Wnt domain found in protein Wnt-5a and similar proteins
Wnt-5a is a secreted growth factor that belongs to the noncanonical members of the Wingless-related MMTV-integration family. It can activate or inhibit canonical Wnt signaling, depending on receptor context. Wnt-5a specifically regulates dendritic spine formation in rodent hippocampal neurons, resulting in postsynaptic development that promotes the clustering of the postsynaptic density protein 95 (PSD-95). Wnt genes have been identified in vertebrates and invertebrates, but not in plants, unicellular eukaryotes, or prokaryotes. In humans, 19 WNT proteins are known. Because of their insolubility little is known about Wnt protein structure, but all have 23 or 24 Cys residues whose spacing is highly conserved. Signal transduction by Wnt proteins (including the Wnt/beta-catenin, the Wnt/Ca++, and the Wnt/polarity pathway) is mediated by receptors of the Frizzled and LDL-receptor-related protein (LRP) families. The Wnt signaling mediated by Wnt proteins that orchestrate and influence a myriad of cellular processes, such as cell proliferation, differentiation, tumorigenesis, apoptosis, and participation in immune defense during microbe infection.
Feature 1:Frizzled receptor binding site [polypeptide binding site]
Evidence:
Comment:The structure of Xenopus Wnt8 (XWnt8) in complex with mouse Frizzled-8 (Fz8) cysteine-rich domain (CRD) reveals an unusual two-domain Wnt structure, not obviously related to known protein folds, resembling a "hand" with "thumb" and "index" fingers extended to grasp the Fz8-CRD at two distinct binding sites.
Comment:Based on the structure of Xenopus laevis Wnt8 (4F0A) in complex with the cysteine-rich domain of frizzled 8.
Jiyao W et al.(2023). "The conserved domain database in 2023.",