“Insects Do Not Have Sex Hormones”: A Myth?

Feminizing Wolbachia in an insect, Ostrinia furnacalis (Lepidoptera: Crambidae)

“…The sex in Drosophila is determined at the embryonic stage, and is not affected by diffusing substances such as sex hormones in the later developmental stages. This mechanism is also supported for insects other than Diptera (eg, Hoy, 1994; but see also De Loof and Huybrechts, 1998). In congruence with this widely accepted notion, tetracycline-treated larvae of infected O. furnacalis developed into female adults, suggesting that the feminizing action of Wolbachia operates at the embryonic stage.…”

Sex Steroids in Insects and the Role of the Endosymbiont Wolbachia:A New Perspective

“…De Loof (2006Loof ( , 2008 suggests that ecdysteroids already served as sex hormones long before they acquired a function in moulting. In particular, 20E secreted by the follicle cells of the insect ovary could be the physiological equivalent of vertebrate estrogens, while E -the precursor of the active moulting hormone 20E -should act as a distinct hormone, being the physiological equivalent of the vertebrate testosterone (De Loof & Huybrechts, 1998;De Loof, 2006). Indeed, by using Drosophila larval organ culture Beckstead and colleagues (2007) demonstrate that E can regulate a set of genes that are distinct from those controlled by 20E, thus confirming that it may exert different biological (=hormonal) functions from 20E.…”

TheSf1-related nuclear hormone receptorHr39regulatesDrosophilafemale reproductive tract development and function

“…Many other steroids have been found in Drosophila and other insects, but none has been clearly implicated in sex-specific reproductive functions (reviewed by De Loof et al, 1998). By defining specific biological functions and specific target Cyp genes, it will now be easier to further investigate the mechanism of Hr39 action, and to determine whether it involves the production of new steroid derivatives.…”