Editing 20-Hydroxyecdysone (section)

===Use as research tool===
20-Hydroxyecdysone and other ecdysteroids are used in biochemistry research as [[inducer]]s in transgenic animals, whereby a new gene is introduced into an animal so that its expression is under the control of an introduced [[ecdysone receptor]].  Adding or removing ecdysteroids from the animal's diet then gives a convenient way to turn the inserted gene on or off. At usual doses, 20-hydroxyecdysone appears to have little or no effect on animals that do not have extra genes inserted. Given its high oral [[bioavailability]], therefore, it is useful for determining whether the [[transgene]] has been taken up effectively.<ref>{{cite journal | vauthors = Saez E, Nelson MC, Eshelman B, Banayo E, Koder A, Cho GJ, Evans RM | title = Identification of ligands and coligands for the ecdysone-regulated gene switch | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 97 | issue = 26 | pages = 14512–7 | date = December 2000 | pmid = 11114195 | pmc = 18950 | doi = 10.1073/pnas.260499497 | url = http://www.pnas.org/cgi/reprint/97/26/14512.pdf | bibcode = 2000PNAS...9714512S | doi-access = free }}</ref> However, studies mentioned below show that 20E is not totally inert in non-transgenic mammals.