Title

「Functional identification of a potent inhibitor of insect steroid hormone biosynthesis」 ポスター🔗

Lecturer

Dr. Eisuke Imura

Date & Time

14:00~15:00, AUGUST 22nd (Thu.), 2024

Venue

Seminar Room C/D, Building G, Faculty of Medicine Campus

Abstract

Steroid hormones play key roles in many aspects of animal physiology. In insects, the principal steroid hormones called ecdysteroids coordinate growth and maturation by controlling molting and metamorphosis. Ecdysteroids are also involved in a variety of physiological processes during adulthood, such as immunity, longevity, and reproduction. Ecdysteroid signaling can therefore be a potential target for controlling various aspects of insect physiology. In this study, in vivo chemical screening was conducted to identify small compounds that inhibit ecdysteroid signaling in Drosophila. Feeding one compound at nanomolar concentrations inhibited pupariation, resulting in prolongation of the larval period and a consequent increase in body size. The ecdysteroid titer in the compound-fed larvae was significantly reduced, and the pupariation defect was rescued by concurrent feeding of an active ecdysteroid, 20-hydroxyecdysone. Feeding of the compound significantly reduced the cell size of the ecdysteroidogenic tissue, the prothoracic gland (PG), without changing their cell numbers. During the larval period, the PG increases its cell size through endoreplication. Forced induction of endoreplication in PG cells rescued the effect of the compound. These results suggest that the compound disrupts Drosophila development by blocking endoreplication in the PG and thereby suppressing ecdysteroid biosynthesis. Further characterization of the mode-of-action of this novel steroidogenesis inhibitor is currently underway.

Contact

Laboratory of Cell Recognition and Pattern Formation、CeLiSIS
Tadashi Uemura 075-753-9238