Alterations of the mitochondrial proteome caused by the absence of mitochondrial DNA: A proteomic view.
The proper functioning of mitochondria requires that both the mitochondrial and the nuclear genome are functional. To investigate the importance of the mitochondrial genome, which encodes only 13 subunits of the respiratory complexes, the mitochondrial rRNAs and a few tRNAs, we performed a comparative study on the 143B cell line and on its Rho-0 counterpart, i.e., devoid of mitochondrial DNA. Quantitative differences were found, of course in the respiratory complexes subunits, but also in the mitochondrial translation apparatus, mainly mitochondrial ribosomal proteins, and in the ion and protein import system, i.e., including membrane proteins. Various mitochondrial metabolic processes were also altered, especially electron transfer proteins and some dehydrogenases, but quite often on a few proteins for each pathway. This study also showed variations in some hypothetical or poorly characterized proteins, suggesting a mitochondrial localization for these proteins. Examples include a stomatin-like protein and a protein sharing homologies with bacterial proteins implicated in tyrosine catabolism. Proteins involved in apoptosis control are also found modulated in Rho-0 mitochondria.
CEA, Laboratoire d'Immunochimie, DRDC/ICH, INSERM U 548, CEA-Grenoble, Grenoble, France.
Mireille
M
Chevallet
Pierre
P
Lescuyer
Hélène
H
Diemer
Alain
A
van Dorsselaer
Emmanuelle
E
Leize-Wagner
Thierry
T
Rabilloud
D004272:DNA, Mitochondrial / Q000502:physiology*; D045222:Electron Transport Chain Complex Proteins / Q000172:deficiency / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D006801:Humans; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D021381:Protein Transport; D020543:Proteome / Q000737:chemistry* / Q000235:genetics; D040901:Proteomics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014407:Tumor Cells, Cultured
D004272:DNA, Mitochondrial; D045222:Electron Transport Chain Complex Proteins; D024101:Mitochondrial Proteins; D020543:Proteome