apolipoprotein A-I

ap·o·lip·o·pro·tein A-I

an apolipoprotein found in HDL and chylomicrons. It is an activator of LCAT and a ligand for the HDL receptor. A deficiency of this apolipoprotein has been associated with low HDL levels and with Tangier disease.

APOA1

A gene on chromosome 11q23-q24 that encodes apolipoprotein A1, the main protein component of high-density lipoprotein (HDL) in plasma, which promotes cholesterol efflux from tissues to the liver for excretion and is a cofactor for lecithin cholesterolacyltransferase (LCAT), which is responsible for forming most plasma cholesteryl esters.
 
Molecular pathology
APOA1 mutations cause HDL deficiency (e.g., Tangier disease and systemic non-neuropathic amyloidosis).

apolipoprotein A-I

A 28 kD single chain protein that comprises 75% of the ApoA in HDL; apoA-I is the major protein constituent of lipoproteins, and participates in cholesterol transport by activating LCAT-lecithin:cholesterol acyltransferase; apoA-I levels are inversely proportional to the risk of CAD