Apolipoprotein E3/ApoE3 Products

Description

Apolipoprotein E (ApoE) is a polymorphic lipid-transport protein with three major human isoforms—ApoE2, ApoE3, and ApoE4—differing by single amino acid substitutions at residues 112 and 158, which significantly alter their structure and function [1, 2].  All isoforms share a two-domain structure: the N-terminal domain mediates receptor binding, while the C-terminal domain facilitates lipid binding and oligomerization [2]. ApoE3 (Cys112/Arg158) is the most common and functionally neutral isoform, while ApoE2 (Cys112/Cys158) has reduced affinity for LDL receptors, often leading to type III hyperlipoproteinemia in homozygotes [1, 4]. ApoE4 (Arg112/Arg158) exhibits a more compact and less stable structure due to domain interaction, predisposing it to pathological effects in the brain [2, 5]. Functionally, ApoE isoforms differentially regulate neuronal metabolism: ApoE2 enhances glycolytic activity and hexokinase expression, promoting neuroprotection, whereas ApoE4 impairs these pathways, increasing vulnerability to aging and Alzheimer's disease (AD) [1]. Recent transcriptomic and epigenomic profiling of human microglia in an AD xenotransplantation model revealed that ApoE isoforms distinctly shape gene expression and chromatin accessibility. ApoE4 drives pro-inflammatory and neurodegenerative signatures, while ApoE2 supports homeostatic microglial states [3]. Clinically, ApoE genotyping is widely used to assess AD risk, with ApoE4 being the strongest genetic risk factor and ApoE2 offering relative protection [4, 5]. Therapeutic strategies targeting ApoE include isoform-specific modulation and gene editing. Additionally, ApoE isoforms are valuable tools in translational research for drug screening, biomarker discovery, and personalized medicine [4].

Bioinformatics

Uniprot	P02649.1
Product By Gene ID	348
Alternate Names	AD2 Apo-E ApoE4 apolipoprotein E Apolipoprotein E3 LDLCQ5 LPG