Transcription activator that recognizes and binds to the DNA consensus sequence 5'-CAC[AG]N[AT]TNCCNANG-3'. Required for the initiation and growth of ovules integumenta, and for the development of female gametophyte. Plays a critical role in the development of gynoecium marginal tissues (e.g. stigma, style and septa), and in the fusion of carpels and of medial ridges leading to ovule primordia. Also involved in organs initiation and development, including floral organs. Maintains the meristematic competence of cells and consequently sustains expression of cell cycle regulators during organogenesis, thus controlling the final size of each organ by controlling their cell number. Regulates INO autoinduction and expression pattern. As ANT promotes petal cell identity and mediates down-regulation of AG in flower whorl 2, it functions as a class A homeotic gene. Interacts with ANL2, HDG2 and HDG10, and possibly with GL2, HDG3, HDG8, ATML1 and PDF2. Mostly expressed in developing flowers. Also present in mature flowers, siliques and seedlings, but not in mature roots, leaves and stems. Expressed in ovules and in vegetative and floral primordia. Expressed in floral primordia, in STM-negative region, then in sepal primordia. As sepal develops, progressively confined to a basal core before disappearing. Present in stamen primordia, then confined to a central region as they become stalked and develop locules. Later reduced to procambial cells as stamen mature. From petal primordia, expressed on the lateral edges of developing petals and finally confined to petal epidermis before disappearing. Present in carpel primordia, then in inner side of carpels especially in the placenta. Strong levels in ovules primordia and young ovules, then localized in integuments initiation zone before being confined to inner integument cells that will differentiate into the endothelium. Expressed in the distal half of the funiculus throughout ovule development and later extends into the chalaza. After fertilization, expression shift to the embryo. First on the apical part at the globular stage, then in cotyledons primordia, and later in cotyledons during the torpedo stage. As cotyledons grow out, expression becomes limited to a plane separating adaxial and abaxial parts. Excluded from the embryonic central region (ECR). In seedlings, found in leaf primordia then in central and lateral actively developing regions of extending leaves. Belongs to the AP2/ERF transcription factor family. AP2 subfamily.