Pattern reconstruction by dissociated imaginal disk cells of Drosophila melanogaster☆

[摘要] ThecuticularpatternsofwingandlegappendagesofadultDrosophilamelanogasteraredelineated.Thesepatternsconsistofspecificarrangementsofafewtypesofbristles,hairs,andsensilla.Recombinationofdissociatedcellsofimaginaldisks,markedbytwodifferentgenotypes,enablesustoanalyzeinthemetamorphosedstructuresthedeterminationofsinglecellstodifferentiateintoadultcelltypesandtheircapacitytoreconstructadultpatterns.Whilecombinationsofsinglecellsfromcompletewingdisksresultedinchimericreconstructionofadultwingpatterns,cellcombinationsoffragmentsfromdifferentdistrictsofawingdiskleadtoacompletesegregationofthecomponents.Consequently,(a)theisolatedcellsposessadefinitedeterminationforregionalqualities,atleast,and(b)thisdeterminationmanifestsitselfintheseparationofcellswhichbelongtodifferentpatternsorregions.Legpatternsoffirstmale,firstfemale,secondandthirdlegdifferwithrespecttoseveralcharacteristics.Combinationofcellsfromonelegdiskresultsinanautonomousdifferentiationofeachbristletype.Incombinatesofcellsfromdifferentlegdisks,thecharacteristiccelltypesdifferentiateaccordingtotheirorigin.Thus,inmaturelegdisks,themajorcelltypesarealreadydeterminedatthelevelofindividualcells.Inthesecombinatesthereisalsochimericpatternreconstructionbycellscomingfromidenticalpatternsinthedifferentlegpairs.Ontheotherhand,cellscorrespondingtodifferentpatternsineachlegpairappearsegregatedincombinates.Thus,thedeterminedcellpossessessomekindofspatialinformationwhichcharacterizesitasacellinacertainplaceinagivenpattern.Somemechanismsresponsibleforpatternreconstructionarediscussed.

[学科分类] 生物科学（综合）