Wnt-1 is a secreted glycoprotein that binds members of the Frizzled family of seven transmembrane domain receptors. First identified as a proto-oncogene activated in mouse model of mammary tumors, Wnt-1 is known to exert a wide range of functions. Effects of Wnt-1 include control of cell proliferation, patterning, motility, and fate determination. The secretion of Wnt-1 plays an important role in embryonic development and carcinogenesis. Wnt-1 may also affect morphogenesis of the neural tube and in Central Nervous System (CNS) 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.