Probable transcription factor. Functions with SEPALLATA1/AGL2 and SEPALLATA3/AGL9 to ensure proper development of petals, stamens and carpels and to prevent the indeterminate growth of the flower meristem. Forms a heterodimer via the K-box domain with AG, that could be involved in genes regulation during floral meristem development. Heterodimer with AGAMOUS capable of binding to CArG-box sequences (PubMed:9418042). Interacts with TT16/AGL32 (PubMed:16080001). Expressed early during flower development. Triple mutations in the SEP1, SEP2 and SEP3 genes result in the replacement of the stamens and petals by sepals and of the carpels by a new mutant flower with sepaloid organs.