Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
Cell Metab. 2012 Mar 7;15(3):348-60. doi: 10.1016/j.cmet.2012.02.006.
The complexes of the electron transport chain associate into large macromolecular assemblies, which are believed to facilitate efficient electron flow. We have identified a conserved mitochondrial protein, named respiratory supercomplex factor 1 (Rcf1-Yml030w), that is required for the normal assembly of respiratory supercomplexes. We demonstrate that Rcf1 stably and independently associates with both Complex III and Complex IV of the electron transport chain. Deletion of the RCF1 gene caused impaired respiration, probably as a result of destabilization of respiratory supercomplexes. Consistent with the hypothetical function of these respiratory assemblies, loss of RCF1 caused elevated mitochondrial oxidative stress and damage. Finally, we show that knockdown of HIG2A, a mammalian homolog of RCF1, causes impaired supercomplex formation. We suggest that Rcf1 is a member of an evolutionarily conserved protein family that acts to promote respiratory supercomplex assembly and activity.
电子传递链的复合物会聚集形成大型大分子组装体，这些组装体被认为有助于高效的电子流动。我们已经鉴定出一种保守的线粒体蛋白，命名为呼吸超级复合物因子 1（Rcf1-Yml030w），它是呼吸超级复合物正常组装所必需的。我们证明 Rcf1 可以稳定且独立地与电子传递链的复合物 III 和复合物 IV 结合。RCF1 基因的缺失导致呼吸作用受损，可能是由于呼吸超级复合物的不稳定性所致。与这些呼吸组装体的假设功能一致，RCF1 的缺失导致线粒体氧化应激和损伤增加。最后，我们表明，RCF1 的哺乳动物同源物 HIG2A 的敲低导致超级复合物形成受损。我们认为 Rcf1 是一个进化保守的蛋白质家族的成员，它的作用是促进呼吸超级复合物的组装和活性。
