Ryan K R, Menold M M, Garrett S, Jensen R E
Department of Cell Biology and Anatomy, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Mol Biol Cell. 1994 May;5(5):529-38. doi: 10.1091/mbc.5.5.529.
MAS6 encodes an essential inner membrane protein required for mitochondrial protein import in the yeast Saccharomyces cerevisiae (Emtage and Jensen, 1993). To identify new inner membrane import components, we isolated a high-copy suppressor (SMS1) of the mas6-1 mutant. SMS1 encodes a 16.5-kDa protein that contains several potential membrane-spanning domains. The Sms1 protein is homologous to the carboxyl-terminal domain of the Mas6 protein. Like Mas6p, Sms1p is located in the mitochondrial inner membrane and is an essential protein. Depletion of Sms1p from cells causes defects in the import of several mitochondrial precursor proteins, suggesting that Sms1p is a new inner membrane import component. Our observations raise the possibility that Sms1p and Mas6p act together to translocate proteins across the inner membrane.
MAS6编码一种酿酒酵母线粒体蛋白导入所必需的内膜蛋白（Emtage和Jensen，1993年）。为了鉴定新的内膜导入成分，我们分离出了mas6-1突变体的一个高拷贝抑制子（SMS1）。SMS1编码一种16.5 kDa的蛋白质，该蛋白质含有几个潜在的跨膜结构域。Sms1蛋白与Mas6蛋白的羧基末端结构域同源。与Mas6p一样，Sms1p位于线粒体内膜，是一种必需蛋白。从细胞中去除Sms1p会导致几种线粒体前体蛋白的导入出现缺陷，这表明Sms1p是一种新的内膜导入成分。我们的观察结果增加了Sms1p和Mas6p共同作用以使蛋白质穿过内膜的可能性。
