Cellular metamorphosis: III. Timing of adult determination within the larval development of the labial gland duct in the tobacco hornworm☆
[摘要] Thesphingidmoth,Manducasexta,typicallypassesthroughfivelarvalinstars,apupal,andanadultstage.Thelarvallabialglandssecretesilkinthefirstinstarandaviscouslubricantinthefifth.Duringmetamorphosistheglandsdevelopintosalivaryorganswhichproduceaninvertase-richsecretion.Innormaldevelopment,theuniformpopulationofcellsintheductofthelarvalglandtransformsintothefoursequentiallyarrangedregionsofsecretoryandconductivecellsoftheadultgland.Inordertodeterminewhencompetencetoformtheadultglandisestablished,fragmentsoflabialglandductsfromfirstthroughfifthinstarlarvaewereimplantedintopupae.Theseglandfragmentsunderwentmetamorphosiswiththeirhosts,passingthroughthesamedevelopmentalphases.Glandsfromasearlyasthefirstinstarwerecompetenttoformhistologicallyandfunctionallynormaladultregions.Inlaterinstars,transplantsofmeasuredfragmentsdemonstratedthatlarvalcellswereprogrammedinsitutodevelopintothefouradultcelltypes.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
