Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto, Japan; Institute for Protein Research, Osaka University, Suita, Japan
Atsuko Nakanishi
Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto, Japan; Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Research Center for Ultra-High Voltage Electron Microscopy, Mihogaoka, Osaka, Japan
Aya Furuta
Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto, Japan
Takayuki Kato
Institute for Protein Research, Osaka University, Suita, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
Keiichi Namba
Graduate School of Frontier Biosciences, Osaka University, Suita, Japan; RIKEN Center for Biosystems Dynamics Research and SPring-8 Center, Suita, Japan; JEOL YOKOGUSHI Research Alliance Laboratories, Osaka University, Suita, Japan
Masatada Tamakoshi
Department of Molecular Biology, Tokyo University of Pharmacy and Life Sciences, Horinouchi, Hachioji, Tokyo, Japan
Kaoru Mitsuoka
Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Research Center for Ultra-High Voltage Electron Microscopy, Mihogaoka, Osaka, Japan
V-ATPase is an energy converting enzyme, coupling ATP hydrolysis/synthesis in the hydrophilic V1 domain, with proton flow through the Vo membrane domain, via rotation of the central rotor complex relative to the surrounding stator apparatus. Upon dissociation from the V1 domain, the Vo domain of the eukaryotic V-ATPase can adopt a physiologically relevant auto-inhibited form in which proton conductance through the Vo domain is prevented, however the molecular mechanism of this inhibition is not fully understood. Using cryo-electron microscopy, we determined the structure of both the holo V/A-ATPase and isolated Vo at near-atomic resolution, respectively. These structures clarify how the isolated Vo domain adopts the auto-inhibited form and how the holo complex prevents formation of the inhibited Vo form.
