LCAT : lecithin-cholesterol acyltransferase

Description

The LCAT (lecithin-cholesterol acyltransferase) is a protein-coding gene located on chromosome 16.

The LCAT gene provides instructions for making an enzyme called lecithin-cholesterol acyltransferase (LCAT). This enzyme plays a role in removing cholesterol from the blood and tissues. Cholesterol is a waxy, fat-like substance that is produced in the body and obtained from foods that come from animals (particularly egg yolks, meat, poultry, fish, and dairy products). The body needs this substance to build cell membranes, make certain hormones, and produce compounds that aid in fat digestion. Too much cholesterol, however, increases a person's risk of developing heart disease, and can also lead to buildup of cholesterol in other tissues. The LCAT enzyme helps transport cholesterol out of the blood and tissues by a process called cholesterol esterification. This process results in a form of cholesterol that is more efficiently carried by molecules called lipoproteins, which transport the cholesterol to the liver. Once in the liver, the cholesterol is redistributed to other tissues or removed from the body. The enzyme has two major functions, called alpha- and beta-LCAT activity. Alpha-LCAT activity helps attach cholesterol to a lipoprotein called high-density lipoprotein (HDL). Beta-LCAT activity helps attach cholesterol to other lipoproteins called very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL).

LCAT is a central enzyme in the extracellular metabolism of plasma lipoproteins. It is synthesized mainly in the liver and secreted into plasma where it converts cholesterol and phosphatidylcholines (lecithins) to cholesteryl esters and lysophosphatidylcholines on the surface of high and low density lipoproteins (HDLs and LDLs). The cholesterol ester is then transported back to the liver. LCAT has a preference for plasma 16:0-18:2 or 18:O-18:2 phosphatidylcholines. It is also produced in the brain by primary astrocytes, and esterifies free cholesterol on nascent APOE-containing lipoproteins secreted from glia and influences cerebral spinal fluid (CSF) APOE- and APOA1 levels. Together with APOE and the cholesterol transporter ABCA1, it plays a key role in the maturation of glial-derived, nascent lipoproteins. It is required for remodeling high-density lipoprotein particles into their spherical forms. LCAT catalyzes the hydrolysis of 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine (platelet-activating factor or PAF) to 1-O-alkyl-sn-glycero-3-phosphocholine (lyso-PAF). It also catalyzes the transfer of the acetate group from PAF to 1-hexadecanoyl-sn-glycero-3-phosphocholine forming lyso-PAF. LCAT catalyzes the esterification of (24S)-hydroxycholesterol (24(S)OH-C), also known as cerebrosterol to produce 24(S)OH-C monoesters.

LCAT is also known as -.

Associated Diseases

Comprehensive carrier screening

WES Whole Exome Sequencing

Clinical Exome Sequencing