Boundaries that join lateral organs to the plant body are an important determinant of plant architecture. These specialized junctions originate within the shoot apex and control leaf shape, branching architecture, and abscission. Boundary patterning relies on a pair of BTB-ankyrin co-transcription factors encoded by BLADE-ON-PETIOLE1 and 2 (BOP1/2). Members of this class bind to DNA indirectly, by interacting with other types of transcription factors, especially TGACG-motif binding (TGA) basic leucine zipper proteins. My works shows a previously undiscovered role for clade III TGA factors, previously associated with plant defense, in BOP-dependent plant development. This work uncovers a dual role for clade III TGAs in development and defense.