Table 4.

Examples of nuclear SIRT6 and SIRT7 substrates and functions

Sirtuins	Sirtuin substrates	Sirtuin functions
SIRT6	CtIP	Deacetylates it to promote DNA end resection53
	DNA-PK	Deacetylates and stabilizes it at chromatin for DNA double-strand break repair52
	GCN5	Interacts with and modifies GCN5, enhancing GCN5’s activity to acetylate PGC1α and suppresses hepatic glucose production59
	Histone H3K56	Deacetylates H3K56 to promote genomic stability19,156
	Histone H3K9	Deacetylates H3K9: maintains telomeric chromatin;46,57 represses NF-κB50 and HIF1α51,60 dependent gene expression; attenuates IGF-Akt signaling58
	PARP1	Mono-ADP-ribosylates it, thereby stimulating its poly-ADP-ribosylase activity and enhancing DSB repair under oxidative stress56
	TNF-α	Removes the fatty acyl modification on K19 and K20 of TNF-α to promote its secretion47
SIRT7	Histone H3K18	Maintains the transformation phenotype of cancer cells18

Abbreviations: ADP, adenosine diphosphate; CtIP, C-terminal binding protein interacting protein; DNA-PK, DNA-dependent protein kinase; HIF1α, hypoxia-inducible factor 1-alpha; IGF, insulin-like growth; NF-κB, nuclear factor kappa-light-chain-enhancer of activated B cells; PARP1, poly(adenosine diphosphate ribose) polymerase 1; PGC1α, peroxisome proliferator-activated receptor gamma coactivator 1-alpha; TNF, tumor necrosis factor.