Cork-in-bottle mechanism of inhibitor binding to mammalian complex I.
Chung, I., Serreli, R., Cross, J.B., Di Francesco, M.E., Marszalek, J.R., Hirst, J.(2021) Sci Adv 7
- PubMed: 33990335 
- DOI: https://doi.org/10.1126/sciadv.abg4000
- Primary Citation of Related Structures:  
7B93 - PubMed Abstract: 
Mitochondrial complex I (NADH:ubiquinone oxidoreductase), a major contributor of free energy for oxidative phosphorylation, is increasingly recognized as a promising drug target for ischemia-reperfusion injury, metabolic disorders, and various cancers. Several pharmacologically relevant but structurally unrelated small molecules have been identified as specific complex I inhibitors, but their modes of action remain unclear. Here, we present a 3.0-Å resolution cryo-electron microscopy structure of mammalian complex I inhibited by a derivative of IACS-010759, which is currently in clinical development against cancers reliant on oxidative phosphorylation, revealing its unique cork-in-bottle mechanism of inhibition. We combine structural and kinetic analyses to deconvolute cross-species differences in inhibition and identify the structural motif of a "chain" of aromatic rings as a characteristic that promotes inhibition. Our findings provide insights into the importance of π-stacking residues for inhibitor binding in the long substrate-binding channel in complex I and a guide for future biorational drug design.
Organizational Affiliation: 
MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.