Ligand for members of the frizzled family of seven transmembrane receptors (By similarity). Functions in the canonical Wnt signaling pathway that results in activation of transcription factors of the TCF/LEF family (By similarity). Required for normal embryonic development (By similarity). Detected at neurula and tadpole stage. Palmitoleoylation is required for efficient binding to frizzled receptors. Depalmitoleoylation leads to Wnt signaling pathway inhibition. Belongs to the Wnt family.