Authors: Yang W; Li J; Hekimi S
Abstract: SOD-1 and SOD-2 detoxify superoxide in the cytoplasm and mitochondria. We find that, although several long-lived mutants of Caenorhabditis elegans have increased SOD levels, this phenomenon does not correlate with life span or growth rate. Furthermore, although disruption of sod-1 or -2 expression produces numerous phenotypes, including increased sensitivity to paraquat and increased oxidative damage to proteins (except in daf-2 mutants), this fails to shorten the life span of these long-lived mutants. In fact, sod-1(RNAi) increases the life span of daf-2 mutants and sod-2(RNAi) that of clk-1 mutants. Our results suggest that increased superoxide detoxification and low oxidative damage are not crucial for the longevity of the mutants examined, with the possible exception of daf-2, where our results are inconclusive. These results are surprising because several of the long-lived mutants that we examined specifically affect mitochondrial electron transport, a process whose involvement in life-span determination is believed to be related to superoxide generation. We discuss the significance of our findings in light of the oxidative stress theory of aging.
Keywords: Animals; Caenorhabditis elegans/*genetics/physiology; *Genes, Mitochondrial; Longevity/*genetics; *Mutation; *Oxidative Stress; Superoxide Dismutase/analysis; Superoxides/*metabolism|
Journal: Genetics Volume: 177 Issue: 4 Pages: 2063-74 Date: Dec. 13, 2007 PMID: 18073424 |
Yang W, Li J, Hekimi S (2007) A Measurable increase in oxidative damage due to reduction in superoxide detoxification fails to shorten the life span of long-lived mitochondrial mutants of Caenorhabditis elegans. Genetics 177: 2063-74.
Comment on This Data Unit