AS-C proteins are involved in the determination of the neuronal precursors in the peripheral nervous system and the central nervous system. Also involved in sex determination and dosage compensation. Efficient DNA binding requires dimerization with another bHLH protein. Interacts with da (via bHLH motif). Interacts with Bap60. L(1)SC, SC and AC strongly label the presumptive stomatogastric nervous system, while ASE is more prominent in the presumptive procephalic lobe. Associates with the somatic nuclei through nuclear cycles 9 and 10. During nuclear cycle 11 distributes uniformly in the embryo. Expressed zygotically in embryos from 0 to 12 hours after fertilization, with a peak of expression during the 2 to 4 hour period. Expression reappears in third instar larvae and pupae.