Sex-specific effects of the DAF-12 steroid receptor on aging in Caenorhabditis elegans.
Sex differences in longevity and aging are seen throughout the animal kingdom. These are likely to result, in part, from sex differences in endocrinology. In the nematode Caenorhabditis elegans, males are the longer-lived sex. Here we explore the possibility that sex differences in insulin/insulin-like growth factor 1 (IGF-1) and steroid endocrinology contribute to this sex difference in aging by studying C. elegans populations in liquid culture. We report that in hermaphrodite populations, mutational loss of the DAF-12 steroid receptor affected life span as in previous plate-culture studies: mutant longevity is suppressed in a weak daf-2 insulin/IGF-1 receptor mutant but enhanced in a stronger daf-2 mutant. However, in males, mutation of daf-12 had little effect on aging in either weak or strong daf-2 mutants. Moreover, while mutation of daf-12 marginally reduced life span in daf-2(+) hermaphrodites, as in plate-cultured populations, it did not in daf-2(+) males. These results could imply that in C. elegans, as in mammals, sex differences in steroid endocrinology contribute to sex differences in aging.
Cetre for Research on Ageing, Department of Biology, University College London, London WC1E 6BT, UK.
Diana
D
McCulloch
David
D
Gems
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D012734:Disorders of Sex Development / Q000235:genetics / Q000378:metabolism; D005260:Female; D017353:Gene Deletion; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism; D008136:Longevity / Q000235:genetics*; D008297:Male; D011972:Receptor, Insulin / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics* / Q000378:metabolism; D012727:Sex Characteristics
D029742:Caenorhabditis elegans Proteins; C410905:DAF-12 protein, C elegans; D018160:Receptors, Cytoplasmic and Nuclear; D007334:Insulin-Like Growth Factor I; C107483:DAF-2 protein, C elegans; D011972:Receptor, Insulin