Human R-Spondin 1 recombinant protein is purified from a mammalian culture system which can be usd for cell culture work and , which is encoded by the RSPO1 gene, is a secreted protein with a predicted molecular weight of 28kDa. It consists of two cysteine-rich, furin-like domains and one thrombospondin type 1 domain. It is the ligand for the orphan receptor leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) and play a critical role in the RSPO1/WNT4/β-catenin signaling pathway.