Ligand for members of the frizzled family of seven transmembrane receptors. Functions in the canonical Wnt/beta-catenin signaling pathway. Expressed maternally in both vegetal and animal blastomeres with enrichment in the animal hemisphere. Expressed zygotically near the prosencephalic-mesencephalic boundary of the developing brain in neurula and tailbud stages, and also in non-brain areas at tadpole stages. Expressed both maternally and zygotically. Expression accumulates from stage 17 (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 wnt-2b by PubMed:9203142. Although PubMed:12084573 renames it as wnt-2, it is considered to be a wnt2b paralog by Xenbase.