Probable transcriptional regulator essential for petal development. Required for the early development of the organ primordia of the second whorl. Acts downstream of AP1 and PTL. Strongly expressed in inflorescences and flowers, and weakly in siliques, seedlings and roots. In flowers, it is expressed in petal primordia and their precursor cells. Also expressed in the lateral root caps and the basal cells of lateral roots. Not expressed in the inflorescence meristem or in the flowers at stages 1 and 2. First expressed in the precursor cells of petal primordia in stage 3 flowers and in the developing petal primordia up to stage 6. Not expressed at later stages. Contains a slightly degenerated ERF-associated amphiphilic repression (EAR) motif, which may be involved in the activity of transcriptional repression.