Nemo phosphorylates Even-skipped and promotes Eve-mediated repression of odd-skipped in even parasegments during Drosophila embryogenesis

摘要

Drosophilaemnemo/em(emnmo/em)andotherNemo-likekinasefamilymembers(Nlks)arewell-establishedkeyregulatorsofnumerousconservedsignalingpathways,suchasWgandBMP.emnmo/emmutantsdisplaypleiotropicdefectsatdifferentdevelopmentalstages,includingtheembryo.Inthisstudywedescribeadetailedcharacterizationofembryoniccuticlepatterningdefectsassociatedwithmaternallossofemnmo/em.emnmo/emmutantembryosconsistentlyshowsegmentationdefects,mostfrequentlyfusionsofpairsofdenticlebeltsinalternatingsegments.Thesephenotypesarereminiscentofthoseassociatedwithdefectsinpair-rulepatterning.GeneticinteractionstudiesdemonstratethatNmopromotesEven-skipped(Eve)activityandisrequiredtopromotetheexpressionoftheEvetarget,emengrailed/em(emen/em),inevennumberedparasegments.WefindthatNmoregulatesasubsetofEveactivitiesbystimulatingEve-mediatedsuppressionoftheemodd-skipped/em(emodd/em)repressor.Furthermore,weisolateNmoinaproteincomplexwithEveandshowthatNmophosphorylatesEveineminvitro/emkinaseassays.ThesestudiesrevealanovelrolefortheNmokinaseinembryonicpatternformationthroughitsregulationofthehomeodomain-containingtranscriptionfactorEve./p/div