Involved, partially redundantly with VCC/DEAL1 and DEAL3, to ensure bilateral symmetry development and early leaf margin patterning, probably via the regulation of auxin and CUC2 distribution. Mainly expressed in roots, inflorescences and developing leaves, and, at low levels, in mature leaves. Developmental defects of pistils, some being bent or coiled or twisted, and some showing unfused carpels with exposed ovules (PubMed:29139551). The vcc-3 deal2-1 double mutant shows leaf asymmetry (PubMed:29139551). The vcc-3 deal2-1 deal3-1 triple mutant shows a strong leaf asymmetry (PubMed:29139551). Belongs to the DESIGUAL family.