Membrane translocation of mitochondrially coded Cox2p: Distinct requirements for export of N and C termini and dependence on the conserved protein Oxa1p
Membrane translocation of mitochondrially coded Cox2p: Distinct requirements for export of N and C termini and dependence on the conserved protein Oxa1p
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DOI：
10.1091/mbc.8.8.1449
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发表时间：
1997-08-01
影响因子：
3.3
通讯作者：
Fox, TD
中科院分区：
文献类型：
--
作者：
He, SC;Fox, TD
为了在体内研究细胞合成的蛋白质从基质到膜间隙的输出，我们将合成的线粒体基因AXG 8“”与线粒体DNA中的酿酒酵母COX 2基因融合。Arg 8（m）p部分通过内膜易位，当通过依赖于至少部分包含在输出的Cox 2 p C-末端尾部内的拓扑信息的机制融合到Cox 2 p C-末端时。前Cox 2 p前导肽不发出易位信号。Cox 2 p C-末端尾的输出，而不是N-末端尾的输出，依赖于内膜电位。线粒体输出系统并不十分类似于细菌的Sec易位酶。然而，在缺乏广泛保守的内膜蛋白Oxa 1 p的细胞中，Cox 2 p的两个出口结构域的正常易位是有缺陷的。
To study in vivo the export of mitochondrially synthesized protein from the matrix to the intermembrane space, we have fused a synthetic mitochondrial gene, AXG8''', to the Saccharomyces cerevisiae COX2 gene in mitochondrial DNA. The Arg8(m)p moiety was translocated through the inner membrane when fused to the Cox2p C terminus by a mechanism dependent on topogenic information at least partially contained within the exported Cox2p C-terminal tail. The pre-Cox2p leader peptide did not signal translocation. Export of the Cox2p C-terminal tail, but not the N-terminal tail, was dependent on the inner membrane potential. The mitochondrial export system does not closely resemble the bacterial Sec translocase. However, normal translocation of both exported domains of Cox2p was defective in cells lacking the widely conserved inner membrane protein Oxa1p.