The Venus reporter driven by the 5.7 kb
npr22 promoter was expressed in many cells mainly in the head region; the
npr-22prom::Venus expression was observed in head muscles, the I2 neurons, the MC neurons, the RIH neuron, the AIA neurons, the AUA neurons, the ASK neurons (strong in larval worms), the ASI neurons (strong in larval worms), a few B-type motorneurons in the posterior ventral nerve cord (variable), pharyngeal muscles, body wall muscles (weak), the intestine (weak), and a few classes of unidentified cells anterior to the nerve ring. In the I2, MC, RIH, AIA, AUA, and posterior B-type motorneurons, we confirmed the co-expression of established cell markers.