Acts as a ventralizing factor during embryogenesis. Inhibits axin-mediated JNK activation by binding axin and disrupting axin homodimerization. This in turn antagonizes a Wnt/beta-catenin-independent dorsalization pathway activated by axin/JNK-signaling. At 24 hours post-fertilization, expressed in most tissues, with strongest expression in the brain and somites. Expressed both maternally and zygotically. Belongs to the AIDA family.