Compositional Analysis of the Arabidopsis 26S Proteasome

描述(申请人提供)：本研究的目标是以拟南芥为模型，揭示多细胞真核生物中26S蛋白酶体的分子组成和功能。生物体的各种基本功能依赖于蛋白质的降解，包括维持游离氨基酸库、去除受损的蛋白质和控制调节蛋白质的丰度。这种分解的主要机制是26S蛋白酶体，它是一种依赖于ATP的2-丙二醛蛋白分解复合体。本项目的具体目的是确定拟南芥天然26S蛋白酶体的组成，揭示各种亚基的功能，并确定植物是否通过各种亚型的选择性配对来优先组装特定亚型的复合体。对26S蛋白酶体的更完整的描述将有助于更深入地了解蛋白质是如何选择性降解的，这可能会发现控制体内蛋白质分解的新方法。鉴于Ub和26S蛋白酶体在真核生理和发育的几乎所有方面的重要性，这项工作将对医学和农业都有实际意义，包括由于泛素/26S蛋白酶体系统缺陷而引起的各种疾病。

DESCRIPTION (provided by applicant): The goal of this research is to reveal the molecular composition and functions of the 26S proteasome in a multicellular eukaryote, using Arabidopsis thaliana as the model. Organisms rely on protein degradation for a variety of essential functions, including the maintenance of free amino acid pools, the removal of damaged proteins, and the control of regulatory protein abundance. The major machine for this breakdown is the 26S proteasome, an ATP-dependent 2-MDa proteolytic complex. The specific aim of this project is to define the composition of the native 26S proteasome from Arabidopsis, reveal the functions of various subunits, and determine whether the plant preferentially assembles specific subtypes of the complex through selective pairing of various isoforms. A more complete characterization of the 26S proteasome will lead to a deeper understanding of how proteins are selectively degraded which may potentially identify new ways to control protein breakdown in vivo. Given the importance of Ub and the 26S proteasome to almost all facets of eukaryotic physiology and development, this work should have practical benefits to both medicine and agriculture, including various disease caused by defects in the Ubiquitin/26S proteasome system.