PROTEIN TRANSPORT INTO MAMMALIAN ENDOPLASMIC RETICULUM

这个项目的长期目标是了解分子机制。 通过它将蛋白质运送到哺乳动物体内或插入哺乳动物体内 内质网(ER)膜。我们最近建立了一个系统 重现转位过程的重组蛋白脂质体 用纯化的膜蛋白和纯磷脂。最低要求 内质网细胞膜转位装置似乎只由 Sec61P-三个亚基的复合体和TRAM蛋白。我们现在建议 从这些方面深入分析易位的机制 单个组件。具体地说，我们将使用交联和 解决以下问题的重组方法：1.什么是重组 分子水平上的转位步骤？2.有什么功能？ Sec61P-复合体？3.TRAM蛋白如何促进易位？ 我们还将搜索可能需要的其他组件 翻译后的易位模式，以实现易位的循环 并对转运过程进行调控。 我们相信，我们的研究将对 了解大型生物合成的第一步和决定性步骤 一类蛋白质，包括分泌蛋白质、血浆蛋白质 膜、溶酶体和分泌途径的所有细胞器。

The long-term goal of this project is to understand the molecular mechanism by which proteins are transported across or are inserted into the mammalian endoplasmic reticulum (ER) membrane. We have recently established a system of reconstituted proteoliposomes which reproduces the translocation process with purified membrane proteins and pure phospholipids. The minimum translocation apparatus of the ER membrane seems to comprise only the Sec61p- complex of three subunits and the TRAM protein. We now propose to thoroughly analyze the mechanism of translocation, in terms of these individual components. Specifically, we will use crosslinking and reconstitution methods to address the following questions: 1. What are the steps of translocation on a molecular level? 2. What are the functions of the Sec61p- complex? 3. How does the TRAM protein facilitate translocation? We will also search for additional components which may be required for the postranslational mode of translocation, for the recycling of translocation components and for the regulation of the translocation process. We believe that our studies will contribute significantly to the understanding of the first and decisive step in the biosynthesis of a large class of proteins which includes secretory proteins, proteins of the plasma membrane, of lysosomes and of all organelles of the secretory pathway.