The Enzymatic Pathway of a Ubiquitin-Like Modification

泛素样修饰的酶途径

基本信息

批准号：
7541369
负责人：
Yuan Chen
金额：
$ 36.69万
依托单位：
BECKMAN RESEARCH INSTITUTE/CITY OF HOPE
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-01-01 至 2010-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7541369
关键词：
Accounting Active Sites Amino Acid Sequence Binding Binding Sites Biochemical Biological Assay Biological Models C-terminal Catalysis Catalytic Domain Chemistry Complex Conserved Sequence DNA Repair Enzymatic Biochemistry Enzyme Kinetics Enzymes Genetic Transcription Goals Knowledge Malignant Neoplasms Mediating Modification Mutation NMR Spectroscopy Names Nature Nobel Prize Pathway interactions Phosphorylation Post-Translational Protein Processing Protein translocation Proteins Reaction Recruitment Activity Regulation Research Personnel Role Scientist Site Specificity Structure Study Section Tissues Ubiquitin Ubiquitin Like Proteins Ubiquitination Variant chemical reaction enzyme mechanism improved novel programs protein complex therapeutic target ubiquitin-protein ligase

Accounting Active Sites Amino Acid Sequence Binding Binding Sites Biochemical Biological Assay Biological Models C-terminal Catalysis Catalytic Domain Chemistry Complex Conserved Sequence DNA Repair Enzymatic Biochemistry Enzyme Kinetics Enzymes Genetic Transcription Goals Knowledge Malignant Neoplasms Mediating Modification Mutation NMR Spectroscopy Names Nature Nobel Prize Pathway interactions Phosphorylation Post-Translational Protein Processing Protein translocation Proteins Reaction Recruitment Activity Regulation Research Personnel Role Scientist Site Specificity Structure Study Section Tissues Ubiquitin Ubiquitin Like Proteins Ubiquitination Variant chemical reaction enzyme mechanism improved novel programs protein complex therapeutic target ubiquitin-protein ligase

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项目摘要

Ubiquitin-like modifications are similar to other macromolecular chemistry, such as transcription and DMArepair, in that they require multiple steps that are carried out by multi- protein complexes. Better understanding of how the multi-protein machinery catalyzes ubiquitin- like modifications is fundamentally important and will significantly improve our knowledge of how multi-protein complexes carry out macromolecular chemistry. The overall goal of this proposal is to investigate the enzymology of protein modifications by the small ubiquitin-like modifier (SUMO). Sumoylation, which is established as an important post-translational modification, is a good model system for enzymology studies, and has been proposed as a cancer therapeutic target, because of the increased levels of its enzymes in cancers. A mystery about the enzymology is that the binding substrates are too far apart from the catalytic sites in crystal structures to account for catalysis, and the prevailing view is that conformational changes must take place to bring them into close proximity. As shown in our Preliminary Studies section, while the available structures are stable complexes, less stable interactions that have not been characterized are critical to the enzymatic cycle. We will investigate how the weaker interactions may guide substrate translocations to catalytic active sites, and induce allosteric effects in the enzymes. We will use NMR spectroscopy in structural studies, which is especially suitable for characterizing weak protein complexes. Complementary biochemical and enzyme kinetic analysis will be used to identify the role of each interaction in the enzyme mechanism. The proposed studies will likely result in a paradigm shift regarding the enzymes catalyzing ubiquitin-like modifications, and improve our knowledge of the themes and variations of how multi-protein machineries catalyze macromolecular reactions.

泛素样修饰类似于其他大分子化学，例如转录和dmarepair，因为它们需要多个步骤蛋白质复合物。更好地了解多蛋白质机械如何催化泛素 - 像修改一样，从根本上来说很重要，并且将大大提高我们对如何的了解多蛋白质复合物进行大分子化学。该提案的总体目标是研究蛋白质修饰的酶学由小型泛素样修饰剂（SUMO）。 sumoylation，被确定为重要翻译后修饰是用于酶学研究的良好模型系统，并且已经是提议作为癌症治疗靶点，因为其酶的水平增加癌症。关于酶学的一个谜是，绑定的底物与晶体结构中的催化位点可以解释催化，而普遍的观点是必须进行构象变化，以使它们近乎接近。如我们所示初步研究部分，虽然可用的结构是稳定的复合物，但较不稳定尚未表征的相互作用对于酶促循环至关重要。我们将研究较弱的相互作用如何引导底物易位到催化活性位点，并在酶中诱导变构作用。我们将在结构中使用NMR光谱研究特别适合表征弱蛋白质复合物。补充生化和酶动力学分析将用于确定每种相互作用在酶机制。拟议的研究可能会导致有关酶催化泛素样修饰，并提高我们对主题和主题的了解多蛋白机制如何催化大分子反应的变化。