NameNNT1
OrganismSaccharomyces cerevisiae (replicative)
Aging PhenotypeLife-span extension
Allele TypeOverexpression
StrainPSY316
DescriptionOverexpression of YLR285W by 5-fold increases life-span by about 30% (Anderson et al., 2003). This is the same magnitude of life-span extension as obtained with low-glucose calorie restriction and growth on low-glucose fails to further extend the life-span of cells overexpressing YLR285W.
Gene FunctionNicotinamide N-methyltransferase. Converts nicotinamide to N-methylnicotinamide.
Other PhenotypesNicotinamide is a potent inhibitor of Sir2p (Bitterman et al., 2002). It is thought that NNT1 regulates longevity by altering Sir2p activity (Anderson et al., 2003).
Overexpression of NNT1 increases rDNA silencing, whereas deletion decreases rDNA silencing (Anderson et al., 2003). Overexpression of human nicotinamide N-methyltransferase in yeast increases rDNA silencing (Anderson et al., 2003).
Homologs
Primary ReferenceAnderson, R. M., Bitterman, K. J., Wood, J. G., Medvedik, O., and Sinclair, D. A. (2003). Nicotinamide and PNC1 govern lifespan extension by calorie restriction in Saccharomyces cerevisiae. Nature 423, 181-5. [Abstract]
Other ReferencesBitterman, K. J., Anderson, R. M., Cohen, H. Y., Latorre-Esteves, M., and Sinclair, D. A. (2002). Inhibition of silencing and accelerated aging by nicotinamide, a putative negative regulator of yeast sir2 and human SIRT1. J Biol Chem 277, 45099-107. [Abstract]
Relevant LinksSGD: http://genome-www4.stanford.edu/cgi-bin/SGD/locus.pl?locus=NNT1
Keywordsnicotinamide, silencing, replicative capacity, caloric restriction, calorie restriction, CR, rDNA, silencing, yeast, replicative senescence, Saccharomyces, cerevisiae, metabolism, NAD