Ligand for members of the frizzled family of seven transmembrane receptors. Functions in the canonical Wnt/beta-catenin signaling pathway. Expressed from neurula stage onwards. Palmitoleoylation is required for efficient binding to frizzled receptors. Depalmitoleoylation leads to Wnt signaling pathway inhibition. Belongs to the Wnt family. Originally called wnt2 by PubMed:1408135 but it is considered to be a wnt2b paralog by Xenbase.