Control of vitellogenin synthesis in the Monarch butterfly by juvenile hormone☆

[摘要] YolkformationintheMonarchbutterfly,asinmanyotherinsects,entailsjuvenilehormone-inducedsynthesisinthefatbody,transportinthehemolymph,anduptakeintotheoocytesofspecificsex-limitedprotein,thevitellogenin.IntheMonarch,vitellogeninfirstappearsinthehemolymph1dayafteremergenceoftheadultbutterflyandthenrisesrapidlyinconcentrationforatleast3days.Thesynthesisofvitellogenininadultfemaleswasshownbytheincorporationof[3H]leucine.Activelabelingwasobservedatthesametimeasthepresenceofvitellogenininthehemolymphwasfirstdetectable,andtheradioactivityinvitellogeninexpressedasapercentageofradioactivityintotalbloodproteinsreached50–60%3daysafteradultemergence.Theappearanceofvitellogeninwaspreventedbyligatureoffreshlyemergedbutterfliesattheneckandrestoredbyinjectionofjuvenilehormone.Alowyetsignificantstimulationofvitellogeninsynthesiscouldbedetectedasearlyas10hrafteradministrationofthehormoneintoneck-ligatedbutterflies,andafter30to50hrabout40%ofthetotalbloodproteinlabelwasfoundinthespecificprotein.WithC18-juvenilehormone(JH-I),0.1μgperanimalwaseffectiveininducingalowlevelofvitellogeninsynthesis,andbetween0.01and1μg,alinearrelationshipbetweensynthesisandlogdosewasobserved.ThesyntheticanalogZR-512wasalsoactive.Inapreliminaryexperiment,actinomycinDeffectivelyblockedtheinductionofvitellogeninsynthesis.

[学科分类] 生物科学（综合）