apolipoprotein E

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Related to apolipoprotein E: apolipoprotein E deficiency

ap·o·lip·o·pro·tein 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 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.

Molecular pathology
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.

apolipoprotein E

A 34-kD cholesterol-binding glycoprotein, which comprises 15% of VLDL; apoE maps to chromosome 19, is secreted by macrophages that mediate the uptake of lipoproteins–VLDL, HDL, LDL and cholesterol esters into cells via distinct binding domains for each receptor; apo-E has a central role in the metabolism of TG-rich lipoproteins, and mediates the uptake of chylomicrons and VLDL by the liver
References in periodicals archive ?
Apolipoprotein E phenotypes, dementia and mortality in a prospective population sample.
Rapid determination of apolipoprotein E genotype using a heteroduplex generator.
Hofman et al., "Apolipoprotein E gene is related to mortality only in normal weight individuals: the Rotterdam Study," European Journal of Epidemiology, vol.
Modulation of apolipoprotein D and apolipoprotein E expression in rat hippocampus after entorhinal cortex lesion.
Apolipoprotein E gene polymorphism: effects on plasma lipids and risk of type 2 diabetes and coronary artery disease.
Apolipoprotein E: Structure-function relationships.
Having the apolipoprotein E [epsilon]4 allele was the second-best predictor, with an odds ratio of 9.2, compared with those without the Alzheimer's disease-associated gene, he said.
The 121 individuals possessing at least one copy of a specific variant of the apolipoprotein E gene, which influences brain-cell repair, performed as well as the rest at age 11.
Also not well understood is the mechanism that underlies the link between the epsilon4 allele of the apolipoprotein E gene and Alzheimer's disease (AD).