Involved in the dorsovental asymmetry of flowers. Retards growth rate and reduces organ number in the dorsal region of flowers. Binds specifically to the DNA sequence 5'-GGNCCCNC-3', and is able to bind to the RAD promoter sequence in vivo. First observed in a dorsal domain of floral meristems, prior to any morphological dorsoventral asymmetry. Later expressed in dorsal organ primordia.