• 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 Neuroligin 1/NLGN1 Variant 2 is immobilized at 5.0 μg/mL, Recombinant Human Neurexin 1 beta Fc Chimera (Catalog # 5268‑NX) binds with an apparent K    _D < 30 nM.

• Source

  Mouse myeloma cell line, NS0-derived Met1-Ser677, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  No results obtained: Gln46 predicted, sequencing might be blocked

• Predicted Molecular Mass

  71.3 kDa

• SDS-PAGE

  90-110 kDa, reducing conditions

Background: Neuroligin 1/NLGN1

Neuroligin 1 (NLGN1 or NL1) is one of several type I transmembrane Neuroligin proteins that play an important role in synaptic development (1). Mature human Neuroligin 1 is an N- and O-glycosylated 120 kDa molecule that consists of a 649 amino acid (aa) extracellular domain (ECD) with a catalytically inactive cholinesterase-like domain, a 21 aa transmembrane segment, and a 125 aa cytoplasmic tail (2). In rat, insertion of 20 aa at splice site A and/or 9 aa at splice site B within the ECD results in NLGN1A, NLGN1B, or NLGN1AB isoforms while the NLGN1(-) isoform has neither insertion (3). This recombinant protein lacks the splice site A insert but contains the splice site B insert and corresponds to the human equivalent of rat NLGN1B. Within the ECD, human NLGN1A shares 99% aa sequence identity with comparable regions of mouse and rat Neuroligin 1, respectively. Neuroligin 1 expression is restricted to postsynaptic nerve terminal membranes where it associates into dimers and tetramers (5 ‑ 7). NLGN1B and NLGN1AB are enriched at excitatory (glutamatergic) contacts, whereas NLGN1A is enriched at inhibitory (GABAergic) contacts and NLGN1(-) is expressed at both (3). The interaction of Neuroligin 1 with presynaptic membrane Neurexins promotes the maturation of presynaptic as well as postsynaptic structures (3, 4, 8 ‑ 11). Neuroligin 1 isoforms are selective in which Neurexin isoforms they bind: NLGN1B and NLGN1AB preferentially interact with Neurexin 1 beta lacking the splice site 4 insert, while NLGN1A and NLGN1(-) bind Neurexin 1 alpha and Neurexin 1 beta irrespective of the SS4 insert (12). Neurexin 1 beta (-SS4) additionally binds to LRRTM2 to trigger a second mechanism that promotes excitatory synapse development (13, 14). Neuroligin 1 mediated synaptogenesis is also enhanced by its direct binding to Thrombospondin 1 (15).

• References:

1. Sudhof, T.C. (2008) Nature 455:903.

2. Ichtchenko, K. et al. (1995) Cell 81:435.

3. Chih, B. et al. (2006) Neuron 51:171.

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

5. Comoletti, D. et al. (2006) Biochemistry 45:12816.

6. Berninghausen, O. et al. (2007) J. Neurochem. 103:1855.

7. Song, J.-Y. et al. (1999) Proc. Natl. Acad. Sci. 96:1100.

8. Wittenmayer, N. et al. (2009) Proc. Natl. Acad. Sci. 106:13564.

9. Jung, S.-Y. et al. (2010) Proc. Natl. Acad. Sci. 107:4710.

10. Chubykin, A.A. et al. (2007) Neuron 54:919.

11. Chih, B. et al. (2005) Science 307:1324.

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

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

14. Ko, J. et al. (2009) Neuron 64:791.

15. Xu, J. et al. (2010) Nat. Neurosci. 13:22.

• Entrez Gene IDs:

  22871 (Human); 192167 (Mouse); 116647 (Rat)

• Alternate Names:

  EC 3.1.1; EC 3.1.1.1; KIAA1070neuroligin-1; MGC45115; Neuroligin 1; NL1; Nlg; NLGN1