MultitoxinBt-cropsexpressinginsecticidaltoxinswithdifferentmodesofaction,forexample,CryandVip,areexpectedtoimproveresistancemanagementintargetpests.WhileCry1Aresistancehasbeenrelativelywellcharacterizedinsomeinsectspecies,thisisnotthecaseforVip3A,forwhichnomechanismofresistancehasyetbeenidentified.HereweappliedHT-SuperSAGEtoanalyzethetranscriptomeoftheguttissueoftobaccobudwormHeliothisvirescens(F.)laboratory-selectedforVip3Aaresistance.Fromatotalof1324252sequencereads,5895126-bptagswereobtainedrepresenting17751nonsingletonuniquetranscripts(UniTags)fromgeneticallysimilarVip3Aa-resistant(Vip-Sel)andsusceptiblecontrol(Vip-Unsel)strains.Differentialexpressionwassignificant(≥2.5foldor≤0.4;P<0.05)for1989sequences(11.2%oftotalUniTags),where420representedoverexpressed(OE)and1569underexpressed(UE)genesinVip-Sel.BLASTNsearchesmapped419UniTagstoH.virescenssequencecontigs,ofwhich,416(106OEand310UE)wereunambiguouslyannotatedtoproteinsinNCBInonredundantproteindatabases.GeneOntologydistributed345ofannotatedUniTagsin14functionalcategorieswithmetabolism(includingserine-typehydrolases)andtranslation/ribosomebiogenesisbeingthemostprevalent.AUniTaghomologoustoaparticularmemberoftheREsponsetoPAThogen(REPAT)familywasfoundamongmostoverexpressed,whileUniTagsrelatedtotheputativeVip3Aa-bindingribosomalproteinS2(RpS2)wereunderexpressed.qRT-PCRofasubsetofUniTagsvalidatedtheHT-SuperSAGEdata.ThisstudyisthefirstprovidinglepidopteranguttranscriptomeassociatedwithVip3Aaresistanceandafoundationforfutureattemptstoelucidatetheresistancemechanism.
