Probable extracellular signal that regulates meristem maintenance. May function as a putative ligand for a receptor complex including FON1. Regulates the size of the floral meristem and the number of floral organs. Expressed in shoot apical and axillary meristems, but not in other vegetative tissues. Detected in a group of small cells at the apical region of the central zone of the meristems. Expressed during the development of the floral organ primordia. No longer detected after the carpel has formed. Enlargement of the floral meristem and increased number of floral organs. Belongs to the CLV3/ESR signal peptide family.