Editing 20-Hydroxyecdysone (section)

==Sources in arthropods==
The primary sources of 20-hydroxyecdysone in larvae are the [[prothoracic gland]], ring gland, gut, and [[fat body|fat bodies]]. These tissues convert dietary [[cholesterol]] into the mature forms of the hormone 20-hydroxyecdysone.<ref>{{cite journal | vauthors = Thummel CS, Chory J | title = Steroid signaling in plants and insects--common themes, different pathways | journal = Genes & Development | volume = 16 | issue = 24 | pages = 3113–29 | date = December 2002 | pmid = 12502734 | doi = 10.1101/gad.1042102 | url = http://www.genesdev.org/cgi/reprint/16/24/3113 | doi-access = free }}</ref> For the most part, these glandular tissues are lost in the adult, with exception of the fat body, which is retained as a sheath of lipid tissue surrounding the brain and organs of the abdomen. In the adult female, the ovary is a substantial source of 20-hydroxyecdysone production.<ref>{{cite journal | vauthors = Handler AM | title = Ecdysteroid titers during pupal and adult development in Drosophila melanogaster | journal = Developmental Biology | volume = 93 | issue = 1 | pages = 73–82 | date = September 1982 | pmid = 6813165 | doi = 10.1016/0012-1606(82)90240-8 }}</ref> Adult males are left with, so far as is currently known, one source of 20-hydroxyecdysone, which is the fat body tissue. These hormone-producing tissues express the [[ecdysone receptor]] throughout development, possibly indicating a functional [[feedback loop| feedback mechanism]].{{cn|date=September 2024}}