Wnt-7b is a secreted, glycosylated member of the Wnt family of developmental proteins. It is considered a class 3 Wnt based on its inability to transform C57MG cells. Wnt-7b is produced by mammary duct epithelium. A role for Wnt-7b has been suggested in cartilage destruction during osteoarthritis. Wnt-7b signaling may also impact the development of the central nervous system (CNS). Mature human Wnt-7b is 99% amino acid (aa) identical to mature mouse and rat Wnt-7b, and 80% identical to Wnt-7a.
The Wnts make up a large family of secreted proteins with roles in pattern formation, cell fate decision, axon guidance, and tumor formation. Wnt family members vary in length between 350 and 400 aa, possess 22 to 24 conserved cysteines, are highly hydrophobic, and show 20 - 85% aa identity within the Wnt family. In general, there are three signaling pathways associated with Wnt-receptor interaction. The first is commonly called the canonical pathway and ultimately culminates in beta-Catenin accumulation and TCF/LEF-1-mediated gene transcription. The other two less well-defined non-canonical pathways include the Wnt/Ca2+ pathway and the planar cell polarity (PCP) pathway.