Fig. 3.
Cytosolic acetyl-CoA metabolism and protein acetylation. Citrate generated from acetyl-CoA is transported into the cytosol where it is a substrate for ATP citrate lyase (ACLY). This enzyme converts citrate back to acetyl-CoA in the presence of ATP. Acetyl-CoA can be also synthetized by cytosolic acetyl-CoA synthetase (ACECS1) from acetate, CoA and ATP. Similarly, as in mitochondria, acetyl-CoA is used for acetylation of proteins by acetyltransferases (KAT). The acetylated proteins are deacetylated by sirtuins where the deacetylation is coupled to NAD+ hydrolysis and o-acetyl-ADP-ribose is released.