• Purity

  >90%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie? Blue Staining.

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to induce Topflash reporter activity in HEK293T human embryonic kidney cells. The ED    ₅₀ for this effect is 1-4 ng/mL in the presence of 5 ng/mL Recombinant Mouse Wnt?3a (Catalog # ).

• Source

  Chinese Hamster Ovary cell line, CHO-derived Arg31-Ala263

• Accession #

• N-terminal Sequence    
  Analysis

  Arg31

• Predicted Molecular Mass

  25.6 kDa

• SDS-PAGE

  39 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.

Data Images

Background: R-Spondin 1

R-Spondin 1 (RSPO1, Roof plate-specific Spondin 1), also known as cysteine-rich and single thrombospondin domain containing protein 3 (Cristin 3), is a 27 kDa secreted protein that shares ~40% amino acid (aa) identity with three otherR-Spondin family members (1, 2). All R-Spondins regulate Wnt/ beta -catenin signaling, but have distinct expression patterns (1-3). Like other R-Spondins, R-Spondin 1 contains two adjacent cysteine-rich furin-like domains (aa 34-135) with one potential
N-glycosylation site, followed by a thrombospondin (TSP-1) motif (aa 147-207) and a region rich in basic residues (aa 211-263). Only the furin-like domains are needed for beta -catenin stabilization (2, 4). A putative nuclear localization signal at the C-terminus may allow some expression in the nucleus (5). Potential isoforms of 200 and 236 aa have an alternate, shorter N-terminus or are missingaa 146-208, respectively (6). Over aa 21-263, human R-Spondin 1 shares 89%, 87%, 92%, 91%, 91% and 89% aa identity with mouse, rat, equine, canine, caprine and bovine RSPO-1, respectively. R-Spondin 1 is expressed in early development at the roof plate boundary and is thought to contribute to dorsal neural tube development (3, 5). In humans, rare disruptions of the R-Spondin 1 gene are associated with tendencies for XX sex reversal (phenotypic male) or hermaphroditism, indicating a role for R-Spondin 1 in gender-specific differentiation (7, 8). Disruption is also associated with palmoplantar keratosis (7, 8). Postnatally,R-Spondin 1 is expressed by neuroendocrine cells in the intestine, adrenal gland and pancreas, and by epithelia in kidney and prostate (9). Injection of recombinant R-Spondin 1 in mice causes activation of beta -catenin and proliferation of intestinal crypt epithelial cells, and ameliorates experimental colitis (9, 10). R-Spondin 1 regulates Wnt/ beta -catenin by competing with the Wnt antagonist DKK-1 for binding to the Wnt co-receptors, Kremen and LRP-6, reducing their DKK-1-mediated internalization (11). Reports differ on whether R-Spondin 1 binds LRP-6 directly (11-13).

• References:

1. Chen, J-Z. et al. (2002) Mol. Biol. Rep. 29:287.

2. Kim, K.-A. et al. (2006) Cell Cycle 5:23.

3. Nam, J.-S. et al. (2007) Gene Expr. Patterns 7:306.

4. Kazanskaya, O. et al. (2004) Dev. Cell 7:525.

5. Kamata, T. et al. (2004) Biochim. Biophys. Acta 1676:51.

6. Entrez accession # EAX07331, ABA54598.

7. Tomaselli, S. et al. (2008) Hum. Mutat. 29:220.

8. Parma, P. et al. (2006) Nat. Genet. 38:1304.

9. Kim, K.-A. et al. (2005) Science 309:1256.

10. Zhao, J. et al. (2007) Gastroenterology 132:1331.

11. Binnerts, M.E. et al. (2007) Proc. Natl. Acad. Sci. USA 104:14700.

12. Nam, J.-S. et al. (2006) J. Biol. Chem. 281:13247.

13. Wei, Q. et al. (2007) J. Biol. Chem. 282:15903.

• Long Name:

  Roof Plate-specific Spondin 1

• Entrez Gene IDs:

  284654 (Human); 192199 (Mouse)

• Alternate Names:

  Cristin 3; CRISTIN3; FLJ40906Roof plate-specific spondin-1; hRspo1; roof plate-specific spondin; RSPO; RSPO1; RSpondin 1; R-Spondin 1; R-spondin homolog (Xenopus laevis); RSPONDIN; R-spondin1; R-spondin-1