Participates in the control of cell fate choice by uncommitted neuroectodermal cells in the embryo. Transcriptional repressor. Binds DNA on N-box motifs: 5'-CACNAG-3'. Transcription repression requires formation of a complex with a corepressor protein (Groucho). Forms homodimers. In larva, detected in the optic lobe and weakly in the neuroblasts (at protein level) (PubMed:22357926). Expressed at the time when separation of neural and epidermal precursor cells occurs (PubMed:2540957). Mesectodermal expression appears shortly before the onset of gastrulation (PubMed:2540957). In imaginal disks, expression is seen primarily within presumptive proneural clusters of eye-antennal, wing and leg disks (PubMed:2540957). The orange domain and the basic helix-loop-helix motif mediate repression of specific transcriptional activators, such as basic helix-loop-helix protein dimers. The C-terminal WRPW motif is a transcriptional repression domain necessary for the interaction with Groucho, a transcriptional corepressor recruited to specific target DNA by Hairy-related proteins.