线粒体呼吸链复合物（复合物I，II，III和IV）一直都是国内外研究的热点领域之一。各复合物之间灵活多样地组合成超复合物是近年来呼吸链研究的一大突破——新的超复合物的发现对于阐明呼吸链电子传递机制、开发针对呼吸链复合物的新型杀菌剂等都具有重要意义。尽管有少数研究表明复合物II与III可能存在相互作用，但具体的作用机制和超复合物结构至今尚不清楚。本项目以前期发现的特异作用于琥珀酸细胞色素c氧化还原酶（复合物II、III的混合酶）的化合物为契机，提出引入小分子探针作为稳定剂或交联剂，综合多学科前沿技术，探究复合物II与III的相互作用机制，揭示由复合物II与III组成的超复合物的三维结构。本项目的开展既有助于深入理解呼吸链的电子传递机制，也将为杀菌剂的创制提供新的作用机制，尤其为解决目前靶向复合物II和复合物III的杀菌剂所面临的严重抗性问题提供有效途径。

The mitochondrial respiratory chain complexes (complexes I, II, III and IV) have always been the hotspots of scientific research. Discovery of respiratory supercomplexes in recent years, as a milestone of this area, may be a potent accelerator for elucidating the mechanism of electronic transfer of respiratory chain as well as for developing new fungicides targeting respiratory complexes. It is notable that, although a few reports proposed the possible interaction between complex II and complex III, none of structural report of complex II-included supercomplex has been found. Inspired by the discovery of the specific probe targeting the succinic acid cytochrome c redox enzyme (mixture of complexes II and III, referred to as SCR), we assume that, by introducing the chemical probes as stabilizers or crosslinking agents, either to stabilize the supercomplex II - III or to covalently couple the complex II and complex III, the structural basis of the interface between complex II and complex III would be disclosed. In all, this project aims to combine multi-disciplinary cutting-edge technologies such as comprehensive chemical biology, biochemistry and structural biology, to explore the interaction mechanism between complex II and complex III. The launch of this project will not only contribute to an in-depth understanding of the electronic transmission mechanism of the respiratory chain, but also provide a novel strategy for fungicides discovery, in particular to offer a clue for solving the serious resistance problems of fungicides targeting complex II and compound III.