Wnt-2b (also known as Wnt-13) is a member of the large and highly conserved Wnt family of secreted, cysteine-rich glycoprotein signaling molecules. Wnt proteins are associated with developmental and carcinogenic processes. Wnt-2b may be necessary to maintain stem cells in an undifferentiated state. As a type II transmembrane protein with a long C-terminal extracellular and a short N-terminal cytoplasmic domain, Wnt-2b is thought to be cleaved within its extracellular region to release the secreted form. It is known that Wnt-2b is expressed in ovarian surface epithelium. Wnt-2b has also been shown to be involved in ureter branching during kidney development.
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 amino acids (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.