Probable transcription factor. Widely expressed. Expressed 3 day after germination (DAG) in first rosette leaf primordia around the veins in the apical part of the leaf and close to the midvein in the basal part of the leaf. At later stage, expressed in new forming veins, and veins and fascicular cambium of mature leaves. By auxin. Belongs to the HD-ZIP homeobox family. Class I subfamily.