Ecdysteroid

Ecdysteroids are arthropod steroid hormones that are mainly responsible for molting, development and, to a lesser extent, reproduction; examples of ecdysteroids include ecdysone, ecdysterone, turkesterone and 2-deoxyecdysone. These compounds are synthesized in arthropods from dietary cholesterol upon metabolism by the Halloween family of cytochrome P450s. Phytoecdysteroids also appear in many plants mostly as a protection agents (toxins or antifeedants) against herbivore insects.