English

Noun

1. A hormone in insects and other arthropods that promotes molting.

Related terms

• ecdysis

Ecdysone is a steroidal prohormone of the major insect moulting hormone 20-hydroxyecdysone, which is secreted from the prothoracic glands. Insect moulting hormones (ecdysone and its homologues) are generally called ecdysteroids. Ecdysteroids act as moulting hormones of arthropods but also occur in other related phylums where they can play different role. In Drosophila melanogaster ecdysone concentration increase induces the expression of genes coding for proteins that the larva requires, and it cause chromosome puffs (sites of high expression) to form. Ecdysteroids also appear in many plants mostly as a protection agents (toxins or antifeedants) against herbivorous insects. These phytoecdysteroids have medicinal value and are part of herbal adaptogenic remedies like Cordyceps. A pesticide sold with the name MIMIC has ecdysteroid activity, although its chemical structure has little resemblance to the ecdysteroids.

See also

• Ecdysone receptor

External links

• Ecdybase, The Ecdysone Handbook - a free online ecdysteroids database