sirtuin(redirected from Sir2 proteins)
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Any of a family of enzymes that occur in all living organisms and are thought to regulate cellular aging, apoptosis, and resistance to stress in more complex eukaryotic organisms.
[Alteration of Sir2, name of the first gene coding for the synthesis of such enzymes to be isolated (short for s(ilent mating-type) i(nformation) r(egulation) 2, so called because the gene silences the expression of genes relating to the two mating types of the yeast from which it was isolated ) + -in.]
a protein that regulates cell metabolism and ageing