Analysis of the mitochondrial proteome of cybrid cells harbouring a truncative mitochondrial DNA mutation in respiratory complex I.
Mol Biosyst
; 10(6): 1313-9, 2014 Jun.
Article
em En
| MEDLINE
| ID: mdl-24643264
ABSTRACT
Transmitochondrial cytoplasmic hybrids (cybrids) are well established model systems to reveal the effects of mitochondrial DNA (mtDNA) mutations on cell metabolism excluding the interferences of a different nuclear background. The m.3571insC mutation in the MTND1 gene of respiratory complex I (CI) is commonly detected in oncocytic tumors, in which it causes a severe CI dysfunction leading to an energetic impairment when present above 83% mutant load. To assess whether the energetic deficit may alter the mitochondrial proteome, OS-78 and OS-93 cybrid cell lines bearing two different degrees of the m.3571insC mutation (78% and 92.8%, respectively) and control cybrids bearing wild-type mtDNA (CC) were analyzed. Two-dimensional electrophoresis and mass spectrometry revealed significant alterations only in cybrids above the threshold (OS-93). All differentially expressed proteins are decreased. In particular, the levels of the pyruvate dehydrogenase E1 chain B subunit (E1ß), of lipoamide dehydrogenase (E3), the enzyme component of pyruvate and 2-oxoglutarate dehydrogenase complexes, and of lactate dehydrogenase B (LDHB) were reduced. Moreover, a significant decrease of the pyruvate dehydrogenase complex activity was found when OS-93 cybrid cells were grown in galactose medium, a metabolic condition that forces cells to use respiration. These results demonstrate that the energetic impairment caused by the almost homoplasmic m.3571insC mutation perturbs cellular metabolism leading to a decreased steady state level of components of very important mitochondrial NAD-dependent dehydrogenases.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Regulação da Expressão Gênica
/
Proteoma
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Mitocôndrias
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NADH Desidrogenase
Limite:
Humans
Idioma:
En
Revista:
Mol Biosyst
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Itália