Qk031 is a specialized form of R-spondin 1 that specifically binds to the LGR5 receptor, which was developed in the lab of Marc de la Roche (University of Cambridge). R-spondin 1 (Qk006) is a ligand for the leucine-rich repeat-containing G-protein coupled receptors (LGR) 4-6. Binding of R-spondin 1 to its coreceptors, LGR4-6 and ZNRF3, releases the inhibition ZNRF3 imposes on wnt signalling.
In epithelial tissues LGR5 marks the stem cell population. This engineered form, R-spondin1 LR5, activates wnt signalling only in the LGR5+ stem cell population.
R-spondin1 LR5 support organoid survival and growth in intestinal organoid culture. As LGR5 specifically marks stem cells and is not found on transit amplifying cells, lower crypt multiplicity is seen in organoid cultures with R-spondin1 LR5 (in comparison with WT R-spondin1), which supports the notion that this engineered form is acting specifically on stem cells.
This is part of our pioneering proteins range where the full range of activities and applications of this novel protein have not been determined.