The stage-and cell-specific expression of the Bombyx mori diapause hormone-pheromone biosynthesis activating neuropeptide (BomDH-PBAN) gene in the transformed Drosophila

The diapause hormone (DH) -pheromone biosynthesis activating neuropeptide (PBAN) gene (BomDH-PBAN gene) of the silkworm, Bombyx mori encodes a polyprotein precursor from which DH is released to act on induction of embryonic diapause. We prepared a construct consisting of 7kb of 5' upstream region of the BomDH-PBAN gene fused with the lacZ reporter gene, and successfully introduced it into Drosophila germ line by the P-elementmediated transformation method. Expression of the reporter gene was monitored by enzyme activity and immunoreactivity from embryonic stage to adult stage. At the embryonic stage (stage 11-16), reporter gene expression was found in some cells of the antennomaxillary complex (AMC), the abdominal subepidermal layer at the lateral sides and the posterior spiracles. At the larval stage, some cells in the suboesophageal and the abdominal neuromere in the central nervous system (CNS) became stained clearly. From pupariation to adult eclosion, six ventromedial cells in the abdominal neuromere expressed the reporter gene. Immunocytochemistry using anti-FXPRL-NH2 neuropeptide serum identically traced the same ventromedial cells in the larval abdominal neuromere. Thus, we succeeded in generation of Drosophila melanogaster lines transformed with the BomDH-PBAN gene that should provide an ideal system to analyze the regulation mechanism of the BomDH-PBAN gene expression.