Conformational switching during the production of branched polyubiquitin chains (A13*)

支链多泛素链生产过程中的构象转换 (A13*)

• 批准号: 447461584
• 金额: --
• 依托单位: Abteilung Molekulare Maschinen und Signalwege
• 依托单位国家: 德国
• 项目类别: Collaborative Research Centres
• 财政年份: 2021
• 资助国家: 德国
• 起止时间: 2020-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/447461584?language=en
• 关键词: Conformational; switching; during; production; branched

Post-translational modification by ubiquitin chains is a major form of eukaryotic protein regulation. Although much is known about E1-E2-E3 trienzyme cascades linking ubiquitin to target proteins, the dynamic structural mechanisms underlying formation of specific ubiquitin chains – and particularly roles of E4 enzymes – are poorly understood. In this project, we will investigate the mechanisms of conformational switching during generation and recognition of specific "branched" ubiquitin chains (wherein lysines 29 and 48 of an individual molecule of ubiquitin are both isopeptide bonded to additional ubiquitin molecules) by E1-E2-E3-E4 tetraenzyme cascades. Biochemistry, chemistry, X-ray crystallography, and cryo EM will be used to elucidate the dynamic conformational cycles by which three individual ubiquitins are site-specifically adjoined by E2-E3 and E2-E4 enzyme pairs. Furthermore, principles of polyubiquitylation will be determined.

泛素链的翻译后修饰是真核生物蛋白质调控的主要形式。尽管人们对E1-E2-E3三酶级联反应的了解很多，但对特定泛素链形成的动力学结构机制，特别是E4酶的作用，还知之甚少。在这个项目中，我们将研究特定的“分支”泛素链（其中泛素的单个分子的赖氨酸29和48都是与其他泛素分子键合的异肽）通过E1-E2-E3-E4四酶级联产生和识别过程中的构象转换机制。生物化学，化学，X-射线晶体学和冷冻电镜将被用来阐明动态构象循环，其中三个单独的泛素是由E2-E3和E2-E4酶对位点特异性邻接。此外，将确定多泛素化的原理。