MOLECULAR GENETICS OF INTRACELLULAR PROTEIN TRANSPORT

真核细胞组装和生长的一个基本方面是 将新合成的蛋白质从细胞质运输到一种 化学上不同的亚细胞室的数量。《秘社》 途径，细胞内蛋白质运输的一条重要途径，提供 可溶的和膜结合的蛋白质都能到达细胞表面。每一步都是 这种运输过程是由携带货物的小泡介导的，这些小泡来自 隔膜一个隔室的膜并与另一个隔室的膜融合这个 酿酒酵母具有与酿酒酵母相似的分泌途径。 哺乳动物细胞。驱动这一过程的一类重要基因(SEC) 囊泡蛋白运输的研究已经通过使用 破坏分泌过程的突变体。关于具体的情况，我们知之甚少 这些基因中的大多数都有功能。凯泽博士建议开发一种新的 通过测定SEC基因产物的功能来研究其功能 精确的细胞内定位。巴斯德毕赤酵母与S. 酿酒酵母在许多方面，除了巴斯德酵母细胞含有显著的 和形态上定义明确的高尔基复合体。将制定方法 巴斯德毕赤酵母SEC基因同源物的分离及定位 用抗体染色和电子显微镜观察其产物在巴氏杆菌细胞中的表达 显微镜。此外，Kaiser博士将开发基因筛查来 识别新的SEC基因。这些新基因的产物也将是 本地化于巴斯德毕赤酵母。最后，通过使用显性负突变 SEC基因，一种表达不同物种分泌缺陷的通用方法 将对细胞类型进行测试。此方法将对以下情况特别有用 研究二倍体生物体中分泌基因的功能。 酵母Will中蛋白质转运的分子机制研究 直接有助于我们理解 人类细胞，因此，可能会加速治疗的发展 由利用分泌途径退出的病毒引起的疾病 被感染的细胞。此外，这项工作中发现的一些基因可能 对真菌的分泌途径具有特异性，并可提供选择性 针对真菌病原体的治疗目标。

A fundamental aspect of eukaryotic cell assembly and growth is the transport of newly synthesized proteins from the cytoplasm to one of a number of chemically distinct subcellular compartments. The secretory pathway, a prominent route of intracellular protein transport, delivers both soluble and membrane-bound proteins to the cell surface. Each step in this transport process is mediated by cargo-carrying vesicles that bud from the membrane of one compartment and fuse with the membrane of the next. The yeast Saccharomyces cerevisiae has a secretory pathway much like that of mammalian cells. An important class of genes (SEC) that drive the process of vesicular protein transport have been identified through the use of mutants that disrupt the secretory process. Little is known of the precise function of most of these genes. Dr. Kaiser proposes to develop a new method to study the function of SEC gene products by determining their precise intracellular location. The yeast Pichia pastoris is similar to S. cerevisiae in many respects except that P. pastoris cells contain prominent and morphologically well defined Golgi complexes. Methods will be devised for the isolation of P. pastoris homologs of SEC genes and the localization of their products in P. pastoris cells by antibody staining and electron microscopy. In addition, Dr. Kaiser will develop genetic screens to identify new SEC genes. The products of these new genes will also be localized in P. pastoris. Finally, by using dominant negative mutations in SEC genes, a general method for expressing secretory defects in different cell types will be tested. This method will be particularly useful for studying the function of secretory genes in diploid organisms. Elucidation of the molecular mechanism of protein transport in yeast will directly contribute to our understanding of the equivalent processes in human cells and may, therefore, speed the development of therapies for diseases caused by those viruses that use the secretory pathway to exit infected cells. In addition, some of the genes identified in this work may be particular to fungal secretory pathway and could provide selective targets for therapy against fungal pathogens.