Sterol O-acyltransferase
| sterol O-acyltransferase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
Chr. 1 q25 | |||||||
|---|---|---|---|---|---|---|---|
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Chr. 12 [1] | |||||||
|---|---|---|---|---|---|---|---|
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Sterol O-acyltransferase (also called Acyl-CoA cholesterol acyltransferase, Acyl-CoA cholesterin acyltransferase[citation needed] or simply ACAT) is an intracellular protein located in the endoplasmic reticulum that forms cholesteryl esters from cholesterol.
Sterol O-acyltransferase catalyzes the chemical reaction:
- acyl-CoA + cholesterol CoA + cholesterol ester
Thus, the two
This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups, the membrane-bound O-acyltransferases. This enzyme participates in bile acid biosynthesis.
Class and structure
Acyl-CoA cholesterol
In nearly all mammalian cells, ACAT catalyzes the intracellular
Mechanism
The mechanism scheme is as follows:
Acyl-CoA + Cholesterol ←→ CoA + Cholesteryl ester[2]
Isoforms
There are two
SOAT1 (ACAT1)
Previous studies have shown that SOAT modulates proteolytic processing in cell-based and animal models of
SOAT2 (ACAT2)
In a recent study, it was shown that SOAT2 activity is upregulated as a result of chronic renal failure. This study was specific to hepatic SOAT, which plays a major role in hepatic production and release of very low density lipoprotein (
Yeast
In yeast, acyl-CoA:sterol acyltransferase (ASAT) is functionally equivalent to ACAT. Although studies in vitro and in yeast suggest that the acyl-CoA binding protein (ACBP) may modulate long-chain fatty acyl-CoA (LCFA-CoA) distribution, the physiological function in mammals is unresolved. Recent research suggests that ACBP expression may play a role in LCFA-CoA metabolism in a physiological context.[5]
In
Plant Synthesis of Steryl Esters
In
See also
- ACAT1 mRNA
- Lecithin—cholesterol acyltransferase(LCAT)
References
Further reading
- Figure 2 of the esterification reaction with one molecule of free cholesterol, oleic acid, catalyzed by acyl-CoA: cholesterol acyltransferase. It gives the cholesterol ester cholesterol oleate. from Sigrid Hahn; Hans-Ulrich Klör (2001). Knoll Lexikon Adipositas. Aesopus-Verlag. ISBN 978-3-7773-1774-8. Retrieved 22 June 2013(German) Encyclopedia obesity)
{{cite book}}: CS1 maint: postscript (link - Sgoutas DS (1970). "Effect of geometry and position of ethylenic bond upon acyl coenzyme A--cholesterol-O-acyltransferase". Biochemistry. 9 (8): 1826–33. PMID 5439042.
- Spector AA, Mathur SN, Kaduce TL (1979). "Role of acylcoenzyme A: cholesterol o-acyltransferase in cholesterol metabolism". Prog. Lipid Res. 18 (1): 31–53. PMID 42927.
- Taketani S, Nishino T, Katsuki H (1979). "Characterization of sterol-ester synthetase in Saccharomyces cerevisiae". Biochim. Biophys. Acta. 575 (1): 148–55. PMID 389289.
