LDL Receptor, also known as LDLR, is a mosaic protein which belongs to the Low density lipoprotein receptor gene family. The low density lipoprotein receptor (LDLR) gene family consists of cell surface proteins involved in receptor-mediated endocytosis of specific ligands. LDL Receptor consists of 840 amino acids (after removal of signal peptide) and mediates the endocytosis of cholesterol-rich LDL. 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. LDL Receptor is a cell-surface receptor that recognizes the apoprotein B100 which is embedded in the phospholipid outer layer of LDL particles. The receptor also recognizes the apoE protein found in chylomicron remnants and VLDL remnants.
1. Measure by its ability to bind with human PCSK9 in a functional ELISA.Immobilized human PCSK9 at 10 µg/ml (100 ?l/well) can bind biotinylated recombinant human LDLR. The EC50 of biotinylated human LDLR is 0.61 µg/ml.2. Immobilized mouse PCSK9 at 10 µg/ml (100 ?l/well) can bind biotinylated recombinant human LDLR. The EC50 of biotinylated human LDLR is 0.12 µg/ml.
Endotoxin:
<1.0 EU per µg of the protein as determined by the LAL method.
Protein Construction:
A DNA sequence encoding the extracellular domain of human LDLR (NP_000518.1) precursor (Met 1-Arg 788) was expressed with a C-terminal polyhistidine tag.
Purity:
> 85 % as determined by reducing SDS-PAGE.
Mol Mass:
86 kDa
Formulation:
Lyophilized from sterile PBS, pH 7.4
Shipping:
This product is provided as lyophilized powder which is shipped with ice packs.
Stability and Storage:
Lyophilized proteins are stable for up to 12 months when stored at -20 to -80°C. Reconstituted protein solution can be stored at 4-8°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.