Wichmann H, Hengst L, Gallwitz D
Max Planck Institute for Biophysical Chemistry, Department of Molecular Genetics, Germany.
Cell. 1992 Dec 24;71(7):1131-42. doi: 10.1016/s0092-8674(05)80062-5.
From the budding yeast S. cerevisiae, we have cloned a gene, YPT7, that encodes a GTP-binding protein belonging to the Ypt family of ras-related proteins. The 208 amino acid protein shares identical effector domain and C-terminal sequences with the mammalian Rab7 protein. YPT7 gene disruption did not impair cellular growth at temperatures ranging from 17 degrees C to 37 degrees C. ypt7 null mutants are characterized by highly fragmented vacuoles and differential defects of vacuolar protein transport and maturation. The uptake of alpha factor pheromone by wild-type and Ypt7p-deficient cells was found to be indistinguishable, but in mutant cells lacking Ypt7p, degradation of the endocytosed pheromone was severely inhibited. Our findings suggest a role of Ypt7p in protein transport between endosome-like compartments.
我们从出芽酵母酿酒酵母中克隆了一个基因YPT7，它编码一种属于与ras相关蛋白的Ypt家族的GTP结合蛋白。这种由208个氨基酸组成的蛋白质与哺乳动物的Rab7蛋白具有相同的效应结构域和C末端序列。YPT7基因的破坏在17摄氏度至37摄氏度的温度范围内不会损害细胞生长。ypt7缺失突变体的特征是液泡高度碎片化以及液泡蛋白运输和成熟存在差异缺陷。野生型细胞和缺乏Ypt7p的细胞对α因子信息素的摄取没有区别，但在缺乏Ypt7p的突变细胞中，内吞信息素的降解受到严重抑制。我们的研究结果表明Ypt7p在内体样区室之间的蛋白质运输中发挥作用。
