• Purity

  >95%, 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 ability to inhibit proliferation of PC‑3 human prostate cancer cells. The ED    ₅₀ for this effect is 2.5-10 ng/mL.

• Source

  Mouse myeloma cell line, NS0-derived

  Mouse Ephrin-A5 (Met1-Asn203) Accession # NP_997537	IEGRMDP	Mouse IgG2A (Glu98-Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  No results obtained: Gln21 predicted, sequencing might be blocked

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  48.4 kDa (monomer)

• SDS-PAGE

  57-60 kDa, reducing conditions

Background: Ephrin-A5

Ephrin‑A5, also known as AL‑1, RAGS, and LERK‑7, is an approximately 25 kDa member of the Ephrin‑A family of GPI‑anchored ligands that bind and induce the tyrosine autophosphorylation of Eph receptors. Ephrin‑A ligands are structurally related to the extracellular domains of the transmembrane Ephrin‑B ligands. Eph‑Ephrin interactions are widely involved in the regulation of cell migration, tissue morphogenesis, and cancer progression (1, 2). Ephrin‑A5 preferentially interacts with receptors in the EphA family but also with EphB2 (3). Mature mouse Ephrin‑A5 shares 98.9% and 99.5% aa sequence identity with human and rat Ephrin‑A5 (4). Alternate splicing of mouse Ephrin‑A5 generates a short isoform that lacks 27 amino acids in the juxtamembrane region. The short isoform retains the ability to bind EphA3 and inhibit neurite extension (5). Ephrin‑A5 is expressed in multiple tissues during development, particularly in the brain (6, 7). It can exert repulsive or attractive effects on migrating neurons in the developing brain and motor column of the spinal cord (7‑11). Ephrin‑A5 repels migrating axons by inducing growth cone collapse and neurite retraction and by inhibiting the neurotrophic effects of NGF and BDNF (3, 12, 13). It interacts   in cis with EphA3 on retinal axon growth cones which reduces axonal sensitivity to Ephrin‑A5   in trans (14). In the adult, Ephrin‑A5 is expressed on hippocampal neurons and astrocytes and induces the development of hippocampal synapses (10, 15, 16). It supports the proliferation of neural progenitors and the survival of newly differentiated neurons (15). Ephrin‑A5 functions as a tumor suppressor and its normal function in inhibiting EGFR signaling is compromised by its down‑regulation in glioma (17). Ephrin A5 is also down‑regulated in prostate cancer (18). Ephrin‑A5 is expressed by muscle precursor cells and interacts with EphA4 to restrict their migration to the correct locations during forelimb morphogenesis (19).

• References:

1. Miao, H. and B. Wang (2009) Int. J. Biochem. Cell Biol. 41:762.

2. Pasquale, E.B. (2010) Nat. Rev. Cancer 10:165.

3. Himanen, J.-P. et al. (2004) Nat. Neurosci. 7:501.

4. Flenniken, A.M. et al. (1996) Dev. Biol. 179:382.

5. Lai, K.-O. et al. (1999) FEBS Lett. 458:265.

6. Deschamps, C. et al. (2010) BMC Neurosci. 11:105.

7. Cooper, M.A. et al. (2009) Dev. Neurobiol. 69:36.

8. Frisen, J. et al. (1998) Neuron 20:235.

9. Zimmer, G. et al. (2008) Eur. J. Neurosci. 28:62.

10. Otal, R. et al. (2006) Neuroscience 141:109.

11. Eberhart, J. et al. (2004) J. Neurosci. 24:1070.

12. Munoz, L.M. et al. (2005) Dev. Biol. 283:397.

13. Meier, C. et al. (2011) PLoS ONE 6:e26089.

14. Carvalho, R.F. et al. (2006) Nat. Neurosci. 9:322.

15. Hara, Y. et al. (2010) Stem Cells 28:974.

16. Akaneya, Y. et al. (2010) PLoS ONE 5:e12486.

17. Li, J.-J. et al. (2009) Oncogene 28:1759.

18. Gustavsson, H. et al. (2008) Prostate 68:161.

19. Swartz, M.E. et al. (2001) Development 128:4669.

• Entrez Gene IDs:

  1946 (Human); 13640 (Mouse)

• Alternate Names:

  AF1; AL-1; EFL-5; EFNA5; EPH-related receptor tyrosine kinase ligand 7; EphrinA5; Ephrin-A5; EPLG7; GLC1M; LERK-7; LERK7EFL5; RAGS