Transcription factor that specifically binds AT-rich DNA sequences related to the nuclear matrix attachment regions (MARs) (By similarity). Acts redundantly with AHL4 to regulate the formation of tissue boundary between the xylem and procambium in the root meristem (PubMed:23335615). Homodimer. Interacts with AHL4. Expressed in both procambium and xylem precursors of the root meristem. Also detected in the endodermis in the late elongation zone and onwards. The PPC domain mediates interactions between AHL proteins. Misspecification of tissue boundaries between the xylem and procambium.