FIG. 3.

Subcellular localization, enzymatic activity, and selected substrates of the seven mammalian sirtuins. SIRT1, SIRT6, and SIRT7 localize to the nucleus, SIRT2 is cytoplasmic, and SIRT3, SIRT4, and SIRT5 are mitochondrial. SIRT1 and SIRT2 may shuttle between their respective compartments. See the text for ANT, adenine nucleotide translocator; G6PD, glucose-6-phosphate dehydrogenase; GABPβ1, GA repeat binding protein beta 1; GDH, glutamate dehydrogenase; IDH2, isocitrate dehydrogenase 2; LCAD, long chain acyl-CoA dehydrogenase; NDUFA9, NADH:ubiquinone oxidoreductase subunit A9; NRF, nuclear respiratory factor; OPA1, optic atrophy 1; PDH, pyruvate dehydrogenase; PGAM-1, phosphoglycerate mutase-1; PGC-1?, peroxisome proliferator-activated receptor coactivator-1?; SIRT, sirtuin; SOD, superoxide dismutase; SREBP1, sterol regulatory element binding protein 1.