RRC ID 3503
Author Futahashi R, Fujiwara H.
Title Regulation of 20-hydroxyecdysone on the larval pigmentation and the expression of melanin synthesis enzymes and yellow gene of the swallowtail butterfly, Papilio xuthus.
Journal Insect Biochem. Mol. Biol.
Abstract The swallowtail butterfly, Papilio xuthus, changes its larval body pattern dramatically during the fourth ecdysis. Cuticular pigmentation occurs with precise timing just before ecdysis. We previously found that the cuticular pigmentation was regulated by three melanin synthesis genes, tyrosine hydroxylase (TH), dopa decarboxylase (DDC), and ebony. We discovered that yellow is strongly expressed in the presumptive black markings earlier than TH and DDC. Because the ecdysis is triggered by 20-hydroxyecdysone (20E), the effects of 20E on the pigmentation and expression of the melanin synthesis genes were examined. Here, we established a method for the topical application of 20E to molting specimens, so that 20E has only a partial effect, resulting in successful ecdysis. When we applied 20E during the mid-phase of the molting period, when the 20E titer is declining, cuticular pigmentation was completely inhibited. The cessation of hormonal treatments caused delayed pigmentation. yellow expression was promoted by a high titer of 20E, whereas the expression of TH, DDC, and ebony was suppressed, suggesting that a decline in the 20E concentration is necessary for the induction of the expression of the latter three genes. These results indicate that cuticular pigmentation is controlled by the exposure to 20E and its removal.
Volume 37(8)
Pages 855-64
Published 2007-8
DOI 10.1016/j.ibmb.2007.02.014
PII S0965-1748(07)00053-7
PMID 17628284
MeSH Animals Butterflies / enzymology Butterflies / growth & development* Butterflies / metabolism Dopa Decarboxylase / metabolism Ecdysteroids / metabolism Ecdysterone / pharmacology* Ecdysterone / physiology Gene Expression Regulation, Developmental / drug effects Insect Proteins / classification Insect Proteins / genetics* Insect Proteins / metabolism Larva / drug effects Larva / enzymology Larva / metabolism Melanins / biosynthesis* Molting / drug effects Phylogeny Pigmentation / drug effects Pigmentation / genetics Tyrosine 3-Monooxygenase / metabolism
IF 3.618
Times Cited 27
Silkworms ?