Ecdysone is a prohormone of the major insect molting hormone 20-hydroxyecdysone, secreted from the prothoracic glands. It is of

steroid A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes t ...

al structure. Insect molting hormones (ecdysone and its homologues) are generally called

ecdysteroid Ecdysteroids are arthropod steroid hormones that are mainly responsible for molting (ecdysis), development and, to a lesser extent, reproduction; examples of ecdysteroids include ecdysone, 20-hydroxyecdysone (ecdysterone), turkesterone and 2- ...

s. Ecdysteroids act as moulting hormones of

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

s but also occur in other related

phyla Phyla, the plural of ''phylum'', may refer to: * Phylum, a biological taxon between Kingdom and Class * by analogy, in linguistics, a large division of possibly related languages, or a major language family which is not subordinate to another Phy ...

where they can play different roles. In ''

Drosophila melanogaster ''Drosophila melanogaster'' is a species of fly (an insect of the Order (biology), 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", "pomace fly" ...

'', an increase in ecdysone concentration induces the expression of genes coding for proteins that the larva requires. 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 Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physio ...

in regulating temporal gene transitions within neural stem cells of the fruit fly. Ecdysone and other ecdysteroids also appear in many plants mostly as a protection agent (

toxins A toxin is a naturally occurring poison produced by metabolic activities of living cells or organisms. They occur especially as proteins, often conjugated. The term was first used by organic chemist Ludwig Brieger (1849–1919), derived ...

antifeedant Antifeedants are organic compounds produced by plants to repel herbivores through distaste or toxicity. These chemical compounds are typically classified as secondary metabolites in that they are not essential for the metabolism of the plant, but ...

s) against

herbivorous A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat n ...

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 molt ...

s have been reputed to have

medicinal Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

value. They are part of herbal

adaptogen Adaptogens, or adaptogenic substances, are used in herbal medicine for the purported stabilization of physiological processes and promotion of homeostasis. The concept of adaptogens is not accepted in mainstream science and is not approved as a ...

ic remedies like Cordyceps, yet an ecdysteroid precursor in plants has been shown to have

cytotoxic Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are toxic metals, toxic chemicals, microbe neurotoxins, radiation particles and even specific neurotransmitters when the system is out of balance. Also some types of dr ...

properties as well as

antioxidant Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants ...

properties on lipid peroxidation. Tebufenozide, sold under the

Bayer Bayer AG (English: , commonly pronounced ; ) is a German multinational pharmaceutical and biotechnology company and is one of the largest pharmaceutical companies and biomedical companies in the world. Headquartered in Leverkusen, Bayer' ...

trademark MIMIC, has ecdysteroid activity although its chemical structure has little resemblance to the ecdysteroids.{{Cite book , doi = 10.1021/bk-2000-0767.ch002 , chapter = Tebufenozide: A Novel Caterpillar Control Agent with Unusually High Target Selectivity , title = Green Chemical Syntheses and Processes , series = ACS Symposium Series , date = 2000 , last1 = Carlson , first1 = Glenn R. , volume = 767 , pages = 8–17 , isbn = 978-0-8412-3678-3

References

External links

Ecdybase
The Ecdysone Handbook - a free online ecdysteroids database Steroids Insect hormones Insect developmental biology

See also

References

External links