Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5)

Receptor for R-spondins which potentiates the canonical Wnt signaling pathway and functions as a stem cell marker of the intestinal epithelium and the hair follicle. Upon binding to R- spondins (RSPO1, RSPO2, RSPO3 or RSPO4), associates with phosphorylated LRP6 and frizzled receptors which are activated by extracellular Wnt receptors, triggering the canonical Wnt signaling pathway to improve expression of target genes.

In contrast to classical G-protein coupled receptors, does not activate heterotrimeric G-proteins to transduce the signal. Involved in the development and/or maintenance of the adult intestinal stem cells during postembryonic development.