NameHAP4
OrganismSaccharomyces cerevisiae (replicative)
Aging PhenotypeLife-span extension
Allele TypeOverexpression
StrainPSY316
DescriptionOverexpression of HAP4 from the ADH1 promoter extends life-span approximately 40% under growth conditions favoring fermentation (2% glucose) (Lin et al., 2002). Overexpression of HAP4 combined with calorie restriction (CR) fails to further extend life-span. Like CR, life-span extension by HAP4 requires SIR2.
Gene FunctionCAATT box transcription factor required for the metabolic shift from fermenation to respiration under glucose limiting growth.
Other PhenotypesHAP4 overexpressing cells demonstrate a transcriptional response resembling cells undergoing diauxic shift, consume more oxygen than wild type cells, and show increased Sir2p-dependent transcriptional silencing at telomeres and rDNA (Lin et al., 2002).
Homologs
Primary ReferenceLin, S. J., Kaeberlein, M., Andalis, A. A., Sturtz, L. A., Defossez, P. A., Culotta, V. C., Fink, G. R., and Guarente, L. (2002). Calorie restriction extends Saccharomyces cerevisiae lifespan by increasing respiration. Nature 418, 344-8. [Abstract]
Other References
Relevant LinksSGD: http://genome-www4.stanford.edu/cgi-bin/SGD/locus.pl?locus=HAP4
Keywordsoxygen, oxidative stress, yeast, replicative senescence, fermentation, respiration, transcription factor, calorie restriction