• Purity

  >90%, by SDS-PAGE with silver 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. Immobilized Recombinant Human Vitronectin (Catalog # ) at 1 μg/mL can bind Recombinant Mouse Integrin alpha V beta 3 with an apparent K    _D <5 nM.  

• Source

  Chinese Hamster Ovary cell line, CHO-derived

  Mouse Integrin alpha V (Phe31-Val988) Accession # P43406	His-Pro	GGGSGGGS	Acidic Tail	6-His tag
  Mouse Integrin beta 3 (Glu26-Asp717) Accession # O54890	His-Pro	GGGSGGGS	Basic Tail
  N-terminus				C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Phe31 (Integrin alpha V) & Glu26 (Integrin beta 3)    
     
   

• Structure / Form

  Noncovalently-linked heterodimer

• Predicted Molecular Mass

  115 kDa (Integrin alpha V) & 84.5 kDa (Integrin beta 3)

• SDS-PAGE

  135-145 kDa & 100-115 kDa, reducing conditions

Background: Integrin alpha V beta 3

Integrin alpha V beta 3 together with alpha IIb beta ₃, constitutes the only known beta 3 Integrins (1?3). The non?covalent heterodimer of 170 kDa alpha V/CD51 and 93 kDa beta ₃/CD61 subunits shows wide expression, notably by endothelial cells and osteoclasts (2?4). Each subunit has a transmembrane sequence and a short cytoplasmic tail connected to the cytoskeleton. Active cell surface alpha V beta 3 adheres to matrix proteins including vitronectin, fibronectin, fibrinogen and thrombospondin (2, 3). The ligand binding site of alpha V beta 3 is in the N?terminal head region, formed by interaction of the beta 3 vWFA domain with the alpha V beta-propeller structure (4). The alpha V subunit contributes a thigh and a calf region, while the beta 3 subunit contains a PSI domain and four cysteine?rich I?EGF folds. The alpha V subunit domains termed thigh, calf?1 and calf?2 generate a “knee” region that is bent when the alpha V beta 3 is in its constitutively inactive state. Activation, either by “inside out” signaling or by Mg²⁺ or Mn²⁺ binding, extends the Integrin to expose its ligand binding site (1, 4). The 958 aa mouse alpha V ECD shares 92?95% aa sequence identity with human, rat and bovine  alpha V while the 692 aa mouse beta ₃ ECD shares 95% aa identity with rat and 89?91% with human, canine, equine, bovine and porcine beta ₃. alpha V beta 3 is essential for the maturation of osteoclasts and their binding and resorption of bone; it also, however, promotes their apoptosis (5, 6). M?CSF R and alpha V beta 3 share signaling pathways during osteoclastogenesis, and deletion of either molecule causes osteopetrosis (5, 6). alpha V beta 3 is involved in several other signaling pathways by direct interaction with receptor tyrosine kinases and ligands. For example, it cooperates with endothelial cell VEGF R2 in angiogenesis, and with IGF?1 to promote cancer cell proliferation and invasiveness (7, 8). Also, cell entry of several viruses is mediated by alpha V beta 3 (4, 9).

• References:

1. Hynes, R. O. (2002) Cell 110:673.

2. Serini, G. et al. (2006) Exp. Cell Res. 312:651.

3. Ross, F. P. and S. L. Teitelbaum (2005) Immunol. Rev. 208:88.

4. Xiong, J. et al. (2001) Science 294:339.

5. McHugh, K. P. et al. (2000) J. Clin. Invest. 105:433.

6. Faccio, R. et al. (2003) J. Clin. Invest. 111:749.

7. Somanath, P.R. et al. (2009) Angiogenesis 12:177.

8. Saegusa, J. et al. (2009) J. Biol. Chem. 284:24106.

9. Chu, J. J. and M. Ng (2004) J. Biol. Chem. 279:54533.

• Entrez Gene IDs:

  3685 (Human)

• Alternate Names:

  antigen identified by monoclonal L230; CD51 antigen; CD51; Integrin alpha V beta 3; integrin alpha-V; integrin, alpha V (vitronectin receptor, alpha polypeptide, antigen CD51); MSK8; Vitronectin receptor subunit alpha; VNRADKFZp686A08142