• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• 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 Neurexin 2 alpha /NRXN2a Fc Chimera is coated at 2 μg/mL, biotinylated recombinant rat NXPH-1 binds with an apparent K_D <10 nM.

• Source

  Chinese Hamster Ovary cell line, CHO-derived

  Human Neurexin 2 alpha (Met1 - Thr1566) Accession # NP_620060	IEGRMD	Human IgG1 (Pro100 - Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Leu29

• Structure / Form

  Disulfide-linked homodimer    
   

• Predicted Molecular Mass

  193 kDa (monomer)

• SDS-PAGE

  200-250 kda, reducing conditions

Background: Neurexin 2 alpha/NRXN2a

Neurexin 2, also known as NRXN2, is a neuronal type I transmembrane molecule that is encoded by one of three Neurexin genes (1, 2). Mature human Neurexin 2 alpha is an approximately 200 kDa N- and O‑glycosylated protein with a 1608 amino acid (aa) extracellular domain (ECD) and a 55 aa cytoplasmic domain. The ECD contains six LNS domains interspersed with three EGF-like domains and a juxtamembrane O‑glycosylation region (1 ‑ 3). The ECD of human Neurexin 2 alpha shares 98% and 99% aa sequence identity with mouse and rat Neurexin 2 alpha, respectively. Transcription of the Neurexin 2 gene from an internal promoter gives rise to Neurexin 2 beta which lacks the first five LNS domains and all of the EGF-like domains (3, 4). Human Neurexin 2 alpha is combinatorially spliced at five canonical sites in the ECD, giving rise to nearly 200 potential isoforms (4). This recombinant protein (isoform 2 according to SwissProt # Q9P2S2) does not contain inserts at splice sites 1, 2, 3,or 4. Neurexin 2 alpha is primarily expressed in the brain where it is localized to presynaptic terminals (3, 5, 6). It binds Neurexophilin 1 and 3, Neuroligin 2, and Dystroglycan (7 ‑ 9). Only Neurexin 2 isoforms that lack the insert at splice site 4 additionally bind LRRTM2 (10). The interaction between Neurexins and Neuroligins is complex and is restricted to particular combinations of splice forms of each binding partner (11). These interactions promote the differentiation and maintenance of postsynaptic GABA and NMDA but not AMPA terminals (8, 12). At presynaptic terminals as well as in pituitary melanotrophs, alpha Neurexins are required for coupling voltage-dependent calcium channel signaling to neurotransmitter or hormone release (13 ‑ 15).

• References:

1. Craig, A.M. and Y. Kang (2007) Curr. Opin. Neurobiol. 17:43.

2. Lise, M.-F. and A. El-Husseini (2006) Cell. Mol. Life Sci. 63:1833.

3. Ushkaryov, Y.A. et al. (1992) Science 257:50.

4. Rowen, L. et al. (2002) Genomics 79:587.

5. Dean, C. et al. (2003) Nat. Neurosci. 7:708.

6. Ullrich, B. et al. (1995) Neuron 14:497.

7. Missler, M. et al. (1998) J. Biol. Chem. 273:34716.

8. Kang, Y. et al. (2008) J. Biol. Chem. 283:2323.

9. Sugita, S. et al. (2001) J. Cell Biol. 154:435.

10. Siddiqui, T.J. et al. (2010) J. Neurosci. 30:7495.

11. Boucard, A.A. et al. (2005) Neuron 48:229.

12. Kattenstroth, G. et al. (2004) Proc. Natl. Acad. Sci. 101:2607.

13. Missler, M. et al. (2003) Nature 423:939.

14. Zhang, W. et al. (2005) J. Neurosci. 25:4330.

15. Dudanova, I. et al. (2006) J. Neurosci. 26:10599.

• Entrez Gene IDs:

  9379 (Human)

• Alternate Names:

  Neurexin 2 alpha 2; NRXN2