The Saccharomyces cerevisiae respiratory supercomplex factor 2 (Rcf2) is a 224-residue protein located in the mitochondrial inner membrane where it is involved in the formation of supercomplexes composed of cytochrome bc₁ and cytochrome c oxidase. We previously demonstrated that Rcf2 forms a dimer in dodecylphosphocholine micelles, and here we report the solution NMR structure of this Rcf2 dimer. Each Rcf2 monomer has two soluble α helices and five putative transmembrane (TM) α helices, including an unexpectedly charged TM helix at the C terminus, which mediates dimer formation. The NOE contacts indicate the presence of inter-monomer salt bridges and hydrogen bonds at the dimer interface, which stabilize the Rcf2 dimer structure. Moreover, NMR chemical shift change mapping upon lipid titrations as well as molecular dynamics analysis reveal possible structural changes upon embedding Rcf2 into a native lipid environment. Our results contribute to the understanding of respiratory supercomplex formation and regulation.

的酿酒酵母呼吸道超复合因子2（RCF2）是位于哪里它参与细胞色素组成supercomplexes形成线粒体内膜224个残基的蛋白质BC ₁和细胞色素C ^氧化酶。我们之前证明了 Rcf2 在十二烷基磷酸胆碱胶束中形成二聚体，在这里我们报告了该 Rcf2 二聚体的溶液 NMR 结构。每个 Rcf2 单体都有两个可溶性 α 螺旋和五个假定的跨膜 (TM) α 螺旋，包括在 C 末端意外带电的 TM 螺旋，它介导二聚体的形成。NOE 接触表明二聚体界面处存在单体间盐桥和氢键，它们稳定了 Rcf2 二聚体结构。此外，脂质滴定的 NMR 化学位移变化图以及分子动力学分析揭示了将 Rcf2 嵌入天然脂质环境后可能的结构变化。我们的结果有助于理解呼吸超复合体的形成和调节。