The reducible complexity of a mitochondrial molecular machine
The reducible complexity of a mitochondrial molecular machine
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DOI：
10.1073/pnas.0908264106
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发表时间：
2009-09-15
影响因子：
11.1
通讯作者：
Lithgow, Trevor
中科院分区：
文献类型：
--
作者：
Clements, Abigail;Bursac, Dejan;Lithgow, Trevor
分子机器驱动基本的生物过程，这些机器的每个组成部分都贡献了部分功能或结构元素。线粒体是真核细胞的细胞器，其生物发生依赖于一套蛋白质运输的分子机器。这些分子机器是如何进化的是一个基本问题。线粒体来源于α-蛋白细菌内共生体，我们在α-蛋白细菌中鉴定出线粒体蛋白运输机的组成部分。在细菌中，这些成分位于内膜，在拓扑上等同于线粒体蛋白质。尽管细菌蛋白质在简单的组装中发挥作用，但将它们转化为蛋白质运输机需要相对较少的突变。这种对蛋白质运输的分析为细胞机械的总体进化提供了蓝图。
Molecular machines drive essential biological processes, with the component parts of these machines each contributing a partial function or structural element. Mitochondria are organelles of eukaryotic cells, and depend for their biogenesis on a set of molecular machines for protein transport. How these molecular machines evolved is a fundamental question. Mitochondria were derived from an alpha-proteobacterial endosymbiont, and we identified in alpha-proteobacteria the component parts of a mitochondrial protein transport machine. In bacteria, the components are found in the inner membrane, topologically equivalent to the mitochondrial proteins. Although the bacterial proteins function in simple assemblies, relatively little mutation would be required to convert them to function as a protein transport machine. This analysis of protein transport provides a blueprint for the evolution of cellular machinery in general.