Ecdysone is a

prohormone A prohormone is a committed precursor of a hormone consisting of peptide hormones synthesized together that has a minimal hormonal effect by itself because of its expression-suppressing structure, often created by protein folding and binding additi ...

of the major insect molting hormone

20-hydroxyecdysone 20-Hydroxyecdysone (ecdysterone or 20E) is a naturally occurring ecdysteroid hormone which controls the ecdysis (moulting) and metamorphosis of arthropods. It is therefore one of the most common moulting hormones in insects, crabs, etc. It is als ...

, which is secreted from the

prothoracic gland The prothoracic glands are either of a pair of endocrine glands located in the prothorax of certain insects that regulate molting. They have an ectodermal origin and secrete ecdysteroids, such as ecdysone and 20-hydroxyecdysone 20-Hydroxyecdyson ...

s. It is of steroidal structure. Insect molting hormones (ecdysone and its homologues) are generally called

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 ...

s. Ecdysteroids act as moulting hormones of

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chiti ...

s but also occur in other related phyla where they can play different roles. In ''

Drosophila melanogaster ''Drosophila melanogaster'' is a species of fly (the taxonomic order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the " vinegar fly" or "pomace fly". Starting with ...

'', an increase in ecdysone concentration induces the expression of genes coding for proteins that the larva requires, and it causes chromosome puffs (sites of high expression) to form in polytene chromosomes. Recent findings in the laboratory of Chris Q. Doe have found a novel role of this

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are require ...

in regulating temporal gene transitions within

neural stem cells Neural stem cells (NSCs) are self-renewing, multipotent cells that firstly generate the radial glial progenitor cells that generate the neurons and glia of the nervous system of all animals during embryonic development. Some neural progenitor ste ...

of the fruit fly. Ecdysone and other ecdysteroids also appear in many plants mostly as a protection agent ( toxins or

antifeedant Antifeedants are organic compounds produced by plants to inhibit attack by insects and grazing animals. These chemical compounds are typically classified as secondary metabolites in that they are not essential for the metabolism of the plant, but i ...

s) against

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpar ...

insects. These

phytoecdysteroid Phytoecdysteroids are plant-derived ecdysteroids. Phytoecdysteroids are a class of chemicals that plants synthesize for defense against phytophagous (plant eating) insects. These compounds are mimics of hormones used by arthropods in the molting pr ...

s have been reputed to have

medicinal Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practic ...

value and are part of herbal

adaptogen Adaptogens or adaptogenic substances are used in herbal medicine for the claimed stabilization of physiological processes and promotion of homeostasis. History The concept of adaptogens was originally created in 1947 to describe a substance that ...

ic remedies like Cordyceps, yet an ecdysteroid precursor in plants has been shown to have cytotoxic properties as well as antioxidant properties on lipid peroxidation.

Tebufenozide Tebufenozide is an insecticide that acts as a molting hormone. It is an agonist of the ecdysone receptor that causes premature molting in larvae. It is primarily used against caterpillar pests. Because it has high selectivity for the targeted ...

, sold under the Bayer trademark MIMIC,apvma.gov.au: "Tebufenozide in the product Mimic 700 WP Insecticide, Mimic 240 SC Insecticide"
/ref> has ecdysteroid activity although its chemical structure has little resemblance to the ecdysteroids.

External links

Ecdybase
The Ecdysone Handbook - a free online ecdysteroids database

Notes

Steroids Insect hormones Insect developmental biology {{insect-stub

See also

External links

Notes