70
scriptionandsynthesisoffirststrand.Andthenthefirststrand
,theamplificationwascarriedoutbythewasusedasatemplate
useoftheCMV2SP1/CMV2ASP2,CMV2SP3/CMV2ASP4ofthedesignprimersCMVRNA2,afterthesequencingoftheamplifiedsequence,theDNAMAN(Version5.2.2,Lynnon
)sequenceanalysissoftwarewasusedforsequenceBiosoft
[9]
analysisandevolutiontreeconstruction.PCRamplificationofRNAiinterferencefragments ThesequencedRNA2genomesequencewasanalyzedandtheconservedregionsindentifiedtodesignandsynthesizeprim,andthegenefragmentpreservedontheTvectorwasersusedasatemplate,thetwopairsofprimersCR2Kp/CR2SBandCR2Bg/CR2SBwereusedtoamplifytheinterferenceAgriculturalScience&TechnologyVol.11,No.5,2010
acidhomologywasof71.3%-98.8%and74.0%-98.5%
(Table3),inwhichtheNS04isolatehadhighhomologywithPhylineswhichwasfromZhejiangofChina,theGenbanknumberwasDQ412731(Fig.2),thenucleotideandamin
o
fragmentPCR_CR2_BKandPCR_CR2_SB.ConstructionofpBi35SCR2expressionvector AftertheamplifiedPCR_CR2_BKwasrecoveredwithBamHⅠandKpnⅠd
igestion,thecorrespondingdigestedpiRDG12siteswereinserted
,andthenthepiRD_CR2.Sfirstintermediatevectorwasobtained(Fig.1A).TheamplifiedPCR_CR2_SBwasrecoveredwithBglⅡandSacⅠd
igestion,andthecorrespondingdigestedpiRD_CR2.Ssiteswereinserted
,andthenthepiRD_CR2secondintermediatevectorwasgained(Fig.1B).AfterthepiRD_CR2vectorwasdigestedwithXbaⅠandEcoRⅠ,thesmallfragmentwasinsertedwiththecorrespondingsitesofdigestedpBi35SG12,andfinallythepBi35SCR2
expressionvectorwasobtained(
Fig.1C),thedesignofvectorwascompletedwithVectorNTIassist
.
Fig.1 ConstructionofpiRDCR2.S(A),piRDCR2(B)and
pBi35SCR2
(C)expressionvectorGenetictransformationtotobacco Theconstructed
pBi35SCR2expressionvectorwastransformedintoAgrobacteriumtumefaciensGV3101,theNicotianatobacco(Nt)leaveswerecutinto1cmofleafdisc,whichwerethenmixedwithAgrobacteriuminfectionliquidfor5-10minofsoaking,the
excessbacterialiquidwasremovedanddried,andthentheywereplacedonthecoculturemedium(
MS+0.5mg/Lof6BA),aftercultivatedindarkfor1-3d,theyweretrans
ferredtothedifferentiationmedium(
MS+0.5mg/Lof6BA+50.0mg/Lof
Kan+300.0mg/LofCar)fortheinductionofregenerationbud.Whentheregeneratedshootlengthwasabout1.5-2.0cm,theregenerationshootwascutoffand
transferredtorootingmedium(
MS+0.1mg/LofIAA+50.0mg/LofKan+300.0mg/LofCar)fortheinductionofroots.
ResultsandAnalysis
CloningandsequenceanalysisofCMVRNA2genome
PrimersCMV2SP1/CMV2ASP2,CMV2SP3/CMV2ASP4
wereusedtoamplifythefragmentsof1553and1378bp
,afterthealignmentsandsplicing,partsofCMVRNA2genomicfragmentwith2864bpwereobtained,andthesepartscontainedthenucleotidesequencewhichcouldencodeCMV2a
replicaseproteinandCMV2bprotein
,bytheuseofDNAMANsoftware,thecomparisonofCMV2afragmentsofNS04isolateandotherisolates(GenbanknumberandoriginwereshowninTable2)suggestedthattheirnucleotideandamino
Fig.2 PhylogenetictreeofthenucleotidesequenceofCMV
2aisolates
acidhomologywere98.0%and96.5%respectively.
Table2 TheGenbanknumberofdifferentCMVisolationsGenbanknumberOrigin
IsolationsAB368500JapanCMVPfAB079890JapanCMV36a1AB179765JapanCMVD8AB368497JapanCMV42CMDQ399549ZhejiangProvinceofChinaCMVBXDQ412731ZhejiangProvinceofChinaCMVPhyEF213024ZhejiangProvinceofChinaCMVCTLAM183115SpainCMVPl1AB183118SpainCMVRi8EF202596ZhejiangProvinceofChinaCMVTshD10209JapanCMVOD86330BeijingofChinaCMVSDEU665001BeijingofChinaUnknownS72187UnknownCMVKEU723570ZhejiangProvinceofChinaCMVPHzFJ268745ZhejiangProvinceofChinaCMVCah1AJ276480
Korea
CMVMf
PCRamplificationofinterferingfragments
ThesequencewhichwasconnectedtotheTcloningvectorandhadcorrectalignmentwiththeNCBIdatabasedatawasusedasthetemplate.Bytheuseofthedesignedprimers
CR2Kp/CR2SBandCR2Bg/CR2SB
,thePCR_CR2_BKfragmentwith693bpandPCR_CR2_SBfragmentwith741bpwereamplified(Fig.3,4).ThetwoendsofthePCR_CR2
BKwereintroducedtworestrictionsitesofBamHⅠandKpnⅠ
,whileBglⅡandSacⅠrestrictionsiteswereintroducedtothetwoendsofPCR_CR2_SBtofacilitatetheconstructionoffollowupvector.ConstructionandidentificationofpBi35SCR2expressionvector
AftertheconnectionofPCRCR2BKandpiRDG12,a
4763bpofpiRDCR2.Sintermediatevectorwasobtained
,therewasaClaIrestrictionsiteintheconnectedPCRCR2BKfrag
ment,anda4763bpbandwasgainedbysingleenzymedigestion,indicatingthatPCRCR2BKhadconnectedwiththevector(Fig.5).AftertheconnectionofPCRCR2SBfragmentsandintermediatevectorpiRDCR2.S,piRDCR2wasobtained,finally