Isolation and characterization of SYS genes from yeast, multicopy suppressors of the functional loss of the transport GTPase Ypt6p.
Isolation and characterization of SYS genes from yeast, multicopy suppressors of the functional loss of the transport GTPase Ypt6p.
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发表时间：
1996-10
影响因子：
4
通讯作者：
M. Tsukada;D. Gallwitz
中科院分区：
文献类型：
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作者：
M. Tsukada;D. Gallwitz
在酿酒酵母中，YPT 6基因编码在高尔基体中发现的哺乳动物Rab 6蛋白的同源物。酵母中YPT 6的缺失产生了一种表现为温度敏感性生长和液泡酶羧肽酶Y部分错误分选的表型。为了鉴定可能：（1）与Ypt 6p相互作用的蛋白质;或（2）在相同途径中起作用的蛋白质，我们分离了四个多拷贝抑制子，命名为SYS 1，SYS 2，SYS 3和SYS 5，它们可以补充ypt 6无效突变体的温度敏感性生长表型。在高表达，这些基因也能够部分抑制羧肽酶Y的错配在一个多拷贝质粒上的SYS 2抑制除了温度敏感表型的sec 7 -1，一个突变体之间的运输缺陷，并从高尔基室。SYS 1和SYS 2的基因破坏没有导致显著的生长缺陷。然而，在ypt 6无效突变体中SYS 1和/或SYS 2的缺失增强了液泡蛋白分选和细胞生长中的缺陷。而蛋白质的分泌没有显着影响，在这些突变体中，α-因子前体的Kex 2蛋白酶的加工被抑制，这表明YPT 6和它的无效突变体抑制剂之间的运输后期高尔基体和prevacuolar，内体样隔间的功能。
In Saccharomyces cerevisiae, the YPT6 gene encodes the homologue of the mammalian Rab6 protein found in the Golgi apparatus. Deletion of YPT6 in yeast produces a phenotype showing temperature-sensitive growth and partial missorting of the vacuolar enzyme, carboxypeptidase Y. To identify proteins that might: (1) interact with Ypt6p; or (2) act in the same pathway, we have isolated four multicopy suppressors, named SYS1, SYS2, SYS3 and SYS5, that can complement the temperature-sensitive growth phenotype of the ypt6 null mutant. On high expression, these genes are also able to partially suppress the missorting of carboxypeptidase Y.SYS2 on a multicopy plasmid suppresses in addition the temperature-sensitive phenotype of sec7-1, a mutant defective in transport between and from the Golgi compartment. Gene disruption of SYS1 and SYS2 did not result in significant growth defects. However, deletion of SYS1 and/or SYS2 in the ypt6 null mutant enhances defects in vacuolar protein sorting and in cell growth. Whereas protein secretion was not significantly affected in these mutants, the processing of alpha-factor precursor by the Kex2 protease was inhibited, suggesting a function of YPT6 and its null mutant suppressors in transport between the late Golgi and a prevacuolar, endosome-like compartment.