|Organism||Saccharomyces cerevisiae (replicative)|
|Aging Phenotype||Shortened life-span|
|Description||Deletion of SIR3 shortens life-span by approximately 20% (Kaeberlein et al., 1999). This reduction in life span is suppressed by preventing mating type heterozygosity.|
The S275A allele of Sir3p results in a 40% increase in mean and maximum life-span (Ray et al., 2003). This allele prevents phosphorylation of Sir3p.
|Gene Function||silencing factor|
|Other Phenotypes||sir3 mutants show loss of silencing at the silent mating type loci (Shore et al., 1984; Rine and Herskowitz, 1987) and telomeres (Aparicio et al., 1991) and have a slightly elevated level of rDNA marker loss (Kaeberlein et al., 1999).|
S.p. orc1, cdc18
|Primary Reference||Kaeberlein, M., McVey, M., and Guarente, L. (1999). The SIR2/3/4 complex and SIR2 alone promote longevity in Saccharomyces cerevisiae by two different mechanisms. Genes Dev 13, 2570-80. [Abstract]|
|Other References||Rine, J., and Herskowitz, I. (1987). Four genes responsible for a position effect on expression from HML and HMR in Saccharomyces cerevisiae. Genetics 116, 9-22. [Abstract]|
Shore, D., Squire, M., and Nasmyth, K. A. (1984). Characterization of two genes required for the position-effect control of yeast mating-type genes. Embo J 3, 2817-23. [Abstract]
Aparicio, O. M., Billington, B. L., and Gottschling, D. E. (1991). Modifiers of position effect are shared between telomeric and silent mating-type loci in S. cerevisiae. Cell 66, 1279-87. [Abstract]
Ray, A., Hector, R. E., Roy, N., Song, J., Berkner, K. L., and Runge, K. W. (2003). Sir3p phosphorylation by the Slt2p pathway effects redistribution of silencing function and shortened lifespan. Nat Genet Published online 17 March 2003.
|Relevant Links||SGD: http://genome-www4.stanford.edu/cgi-bin/SGD/locus.pl?locus=sir3|
|Keywords||DNA damage, silencing, signaling, chromatin, telomeres, rDNA, sterility, recombination, yeast, replicative senescence, Saccharomyces, cerevisiae, DNA, non-homologous end-joining, transcription|