Structural and Functional Studies of Mtr4 and Mtr4-mediated Complexes

Mtr4 和 Mtr4 介导的复合物的结构和功能研究

• 批准号: 9009671
• 负责人: SEAN J JOHNSON
• 金额: $ 25.03万
• 依托单位: UTAH STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-30 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9009671
• 关键词: Address; Biochemical; Cell Nucleus; Cell physiology; Characteristics; Complex; Cytosol; Disease; Event; Excision; In Vitro; Individual; Lead; Link; Malignant Neoplasms; Mediating; Modeling; Molecular; Mutation; Neurodegenerative Disorders; Nuclear; Pathway interactions; Phosphodiesterase I; Play; Process; Protein Binding; Protein Subunits; Proteins; RNA; RNA Degradation; RNA Helicase; RNA Processing; Role; Structure; Substrate Interaction; Substrate Specificity; System; base; endonuclease; genetic analysis; helicase; in vivo; novel; prevent; public health relevance; research study

 DESCRIPTION (provided by applicant) The integrity and availability of cellular RNA is tightly regulated by a variety of RNA processing, turnover, and surveillance pathways. The eukaryotic exosome plays a major role in the processing and degradation of a wide variety of RNAs in both the nucleus and cytosol. Several protein factors associate with the exosome to identify appropriate RNA substrates and activate exosome activity. A major challenge is to understand the molecular details of how these proteins interact with RNA substrates and with each other to achieve substrate specificity. Notably, the only protein factor that is required for all known activities of the nuclear exosome i the RNA helicase, Mtr4. Given this central role in exosome activation, there is a critical need to understand how Mtr4 functions, how it interacts with RNA substrates, and how it mediates and is influenced by assembly of other exosome activating factors. Recent studies indicate that the arch domain of Mtr4 plays a previously unrecognized role in unwinding RNA substrates. The underlying basis for this observation is unclear, but is proposed to be a function of substrate interactions that connect the arch to the core helicase domains. The detailed interactions between Mtr4 and other complexes, such as the TRAMP complex, are also poorly understood. This project seeks to define the molecular basis for Mtr4 function by employing a variety of biochemical and structural approaches, combined with in vivo genetic analysis. The specific aims of this project are to (1) describe the role of the arch domain in RNA recognition and unwinding, and (2) characterize Mtr4 interactions with protein binding partners.

 描述（由申请人提供） 细胞 RNA 的完整性和可用性受到各种 RNA 加工的严格调控， 真核外泌体在细胞核和细胞质中多种 RNA 的加工和降解中发挥着重要作用，多种蛋白质因子与外泌体相关，以识别适当的 RNA 底物并激活外泌体 A 主要活性。挑战在于了解这些蛋白质如何与 RNA 底物相互作用以及如何相互相互作用以实现底物特异性。值得注意的是，RNA 解旋酶是核外泌体所有已知活性所需的唯一蛋白质因子。由于 Mtr4 在外泌体激活中发挥着核心作用，因此迫切需要了解 Mtr4 的功能、它如何与 RNA 底物相互作用以及它如何介导其他外泌体激活因子的组装并受其影响。最近的研究表明，Mtr4 的拱形结构域发挥着重要作用。之前未认识到的在解旋 RNA 底物中的作用尚不清楚，但推测是连接拱与核心解旋酶结构域的底物相互作用的函数。对 TRAMP 复合物等复合物的了解也很少。该项目旨在通过采用各种生化和结构方法，结合体内遗传分析来定义 Mtr4 功能的分子基础。 1) 描述 arch 结构域在 RNA 识别和解旋中的作用，(2) 描述 Mtr4 与蛋白质结合伙伴的相互作用。