SOAT1
Domain
Each protomer consists of 9 transmembrane segments, which enclose a cytosolic tunnel and a transmembrane tunnel that converge at the predicted catalytic site: acyl-CoA enters the active site through the cytosolic tunnel, whereas cholesterol enters from the side through the transmembrane tunnel.
Function
Catalyzes the formation of fatty acid-cholesterol esters, which are less soluble in membranes than cholesterol (PubMed:16154994, PubMed:16647063, PubMed:32433613, PubMed:32433614, PubMed:32944968, PubMed:9020103). Plays a role in lipoprotein assembly and dietary cholesterol absorption (PubMed:16154994, PubMed:9020103). Preferentially utilizes oleoyl-CoA ((9Z)-octadecenoyl-CoA) as a substrate: shows a higher activity towards an acyl-CoA substrate with a double bond at the delta-9 position (9Z) than towards saturated acyl-CoA or an unsaturated acyl-CoA with a double bond at the delta-7 (7Z) or delta-11 (11Z) positions (PubMed:11294643, PubMed:32433614).
Sequence Similarities
Belongs to the membrane-bound acyltransferase family. Sterol o-acyltransferase subfamily.
Cellular localization
- Endoplasmic reticulum membrane
- Multi-pass membrane protein
Alternative names
ACACT, ACACT1, ACAT, ACAT1, SOAT, STAT, SOAT1, Sterol O-acyltransferase 1, Acyl-coenzyme A:cholesterol acyltransferase 1, Cholesterol acyltransferase 1, ACAT-1