Development of Functional Microfold (M) Cells from Intestinal Stem Cells in Primary Human Enteroids.
Authors: Rouch J, Scott A, Lei N, Solorzano-Vargas R, Wang J, Hanson E, Kobayashi M, Lewis M, Stelzner M, Dunn J, Eckmann L, Martin M
PLoS ONE, 2016;11(1):e0148216.
Species: Human
Sample Type: Whole Cells
Application: Bioassay
Therapeutic Targeting of Tumor-Derived R-Spondin Attenuates beta-Catenin Signaling and Tumorigenesis in Multiple Cancer Types.
Authors: Chartier C, Raval J, Axelrod F, Bond C, Cain J, Dee-Hoskins C, Ma S, Fischer M, Shah J, Wei J, Ji M, Lam A, Stroud M, Yen W, Yeung P, Cancilla B, O'Young G, Wang M, Kapoun A, Lewicki J, Hoey T, Gurney A
Cancer Res, 2016;76(3):713-23.
Species: Mouse
Sample Type: In Vivo
Application: Bioassayantibod
Intestinal enteroids model GUCY2C-dependent secretion induced by heat-stable enterotoxins
Infect Immun, 2016;0(0):.
Species: Human
Sample Type: Whole Tissue
Application: Bioassay
Novel Bi-specific Domain Antibody to LRP6 Inhibits Wnt and R-spondin Ligand-induced Wnt Signaling and Tumor Growth
Mol Cancer Res, 2016;0(0):.
Species: Human
Sample Type: Whole Cells
Application: Bioassay
Characterization and propagation of tumor initiating cells derived from colorectal liver metastases: trials, tribulations and a cautionary note.
Authors: James M, Howells L, Karmokar A, Higgins J, Greaves P, Cai H, Dennison A, Metcalfe M, Garcea G, Lloyd D, Berry D, Steward W, Brown K
PLoS ONE, 2015;10(2):e0117776.
Species: Human
Sample Type: Whole Cells
Application: Bioassay
Luminal microbes promote monocyte-stem cell interactions across a healthy colonic epithelium.
Authors: Skoczek D, Walczysko P, Horn N, Parris A, Clare S, Williams M, Sobolewski A
J Immunol, 2014;193(1):439-51.
Species: Human
Sample Type: Whole Tissue
Application: Bioassay
Widespread potential for growth-factor-driven resistance to anticancer kinase inhibitors.
Authors: Wilson TR, Fridlyand J, Yan Y, Penuel E, Burton L, Chan E, Peng J, Lin E, Wang Y, Sosman J, Ribas A, Li J, Moffat J, Sutherlin DP, Koeppen H, Merchant M, Neve R, Settleman J
Nature, 2012;487(7408):505-9.
Species: Human
Sample Type: Whole Cells
Application: Bioassay
Role of Gadd45a in Wip1-dependent regulation of intestinal tumorigenesis.
Cell Death Differ., 2012;19(11):1761-8.
Species: Human
Sample Type: Whole Cells
Application: Bioassay
ZNRF3 promotes Wnt receptor turnover in an R-spondin-sensitive manner.
Authors: Hao HX, Xie Y, Zhang Y, Charlat O, Oster E, Avello M, Lei H, Mickanin C, Liu D, Ruffner H, Mao X, Ma Q, Zamponi R, Bouwmeester T, Finan PM, Kirschner MW, Porter JA, Serluca FC, Cong F
Nature, 2012;485(7397):195-200.
Species: Human
Sample Type: Whole Cells
Application: Bioassay
Directed differentiation of human pluripotent stem cells into intestinal tissue in vitro.
Authors: Spence JR, Mayhew CN, Rankin SA
Nature, 2011;470(7332):105-9.
Species: Human
Sample Type: Whole Cells
Application: Bioassay

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).

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.

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.