Molecular Bioenergetics Group, Medical School, Cluster of Excellence Frankfurt Macromolecular Complexes, Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
Cell Metab. 2012 Oct 3;16(4):538-49. doi: 10.1016/j.cmet.2012.08.009. Epub 2012 Sep 13.
Macromolecular complexes are essential players in numerous biological processes. They are often large, dynamic, and rather labile; approaches to study them are scarce. Covering masses up to ∼30 MDa, we separated the native complexome of rat heart mitochondria by blue-native and large-pore blue-native gel electrophoresis to analyze its constituents by mass spectrometry. Similarities in migration patterns allowed hierarchical clustering into interaction profiles representing a comprehensive analysis of soluble and membrane-bound complexes of an entire organelle. The power of this bottom-up approach was validated with well-characterized mitochondrial multiprotein complexes. TMEM126B was found to comigrate with known assembly factors of mitochondrial complex I, namely CIA30, Ecsit, and Acad9. We propose terming this complex mitochondrial complex I assembly (MCIA) complex. Furthermore, we demonstrate that TMEM126B is required for assembly of complex I. In summary, complexome profiling is a powerful and unbiased technique allowing the identification of previously overlooked components of large multiprotein complexes.
大分子复合物是许多生物过程中的重要参与者。它们通常很大、动态且相当不稳定；研究它们的方法很少。我们通过蓝色非变性电泳和大孔蓝色非变性电泳分离大鼠心脏线粒体的天然复合物组，通过质谱分析其成分。迁移模式的相似性允许进行层次聚类，形成相互作用图谱，代表整个细胞器可溶性和膜结合复合物的综合分析。这种自下而上的方法的有效性通过具有良好特征的线粒体多蛋白复合物得到了验证。TMEM126B 与已知的线粒体复合物 I 组装因子 CIA30、Ecsit 和 Acad9 一起迁移。我们建议将这个复合物称为线粒体复合物 I 组装（MCIA）复合物。此外，我们证明 TMEM126B 是复合物 I 组装所必需的。总之，复合物组学分析是一种强大且无偏的技术，可用于鉴定大型多蛋白复合物中以前被忽视的成分。
