Despite a conserved set of core mitochondrial functions, animal mitochondrial proteomes show a large variation in size. In this study, we analyzed the putative mechanisms behind and functional significance of this variation by performing comparative analysis of the experimentally-verified mitochondrial proteomes of four bilaterian animals (human, mouse, Caenorhabditis elegans, and Drosophila melanogaster and two non-animal outgroups (Acanthamoeba castellanii and Saccharomyces cerevisiae). We found that, of several factors affecting mitochondrial proteome size, evolution of novel mitochondrial proteins in mammals and loss of ancestral proteins in protostomes were the main contributors. Interestingly, the gain and loss of conventional mitochondrial targeting signals was not a significant factor in the proteome size evolution.

中文翻译：

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动物线粒体蛋白质组大小变化的原因和后果

尽管有一组保守的核心线粒体功能，但动物线粒体蛋白质组的大小差异很大。在这项研究中，我们通过对四种双侧动物（人类、小鼠、秀丽隐杆线虫、黑腹果蝇和两个非动物外群（棘阿米巴）的实验验证的线粒体蛋白质组进行比较分析，分析了这种变异背后的推定机制和功能意义。 castellanii 和 Saccharomyces cerevisiae。我们发现，在影响线粒体蛋白质组大小的几个因素中，哺乳动物中新型线粒体蛋白的进化和原虫中祖先蛋白的丢失是主要的贡献者。有趣的是，传统线粒体靶向信号的获得和损失并不是蛋白质组大小演变的一个重要因素。