Human Molecular Genetics Advance Access originally published online on December 8, 2003
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Human Molecular Genetics, 2004, Vol. 13, No. 3 303-314
DOI: 10.1093/hmg/ddh027
Mitochondrial complex I mutations in Caenorhabditis elegans produce cytochrome c oxidase deficiency, oxidative stress and vitamin-responsive lactic acidosis
Canadian Institutes of Health Research Group in Membrane Protein Research, Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
Received September 10, 2003; Accepted November 25, 2003
Mitochondrial dysfunction, with an estimated incidence of 1 in 10 000 live births, is among the most common genetically determined conditions. Missense mutations in the human NDUFV1 gene, which encodes the 51 kDa active site subunit of the NADHubiquinone oxidoreductase or complex I, can lead to severe neurological disorders. Owing to the rare and often sporadic nature of mitochondrial disorders, the mechanisms of pathogenesis of most mutations remain poorly understood. We have generated transgenic strains of Caenorhabditis elegans that express disease-causing mutations in the nuo-1 gene, the C. elegans homolog of the NDUFV1 gene. The transgenic strains demonstrate hallmark features of complex I dysfunction such as lactic acidosis and decreased NADH-dependent mitochondrial respiration. They are also hypersensitive to exogenous oxidative stress, suggesting that cellular defense mechanisms against reactive oxygen species are already taxed by an endogenous stress. The lactic acidosis induced by the NDUFV1 mutations could be partially corrected with the vitamins riboflavin and thiamine or with sodium dichloroacetate, an activator of the pyruvate dehydrogenase complex, resulting in significant increases in animal fitness. Surprisingly, cytochrome c oxidase activity and protein levels were reduced, establishing a connection between complexes I and IV. Our results indicate that complex I mutations exert their pathogenic effects in multiple ways: by impeding the metabolism of NADH, by increasing the production of reactive oxygen species, and by interfering with the function or assembly of other mitochondrial respiratory chain components.
* To whom correspondence should be addressed. Tel: +1 7804924853; Fax: +1 7804820886; Email: bernard.lemire{at}ualberta.ca
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
M. C. K. Leung, P. L. Williams, A. Benedetto, C. Au, K. J. Helmcke, M. Aschner, and J. N. Meyer Caenorhabditis elegans: An Emerging Model in Biomedical and Environmental Toxicology Toxicol. Sci., November 1, 2008; 106(1): 5 - 28. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Marques, N. A. Dencher, A. Videira, and F. Krause Supramolecular Organization of the Respiratory Chain in Neurospora crassa Mitochondria Eukaryot. Cell, December 1, 2007; 6(12): 2391 - 2405. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Han, T. H. Lee, J. Y. Mun, M. J. Kim, E. A. Kritikou, S.-J. Lee, S. S. Han, M. O. Hengartner, and H.-S. Koo Deleted in cancer 1 (DICE1) is an essential protein controlling the topology of the inner mitochondrial membrane in C. elegans Development, September 15, 2006; 133(18): 3597 - 3606. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. I. Grad, L. C. Sayles, and B. D. Lemire Introduction of an additional pathway for lactate oxidation in the treatment of lactic acidosis and mitochondrial dysfunction in Caenorhabditis elegans PNAS, December 20, 2005; 102(51): 18367 - 18372. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Duarte, U. Schulte, A. V. Ushakova, and A. Videira Neurospora Strains Harboring Mitochondrial Disease-Associated Mutations in Iron-Sulfur Subunits of Complex I Genetics, September 1, 2005; 171(1): 91 - 99. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. L. Taylor, J. L. Heazlewood, D. A. Day, and A. H. Millar Differential Impact of Environmental Stresses on the Pea Mitochondrial Proteome Mol. Cell. Proteomics, August 1, 2005; 4(8): 1122 - 1133. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. U. Rao, L. K. Carta, E. Lesuisse, and I. Hamza Lack of heme synthesis in a free-living eukaryote PNAS, March 22, 2005; 102(12): 4270 - 4275. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. V. Dudkina, H. Eubel, W. Keegstra, E. J. Boekema, and H.-P. Braun Structure of a mitochondrial supercomplex formed by respiratory-chain complexes I and III PNAS, March 1, 2005; 102(9): 3225 - 3229. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Ugalde, R. J.R.J. Janssen, L. P. van den Heuvel, J. A.M. Smeitink, and L. G.J. Nijtmans Differences in assembly or stability of complex I and other mitochondrial OXPHOS complexes in inherited complex I deficiency Hum. Mol. Genet., March 15, 2004; 13(6): 659 - 667. [Abstract] [Full Text] [PDF] |
||||






