FUNCTIONS OF UBIQUITIN-CONTAINING PROTEINS

含泛素蛋白质的功能

• 批准号: 3279585
• 负责人: ALEXANDER J VARSHAVSKY
• 金额: $ 20.19万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-07-01 至 1995-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3279585
• 关键词: binding proteins; biological signal transduction; chemical conjugate; chimeric proteins; developmental genetics; enzyme mechanism; enzyme substrate complex; fungal genetics; fusion gene; gel electrophoresis; genetic manipulation; genetic mapping; laboratory mouse; molecular chaperones; molecular cloning; molecular genetics; mutant; nucleic acid sequence; nucleoproteins; polysaccharides; protein degradation; protein sequence; protein structure; proteolysis; radiotracer; stress proteins; ubiquitin; yeasts

One function of ubiquitin, a highly conserved 76-residue protein, is to serve as a signal for degradation of conjugated acceptor proteins. More recent work [1] has identified another,"chaperone" function of ubiquitin, in which its covalent association with other proteins promotes formation of specific cellular structures [1]. Studies of the last several years, and in particular studies supported by the present grant, have demonstrated the involvement of ubiquitin-dependent processes in a remarkably broad range of cellular functions, from protein degradation and maturation to cell cycle control, stress response and DNA repair. The objective of the research described in this renewal application is to advance the understanding of the ubiquitin system. Specific Aims: 1) Molecular genetic analysis of the yeast (S. cerevisiae) Ub-activating enzyme (E1, encoded by the UBA1 gene), and the use of conditional ubal mutants to test Ub involvement in the degradation of specific short-lived proteins. 2) Molecular genetic analysis of the yeast Ub-conjugating enzymies (E2's, encoded by the UBC1-UBC8 genes), and identification of E2's that function in the N-end rule pathway of protein degradation. 3) Studies on Ub-related aspects of the yeast N-end-recognizing protein (E3) encoded by the UBR1 gene. 4) Molecular genetic analysis of the yeast Ub-specific proteases (encoded by UBP genes) that cleave Ub off its linear or branched conjugates with itself or other proteins. 5) Using non-deubiquitinatable Ub fusions (Ub-Pro-Betagal or (Ub-Val76)-Met-Betagal) to dissect a proteolytic pathway that recognizes a single Ub moiety as degradation signal and is distinct from the N-end rule pathway. 6) Construction of Ub bearing a peptide tag, and its use to detect and identify specific constitutive and stress-inducible Ub conjugates in S. cerevisiae. 7) Further biochemical and genetic analyses of the in vivo ubiquitination and degradation of the yeast MATAlpha2 repressor. 8) Cloning and functional analysis of mammalian (mouse) genes that encode Ub-related components of the N-end rule pathway.

泛素的一种功能，一种高度保守的76个残留蛋白，是 用作降解共轭受体蛋白的信号。 更多的 最近的工作[1]确定了泛素的另一个“伴侣”功能， 其中其与其他蛋白质的共价关联促进了形成 特定的细胞结构[1]。 过去几年的研究 特别是本赠款支持的研究表明 泛素依赖性过程的参与非常广泛 细胞功能的范围，从蛋白质降解和成熟到 细胞周期控制，应力反应和DNA修复。目的 此续签应用中描述的研究是为了促进 了解泛素系统。 具体目的： 1）酵母（酿酒酵母）UB激活的分子遗传分析 酶（E1，由UBA1基因编码），并使用条件UBAL 突变体测试UB参与特定短暂寿命的降解 蛋白质。 2）酵母UB偶联酶的分子遗传分析（E2， 由UBC1-UBC8基因编码），并识别E2的功能 在蛋白质降解的N端规则途径中。 3）研究酵母N端识别蛋白的UB相关方面 （E3）由UBR1基因编码。 4）酵母UB特异性蛋白酶的分子遗传分析（编码 由UBP基因）与UB的线性或分支结合物裂开 本身或其他蛋白质。 5）使用不可用的UB融合（UB-Pro-Betagal或 （ub-val76） - met-betagal）剖析识别的蛋白水解途径 单个UB部分作为降解信号，与N端不同 规则路径。 6）构建带有肽标签的UB，并用于检测和使用 确定特定的本构和应力诱导的UB偶联物。 酿酒酵母。 7）进一步的生化和遗传分析的体内泛素化 和酵母Matalpha2抑制剂的降解。 8）编码的哺乳动物（小鼠）基因的克隆和功能分析 N端规则途径的UB相关组件。