CES1

This gene encodes a member of the carboxylesterase large family. The family members are responsible for the hydrolysis or transesterification of various xenobiotics, such as cocaine and heroin, and endogenous substrates with ester, thioester, or amide bonds. They may participate in fatty acyl and cholesterol ester metabolism, and may play a role in the blood-brain barrier system. This enzyme is the major liver enzyme and functions in liver drug clearance. Mutations of this gene cause carboxylesterase 1 deficiency. Three transcript variants encoding three different isoforms have been found for this gene. [provided by RefSeq, Jun 2010]

Carboxylesterase 1

Involved in the detoxification of xenobiotics and in the activation of ester and amide prodrugs (PubMed:7980644, PubMed:9169443, PubMed:9490062, PubMed:18762277).
Hydrolyzes aromatic and aliphatic esters, but has no catalytic activity toward amides or a fatty acyl-CoA ester (PubMed:7980644, PubMed:9169443, PubMed:9490062, PubMed:18762277).
Hydrolyzes the methyl ester group of cocaine to form benzoylecgonine (PubMed:7980644).
Catalyzes the transesterification of cocaine to form cocaethylene (PubMed:7980644).
Displays fatty acid ethyl ester synthase activity, catalyzing the ethyl esterification of oleic acid to ethyloleate (PubMed:7980644).
Converts monoacylglycerides to free fatty acids and glycerol. Hydrolyzes of 2-arachidonoylglycerol and prostaglandins (PubMed:21049984).
Hydrolyzes cellular cholesteryl esters to free cholesterols and promotes reverse cholesterol transport (RCT) by facilitating both the initial and final steps in the process (PubMed:18762277, PubMed:16024911, PubMed:11015575, PubMed:16971496).
First of all, allows free cholesterol efflux from macrophages to extracellular cholesterol acceptors and secondly, releases free cholesterol from lipoprotein-delivered cholesteryl esters in the liver for bile acid synthesis or direct secretion into the bile (PubMed:18762277, PubMed:18599737, PubMed:16971496).

Angiotensin maturation Source: Reactome
Cellular response to cholesterol Source: ARUK-UCL
Cellular response to low-density lipoprotein particle stimulus Source: ARUK-UCL
Cholesterol biosynthetic process Source: BHF-UCL
Cholesterol ester hydrolysis involved in cholesterol transport Source: BHF-UCL
Cholesterol homeostasis Source: ARUK-UCL
Cholesterol metabolic process Source: UniProtKB
Epithelial cell differentiation Source: UniProtKB
Lipid catabolic process Source: GO_Central
Medium-chain fatty acid metabolic process Source: BHF-UCL
Negative regulation of cholesterol storage Source: UniProtKB
Positive regulation of cholesterol efflux Source: UniProtKB
Positive regulation of cholesterol metabolic process Source: UniProtKB
Regulation of bile acid biosynthetic process Source: UniProtKB
Regulation of bile acid secretion Source: UniProtKB
Response to toxic substance Source: ProtInc
Reverse cholesterol transport Source: UniProtKB
Xenobiotic metabolic process Source: Reactome

Cytoplasm; Endoplasmic reticulum lumen; Lipid droplet. Moves from cytoplasm to lipid droplets upon lipid loading. Associates with lipid droplets independently of triglycerides (TG) content of the droplets and hydrolyzes cholesteryl esters more efficiently from mixed droplets.

Contains sialic acid.
Cleavage of the signal sequence can occur at 2 positions, either between Trp-17 and Gly-18 or between Gly-18 and His-19.