Table 1.

The role of SIRT1 and its effects in response to DNA damage.

Role of SIRT1	Effects	Cell or Tissue Type	Reference
Protection against DNA damage	Absence of 6-4PP and Pt-GG in heterochromatin associated with SIRT1	Human fibroblasts	[20]
	Decreased levels of 8-OHdG after the increase in SIRT1 activity and mRNA level	Rat hippocampus	[64]
Regulation of genomic stability and transcriptional changes	Relocalization of Sir2/3/4 and de-repression of epigenetically silencing genes in response to DNA damage	Yeast	[69]
	Relocalization of SIRT1 to DSBs followed by transcriptional changes	Mammalian stem cells	[67]
	Recruitment of key epigenetic proteins (DNMTs, EZH2) to DNA damage site	Normal and cancer cells	[28,55,60,62,71]
	Deacetylation of HAT (hMOF) and E2F1 leading to downregulation of genes involved in DNA repair and genomic stability	Cancer cells	[48,74]
	Recruitment of DNA repair proteins contributing with viral activity, including gene transcription	Keratinocytes containing HPV episomes	[78]
Modulation of DDR and DNA repair	Deacetylation of p53 interfering in cell death	Normal and cancer cells	reviewed in [41]
	Deacetylation of γH2AX, Rad51, BRCA1 and NBS1, regulating the foci formation	MEFs	[52]
	Interaction with Ku70 protein belonging to NHEJ	Cancer cells	[88,89,90,91,92]
	Deacetylation of FOXO family favoring the expression of target repair genes, cell cycle arrest and resistance to oxidative stress	Normal cells	[81,82,83,84]
	Regulation of many important proteins to DDR and DNA repair, including ATM, NBS1, WRN, KAP1, XPA, MSH2, MSH6, APEX1	Normal and cancer cells	[11,97,99,100,101,102,103,104,106]