Transcriptional repressor of genes that require a bHLH protein for their transcription (PubMed:24618901). May serve as a transcriptional regulator of the Achaete-scute complex (AS-C) genes (PubMed:1528887). Contributes to the neural-epidermal lineage decision during early neurogenesis (PubMed:1427040). Part of the Notch signaling pathway, plays a role in neuroblasts proliferation in embryos and larvae (PubMed:10790334, PubMed:22357926). In the larval brain, together with other self-renewal transcriptional repressors such as klu and dpn, required for type II neuroblast self-renewal and for maintaining erm in an inactive state in intermediate neural progenitors (INP) derived from type II neuroblasts (PubMed:24618901). Homodimer (PubMed:22357926). Heterodimer with dpn (PubMed:22357926). Might form higher-order oligomers (PubMed:22357926). Transcription repression requires formation of a complex with a corepressor protein (Groucho) (By similarity). Expressed in sensory organ precursors in the wing, leg and eye imaginal disk. In embryo, detected in the neuroectoderm at stage 8, and later in neuroblasts at stage 9 (at protein level) (PubMed:22357926). By stage 16, detected only in the neuroblasts (at protein level) (PubMed:22357926). In larvae, detected in a subset of neuroblasts, some of which will give rise to the optic lobe (at protein level) (PubMed:22357926). In embryo, detected during the initial stages of germ band exclusively within the neuroectoderm, both in the territory of the trunk and in cephalic regions (PubMed:1427040). During stage 9, detected within the procephalic lobe and the ventral ectoderm (PubMed:1427040). Has a particular type of basic domain (presence of a helix-interrupting proline) that binds to the N-box (CACNAG), rather than the canonical E-box (CANNTG). 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.