• Purity

  >90%, 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 in a competitive binding assay. When rrNeurexin-1 alpha (Catalog # 4485-NX) is immobilized at 1 μg/mL (100 μL/well), rrNeurexophilin-1 inhibits 50% binding of biotinylated rrNeurexophilin-1 (1 μg/mL) at the concentration range of 1-3 μg/mL.

• Source

  Mouse myeloma cell line, NS0-derived Ala22-Gly271 & Arg107-Gly271, both with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Ala22 & Arg107

• Predicted Molecular Mass

  19 kDa & 29.4 kDa

• SDS-PAGE

  27-30 kDa and 42-50 kDa, reducing conditions

Background: Neurexophilin-1

Neurexophilin-1 (NXPH-1) is one of at least four vertebrate neuropeptide-like secreted glycoproteins in the neurexophilin family (1, 2). The 29 kDa, 271 amino acid (aa) NXPH-1 sequence contains a 22 aa signal peptide, a 94 aa propeptide that is cleaved at a basic motif, and a 115 aa mature protein that contains three potential N-glycosylation sites in the N-terminal portion and six conserved cysteines in the C-terminal portion (1). Mature rat NXPH-1 shares 99%, 99%, 99%, 96% and 84% aa identity with mouse, human, bovine, opossum and zebrafish NXPH-1, respectively. NXPH-1 is expressed selectively in subpopulations of neurons within the cerebral cortex, cerebellum and olfactory bulb that are thought likely to be inhibitory interneurons (2, 3). NXPH-3 is the neurexophilin most similar to NXPH-1, sharing 69% aa identity within the mature region. Expression of NXPH-1 and NXPH-3 does not appear to coincide, but both are tightly bound extracellular ligands of alpha -neurexins, synaptic transmembrane molecules that are essential for calcium-triggered neurotransmitter release (1, 4, 5). Genetic deletion of NXPH-1 and/or NXPH-3 produces no anatomical effect, although mice lacking NXPH-3 show defects in motor coordination (4, 6). Of the other known neurexophilins, NXPH-2 is not expressed in rodents, and NXPH-4 does not bind alpha -neurexins (1, 4).

• References:

1. Missler, M. and T. C. Sudhof (1998) J. Neurosci. 18:3630.

2. Petrenko, A. G. et al. (1996) J. Neurosci. 16:4360.

3. Clarris, H. J. et al. (2002) Int. J. Dev. Biol. 46:649.

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

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

6. Beglopoulos, V. et al. (2005) Mol. Cell. Biol. 25:7278.

• Entrez Gene IDs:

  30010 (Human); 18231 (Mouse); 25501 (Rat)

• Alternate Names:

  neurexophilin 1; Neurexophilin1; Neurexophilin-1; NPH1; NXPH1