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

In the nematode Caenorhabditis elegans, mutations have been previously isol ated 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 mi tochondrial respiration. We compared the effects of gas-1 and mev-1 mutatio ns on different traits influenced by mitochondrial function. Mutations in C omplex I and II both increased sensitivity to free radicals as measured dur ing development and in aging animals. However, gas-1 and mev-1 mutations di fferentially affected mutability and anesthetic sensitivity. Specifically, gas-1 was anesthetic hypersensitive but not hypermutable while mev-1 was hy permutable but displayed normal responses to anesthetics. These results ind icate that Complexes I and II may differ in their effects on behavior and d evelopment, and are consistent with the wide variation in phenotypes that r esult from mitochondrial changes in other organisms. (C) 2001 Elsevier Scie nce Ireland Ltd. All rights reserved.