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.
a protein component of lipoprotein complexes found in high-density lipoprotein (HDL) and chylomicrons. It is an activator of lecithin-cholesterol acyltransferase, which forms cholesteryl esters in HDL. All apoproteins of plasma lipoproteins bind and transport lipid in the blood. A deficiency of apolipoprotein A-I is associated with low HDL levels and Tangier disease.
APOA1A 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.
APOA1 mutations cause HDL deficiency (e.g., Tangier disease and systemic non-neuropathic amyloidosis).