...Xiaofeng Zhou; Baohua Zhou; James W. Truman; Lynn M. Riddiford SUMMARY Insect molting is triggered by ecdysteroids, which are produced in the prothoracic glands (PG). The broad ( br ) gene is one of the`early genes' directly regulated by ecdysteroids. Ectopic expression of the BR-Z3 isoform...

...R. D. Watson; T. K. Williams; W. E. Bollenbacher ABSTRACT A recently isolated haemolymph protein appears to be an important regulator of ecdysone biosynthesis by prothoracic glands in Manduca sexta . Using a dose-response titration protocol, the haemolymph titre of this stimulatory factor...

...EJ Eusebio; WJ Moody ABSTRACT The physiological changes which occur during insect moulting are brought about by the steroid hormone 20-hydroxyecdysone ( Riddiford & Truman, 1978 ). The prohormone ecdysone is secreted by the bilaterally paired prothoracic glands (PGs) in response...

.... This delay or inhibition is due to the curtailment of the commitment peak in the ecdysteroid titre, which results from a failure of the prothoracic glands (PG) to increase the synthesis/secretion of the premoulting hormone, ecdysone. Since the PG from ZR512- and JH 1-treated larvae are capable of being...