Chavrier P, Vingron M, Sander C, Simons K, Zerial M
European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Mol Cell Biol. 1990 Dec;10(12):6578-85. doi: 10.1128/mcb.10.12.6578-6585.1990.
Molecular analysis of Saccharomyces cerevisiae secretion mutants has led to the identification of two Ras-like GTP-binding proteins, Ypt1p and Sec4p, which are essential for transport along the exocytic route. To study the regulation of membrane traffic in epithelial cells, a set of 11 clones encoding proteins similar to the YPT1/SEC4 products were isolated from an MDCK (Madin-Darby canine kidney) cell cDNA library. Four of these proteins, Rab8, -9, -10, and -11, are novel members of this subfamily of Ras-like proteins, and two of them are closely related to Ypt1p and Sec4p. The ratio of the number of clones isolated over the total number screened reveals a high level of complexity for this subfamily of GTP-binding proteins. This diversity supports their proposed function in controlling different steps in membrane traffic.
对酿酒酵母分泌突变体的分子分析已导致鉴定出两种类Ras GTP结合蛋白，即Ypt1p和Sec4p，它们对于沿胞吐途径的运输至关重要。为了研究上皮细胞中膜运输的调控，从MDCK（麦迪逊-达比犬肾）细胞cDNA文库中分离出一组11个编码与YPT1/SEC4产物相似蛋白质的克隆。这些蛋白质中的四种，即Rab8、-9、-10和-11，是这类类Ras蛋白亚家族的新成员，其中两种与Ypt1p和Sec4p密切相关。分离出的克隆数与筛选总数的比例揭示了这个GTP结合蛋白亚家族的高度复杂性。这种多样性支持了它们在控制膜运输不同步骤中所提出的功能。
