Secreted Frizzled Related Proteins (sFRP)

Secreted Frizzled related proteins are secreted glycoproteins with homology to the Wnt-binding domain of the Frizzled family of transmembrane receptors. sFRPs contain an N-terminal Frizzled-like cysteine-rich domain (CRD) with 10 conserved cysteines and a C-terminal heparin-binding region. sFRPs function as soluble antagonists of Wnt signaling by binding directly to Wnt proteins and preventing their interactions with Frizzled receptors.