Probable transcription factor (By similarity). Involved in spikelet transition. Together with IDS1, controls synergistically inflorescence architecture and floral meristem establishment via the regulation of spatio-temporal expression of B- and E-function floral organ identity genes in the lodicules and of spikelet meristem genes. Prevents lemma and palea elongation as well as grain growth. Regulates the transition from spikelet meristem to floral meristem, spikelet meristem determinancy and the floral organ development (By similarity). May form homodimer (By similarity). Interacts with TPR2/ASP1 (By similarity). Belongs to the AP2/ERF transcription factor family. AP2 subfamily.