GRIM-19, a cell death regulatory gene product, is a subunit of bovine mitochondrial NADH:ubiquinone oxidoreductase (complex I).
The sequences of 42 subunits of NADH:ubiquinone oxidoreductase (complex I) from bovine heart mitochondria have been described previously. Seven are encoded by mitochondrial DNA, whereas the remaining 35 are nuclear gene products imported into the organelle from the cytoplasm. An additional protein, which does not correspond to any previously known subunit of the complex I assembly, has now been detected. Denaturing gels of subcomplex Ilambda, the hydrophilic arm of complex I, clearly show a hitherto unidentified band, which was digested with trypsin and subjected to mass-spectrometric analysis to provide several peptide sequences, used in cDNA cloning and sequencing. Measurement of the intact protein mass indicated that the N terminus is acetylated. The new complex I subunit (B16.6) is the bovine homolog of GRIM-19, the product of a cell death regulatory gene induced by interferon-beta and retinoic acid, thus providing a new link between the mitochondrion and its electron-transport chain and apoptotic cell death.
Fearnley
I M
IM
Medical Research Council Dunn Human Nutrition Unit, Wellcome Trust/Medical Research Council Building, Hills Road, Cambridge CB2 2XY, United Kingdom.
Carroll
J
J
Shannon
R J
RJ
Runswick
M J
MJ
Walker
J E
JE
Hirst
J
J
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D001483:Base Sequence; D015153:Blotting, Western; D002417:Cattle; D003593:Cytoplasm / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004579:Electron Transport; D042967:Electron Transport Complex I; D004591:Electrophoresis, Polyacrylamide Gel; D016899:Interferon-beta / Q000378:metabolism; D013058:Mass Spectrometry; D008928:Mitochondria / Q000201:enzymology* / Q000378:metabolism; D008969:Molecular Sequence Data; D009206:Myocardium / Q000201:enzymology*; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014212:Tretinoin / Q000378:metabolism; D014357:Trypsin / Q000494:pharmacology
D018076:DNA, Complementary; D014212:Tretinoin; D016899:Interferon-beta; D009247:NADH, NADPH Oxidoreductases; D014357:Trypsin; D042967:Electron Transport Complex I