Zíková Alena, Panigrahi Aswini K, Dalley Rachel A, Acestor Nathalie, Anupama Atashi, Ogata Yuko, Myler Peter J, Stuart Kenneth
Seattle Biomedical Research Institute, Seattle, Washington 98109, USA.
Mol Cell Proteomics. 2008 Jul;7(7):1286-96. doi: 10.1074/mcp.M700490-MCP200. Epub 2008 Mar 24.
Although eukaryotic mitochondrial (mt) ribosomes evolved from a putative prokaryotic ancestor their compositions vary considerably among organisms. We determined the protein composition of tandem affinity-purified Trypanosoma brucei mt ribosomes by mass spectrometry and identified 133 proteins of which 77 were associated with the large subunit and 56 were associated with the small subunit. Comparisons with bacterial and mammalian mt ribosomal proteins identified T. brucei mt homologs of L2-4, L7/12, L9, L11, L13-17, L20-24, L27-30, L33, L38, L43, L46, L47, L49, L52, S5, S6, S8, S9, S11, S15-18, S29, and S34, although the degree of conservation varied widely. Sequence characteristics of some of the component proteins indicated apparent functions in rRNA modification and processing, protein assembly, and mitochondrial metabolism implying possible additional roles for these proteins. Nevertheless most of the identified proteins have no homology outside Kinetoplastida implying very low conservation and/or a divergent function in kinetoplastid mitochondria.
尽管真核生物的线粒体（mt）核糖体是从假定的原核祖先进化而来，但其组成在不同生物之间差异很大。我们通过质谱法确定了串联亲和纯化的布氏锥虫mt核糖体的蛋白质组成，并鉴定出133种蛋白质，其中77种与大亚基相关，56种与小亚基相关。与细菌和哺乳动物的mt核糖体蛋白质进行比较，确定了布氏锥虫mt中L2 - 4、L7/12、L9、L11、L13 - 17、L20 - 24、L27 - 30、L33、L38、L43、L46、L47、L49、L52、S5、S6、S8、S9、S11、S15 - 18、S29和S34的同源物，尽管保守程度差异很大。一些组成蛋白的序列特征表明它们在rRNA修饰和加工、蛋白质组装以及线粒体代谢中具有明显功能，这意味着这些蛋白质可能具有其他作用。然而，大多数鉴定出的蛋白质在动质体目之外没有同源性，这意味着它们在动质体线粒体中的保守性非常低和/或功能不同。
