Department of Cellular Biochemistry, Max Planck Institute of Biochemistry (MPIB), Martinsried, Germany.
EMBO J. 2011 Oct 18;30(21):4356-70. doi: 10.1038/emboj.2011.379.
Mitochondria are organelles with a complex architecture. They are bounded by an envelope consisting of the outer membrane and the inner boundary membrane (IBM). Narrow crista junctions (CJs) link the IBM to the cristae. OMs and IBMs are firmly connected by contact sites (CS). The molecular nature of the CS remained unknown. Using quantitative high-resolution mass spectrometry we identified a novel complex, the mitochondrial contact site (MICOS) complex, formed by a set of mitochondrial membrane proteins that is essential for the formation of CS. MICOS is preferentially located at the CJs. Upon loss of one of the MICOS subunits, CJs disappear completely or are impaired, showing that CJs require the presence of CS to form a superstructure that links the IBM to the cristae. Loss of MICOS subunits results in loss of respiratory competence and altered inheritance of mitochondrial DNA.
线粒体具有复杂的结构，是一种细胞器。它由外膜和内界膜（IBM）组成的包膜所包围。狭窄的嵴间连接（CJs）将 IBM 与嵴连接起来。OMs 和 IBM 由接触位点（CS）牢固地连接。CS 的分子性质仍然未知。使用定量高分辨率质谱，我们鉴定出一种新型的复合物，即线粒体接触位点（MICOS）复合物，由一组线粒体膜蛋白组成，对于 CS 的形成是必不可少的。MICOS 主要位于 CJs 处。当 MICOS 的一个亚基缺失时，CJs 完全消失或受损，表明 CJs 需要 CS 的存在才能形成将 IBM 与嵴连接起来的超结构。MICOS 亚基的缺失会导致呼吸能力丧失和线粒体 DNA 的遗传改变。
