An essential role of Sam50 in the protein sorting and assembly machinery of the mitochondrial outer membrane
An essential role of Sam50 in the protein sorting and assembly machinery of the mitochondrial outer membrane
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DOI：
10.1074/jbc.c300442200
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发表时间：
2003-12-05
影响因子：
4.8
通讯作者：
Pfanner, N
中科院分区：
文献类型：
--
作者：
Kozjak, V;Wiedemann, N;Pfanner, N
线粒体外膜的蛋白前转位酶（TOM复合体）包含一个重要的亚基，即通道Tom40。Tom40前体的组装途径包括TOM复合体和具有非必需亚基Mas37的分选和组装机制（SAM复合体）。我们已经确定了Sam50，线粒体外膜的第二种必需蛋白质。Sam50含有从细菌到人类保守的β -桶结构域，是SAM复合体的一个亚基。酵母突变体Sam50在Tom40的组装途径和丰富的外膜蛋白孔蛋白上存在缺陷，而基质蛋白的输入不受影响。因此，线粒体外膜的蛋白质分类和组装机制涉及一种必需的、保守的蛋白质。
The preprotein translocase of the outer mitochondrial membrane ( TOM complex) contains one essential subunit, the channel Tom40. The assembly pathway of the precursor of Tom40 involves the TOM complex and the sorting and assembly machinery (SAM complex) with the non-essential subunit Mas37. We have identified Sam50, the second essential protein of the mitochondrial outer membrane. Sam50 contains a beta-barrel domain conserved from bacteria to man and is a subunit of the SAM complex. Yeast mutants of Sam50 are defective in the assembly pathways of Tom40 and the abundant outer membrane protein porin, while the import of matrix proteins is not affected. Thus the protein sorting and assembly machinery of the mitochondrial outer membrane involves an essential, conserved protein.