title: The ND2 subunit is labeled by a photoaffinity analogue of asimicin, a potent complex I inhibitor.
abstract: NADH:ubiquinone oxidoreductase (complex I) is the entry enzyme of mitochondrial oxidative phosphorylation. To obtain the structural information on inhibitor/quinone binding sites, we synthesized [3H]benzophenone-asimicin ([3H]BPA), a photoaffinity analogue of asimicin, which belongs to the acetogenin family known as the most potent complex I inhibitor. We found that [3H]BPA was photo-crosslinked to ND2, ND1 and ND5 subunits, by the three dimensional separation (blue-native/doubled SDS-PAGE) of [3H]BPA-treated bovine heart submitochondrial particles. The cross-linking was blocked by rotenone. This is the first finding that ND2 was photo-crosslinked with a potent complex I inhibitor, suggesting its involvement in the inhibitor/quinone-binding.
authors.affiliation: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA. eikoo@mail.med.upenn.edu
authors.forename: Eiko
authors.initials: E
authors.lastname: Nakamaru-Ogiso
authors.forename: Hongna
authors.initials: H
authors.lastname: Han
authors.forename: Akemi
authors.initials: A
authors.lastname: Matsuno-Yagi
authors.forename: Ehud
authors.initials: E
authors.lastname: Keinan
authors.forename: Subhash C
authors.initials: SC
authors.lastname: Sinha
authors.forename: Takao
authors.initials: T
authors.lastname: Yagi
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ohnishi
mesh_terms: D000818:Animals; D001577:Benzophenones / Q000737:chemistry*; D002417:Cattle; D042967:Electron Transport Complex I / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry*; D005663:Furans / Q000737:chemistry*; D015151:Immunoblotting; D009097:Multienzyme Complexes / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D021122:Protein Subunits; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001577:Benzophenones; D004791:Enzyme Inhibitors; D005663:Furans; D009097:Multienzyme Complexes; D021122:Protein Subunits; C061022:bullatacin; C047723:benzophenone; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D042967:Electron Transport Complex I