Ecdysone
Encyclopedia
Ecdysone is a steroid
al prohormone
of the major insect molting
hormone 20-hydroxyecdysone
, which is secreted from the prothoracic gland
s. Insect molting hormones (ecdysone and its homologues) are generally called ecdysteroid
s. Ecdysteroids act as moulting hormones of arthropod
s but also occur in other related phyla
where they can play different roles. In Drosophila melanogaster
, 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. Ecdysteroids also appear in many plants mostly as a protection agent (toxins or antifeedants) against herbivorous insects. These phytoecdysteroid
s have been reputed to have medicinal value and are part of herbal adaptogen
ic remedies like Cordyceps
, yet an ecdyseroid precursor in plants has been shown to have cytotoxic properties . A pesticide sold with the name MIMIC has ecdysteroid activity, although its chemical structure has little resemblance to the ecdysteroids.
Steroid
A steroid is a type of organic compound that contains a characteristic arrangement of four cycloalkane rings that are joined to each other. Examples of steroids include the dietary fat cholesterol, the sex hormones estradiol and testosterone, and the anti-inflammatory drug dexamethasone.The core...
al prohormone
Prohormone
A prohormone is a substance that is a precursor to a hormone, usually having minimal hormonal effect by itself. The term has been used in medical science since the middle of the 20th century. The primary function of a prohormone is to enhance the strength of the hormone that already occurs in the...
of the major insect molting
Ecdysis
Ecdysis is the moulting of the cuticula in many invertebrates. This process of moulting is the defining feature of the clade Ecdysozoa, comprising the arthropods, nematodes, velvet worms, horsehair worms, rotifers, tardigrades and Cephalorhyncha...
hormone 20-hydroxyecdysone
20-hydroxyecdysone
20-Hydroxyecdysone is a naturally occurring ecdysteroid hormone which controls the ecdysis and metamorphosis of arthropods. It is therefore one of the most common moulting hormones in insects, crabs, etc...
, which is secreted from the prothoracic gland
Prothoracic gland
The prothoracic glands are either of a pair of endocrine glands located in the prothorax of certain insects and regulating molting. They have a ectodermal origin and secrete ecdysteroids, such as ecdysone and 20-hydroxyecdysone....
s. Insect molting hormones (ecdysone and its homologues) are generally called ecdysteroid
Ecdysteroid
Ecdysteroids are insect moulting and sex hormones which include ecdysone and its homologues such as 20-hydroxyecdysone. Ecdysteroids also occur in other invertebrates where they can play a different role. They also appear in many plants mostly as a protection agents against herbivore insects...
s. Ecdysteroids act as moulting hormones of arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s but also occur in other related phyla
Phyla
Phyla, the plural of phylum, may refer to:* Phylum, a biological taxon between Kingdom and Class* Phylum , in linguistics, a large division of possibly related languagesPhyla, as a singular, may refer to:...
where they can play different roles. In Drosophila melanogaster
Drosophila melanogaster
Drosophila melanogaster is a species of Diptera, or the order of flies, in the family Drosophilidae. The species is known generally as the common fruit fly or vinegar fly. Starting from Charles W...
, 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. Ecdysteroids also appear in many plants mostly as a protection agent (toxins or antifeedants) against herbivorous insects. These phytoecdysteroid
Phytoecdysteroid
Phytoecdysteroids are plant derived ecdysteroids. Phytoecdysteroids are a class of chemicals that plants synthesize for defense against phytophagous insects. These compounds are exact replicas of hormones used by the arthropod and crustacean families in the molting process known as ecdysis...
s have been reputed to have medicinal value and are part of herbal adaptogen
Adaptogen
An adaptogen is a herbal product claimed to increase resistance to stress, trauma, anxiety and fatigue. The term is used mainly by herbalists who also refer to adaptogens as rejuvenating herbs, qi tonics, rasayanas, or restoratives...
ic remedies like Cordyceps
Cordyceps
Cordyceps is a genus of ascomycete fungi that includes about 400 described species. All Cordyceps species are endoparasitoids, mainly on insects and other arthropods ; a few are parasitic on other fungi. The best known species of the genus is Cordyceps sinensis, first recorded as yartsa gunbu in...
, yet an ecdyseroid precursor in plants has been shown to have cytotoxic properties . A pesticide sold with the name MIMIC has ecdysteroid activity, although its chemical structure has little resemblance to the ecdysteroids.
External links
- Ecdybase, The Ecdysone Handbook - a free online ecdysteroids database