ACACA

Acetyl-CoA carboxylase (ACC) is a complex multifunctional enzyme system. ACC is a biotin-containing enzyme which catalyzes the carboxylation of acetyl-CoA to malonyl-CoA, the rate-limiting step in fatty acid synthesis. There are two ACC forms, alpha and beta, encoded by two different genes. ACC-alpha is highly enriched in lipogenic tissues. The enzyme is under long term control at the transcriptional and translational levels and under short term regulation by the phosphorylation/dephosphorylation of targeted serine residues and by allosteric transformation by citrate or palmitoyl-CoA. Multiple alternatively spliced transcript variants divergent in the 5' sequence and encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Acetyl-CoA Carboxylase Alpha

Cytosolic enzyme that catalyzes the carboxylation of acetyl-CoA to malonyl-CoA, the first and rate-limiting step of de novo fatty acid biosynthesis. This is a 2 steps reaction starting with the ATP-dependent carboxylation of the biotin carried by the biotin carboxyl carrier (BCC) domain followed by the transfer of the carboxyl group from carboxylated biotin to acetyl-CoA.

Acetyl-CoA metabolic process
Carnitine shuttle
Cellular response to prostaglandin E stimulus
Fatty acid biosynthetic process
Fatty-acyl-CoA biosynthetic process
Lipid homeostasis
Malonyl-CoA biosynthetic process
Positive regulation of cellular metabolic process
Protein homotetramerization
Protein metabolic process
Regulation of lipid metabolic process
Tissue homeostasis

Cytosol

An inborn error of de novo fatty acid synthesis associated with severe brain damage, persistent myopathy and poor growth.

Phosphorylation on Ser-1263 is required for interaction with BRCA1.
Phosphorylation at Ser-80 by AMPK inactivates enzyme activity.
The biotin cofactor is covalently attached to the central biotinyl-binding domain and is required for the catalytic activity.