R-Spondin
R-Spondin (R-spondin 1, encoded by RSPO1) is a secreted activator of the canonical Wnt signalling pathway. It acts as a ligand for LGR4, LGR5 and LGR6 receptors and is also known by the aliases RSPONDIN and FLJ40906. Browse Assay Genie's current range of R-Spondin research reagents below, or read on for the biology behind the target.
R-Spondin activates the canonical Wnt signalling pathway by acting as a ligand for the LGR4-6 receptors. Once R-Spondin binds LGR4, LGR5 or LGR6, these receptors associate with phosphorylated LRP6 and with frizzled receptors that have been activated by extracellular Wnt ligands. This triggers canonical Wnt signalling and increases expression of target genes. R-Spondin also acts as a ligand for frizzled FZD8 and LRP6.
R-Spondin additionally regulates Wnt/beta-catenin-dependent and non-canonical Wnt signalling by inhibiting ZNRF3, an important regulator of the pathway. It antagonises DKK1/KREM1-mediated internalisation of LRP6 through an interaction with KREM1, and it may negatively regulate the TGF-beta pathway. UniProt annotates an essential role for the protein in ovary determination.
The RSPO1 gene encodes a secreted protein with two cysteine-rich, furin-like domains and one thrombospondin type 1 domain. UniProt lists both secreted and nuclear locations, and alternative splicing yields multiple transcript variants. In mice, the protein induces rapid onset of crypt cell proliferation and increases intestinal epithelial healing, giving a protective effect against chemotherapy-induced adverse effects. The protein belongs to the R-spondin family, and the gene was previously named R-spondin homolog (Xenopus laevis). The mouse ortholog is Rspo1.
R-Spondin potentiates canonical Wnt signalling through LGR4-6, LRP6 and frizzled receptors, making it central to studies of pathway activation.
Its binding to LGR4, LGR5 and LGR6, FZD8, LRP6 and KREM1 makes it a useful model for Wnt co-receptor complexes.
In mice it induces crypt cell proliferation and improves intestinal epithelial healing, with a protective effect against chemotherapy-induced adverse effects.
UniProt annotates an essential role for R-Spondin in ovary determination, linking Wnt regulation to reproductive development.
R-Spondin is a secreted ligand for LGR4, LGR5 and LGR6 that activates canonical Wnt signalling. Receptor binding leads to association with phosphorylated LRP6 and frizzled receptors. It also inhibits ZNRF3 and antagonises DKK1/KREM1-mediated internalisation of LRP6.
The HGNC name is R-spondin 1 and the gene symbol is RSPO1. Aliases include RSPONDIN and FLJ40906, and the previous name was R-spondin homolog (Xenopus laevis). NCBI notes that alternative splicing produces multiple transcript variants.
A mouse ortholog, Rspo1, is documented, and mouse studies show the protein induces crypt cell proliferation and promotes intestinal epithelial healing. For species reactivity, check the datasheet of any product for its validated reactivity.
Wnt pathway receptors, co-receptors and regulators that interact with R-Spondin, with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q2MKA7; product specifications from Assay Genie datasheets.