title: VDAC3 gating is activated by suppression of disulfide-bond formation between the N-terminal region and the bottom of the pore.
abstract: The voltage-dependent anion channels (VDACs), VDAC1, VDAC2, and VDAC3, are pore-forming proteins that control metabolite flux between mitochondria and cytoplasm. VDAC1 and VDAC2 have voltage-dependent gating activity, whereas VDAC3 is thought to have weak activity. The aim of this study was to analyze the channel properties of all three human VDAC isoforms and to clarify the channel function of VDAC3. Bacterially expressed recombinant human VDAC proteins were reconstituted into artificial planar lipid bilayers and their gating activities were evaluated. VDAC1 and VDAC2 had typical voltage-dependent gating activity, whereas the gating of VDAC3 was weak, as reported. However, gating of VDAC3 was evoked by dithiothreitol (DTT) and S-nitrosoglutathione (GSNO), which are thought to suppress disulfide-bond formation. Several cysteine mutants of VDAC3 also exhibited typical voltage-gating. Our results indicate that channel gating was induced by reduction of a disulfide-bond linking the N-terminal region to the bottom of the pore. Thus, channel gating of VDAC3 might be controlled by redox sensing under physiological conditions.
authors.affiliation: Sodeoka Live Cell Chemistry Project, ERATO, JST, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Masateru
authors.initials: M
authors.lastname: Okazaki
authors.affiliation: Sodeoka Live Cell Chemistry Project, ERATO, JST, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Katsue
authors.initials: K
authors.lastname: Kurabayashi
authors.affiliation: Sodeoka Live Cell Chemistry Project, ERATO, JST, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Miwako
authors.initials: M
authors.lastname: Asanuma
authors.affiliation: Sodeoka Live Cell Chemistry Project, ERATO, JST, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Saito
authors.affiliation: Sodeoka Live Cell Chemistry Project, ERATO, JST, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Dodo
authors.affiliation: Sodeoka Live Cell Chemistry Project, ERATO, JST, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. Electronic address: sodeoka@riken.jp.
authors.forename: Mikiko
authors.initials: M
authors.lastname: Sodeoka
mesh_terms: D000595:Amino Acid Sequence; D004220:Disulfides / Q000378:metabolism*; D006801:Humans; D015640:Ion Channel Gating; D033681:Mitochondrial Membrane Transport Proteins / Q000737:chemistry / Q000502:physiology*; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000737:chemistry / Q000502:physiology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D050994:Voltage-Dependent Anion Channels / Q000737:chemistry / Q000502:physiology*
chemical_list: D004220:Disulfides; D033681:Mitochondrial Membrane Transport Proteins; D020033:Protein Isoforms; D011994:Recombinant Proteins; C494768:VDAC3 protein, human; D050994:Voltage-Dependent Anion Channels
keywords: Disulfide-bond; Planar lipid bilayer; Recombinant protein; Redox sensing; S-nitrosylation; Voltage-dependent anion channel