; Mutation; Numbers; Oncogene Proteins; Oncogenes; Oxidative Phosphorylation; Oxygen; Pathway interactions; Pheochromocytoma; Play; Post-Translational Protein Processing; Proline; Proteins; Proteomics; Renal Cell Carcinoma; Role; Screening procedure; Technology; Transcription Coactivator; Tumor Angiogenesis; Tumor Suppression; Tumor Suppressor Genes; Ubiquitin; Ubiquitination; VHL mutation; anticancer research; base; expression cloning; follow-up; hemangioblastoma; interest; multicatalytic endopeptidase complex; novel; novel strategies; protein expression; tumor; tumorigenesis; ubiquitin ligase

DESCRIPTION (provided by applicant): Protein modification with ubiquitin plays key regulatory roles in a wide variety of biological phenomena including tumorigenesis. Several oncoproteins and anti-oncoproteins display ubiquitin ligase activity and identification of their substrates is one of the central themes in cancer research. This application is directed toward understanding the biological roles of a tumor-suppressing ubiquitin ligase, VHL. VHL is currently best understood as a negative regulator of hypoxia inducible factor (HIF). In the presence of oxygen and iron, specific proline residues in HIF are hydroxylated and these hydroxylated prolines are recognized by VHL, which results in ubiquitination and degradation of HIF. VHL mutation is associated with hereditary and sporadic renal cell carcinomas, hemangioblastomas, and pheochromocytomas. Several lines of evidence suggest that, in addition to HIF, there are unidentified substrates for VHL which play critical roles in tumor suppression. A major barrier to understanding the VHL functions (as well as the functions of other ubiquitin ligases) has been the difficulty in pinpointing its ubiquitination substrates. Employing a novel quantitative proteomics technology, ICAT (isotope-coded affinity tag), we developed an approach to systematically identify the substrates of ubiquitin ligases and using this method, we identified a novel substrate for VHL, which carries the character of a key mediator of VHL functions. Therefore the aims of this application are to analyze the mechanism and biological consequence of ubiquitination of this substrate and to conduct further proteomic screens to identify additional substrates for VHL. These studies should provide a better understanding of the biological functions of VHL and advance the nascent field of proteomics-based biology.

描述（由申请人提供）：泛素修饰的蛋白质修饰在包括肿瘤发生在内的多种生物学现象中起关键的调节作用。几种癌细胞蛋白和抗蛋白素表现出泛素连接酶的活性，其底物的鉴定是癌症研究的中心主题之一。该应用是针对理解肿瘤抑制泛素连接酶VHL的生物学作用。目前最好将VHL理解为缺氧诱导因子（HIF）的负调节剂。在存在氧和铁的情况下，HIF中的特异性脯氨酸残基是羟基化的，这些羟基化脯氨酸被VHL识别，这会导致HIF的泛素化和降解。 VHL突变与遗传性和零星的肾细胞癌，血管细胞母细胞瘤和嗜铬细胞瘤有关。几条证据表明，除HIF外，还有一些未鉴定的VHL底物在肿瘤抑制中起着关键作用。理解VHL功能（以及其他泛素连接酶的功能）的主要障碍一直是确定其泛素化底物的困难。我们采用了一种新型的定量蛋白质组学技术（同位素编码的亲和力标签），我们开发了一种系统地识别泛素连接酶的底物并使用这种方法，我们确定了VHL的新型底物，VHL具有VHL功能的关键介体特征。因此，本应用的目的是分析该基材泛素化的机制和生物学后果，并进行进一步的蛋白质组学筛选以鉴定VHL的其他底物。这些研究应更好地了解VHL的生物学功能，并推进基于蛋白质组学的生物学的新生领域。