Transcription factor which acts with the selector homeodomain proteins altering the regulation of downstream target genes such as wingless (wg), teashirt (tsh) and decapentaplegic (dpp), thus affecting segmental identity. Delimits the eye field and prevent inappropriate eye development. Required for proper localization of chordotonal organs within the peripheral nervous system (By similarity). Interacts with Ubx and hth. Nuclear translocation requires interaction with hth. Belongs to the TALE/PBX homeobox family.