• 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 Draxin is immobilized at 2 μg/mL, Recombinant Human LRP-6 Fc Chimera (Catalog # 1505-LR) binds with an apparent K_D < 25 nM.

  Also measured by its ability to enhance neurite outgrowth of E16-E18 rat embryonic cortical neuron.

• Source

  Mouse myeloma cell line, NS0-derived Gly26-Val349, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Gly26

• Structure / Form

  Monomer

• Predicted Molecular Mass

  36.9 kDa

• SDS-PAGE

  50-60 kDa, reducing conditions

Carrier Free

What does CF mean?

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

What formulation is right for me?

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: Draxin

Draxin (Dorsal repulsive axon guidance protein) also called neucrin (neural tissue-specific cysteine-rich protein) is a secreted, 58 kDa, presumably glycosylated member of the draxin family of repulsive guidance proteins (1 ‑ 5). In mammals, it is expressed in developing neurons (axons), astroglia, and likely cells of the developing somite (1 ‑ 3). Its expression appears to be limited to the brain and spinal cord (2, 4). Human Draxin mRNA encodes 349 amino acids (aa) that include a 25 aa signal sequence and a 324 aa mature, secreted protein containing one potential N-linked glycosylation site followed by a Cys-rich domain (aa 274 ‑ 333). The pattern of cysteines is similar to the second of two cysteine-rich regions in members of the DKK family of Wnt inhibitors (4). Mature human Draxin (aa 26 ‑ 349) shares 80%, 79%, 88% and 86% aa identity with mature mouse, rat, equine and bovine Draxin, respectively. Draxin is a repulsive guidance molecule that, like DKKs, acts as a Wnt antagonist by binding to LRP6 (4). Draxin is expressed by midline glial cells that act as intermediate guideposts for corpus callosum axons (1).  Inactivation of the mouse Draxin gene results in lack of organization of axons into functional tracts or bundles (fasciculation), and failure of the corpus callosum, hippocampal and anterior commissures to form and cross the midline (1). Draxin-deficient mice also show abnormally small hippocampi, especially within the dentate gyrus, where excess apoptosis is detected during early postnatal life (3). In vitro, Draxin blocks migration of chick neural crest cells, while in vivo, ectopic over-expression inhibits growth of mouse axons or causes their misrouting (1, 2, 5).

• References:

1. Islam, S.M. et al. (2009) Science 323:388.

2. Su, Y. et al. (2009) Dev. Growth Differ. 51:787.

3. Zhang, S. et al. (2010) Neurosci. Res. 66:53.

4. Miyake, A. et al. (2009) Biochem. Biophys, Res. Commun. 390:1051.

5. Naser, I.B. et al. (2009) Dev. Biol. 332:351.

• Long Name:

  Dorsal Repulsive Axon Guidance Protein

• Entrez Gene IDs:

  374946 (Human); 70433 (Mouse); 691317 (Rat)

• Alternate Names:

  AGPA3119; C1orf187; chromosome 1 open reading frame 187; dorsal inhibitory axon guidance protein; Dorsal repulsive axon guidance protein; Draxin; FLJ34999; MGC117222; Neucrin; UNQ3119