apolipoprotein E(redirected from Apo E)
an apolipoprotein found in several plasma lipoprotein particles including chylomicrons, VLDL, and HDL. Three major isoforms are encoded by three common alleles at the Apo E locus: E2, E2, and E4. The E2 allele is associated with lower total plasma cholesterol and LDL cholesterol than is E3, whereas E4 is associated with higher LDL and total cholesterol than E3.
a protein component of lipoprotein complexes found in very-low-density lipoprotein (VLDL), high-density lipoprotein, chylomicrons, and chylomicron remnants. It facilitates hepatic uptake of chylomicron and VLDL remnants and is elevated in patients with type III hyperlipoproteinemia. One form of apolipoprotein E has been linked to Alzheimer's disease.
APOEA gene on chromosome 19q13.2 that encodes apolipoprotein E, the main apoprotein of chylomicrons, which binds to a specific receptor on liver cells and peripheral cells. ApoE mediates binding, internalisation and catabolism of lipoprotein particles and serves as a ligand for the LDL (apo B/E) receptor.
APOE mutations cause hyperlipoproteinaemia type III (familial dysbetalipoproteinaemia), which is characterised by increased plasma cholesterol and triglycerides due to impaired chylomicron and VLDL remnant clearance.