Overview:

SIRT1 is a member of the sirtuin family of proteins which are homologs to the yeast Sir2 protein. Each member of the Sirtuin family contain sirtuin core domains. These proteins are grouped into four classes with SIRT1 being a member of class I. SIRT1 is a stress-response and chromatin-silencing factor (1). It is an NAD(+)-dependent histone deacetylase involved in various nuclear events such as transcription, DNA replication, and DNA repair. SIRT1 protein binds and deacetylates the p53 protein (2). Expression of wild type SIRT1 in human cells reduces the transcriptional activity of p53 indicating that SIRT1 is involved in the regulation of p53 function via deacetylation.

References:

1. Tanny, J. C. et al: An enzymatic activity in the yeast Sir2 protein that is essential for gene silencing. Cell 99: 735-745, 1999.2. Vaziri, H. et al: hSIR2-SIRT1 functions as an NAD-dependent p53 deacetylase. Cell 107: 149-159, 2001.