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. In case of HIV-1 infection, it functions as a receptor for extracellular Tat in neurons, mediating its internalization in uninfected cells. PCSK9 binds to the epidermal growth factor-like repeat A (EGF-A) domain of LDLR, inducing LDLR degradation.
Immunogen Region
22-788(end)
Tag
C-terminal FLAG and Avi tags
Description
Human low density lipoprotein receptor (LDLR), also known as FH, FHC, and LDLCQ2, GenBank Accession No. NM_000527, a.a. 22-788(end), with C-terminal FLAG and Avi tags, MW=87.7 kDa, expressed in an HEK293 cell expression system and enzymatically biotinylated using Avitag technology.
Formulation
40 mM Tris-HCl, pH 8.0, 110 mM NaCl, 2.2 mM KCl, and 20% glycerol.
Species
Human
Application
Useful for studying protein binding and screening small molecules for drug discovery.
Notes
Coat a plate with 100 ng of PCSK9. Add a 25 uL reaction mix (50 mM HEPES pH 7.4, 50 mM NaCl, 200 uM CaCl2, 0.05% Tween, 0.1% BSA, and up to 200 ng LDLR-biotin) to the coated wells and incubate for 2 hr. Add Streptavidin-HRP labeled antibody and incubate 1 hr. Finally, add HRP chemiluminescent substrates and read luminescence.
Note: LDLR is heavily glycosylated, resulting in higher molecular weight. The two bands shown correspond to differing states of glycosylation. Avoid freeze/thaw cycles.
GenBank
NM_000527
Mw(kda)
87.7 kDa
Synonyms
FH, FHC, LDLR, LDLCQ2, low density lipoprotein receptor
Uniprot
P01130
Shipping Temperature
-80°C (dry ice)
Format
Aqueous buffer solution
Storage
At least 6 months at -80°C.
Reference
1. Holla, L., et al., BMC Cell Biol. 2007 Mar 1,8:9. 2. Qian, YW., et al., J Lipid Res. 2007 Jul,48(7):1488-98. 3. Fasano, T., et al., Athersclerosis. 2009 Mar,203(1):166-71.