Inner Membrane Protein Assembly in Bacteria

细菌内膜蛋白质组装

基本信息

批准号：
7924951
负责人：
ROSS E DALBEY
金额：
$ 12万
依托单位：
OHIO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-09-30 至 2011-05-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): More than 30% of the proteins in all living cells must be transported across or integrated into a membrane, and many of the factors that promote protein insertion are essential for cell viability. Bacteria use two pathways to promote protein insertion into the plasma membrane. The Sec machinery is responsible for inserting the majority of the proteins into the membrane after targeting by the SRP/FtsY components. However, there is also a class of proteins that insert independent of the Sec machinery. These proteins require a novel protein called YidC, which was discovered in the year 2000. YidC is essential for bacterial cell growth, and is evolutionary conserved with homologs in mitochondria and chloroplasts. YidC also works with the Sec machinery to mediate membrane protein insertion. For Sec-dependent proteins, YidC has been proposed to play a role in the lateral transfer of membrane proteins into the lipid bilayer and to function as an assembly site to promote folding of transmembrane domains of membrane proteins. The goal of this research is to understand the exact role of YidC in membrane protein biogenesis. We plan to pursue the following specific aims: (1) Determine the substrate specificity of YidC; (2) Identify the substrate binding region and the organization of the transmembrane domains within the YidC protein; (3) Determine the relationship between YidC, SecYEG, ribosome, SRP/FtsY, and the proteins involved in membrane protein integration; and (4) Determine the function of YidC in membrane protein biogenesis. These studies should impact the field of bacterial membrane protein biogenesis and advance the knowledge of analogous pathways in eukaryotic cells.

描述（申请人提供）：所有活细胞中超过30％的蛋白质必须跨或整合到膜中，并且促进蛋白质插入的许多因素对于细胞活力是必不可少的。细菌使用两种途径促进蛋白质插入质膜。 SEC机械负责在SRP/FTSY组件靶向后将大多数蛋白质插入膜中。但是，还有一类蛋白质独立于SEC机械插入。这些蛋白质需要一种称为YIDC的新型蛋白质，该蛋白质是在2000年发现的。YIDC对于细菌细胞生长至关重要，并且在线粒体和叶绿体中具有同源物的进化保守。 YIDC还与SEC机械一起介导膜蛋白插入。对于SEC依赖性蛋白，已提出YIDC在膜蛋白向脂质双层中的横向转移中发挥作用，并用作促进膜蛋白跨膜结构域折叠的组装位点。这项研究的目的是了解Yidc在膜蛋白生物发生中的确切作用。我们计划追求以下特定目标：（1）确定YIDC的底物特异性；（2）确定YIDC蛋白内跨膜结构域的底物结合区域和组织；（3）确定YIDC，Secyeg，核糖体，SRP/FTSY和涉及膜蛋白整合的蛋白之间的关系；（4）确定YIDC在膜蛋白生物发生中的功能。这些研究应影响细菌膜蛋白生物发生的领域，并促进真核细胞中类似途径的知识。