The role of ecdysteroid in the regulation of ovarian growth and oocyte maturation in Rhodnius prolixus, a vector of Chagas disease

Recently Dr. Samiha Benrabaa, Postdoctoral Fellow, from Lange & Orchard Lab had her study on The role of ecdysteroid in the regulation of ovarian growth and oocyte maturation in Rhodnius prolixus, a vector of Chagas disease published by the Journal of Experimental Biology

https://doi.org/10.1242/jeb.244830

Ecdysteroid is the main insect steroid hormone that has essential roles in development, molting, and metamorphosis. The primary source of ecdysteroids in the larval stages of insects is the prothoracic gland (PG), and in adult females, the ovary. In this study, we investigated the role of ecdysteroid in reproduction in females of the medically-important kissing bug, Rhodnius prolixus. Ecdysteroid or 20-hydroxyecdysone (20E), is synthesized via enzymes in the ecdysteroidogenic pathway that are encoded by Halloween genes. We have identified and characterized the Halloween genes, and the ecdysone receptor in the R. prolixus ovary. We examined the role of 20E in R. prolixus reproduction using RNA interference. We found that interfering with the ecdysteroid signaling pathway reduced the number of eggs produced, the eggs laid, and their hatching rate. Knockdown of the 20E receptor also altered the expression of the chorion gene transcripts which led to abnormal egg shapes. Considering these findings, it may be possible to identify RNA-interference targets for pest management thereby controlling insect populations and their diseases.