May act as a neurotransmitter or neuromodulator. In larvae, expressed in the CNS and midgut but not in the ring gland, thoracic perisymapthetic organs (tPSO) or abdominal perisymapthetic organs (aPSO) (at protein level). In adults, expressed in brain and thoracic-abdominal ganglion but not in corpora cardiaca and corpora allata (at protein level). Detected in larvae and adults. Belongs to the allatostatin family.