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. Expressed at the time when separation of neural and epidermal precursors cells occurs. Mesectodermal expression appears shortly before the onset of gastrulation. 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.