Drs2p Function in Clathrin-coated Vesicle Budding

描述(申请人摘要)：真核细胞的显著特征， 从酵母菌到人类，它们的隔间组织是不是被膜所束缚 细胞器，每个细胞器都有独特的组成和功能。的长期目标是 这个研究项目是为了了解Goigi建筑群是如何 多隔室细胞器，在运输中发挥其基本作用， 蛋白质在分泌途径中的修饰和分类。朝向这个方向 目的：腺苷二磷酸核糖化因子(ARF)在囊泡介导中的作用 来自高尔基建筑群的运输正在接受检查。ARF似乎在规范 高尔基复合体中包被COPI和笼状蛋白的囊泡均萌发。这个 拟议的研究源于最近的发现，表明Drs2p和And 完整膜P型ATPase和潜在的脂质转位酶(或Flippase)， 尤其是在依赖ARF的笼蛋白包裹的囊泡的萌发中。这个 酿酒酵母将用于这项工作，因为 所有偶联的真核细胞分泌途径的基本相似性 利用这种有机体强大的遗传和分子手段 使其成为一个理想的模式系统。这项研究项目的具体目标是 确定是否需要Drs2p来招募ARF和clathrin到高尔基 膜，从而表明Drs2p在笼蛋白包裹的囊泡中起直接作用 萌芽中。此外，还将测试所建议的Drs2p的脂翻转酶活性 Drs2p与四种Drs2p相关蛋白的潜在功能重叠 在酵母基因组中编码的。这对人类有深远的影响 可以从这项研究中获得的健康。Drs2p和clathrin都是 高尔基复合体在运输和运输中的正常功能所必需的 许多蛋白质的加工。此外，与Drs2p相关的脂翻转酶有 认为将磷脂酰丝氨酸(PS)限制在血浆的内叶 薄膜。丧失这种PS在血细胞中的不对称分布可以刺激 凝块的形成和在凋亡细胞中允许识别和吞噬 通过巨噬细胞。

DESCRIPTION (APPLICANT'S ABSTRACT): A striking feature of eukaryotic cells, from yeast to human, is their compartmental organization into membrane-bound organelles, each with a unique composition and function. The long-term goal of this research project is to understand how the Goigi complex, a multi-compartment organelle, performs its essential role in the transport, modification and sorting of proteins in the secretory pathway. Towards this goal, the function of ADP-ribosylation factor (ARF) in vesicle-mediated transport from the Golgi complex is being examined. ARF appears to regulate the budding of both COPI- and clathrin-coated vesicles from the Golgi complex. The proposed studies stem from recent discoveries implicating a role for Drs2p, an integral membrane P-type ATPase and potential lipid translocase (or flippase), specifically in the ARF-dependent budding of clathrin coated vesicles. The yeast Saccharomyces cerevisiae will be used for this work because of the fundamental similarity of the secretory pathway in all eukaryotic cells coupled with the powerful genetic and molecular approaches available with this organism make it an ideal model system. The specific goals of this research project are to determine if Drs2p is required for recruiting ARF and clathrin to Golgi membranes, thus indicating a direct role for Drs2p in clathrin coated vesicle budding. The proposed lipid flippase activity of Drs2p will be tested as will the potential overlap in function between Drs2p and four Drs2p-related proteins encoded within the yeast genome. There are profound implications to human health that can be derived from this study. Both Drs2p and clathrin are required for the normal function of the Golgi complex in the transport and processing of many proteins. In addition, lipid flippases related to Drs2p are thought to restrict phosphatidylserine (PS) to the inner leaflet of 'the plasma membrane. Loss of this asymmetric distribution of PS in blood cells stimulates clot formation and in apoptotic cells allows for recognition and phagocytosis by macrophages.