Frizzled-8 cysteine-rich domain (FZD8 CRD)

The **Frizzled-8 cysteine-rich domain (FZD8 CRD)** is the highly conserved extracellular N-terminal region of the Frizzled-8 receptor, a member of the Frizzled (FZD) family of G protein-coupled receptors that serve as primary receptors for Wnt signaling proteins. This domain is characterized by ten conserved cysteines forming five disulfide bridges, giving it a stable tertiary structure mainly composed of alpha helices[3][4][8]. The FZD8 CRD is essential for binding Wnt ligands, particularly through hydrophobic and electrostatic interactions, facilitating ligand specificity and receptor activation[2][3][6]. Structural studies reveal a distinctive fold not related to other protein domains, with key sites for lipid-modified Wnt proteins (such as Wnt8 or Wnt11) interacting deeply within the domain[2][3]. The domain plays a fundamental role in cellular communication controlling development, cell fate, and tissue patterning, and is disrupted in numerous diseases, especially cancers where aberrant Wnt signaling promotes tumorigenesis and metastasis[7][9]. Targeting the FZD8 CRD and its ligand interactions is therefore of major interest for the development of anti-cancer therapies, regenerative medicine, and disease modulation[1][4][7].

Other names

FZD8-CRDFrizzled-8 CRDFrizzled family receptor 8 cysteine-rich domainMouse Frizzled-8 cysteine-rich domain (when specifying ortholog)

Antagonism/blockade of Wnt ligand binding; Inhibition of downstream Wnt/β-catenin signaling; Prevention of receptor-ligand complex formation; Disruption of co-receptor complex with LRP5/6 or TGF-β receptors (prevents pathway activation)