ABHD5

1-acylglycerol-3-phosphate O-acyltransferase ABHD5, also known as comparative gene identification-58 (CGI-58), is an enzyme that in humans is encoded by the ABHD5 gene.

Function
The protein encoded by this gene belongs to a large family of proteins defined by an alpha/beta hydrolase fold, and contains three sequence motifs that correspond to a catalytic triad found in the esterase/lipase/thioesterase subfamily. It differs from other members of this subfamily in that its putative catalytic triad contains an asparagine instead of the serine residue. Mutations in this gene have been associated with Chanarin-Dorfman syndrome, a triglyceride storage disease with impaired long-chain fatty acid oxidation.

CGI-58 is known to be a co-activator of adipose triglyceride lipase (ATGL/PNPLA2) that associates with lipid droplets in association with perilipin proteins. Phosphorylation of certain perilipins by protein kinase A causes dissociation of CGI-58 from the perilipins and permits interaction with ATGL. CGI-58 additionally interacts with beclin 1, and CGI-58 has been shown to promote autophagy in colorectal cancer in a PNPLA2-independent manner.