Molecular Interactions of Rnf13, a Ubiquitin Ligase in Endosome Membranes

内体膜中泛素连接酶 Rnf13 的分子相互作用

• 批准号: 0544095
• 负责人: Ann Erickson
• 金额: --
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0544095&HistoricalAwards=false
• 关键词: Molecular; Interactions; Rnf13; Ubiquitin; Ligase

Lysosomal proteases mediate cleavage events within cellular vesicles, but they can also be secreted and so mediate proteolysis outside cells. The lysosomal protease precursor procathepsin L can be stored in specialized cellular vesicles that can, at least in certain cell types, be induced to secrete their contents to the cell exterior. This project seeks to determine whether targeting of the proprotease to these vesicles is mediated by Rnf13, a newly discovered integral membrane protein that has a domain structure similar to that of a protein shown to mediate targeting of enzymes to structurally similar plant protein storage bodies. To understand the role of Rnf13 in the cellular targeting and secretion of a lysosomal protease, the biosynthesis of Rnf13 will be characterized and binding of this membrane protein to the protease will be assayed. The studies will establish the cellular route followed by this membrane protein and the nature and role of modifications that it undergoes after its synthesis. As a step toward establishing physiological functions of Rnf13, binding assays and mass spectrometry will be performed to identify proteins that interact with this uncharacterized multi-domain integral membrane protein. A central priority of the project is the recruitment of undergraduates, with a particular focus on underrepresented minorities, to the research group. These students will participate extensively in all aspects of the experimental work.

溶酶体蛋白酶介导细胞囊泡内的裂解事件，但它们也可以分泌，因此介导细胞外的蛋白水解。溶酶体蛋白酶前体血凝素原L可以储存在专门的细胞囊泡中，至少在某些细胞类型中，这些细胞囊泡可以被诱导将其内容物分泌到细胞外部。该项目旨在确定proprotease靶向这些囊泡是否由Rnf13介导，Rnf13是一种新发现的完整膜蛋白，其结构域结构类似于一种被证明介导酶靶向结构相似的植物蛋白储存体的蛋白质。为了了解Rnf13在溶酶体蛋白酶的细胞靶向和分泌中的作用，我们将对Rnf13的生物合成进行表征，并分析该膜蛋白与蛋白酶的结合情况。这些研究将确定这种膜蛋白的细胞途径，以及它在合成后所经历的修饰的性质和作用。作为确定Rnf13生理功能的一步，将进行结合分析和质谱分析，以鉴定与这种未表征的多结构域整体膜蛋白相互作用的蛋白质。该项目的中心优先事项是招募本科生，特别关注代表性不足的少数民族，以研究小组。这些学生将广泛参与实验工作的各个方面。