Kuhn Andreas, Haase Maximilian, Leptihn Sebastian
Institute of Microbiology and Molecular Biology, University of Hohenheim, Stuttgart, Germany.
Institute of Microbiology and Molecular Biology, University of Hohenheim, Stuttgart, Germany.
Biophys J. 2017 Sep 19;113(6):1187-1193. doi: 10.1016/j.bpj.2017.03.027. Epub 2017 Apr 25.
The insertion of newly synthesized membrane proteins is a well-regulated and fascinating process occurring in every living cell. Several translocases and insertases have been found in prokaryotic and eukaryotic cells, the Sec61 complex and the Get complex in the endoplasmic reticulum and the SecYEG complex and YidC in bacteria and archaea. In mitochondria, TOM and TIM complexes transport nuclear-encoded proteins, whereas the Oxa1 is required for the insertion of mitochondria-encoded membrane proteins. Related to the bacterial YidC and the mitochondrial Oxa1 are the Alb3 and Alb4 proteins in chloroplasts. These membrane insertases are comparably simple and can be studied in vitro, after their biochemical purification and reconstitution in artificial lipid bilayers such as liposomes or nanodiscs. Here, we describe the recent progress to study the molecular mechanism of YidC-dependent and unassisted membrane insertion at the single molecule level.
新合成膜蛋白的插入是每个活细胞中都发生的一个受到良好调控且引人入胜的过程。在原核细胞和真核细胞中已发现几种转位酶和插入酶，在内质网中有Sec61复合物和Get复合物，在细菌和古细菌中有SecYEG复合物和YidC。在线粒体中，TOM和TIM复合物转运核编码蛋白，而Oxa1是线粒体编码膜蛋白插入所必需的。与细菌YidC和线粒体Oxa1相关的是叶绿体中的Alb3和Alb4蛋白。这些膜插入酶相对简单，在经过生化纯化并在脂质体或纳米盘等人工脂质双层中重建后，可以在体外进行研究。在这里，我们描述了在单分子水平上研究YidC依赖性和非依赖性膜插入分子机制的最新进展。
