Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany.
Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany.
Curr Genet. 2019 Aug;65(4):899-903. doi: 10.1007/s00294-019-00965-z. Epub 2019 Apr 3.
In this report, we summarize recent findings about a role of the outer membrane metabolite channel VDAC/porin in protein import into mitochondria. Mitochondria fulfill key functions for cellular energy metabolism. Their biogenesis involves the import of about 1000 different proteins that are produced as precursors on cytosolic ribosomes. The translocase of the outer membrane (TOM complex) forms the entry gate for mitochondrial precursor proteins. Dedicated protein translocases sort the preproteins into the different mitochondrial subcompartments. While protein transport pathways are analyzed to some detail, only little is known about regulatory mechanisms that fine-tune protein import upon metabolic signaling. Recently, a dual role of the voltage-dependent anion channel (VDAC), also termed porin, in mitochondrial protein biogenesis was reported. First, VDAC/porin promotes as a coupling factor import of carrier proteins into the inner membrane. Second, VDAC/porin regulates the formation of the TOM complex. Thus, the major metabolite channel in the outer membrane VDAC/porin connects protein import to mitochondrial metabolism.
在本报告中，我们总结了关于外膜代谢物通道 VDAC/porin 在蛋白质导入线粒体中的作用的最新发现。线粒体履行细胞能量代谢的关键功能。它们的生物发生涉及约 1000 种不同蛋白质的导入，这些蛋白质作为细胞质核糖体上的前体产生。外膜转位酶（TOM 复合物）形成线粒体前体蛋白的进入门。专门的蛋白质转位酶将前体蛋白分拣到不同的线粒体亚区室中。虽然对蛋白质转运途径进行了一些详细的分析，但对于微调代谢信号时蛋白质导入的调节机制知之甚少。最近，报道了电压依赖性阴离子通道（VDAC），也称为孔蛋白，在线粒体蛋白生物发生中的双重作用。首先，VDAC/porin 作为偶联因子促进载体蛋白向内膜的导入。其次，VDAC/porin 调节 TOM 复合物的形成。因此，外膜 VDAC/porin 中的主要代谢物通道将蛋白质导入与线粒体代谢联系起来。
