RSPO3
Description
The RSPO3 (R-spondin 3) is a protein-coding gene located on chromosome 6.
RSPO3 is a protein encoded by the RSPO3 gene in humans. It belongs to the thrombospondin type 1 repeat gene superfamily and contains a furin-like cysteine-rich region. Furin-like repeat domains are found in various eukaryotic proteins involved in signal transduction by receptor tyrosine kinases. During embryonic development, RSPO3 is expressed in the tail bud and the posterior presomitic mesoderm of the embryo.
RSPO3, also known as R-spondin-3, plays a crucial role in activating the canonical Wnt signaling pathway. It acts as a ligand for LGR4-6 receptors (LGR4, LGR5, or LGR6), promoting their association with phosphorylated LRP6 and frizzled receptors. This triggers the canonical Wnt signaling pathway, resulting in increased expression of target genes. RSPO3 also regulates both the canonical Wnt/beta-catenin-dependent pathway and non-canonical Wnt signaling by inhibiting ZNRF3, a key regulator of the Wnt signaling pathway. It functions as a ligand for frizzled FZD8 and LRP6 and may negatively regulate the TGF-beta pathway. Additionally, RSPO3 acts as a key regulator of angiogenesis by controlling vascular stability and pruning through activation of the non-canonical Wnt signaling pathway in endothelial cells. It can also amplify Wnt signaling independently of LGR4-6 receptors, potentially by acting as a direct antagonistic ligand to RNF43 and ZNRF3.
RSPO3 is also known as CRISTIN1, PWTSR, THSD2.
