Abstract
age-1(hx546) is a recessive mutant allele in Caenorhabditis elegans that results in an increase in mean life span averaging 40% and in maximal life span averaging 60% at 20°; at 25° age-1(hx546) averages a 65% increase in mean life span (25.3 days vs. 15.0 days) and a 110% increase in maximum life span (46.2 days vs. 22.0 days for wild-type hermaphrodites). Mutant males also show extended life spans. age-1(hx546) is associated with a 75% decrease in hermaphrodite self-fertility as compared to the age-1(+) allele at 20°. Using two novel strategies for following the segregation of age-1, we present evidence that longer life results from a mutation in a single gene that increases the probability of survival at all chronological ages. The long-life and reduced-fertility phenotypes cosegregate and are tightly linked to fer-15, a locus on linkage group II. age-1(hx546) does not affect the timing of larval molts, the length of embryogenesis, food uptake, movement, or behavior in any way tested. Although age-1(hx546) lowers hermaphrodite self-fertility, it does not markedly affect the length of the reproductive period with all the increase in life expectancy due to an increase in the length of postreproductive life. In so far as we are aware, this mutant in age-1 is the only instance of a well-characterized genetic locus in which the mutant form results in lengthened life. It is likely that the action of age-1 in lengthening life results not from eliminating a programmed aging function but rather from reduced hermaphrodite self-fertility or from some other unknown metabolic or physiologic alteration.
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- Brenner S. The genetics of Caenorhabditis elegans. Genetics. 1974 May;77(1):71–94. doi: 10.1093/genetics/77.1.71. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cassada R. C., Russell R. L. The dauerlarva, a post-embryonic developmental variant of the nematode Caenorhabditis elegans. Dev Biol. 1975 Oct;46(2):326–342. doi: 10.1016/0012-1606(75)90109-8. [DOI] [PubMed] [Google Scholar]
- Emmons S. W., Yesner L. High-frequency excision of transposable element Tc 1 in the nematode Caenorhabditis elegans is limited to somatic cells. Cell. 1984 Mar;36(3):599–605. doi: 10.1016/0092-8674(84)90339-8. [DOI] [PubMed] [Google Scholar]
- Gould A. B., Clark A. M. X-ray induced mutations causing adult life-shorting in Drosophila melanogaster. Exp Gerontol. 1977;12(3-4):107–112. doi: 10.1016/0531-5565(77)90017-1. [DOI] [PubMed] [Google Scholar]
- Hamilton W. D. The moulding of senescence by natural selection. J Theor Biol. 1966 Sep;12(1):12–45. doi: 10.1016/0022-5193(66)90184-6. [DOI] [PubMed] [Google Scholar]
- Hodgkin J. Male Phenotypes and Mating Efficiency in CAENORHABDITIS ELEGANS. Genetics. 1983 Jan;103(1):43–64. doi: 10.1093/genetics/103.1.43. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Johnson T. E., McCaffrey G. Programmed aging or error catastrophe? An examination by two-dimensional polyacrylamide gel electrophoresis. Mech Ageing Dev. 1985 May 31;30(3):285–297. doi: 10.1016/0047-6374(85)90118-6. [DOI] [PubMed] [Google Scholar]
- Johnson T. E., Mitchell D. H., Kline S., Kemal R., Foy J. Arresting development arrests aging in the nematode Caenorhabditis elegans. Mech Ageing Dev. 1984 Nov;28(1):23–40. doi: 10.1016/0047-6374(84)90150-7. [DOI] [PubMed] [Google Scholar]
- Klass M. R. A method for the isolation of longevity mutants in the nematode Caenorhabditis elegans and initial results. Mech Ageing Dev. 1983 Jul-Aug;22(3-4):279–286. doi: 10.1016/0047-6374(83)90082-9. [DOI] [PubMed] [Google Scholar]
- Klass M. R. Aging in the nematode Caenorhabditis elegans: major biological and environmental factors influencing life span. Mech Ageing Dev. 1977 Nov-Dec;6(6):413–429. doi: 10.1016/0047-6374(77)90043-4. [DOI] [PubMed] [Google Scholar]
- Klass M., Hirsh D. Non-ageing developmental variant of Caenorhabditis elegans. Nature. 1976 Apr 8;260(5551):523–525. doi: 10.1038/260523a0. [DOI] [PubMed] [Google Scholar]
- Martin G. M. Genetic syndromes in man with potential relevance to the pathobiology of aging. Birth Defects Orig Artic Ser. 1978;14(1):5–39. [PubMed] [Google Scholar]
- Masoro E. State of knowledge on action of food restriction and aging. Basic Life Sci. 1985;35:105–116. doi: 10.1007/978-1-4899-2218-2_5. [DOI] [PubMed] [Google Scholar]
- Sigurdson D. C., Spanier G. J., Herman R. K. Caenorhabditis elegans deficiency mapping. Genetics. 1984 Oct;108(2):331–345. doi: 10.1093/genetics/108.2.331. [DOI] [PMC free article] [PubMed] [Google Scholar]