Low Density Lipo (LDL) ELISA Kit for Human

The low density lipoprotein receptor (LDLR) gene family consists of cell surface proteins involved in receptor-mediated endocytosis of specific ligands. Low density lipoprotein (LDL) is normally bound at the cell membrane and taken into the cell ending up in lysosomes where the protein is degraded and the cholesterol is made available for repression of microsomal enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, the rate-limiting step in cholesterol synthesis. At the same time, a reciprocal stimulation of cholesterol ester synthesis takes place. Mutations in this gene cause the autosomal dominant disorder, familial hypercholesterolemia. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Sep 2010]

LDLR: Binds LDL, the major cholesterol-carrying lipoprotein of plasma, and transports it into cells by endocytosis. In order to be internalized, the receptor-ligand complexes must first cluster into clathrin-coated pits. In case of HIV-1 infection, functions as a receptor for extracellular Tat in neurons, mediating its internalization in uninfected cells. Defects in LDLR are the cause of familial hypercholesterolemia (FH); a common autosomal semi- dominant disease that affects about 1 in 500 individuals. The receptor defect impairs the catabolism of LDL, and the resultant elevation in plasma LDL-cholesterol promotes deposition of cholesterol in the skin (xanthelasma), tendons (xanthomas), and coronary arteries (atherosclerosis). Belongs to the LDLR family. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Membrane protein, integral; Receptor, misc.; Cell surface

Chromosomal Location of Human Ortholog: 19p13.2

Cellular Component: apical part of cell; basolateral plasma membrane; cell surface; coated pit; early endosome; endosome membrane; external side of plasma membrane; Golgi apparatus; integral to plasma membrane; late endosome; lysosome; membrane; plasma membrane; receptor complex

Molecular Function: calcium ion binding; clathrin heavy chain binding; glycoprotein binding; identical protein binding; low-density lipoprotein binding; low-density lipoprotein receptor activity; protease binding; protein binding; receptor activity; very-low-density lipoprotein receptor activity; viral receptor activity

Biological Process: cholesterol absorption; cholesterol homeostasis; cholesterol metabolic process; cholesterol transport; endocytosis; entry of virus into host cell; fat-soluble vitamin metabolic process; lipid metabolic process; lipoprotein catabolic process; lipoprotein metabolic process; phospholipid transport; phototransduction, visible light; receptor-mediated endocytosis; retinoid metabolic process; vitamin metabolic process

Disease: Hypercholesterolemia, Familial