Page last updated: 2024-10-24

diacylglycerol O-acyltransferase activity

Definition

Target type: molecularfunction

Catalysis of the reaction: acyl-CoA + 1,2-diacylglycerol = CoA + triacylglycerol. [EC:2.3.1.20]

Diacylglycerol O-acyltransferase (DGAT) activity is a crucial enzyme function in lipid metabolism, specifically involved in the final step of triglyceride synthesis. This enzymatic activity catalyzes the transfer of a fatty acyl group from a fatty acyl-CoA donor molecule to the sn-3 position of diacylglycerol (DAG). This process results in the formation of a triglyceride molecule, which is a primary energy storage form in the body.

DGAT activity plays a vital role in various biological processes:

* **Lipid Storage:** DGAT enzymes are essential for the efficient storage of dietary fats in adipose tissue. They contribute to the synthesis of triglycerides, which serve as a major energy reservoir.
* **Lipoprotein Assembly:** DGAT activity is crucial for the production of very-low-density lipoproteins (VLDL) in the liver. These lipoproteins transport triglycerides from the liver to peripheral tissues for energy utilization.
* **Membrane Lipid Homeostasis:** DGAT enzymes contribute to the maintenance of membrane lipid composition by regulating the levels of triglycerides, which are structural components of cell membranes.

The specific molecular function of DGAT activity involves several key aspects:

* **Substrate Recognition:** DGAT enzymes exhibit selectivity towards DAG and fatty acyl-CoA substrates. They possess specific binding sites that recognize and interact with these molecules.
* **Catalytic Mechanism:** The enzymatic reaction catalyzed by DGAT activity involves the formation of a temporary covalent intermediate between the enzyme and the fatty acyl-CoA substrate. This intermediate facilitates the transfer of the fatty acyl group to DAG.
* **Product Release:** Once the triglyceride molecule is synthesized, it is released from the enzyme, allowing for the continuation of the catalytic cycle.

DGAT activity is regulated by various factors, including dietary intake, hormones, and cellular signaling pathways. The precise regulation of this enzymatic activity is crucial for maintaining lipid homeostasis and preventing metabolic disorders.

There are two primary isoforms of DGAT enzymes, DGAT1 and DGAT2, each with distinct roles and regulatory mechanisms. Understanding the molecular function of DGAT activity is essential for developing therapeutic strategies targeting lipid metabolism disorders, such as obesity, diabetes, and hyperlipidemia.'
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Proteins (3)

ProteinDefinitionTaxonomy
Diacylglycerol O-acyltransferase 2A diacylglycerol O-acyltransferase 2 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q96PD7]Homo sapiens (human)
Diacylglycerol O-acyltransferase 2A diacylglycerol O-acyltransferase 2 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q96PD7]Homo sapiens (human)
Diacylglycerol O-acyltransferase 1A diacylglycerol O-acyltransferase 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:O75907]Homo sapiens (human)

Compounds (6)

CompoundDefinitionClassesRoles
azd3988AZD3988: for treatment of obesity and diabetes; structure in first source
a-922500aromatic ketone
azd7687AZD7687: structure in first source
pf-04620110PF-04620110: a DGAT1 inhibitor; structure in first source
pradigastat
pf-06424439PF-06424439: an inhibitor of diacylglycerol acyltransferase 2; structure in first source