Biosynthesis and Inactivation of Ecdysone
Although the fundamental features of the structure and biological function of ecdysone in arthropods have been worked out since its discovery in the early 1930’s, knowledge about metabolism of ecdysone is still rather fragmentary (Horn, 1971). Regarding the biosynthetic pathway of ecdysone, it is known only that ecdysone can be derived from cholesterol or 7-dehydrocholesterol and that α-ecdysone is converted into β-ecdysone. The chemical mechanism for inactivation of ecdysone in vivo is unknown. Also, the site of production of ecdysone in arthropods remains conjectural. Although it has been widely assumed that the ecdysial gland (insect pro-thoracic gland, crustacean Y-organ) manufactures and secretes ecdysone in the manner of a normal endocrine gland, none of the surgical extirpation-replacement experiments done to date with ecdysial glands demonstrate unequivocally that ecdysone is actually produced by this gland (Moriyama et al., 1970).
KeywordsCholesterol Hydrolysis Hydroxyl Pyridinium Dioxane
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