Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53233, USA.
EMBO Rep. 2011 Sep 1;12(9):950-5. doi: 10.1038/embor.2011.133.
Mitochondrial ribosomal protein 20 (Mrp20) is a component of the yeast mitochondrial large (54S) ribosomal subunit and is homologous to the bacterial L23 protein, located at the ribosomal tunnel exit site. The carboxy-terminal mitochondrial-specific domain of Mrp20 was found to have a crucial role in the assembly of the ribosomes. A new, membrane-bound, ribosomal-assembly subcomplex composed of known tunnel-exit-site proteins, an uncharacterized ribosomal protein, MrpL25, and the mitochondrial peroxiredoxin (Prx), Prx1, accumulates in an mrp20ΔC yeast mutant. Finally, data supporting the idea that the inner mitochondrial membrane acts as a platform for the ribosome assembly process are discussed.
线粒体核糖体蛋白 20（Mrp20）是酵母线粒体大亚基（54S）核糖体的组成部分，与细菌 L23 蛋白同源，位于核糖体隧道出口位点。已发现 Mrp20 的羧基末端线粒体特异性结构域在核糖体组装中具有关键作用。一种由已知的隧道出口位点蛋白、一个未鉴定的核糖体蛋白 MrpL25 和线粒体过氧化物酶（Prx）Prx1 组成的新型膜结合核糖体组装亚复合物在 mrp20ΔC 酵母突变体中积累。最后，讨论了支持线粒体内膜作为核糖体组装过程平台的观点的数据。
