Hu Recom R-Spondin-1, 500 µg

A human recombinant R-Spondin-1 (RSPO1) cytokine supplied by STEMCELL Technologies is produced in CHO cells. R-Spondin-1 is the prototype member of the R-spondin protein subfamily of thrombospondin type 1 repeat (TSR-1)-containing proteins, characterized by a TSR-1 domain, a carboxy-terminal region with positively charged amino acids, and two N-terminal furin-like cysteine-rich repeats. Although RSPO family members cannot themselves initiate signaling, they are potent enhancers of WNT signaling. RSPO1 activates β-catenin signaling via the WNT signaling cascade and indirectly increases low-density lipoprotein receptor-related protein 6 (LRP6) on the cell surface by binding leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5) and competing with the WNT antagonist DKK-1 for binding to the WNT coreceptors Kremen and LRP6. It is involved in pleiotropic roles during embryogenesis, is required for the specification of hematopoietic stem cells, and has been shown to be important in the growth, survival, and migration of ovarian cancer cells.

Also known as hRspo1 and Roof plate-specific Spondin-1 (UniProt accession Q2MKA7), the protein has a predicted molecular mass of 26.8 kDa and is supplied as a lyophilized powder from a sterile-filtered solution containing phosphate-buffered saline. Specific activity is ≥ 2.0 x 10^4 units/mg, determined by luciferase activity in HEK-293 cells in the presence of mouse Wnt-3a, with an EC50 ≤ 50 ng/mL (an example EC50 of 36.4 ng/mL is shown in the product data). Purity is ≥ 95% as assessed by SDS-PAGE under reducing and non-reducing conditions, and endotoxin level is ≤ 1 EU/µg protein as measured by kinetic Limulus amebocyte lysate (LAL) analysis. The product is stable as supplied for 12 months from the date of receipt when stored at -20 to -80°C.

Centrifuge the vial before opening and reconstitute in sterile water to at least 0.1 mg/mL by pipetting the solution down the sides of the vial; do not vortex. Where the reconstituted product will not be used immediately, it can be diluted with concentrated bovine serum albumin (BSA) to a final BSA concentration of 0.1%. As a general guide, stock solutions should not be stored at 2 - 8°C for more than 1 month or at -20 to -80°C for more than 3 months, and repeated freeze-thaw cycles should be avoided. The product is intended for research use only and is not for human or animal diagnostic or therapeutic uses.