Mitochondrial mutations differentially affect aging, mutability and anesthetic sensitivity in Caenorhabditis elegans

In the nematode Caenorhabditis elegans, mutations have been previously isolated that affect the activities of Complex I (gas-1) and Complex II (mev-1), two of the five membrane-bound complexes that control electron flow in mitochondrial respiration. We compared the effects of gas-1 and mev-1 mutations on different traits influenced by mitochondrial function. Mutations in Complex I and II both increased sensitivity to free radicals as measured during development and in aging animals. However, gas-1 and mev-1 mutations differentially affected mutability and anesthetic sensitivity. Specifically, gas-1 was anesthetic hypersensitive but not hypermutable while mev-1 was hypermutable but displayed normal responses to anesthetics. These results indicate that Complexes I and II may differ in their effects on behavior and development, and are consistent with the wide variation in phenotypes that result from mitochondrial changes in other organisms. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.