title: Alterations in ecdysone content during the post-embryonic development of Chironomus thummi: correlations with chromosomal puffing.
abstract: The ecdysone titer of larvae and pupae of Chironomus thummi was determined by radioimmune assay (RIA) and revealed a concentration of about 150 ng/g fresh weigth in late third instar larvae and a peak of more than 450 ng/g fresh weight just preceding pupation. The ecdysone titer curve shows a high degree of correlation with previously observed puffing activity at the ecdysone sensitive chromosomal site IIIdl. Further, beta-ecdysone is the only endogenous ecdysone detected by high pressure liquid chromatography during larval-pupal development. It was also observed that developmentally arrested Chironomus contain less ecdysone than "normal" larvae.
mesh_terms: D000818:Animals; D002875:Chromosomes / Q000648:ultrastructure*; D004175:Diptera / Q000235:genetics / Q000254:growth & development*; D004440:Ecdysone / Q000378:metabolism*; D007814:Larva / Q000378:metabolism; D011679:Pupa / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D004440:Ecdysone