• Purity

  >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie? Blue Staining.

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. When Recombinant Human LRPAP is coated at 1 μg/mL (100 μL/well), the concentration of Recombinant Human VLDL R hat produces 50% of the optimal binding response is found to be approximately 5-30 ng/mL.

• Source

  Human embryonic kidney cell, HEK293-derived Thr25-Ser797, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Thr25

• Predicted Molecular Mass

  86 kDa

• SDS-PAGE

  116-142 kDa, reducing conditions

Data Images

Background: VLDL R

Very low density lipoprotein receptor (VLDL R) is a 130 kDa type I transmembrane protein that plays a significant role in lipid metabolism and in nervous system development and function (1). Mature human VLDL R consists of a 770 amino acid (aa) extracellular domain (ECD) with eight tandem LDLR class A repeats, three EGF-like domains, six tandem LDLR class B repeats, and a juxtamembrane region that is rich in O-linked glycosylation; a transmembrane segment, and a 54 aa cytoplasmic domain with one NPxY internalization motif (2). Within the ECD, human VLDLR shares 95% and 92% aa sequence identity with mouse and rat VLDL R, respectively. Alternative splicing of human VLDL R shows a deletion of the O-glycosylated region and also includes a critical determinant for ApoE binding (3, 4). VLDL R is predominantly expressed on endothelial cells lining capillaries and small arterioles (5). VLDL R participates in the tissue uptake of fatty acids from plasma by mediating the internalization of ApoE-containing lipoparticles (  i.e. VLDL, beta -VLDL, and chylomicron remnants) (6). VLDL R binds and internalizes lipoprotein lipase (LPL) and mediates its transport from the basolateral to the lumenal face of endothelial cells (7, 8). VLDL R knockout mice are characterized by reduced LPL activity and increased serum triglyceride clearance (9). VLDL R influences breast cancer cell motility by mediating the uptake of uPAR-PAI1 complexes (7, 10). Lipoprotein accumulation   via macrophage VLDL R is instrumental in promoting the formation of atherosclerotic plaques (11). In the nervous system, VLDL R and ApoE R2 interactions with Reelin are critical for neuronal migration and positioning in the developing brain (12, 13). VLDL R also functions in adult hippocampal synapse maturation, synaptic plasticity, and memory formation (14).

• References:

1. May, P. et al. (2005) Cell. Mol. Life Sci. 62:2325.

2. Sakai, J. et al. (1994) J. Biol. Chem. 269:2173.

3. Iijima, H. et al. (1998) J. Biochem. 124:747.

4. Ruiz, J. et al. (2005) J. Lipid Res. 46:1721.

5. Wyne, K.L. et al. (1996) Arterioscler. Thromb. Vasc. Biol. 16:407.

6. Hauser, P.S. et al. (2011) Prog. Lipid Res. 50:62.

7. Argraves, K.M. et al. (1995) J. Biol. Chem. 270:26550.

8. Obunike, J.C. et al. (2001) J. Biol. Chem. 276:8934.

9. Yagyu, H. et al. (2002) J. Biol. Chem. 277:10037.

10. Webb, D.J. et al. (1999) J. Biol. Chem. 274:7412.

11. van Eck, M. et al. (2005) Atherosclerosis 183:230.

12. Hiesberger, T. et al. (1999) Neuron 24:481.

13. Trommsdorff, M. et al. (1999) Cell 97:689.

14. Weeber, E.J. et al. (2002) J. Biol. Chem. 277:39944.

• Long Name:

  Very Low Density Lipoprotein Receptor

• Entrez Gene IDs:

  7436 (Human); 22359 (Mouse)

• Alternate Names:

  CARMQ1; CHRMQ1; FLJ35024; very low density lipoprotein receptor; very low-density lipoprotein receptor; VLDL R; VLDL receptor; VLDLR; VLDL-R; VLDLRCH