ANALYSIS OF GOLGI MEMBRANE PROTEIN LOCALIZATION IN YEAST

分泌物和细胞质中蛋白质的分类和定位 将使用定位的模型系统来研究内体通路 蛋白质在酿酒酵母TGN中的表达。PI的工作模式提出了两个 两种将蛋白质定位到TGN的独立机制：选择性 从前房室取出并降低转运出的速率 去TGN。初步数据表明，提取涉及相互作用 货运蛋白与Vps35p，一种泡前外周膜蛋白，以及这 假说将在基因抑制者方法中进行检验，以及在 生化结合分析。缓慢退出TGN的建议涉及 驻留的TGN蛋白的胞浆结构域的磷酸化，这将是 使用生化方法进行调查以确定特定的位置 磷酸化后的特定位点突变来改变这些 磷酸化位点。最后，在遗传基因中发现了几个基因。 筛选出高尔基体蛋白质保留有缺陷，其中四个将是 更详细地调查了：grd20、grd21、grd22和grd23。

The sorting and localization of proteins in the secretory and endosomal pathways will be investigated, using the model system of localization of proteins to the TGN in S. cerevisiae. The PI's working model proposes two independent mechanisms that both act to localize proteins to the TGN: selective retrieval from the prevacuolar compartment and a reduced rate of transport out to the TGN. Preliminary data suggest that retrieval involves the interaction of cargo proteins with Vps35p, a prevacuolar peripheral membrane protein, and this hypothesis will be tested in a genetic suppressor approach, as well as in biochemical binding assays. Slow exit from the TGN is proposed to involve the phosphorylation of cytosolic domains of resident TGN proteins, and this will be investigated using biochemical approaches to identify the specific sites of phosphorylation followed by specific site mutagenesis to alter these phosphorylation sites. Finally, several genes have been identified in genetic screens as defective in Golgi retention of proteins, and four of these will be investigated in further detail: grd20, grd21, grd22 and grd23.