Bipartite signals mediate subcellular targeting of tail-anchored membrane proteins in Saccharomyces cerevisiae
Bipartite signals mediate subcellular targeting of tail-anchored membrane proteins in Saccharomyces cerevisiae
复制标题
DOI：
10.1074/jbc.m212725200
复制
发表时间：
2003-03-07
影响因子：
4.8
通讯作者：
Lithgow, T
中科院分区：
文献类型：
--
作者：
Beilharz, T;Egan, B;Lithgow, T
尾锚定蛋白具有通过单个COOH末端跨膜区段锚定至细胞内膜的NH 2末端胞质结构域。序列分析在酿酒酵母中鉴定出55种尾锚定蛋白，其中包括几种新型蛋白，包括Prm 3，我们发现它是核融合所需的，并且尾锚定在核膜中。线粒体外膜中存在总共六种尾锚定蛋白，并且具有充当靶向信号的相对亲水的跨膜区段。其余的，到目前为止，大多数，通过一个二分系统的信号定位：均匀疏水尾锚首先插入内质网，和额外的片段内的胞质结构域的每种蛋白质可以决定随后的分选到一个精确的目的地在细胞内。
Tail-anchored proteins have an NH2-terminal cytosolic domain anchored to intracellular membranes by a single, COOH-terminal, transmembrane segment. Sequence analysis identified 55 tail-anchored proteins in Saccharomyces cerevisiae, with several novel proteins, including Prm3, which we find is required for karyogamy and is tail-anchored in the nuclear envelope. A total of six tail-anchored proteins are present in the mitochondrial outer membrane and have relatively hydrophilic transmembrane segments that serve as targeting signals. The rest, by far the majority, localize via a bipartite system of signals: uniformly hydrophobic tail anchors are first inserted into the endoplasmic reticulum, and additional segments within the cytosolic domain of each protein can dictate subsequent sorting to a precise destination within the cell.