Developmental studies of lethality associated with the Antennapedia gene complex in Drosophila melanogaster☆

[摘要] Anumberofdominanthomoeoticmutationsarelocalizedtotheproximalrightarmofchromosome3ofDrosophilamelanogasterandarethoughttorepresentmembersofagenecomplexthatcontrolsnormaldeterminativedecisionsintheheadandthorax.WehavedesignatedthiscomplextheAntennapediagenecomplex(ANT-C).DevelopmentalstudiesweredonetoinvestigatethenatureofthelethalityassociatedwithmembersoftwoofthecomplementationgroupswithinANT-C.Thefirstcomplementationgroup,representedbythemutantMultipleSexCombs(Msc)ischaracterizedbyembryoniclethalitywhenheterozygouswithadeletionoftheANT-C.ThesecondcomplementationgroupconsistsofAntennapedia(Antp),Antennapedia-ExtraSexCombs(AntpScx),andthelethalsrecoveredasrevertantsofAntpNs.WhenheterozygousforadeletionoftheANT-Corinheterozygousconditionwitheachother,themembersofthisgroupshoweffectivelethalphasesspanningfromembryo-larvalboundarytolatelarvalstages.WakimotoandKaufman(1981)showthattheAntp+geneactstoestablishnormaldeterminativestatesinthethorax.Inthepresentwork,transplantationofeye-antennaldisksfromlethalindividualsheterozygousfortwodifferentAntpNsrevertantchromosomesintowild-typehostsallowedtheassessmentofthefunctionoftheAntp+alleleintheantenna.Sincethesetransplantsformedonlyantennalstructuresandshowednoevidenceoftheantennal→legtransformationseeninAntpNscontrols,weconcludethatthewild-typefunctionoftheAntplocusisnotnecessaryfortheestablishmentand/ormaintenanceoftheantennaldeterminedstate.WesuggestthatregulatorymechanismsassociatedwiththeAntp+structuralgenenormallyfunctionbothtoallowitsexpressioninthethoraxandtorepressitintheantenna.

[学科分类] 生物科学（综合）