• Purity

  >90%, by SDS-PAGE under reducing conditions and visualized by silver stain.

• Endotoxin Level

  <0.01 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. Immobilized Recombinant Human EphB3 Fc Chimera at 2 μg/mL (100 μL/well) can bind recombinant mouse Ephrin-B1 Fc Chimera with a linear range of 0.04-2.5 ng/mL

• Source

  Mouse myeloma cell line, NS0-derived Leu38-Ala550

• Accession #

• N-terminal Sequence    
  Analysis

  Leu38

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  82.7 kDa (monomer)

• SDS-PAGE

  90-100 kDa under reducing conditions

Background: EphB3

EphB3, also known as Cek10, Tyro6, Sek4, Hek2, and Mdk5, is a 130 kDa member of the transmembrane Eph receptor tyrosine kinase family. The A and B classes of Eph proteins are distinguished by Ephrin ligand binding preference but have a common structural organization. Eph-Ephrin interactions are widely involved in the regulation of cell migration, tissue morphogenesis, and cancer progression (1). The 526 amino acid (aa) extracellular domain (ECD) of mature human EphB3 contains a ligand binding domain followed by a cysteine rich region and two fibronectin type III domains. The 418 aa cytoplasmic domain contains a tyrosine kinase domain, a sterile alpha motif (SAM), and a PDZ binding motif (2). Within the ECD, human EphB3 shares 96% aa sequence identity with mouse and rat EphB3. Binding of EphB3 to its ligands Ephrin-B1, B2, and B3 triggers forward signaling through EphB3 as well as reverse signaling through the Ephrin (1, 3). EphB3 also interacts   in cis with the receptor tyrosine kinase Ryk (4). Activation of its kinase is required for some but not all of the effects of EphB3 on cellular adhesion, motility, and morphology (5). EphB3 is widely expressed during development and in the adult; it shows a complementary tissue distribution to the Ephrin-B ligands (6-9). EphB3 function is important in vascular, nervous system, thymocyte, and palate development (6, 7, 10-12). It directs embyronic neuronal axon pathfinding, and its up-regulation on local macrophages following neuronal injury promotes the growth of regenerating axons (10, 13). EphB3 inhibits colorectal carcinogenesis and invasion by preventing the migration of tumor cells out of the intestinal crypt (9, 14). In non-small cell lung cancer, however, it is up-regulated and can promote tumor progression (15). EphB3 function is supported by the cooperative action of EphB2 in several of these processes (6, 10-12, 16).

• References:

1. Park, I. and H.S. Lee (2015) Mol. Cells 38:14.

2. Bohme, B. et al. (1993) Oncogene 8:2857.

3. Pasquale, E.B (2004) Nat. Neurosci. 7:417.

4. Trivier, E. and T.S. Ganesan (2002) J. Biol. Chem. 277:23037.

5. Miao, H. et al. (2005) J. Biol. Chem. 280:923.

6. Adams, R.H. et al. (1999) Genes Dev. 13:295.

7. Krull, C.E. et al. (1997) Curr. Biol. 7:571.

8. Willson, C.A. et al. (2006) J. Mol. Histol. 37:369.

9. Cortina, C. et al. (2007) Nature Genet. 39:1376.

10. Birgbauer, E. et al. (2000) Development 127:1231.

11. Alfaro, D. et al. (2008) Immunology 125:131.

12. Risley, M. et al. (2009) Mech. Dev. 126:230.

13. Liu, X. et al. (2006) J. Neurosci. 26:3087.

14. Batlle, E. et al. (2005) Nature 435:1126.

15. Ji, X.-D. et al. (2011) Cancer Res. 71:1156.

16. Holmberg, J. et al. (2006) Cell 125:1151.

• Long Name:

  Eph Receptor B3

• Entrez Gene IDs:

  2049 (Human); 13845 (Mouse)

• Alternate Names:

  Cek10; EC 2.7.10; EC 2.7.10.1; EK2; EPH receptor B3; EphB3; EPH-like kinase 2; EPH-like tyrosine kinase-2; ephrin type-B receptor 3; ETK2Hek2; Hek2; human embryo kinase 2; Mdk5; Sek4; Tyro6; Tyrosine-protein kinase TYRO6