Chylomicron remnants (CRs) are "sieved" when they arrive at the liver by size, the appropriate sized remnants passing through the space of Disse. Once inside, CRs containing all-trans-retinyl esters (atREs) can be directly and rapidly taken up by liver parenchymal cells via the low-density lipoprotein receptor (LDLR) using apolipoprotein E (apoE) as a ligand. Internalization of remnants occur via endocytosis (see review D'Ambrosio et al. 2011). This reaction is inferred from uptake studies in mice (Yu et al. 2000). Defects in LDLR cause familial hypercholesterolemia (FH, MIM:143890), a common autosomal disease that affects about 1 in 500 people in most countries. Abnormal LDLR doesn't remove LDL from circulation resulting in high levels of LDL in blood, leading to early cardiovascular disease via atherosclerosis. The defect was first described by Brown and Goldstein (1974).
Chen, W, Cooper, AD, Yu, KC, Jiang, Y
low-density lipoprotein particle receptor activity of LDLR [plasma membrane]
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