Probable transcription factor required for peripheral nervous system morphogenesis, eye development and oogenesis. May be required for the transmission of the dpp signal and for a morphogenetic movement of the medulla in the brain that reorients the second optic lobe relative to the first. Plays a role in determining proper dorsal cell fates leading to the formation of the dorsal appendages. Belongs to the TSC-22/Dip/Bun family. Extended N-terminus.