ETS transcription factor with a prominent role during development of the eye and the nervous system (PubMed:8223245, PubMed:8033205, PubMed:23757412, PubMed:28245922). Required for glial-neuronal cell interactions at the ventral midline which are necessary for the proper elaboration of commissures in the embryonic CNS (PubMed:8223245). Required for normal EGFR-induced photoreceptor development probably as a downstream effector of Ras85D (PubMed:8033205, PubMed:23757412). In larval eye imaginal disks, activated by MAPK phosphorylation following EGFR activation, induces transcription of isoform P1 which in turn activates transcription of target genes essential for photoreceptor development (PubMed:23757412). Required for normal EGFR-induced photoreceptor development (PubMed:23757412). Following transcriptional activation by isoform P2, acts as a constitutive activator of transcription, leading to induction of target genes essential for photoreceptor development (PubMed:8033205, PubMed:23757412). In larval brains, involved in the maintenance of type II neuroblast self-renewal and identity together with brat, btd and pros; prevents intermediate neuronal progenitor (INP) dedifferentiation by regulating the expression of erm probably via Notch signaling; suppresses Ase expression in type II neuroblasts and promotes the generation of intermediate neuronal progenitors (PubMed:22143802, PubMed:27151950, PubMed:27510969, PubMed:28899667, PubMed:28245922). Expressed in type II neuroblasts in larval brain (at protein level) (PubMed:27151950, PubMed:28245922). Expressed in a complex dynamic pattern in early embryos, including the midline and midline glial cells (PubMed:8223245, PubMed:1577186, PubMed:2834248). Expressed throughout development with lower levels during larval development (PubMed:1577186). Expressed in the eye imaginal disk in and posterior to the morphogenetic furrow (PubMed:8033205). Isoform P2: Detected in the precellular blastoderm stage localized at the anterior tip of the embryo (PubMed:8223245). Detected during gastrulation in the mesoderm (PubMed:8223245, PubMed:23757412). As the germband retracts (stage 12) detected in a few cells located at the dorsal roof at the midline of the CNS (PubMed:8223245). These cells correspond to the midline glial cells, in which expression continues until the end of embryogenesis (PubMed:8223245). Major isoform expressed in the eye imaginal disk in and posterior to the morphogenetic furrow (PubMed:8033205). Isoform P1: Expressed within the differentiated region of the disk including and posterior to the morphogenetic furrow in the proneural photoreceptor clusters (at protein level) (PubMed:23757412). Detected during the cellular blastoderm stage in two broad stripes in the lateral neurogenic region (PubMed:8223245). At the beginning of gastrulation detected in the dorsal edge of the neurogenic region (PubMed:8223245). During segmentation (stage 11), detected in the ventral ectoderm and in a group of cells surrounding the future tracheal pits, in the head region and the lateral body wall (PubMed:8223245). In the CNS, detected during germband retraction, in the glial cells and in the midline (PubMed:8223245). In larval brains, major neuroblast-specific isoform (PubMed:22143802). Phosphorylated at Thr-151 by rl. Embryonic lethal showing loss of photoreceptors (PubMed:8033205, PubMed:8223245, PubMed:23757412). In larvae, RNAi-mediated knockdown results in a transformation of type II neuroblasts into type I neuroblasts, elimination of intermediary neuronal progenitors (INP) and generation of extra type II neuroblasts; in the ventral nerve cord, results in increased numbers of type I neuroblasts (PubMed:27510969, PubMed:28899667, PubMed:27151950). Simultaneous RNAi-mediated knockdown of the zinc-finger transcriptional repressor erm, the transcriptional repressor E(spl)mdelta-HLH or the transcriptional repressor dpn restore normal neuroblast numbers (PubMed:28899667). Simultaneous RNAi-mediated knockdown of N partially restores normal neuroblast numbers and inhibits ectopic erm expression in the central brain and ventral nerve cord (PubMed:27151950). Belongs to the ETS family. Aberrant splicing.