MicroRNA Profile of Marek’s Disease Virus-Transformed T-Cell Line
- 格式:pdf
- 大小:404.30 KB
- 文档页数:9
JOURNALOFVIROLOGY,Apr.2008,p.4007–4015Vol.82,No.8
0022-538X/08/$08.00ϩ0doi:10.1128/JVI.02659-07
Copyright©2008,AmericanSocietyforMicrobiology.AllRightsReserved.
MicroRNAProfileofMarek’sDiseaseVirus-TransformedT-CellLine
MSB-1:PredominanceofVirus-EncodedMicroRNAsᰔ
YongxiuYao,1YuguangZhao,1HongtaoXu,1LorraineP.Smith,1CharlesH.Lawrie,2
MichaelWatson,1andVenugopalNair1*
DivisionofMicrobiology,InstituteforAnimalHealth,Compton,BerkshireRG207NN,UnitedKingdom,1and
LRFMolecularHaematologyUnit,NuffieldDepartmentofClinicalLaboratorySciences,Universityof
Oxford,OxfordOX39DU,UnitedKingdom2
Received14December2007/Accepted25January2008
ResearchoverthelastfewyearshasdemonstratedtheincreasingroleofmicroRNAs(miRNAs)asmajor
regulatorsofgeneexpressionindiversecellularprocessesanddiseases.Severalviruses,particularlyherpes-
viruses,alsousethemiRNApathwayofgeneregulationbyencodingtheirownmiRNAs.Marek’sdisease(MD)
isawidespreadlymphomatousneoplasticdiseaseofpoultrycausedbythehighlycontagiousMarek’sdisease
virustype1(MDV-1).Recentstudiesusingvirus-infectedchickenembryofibroblastshaveidentifiedatleast
eightmiRNAsthatmaptotheRL/RSregionoftheMDVgenome.SinceMDVisalymphotropicvirusthat
inducesT-celllymphomas,analysisofthemiRNAprofileinT-celllymphomawouldbemorerelevantfor
examiningtheirroleinoncogenesis.WedeterminedtheviralandhostmiRNAsexpressedinMSB-1,a
lymphoblastoidcelllineestablishedfromanMDV-inducedlymphomaofthespleen.Inthispaper,wereport
theidentificationof13MDV-1-encodedmiRNAs(12bydirectcloningand1byNorthernblotting)fromMSB-1
cells.ThesemiRNAs,fiveofwhicharenovelMDV-1miRNAs,maptotheMeqandlatency-associated
transcriptregionsoftheMDVgenome.Furthermore,weshowthatmiRNAsencodedbyMDV-1andthe
coinfectedMDV-2accountedfor>60%ofthe5,099sequencesoftheMSB-1“miRNAome.”Severalchicken
miRNAs,someofwhichareknowntobeassociatedwithcancer,werealsoclonedfromMSB-1cells.Highlevels
ofexpressionofMDV-1-encodedmiRNAsandpotentiallyoncogenichostmiRNAssuggestthatmiRNAsmay
havemajorrolesinMDVpathogenesisandneoplastictransformation.
Marek’sdisease(MD)isanaturallyoccurringrapid-onset
aggressiveT-celllymphomaofpoultry.NamedaftertheHun-
garianveterinarianJos´zefMarek,whofirstreportedthedis-
easein1907(41),thediseaseisinducedbyMarek’sdisease
virustype1(MDV-1),ahighlycontagiousalphaherpesvirus
belongingtothegenusMardivirusofthefamilyHerpesviridae
(31).Apartfrombeingamajordiseaseaffectingpoultryhealth
andwelfare,MDisconsideredtobeanexcellentbiomedical
modelforvirus-inducedlymphoma(7,14).Amongthe100-
plusgenespredictedfortheMDVgenome(40,47,48),the
geneforthebasicleucinezipperproteinMeqisconsideredto
bethemajoroncogene(39,44).SomeofthefunctionsofMeq
associatedwithoncogenicproperties,suchasitsinteraction
withCtBP,parallelthoseofotherviraloncogenicsequences,
suchasadenovirusE1AandEpstein-Barrvirus(EBV)nuclear
antigensEBNA3Aand-3C(6),highlightingtheconvergent
evolutionofoncogenicpathwaysintheseviruses.Recentstud-
ieshavealsoidentifiedtheroleofothergenes,suchasthepp38
(23),viralinterleukin-8(vIL-8)(49),ICP4(15,38),R-LORF4
(33),UL36(32),andMDV-encodedtelomeraseRNA(22,63)
genes,inpathogenesis.
Increasingevidencedemonstratesthatinadditiontothe
directroleofprotein-encodinggenes,noncodingRNAshave
profoundeffectsinmediatingneoplastictransformation(13).Amongthese,the22-nucleotidemicroRNAs(miRNAs)have
emergedasamajorregulatorytierofgeneexpression,withthe
potentialoftargetingupto30%ofgenesinhumans(17,27,
37).Giventheirsmallsizewiththecapabilityforregulating
multiplegenes,severalviruseshaveadoptedthemiRNAma-
chinerytomanipulatethecellularandviralpathwaysofgene
regulationbyencodingtheirownmiRNAs(19,24,26,42).
Amongthedifferentfamiliesofviruses,herpesviruseshave
exploitedthemiRNA-mediatedgeneregulationpathwaymost
successfully,since124ofthe127virus-encodedmiRNAsin
miRBaserelease10.1(http://microrna.sanger.ac.uk)areen-
codedbyherpesviruses.Ithasbeensuggestedthatthe
miRNA-mediatedregulatorymechanismsareverysuitedfor
theherpesviruslifecycle,whichischaracterizedbynuclear
replicationandlatentperiodswithminimalantigenexpression
(19).
SpecificmiRNAsignaturesindifferenttypesoftumorshave
beenidentifiedusinghigh-throughputmicroarrayanalysisof
miRNAexpression(60,64,67).Consideringtheaggressive
natureandrapidonsetoftumorsinducedbyMDV-1,analysis
ofthemiRNAprofileofMDV-transformedtumorcellscould
providefurtherinsightsintoMDoncogenesis.Previousstudies
usingsmallRNAsfromMDV-infectedchickenembryofibro-
blasts(CEF)haveidentifiedseveralmiRNAs,includingeight
MDV-encodedmiRNAsthatmappedtotheMeqandthe
latency-associatedtranscript(LAT)regionofthegenome(8,
9).AlthoughidentificationofMDVandhostmiRNAsinlyti-
callyinfectedCEFisvaluable,understandingtheexpression
profilesofmiRNAsinthelymphocytetargetcellsofMD
lymphomaswouldbecrucialtodelineatetheirrolein