Structural Virology of Tripartite Motif Proteins

描述（由申请人提供）：三方基序或TRIM蛋白包括环结构域E3泛素连接酶的最大超家族。这些酶在多种重要的细胞过程中发挥作用，特别是在先天抗病毒反应机制中。TRIM蛋白的一个决定性特征是它们由多个结构域组成，每个结构域赋予蛋白质特定的生化功能。对于这些研究，我们特别关注TRIM5j，它在细胞中作为抑制HIV-1复制的限制因子发挥作用。我们建议：(1)确定一个完整的三方基序的结构，以了解不同组成域如何在结构上相互整合的分子细节。我们还将确定控制二聚化和高阶组装的分子原理，这是TRIM蛋白功能的重要组成部分。(2)明确TRIM5j的不同结构域如何协调其生化活动，以识别HIV-1的入侵衣壳并限制病毒复制。我们将采用多组分、综合的方法，结合结构、生化和细胞生物学技术。预期的结果是对trim5j介导的HIV-1复制抑制的全面的、分子水平的理解。

DESCRIPTION (provided by applicant): Tripartite motif or TRIM proteins comprise the largest superfamily of RING-domain E3 ubiquitin ligases. These enzymes function in a wide variety of important cellular processes, particularly in innate antiviral response mechanisms. A defining feature of TRIM proteins is that they are composed of multiple domains, with each domain conferring a specific biochemical functionality to the protein. For these studies, we have a special focus on TRIM5j, which functions in the cell as a restriction factor that inhibits HIV-1 replication. We propose to: (1) Determine the structure of a complete tripartite motif in order to understand the molecular details of how the different constituent domains integrate structurally with each other. We will also determine the molecular principles that govern dimerization and higher-order assembly, which are important elements of TRIM protein function. (2) Define how the different domains of TRIM5j coordinate their biochemical activities, in order to recognize the incoming capsids of HIV-1 and restrict viral replication. We will use a multi-component, integrative approach that combines structural, biochemical, and cell biological techniques. The expected outcome is a comprehensive, molecular level understanding of TRIM5j-mediated inhibition of HIV-1 replication.