Notch pathway component, may contribute to the specificity between lateral and inductive Notch signaling pathways in the wing disk. Required during many developmental stages including oogenesis, embryogenesis and imaginal development of the eye, wing and leg. Ebi and sno regulate EGFR-dependent Delta transcription in the developing eye, by antagonizing a repressor function of Suppressor of Hairless (Su(H)). They are required in the R-cells for normal cone cell development. Interacts with vg for function in the wing disk. Interacts with Su(H) for function in the eye disk. At stage 8, when the formation of the midline precursor cells depends on Notch signaling, high level of expression is seen in the midline precursor cells and a lower level in the surrounding epidermal cells. Between stages 11 and 14, expression is uniform throughout the epidermis, and at stage 16, high level of expression is restricted to the central nervous system. Expressed in the larval leg, wing and eye imaginal disks. Expression is over the wing disk and accumulates within the pleural region. Expressed both maternally and zygotically. First detected at the syncytial blastoderm stage. Loss of wingless, vestigial, cut, and E(spl)-m8 expression at the dorsal/ventral (D/V) boundary of the wing disk causing improper boundary specification. This causes defective wing pouch development and consequent thickening of wing veins. Belongs to the SBNO family. Intron retention. Truncated N-terminus.