Mass spectrometric identification of a novel phosphorylation site in subunit NDUFA10 of bovine mitochondrial complex I.
Mitochondrial Complex I (NADH:ubiquinone oxidoreductase) consists of at least 46 subunits. Phosphorylation of the 42-kDa subunit NDUFA10 was recently reported using a novel phosphoprotein stain [Schulenberg et al. (2003) Analysis of steady-state protein phosphorylation in mitochondria using a novel fluorescent phosphosensor dye. J. Biol. Chem. 278, 27251]. Two smaller Complex I phosphoproteins, ESSS and MWFE, and their sites of modification, have since been determined [Chen et al. (2004) The phosphorylation of subunits of complex I from bovine heart mitochondria. J. Biol. Chem. 279, 26036]. Here we identify the site of phosphorylation in NDUFA10 from bovine heart mitochondria by tandem mass spectrometry. A single phosphopeptide spanning residues 47-60 was identified and confirmed by synthesis to be (47)LITVDGNICSGKpSK(60), establishing serine-59 as the site of phosphorylation.
Schilling
Birgit
B
Buck Institute for Age Research, Novato, CA 94945, USA.
Aggeler
Robert
R
Schulenberg
Birte
B
Murray
James
J
Row
Richard H
RH
Capaldi
Roderick A
RA
Gibson
Bradford W
BW
D000469:Alkaline Phosphatase / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D042967:Electron Transport Complex I / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D010766:Phosphorylation; D021122:Protein Subunits / Q000737:chemistry* / Q000378:metabolism*; D016415:Sequence Alignment; D021241:Spectrometry, Mass, Electrospray Ionization
D021122:Protein Subunits; D000469:Alkaline Phosphatase; D042967:Electron Transport Complex I