简介:目的研究阻断CD40-CD40L共刺激信号通路对移植皮肤免疫排斥反应的影响。方法通过RT-PCR技术克隆了呈可溶性表达的CD40L分子胞外区(sCD40L),利用K14启动子构建了sCD40L皮肤特异性表达载体,并利用该载体制备了转基因小鼠。结果所克隆的CD40L胞外区片段其大小及序列符合预期;以哺乳动物表达载体PCI为骨架,通过DNA重组,获得了含K14启动子和sCD40L编码区的皮肤特异性表达载体K14-sCD40L;通过显微注射和胚胎移植,PCR筛选检测:49只G0代小鼠有1只小鼠扩增出特异性条带,阴性对照无条带。结论成功建立sCD40L转基因阳性小鼠。
简介:Apoptosismanifestsintwomajorexecutionprogramsdownstreamofthedeathsignal:thecaspasepathwayandorganelledysfunction.Animportantantiapoptosisfactor,Bcl-2protein,contributesincaspasepathwayofapoptosis.Calcium,animportantintracellularsignalelementincells,isalsoobservedtohavechangesduringapoptosis,whichmaybeaffectedbyBcl-2protein.WehavepreviouslyreportedthatinHarringtonine(HT)inducedapoptosisofHL-60cells,there'schangeofintracellularcalciumdistribution,ovingfromcytoplastespeciallyGolgi'sapparatustonucleusandaccumulatingtherewiththehighestconcentration.Wereportherethatcaspase-3becomesactivatedinHT-inducedapoptosisofHL-60cells,whichcanbeinhibitedbyoverexpressionofBcl-2protein.NosignofapoptosisorintracellularcalciummovementfromGolgi'sapparatustonucleusinHL-60cellsoverexpressingBcl-2ortreatedwithAc-DEVD-CHO,aspecificinhibitorofcaspase-3.Theresultsindicatethatactivatedcaspase-2canpromotethemovementofintracellularcalciumfromGolgi'sapparatustonucleus,andtheprocessisinhibitedbyAc-DEVD-CHO(inhibitorofcaspase-3),andthatBcl-2caninhibitthemovementandaccumulationofintracellularcalciuminnucleusthroughitsinhibitiononcaspase-3.Calciumrelocalizationinapoptosisseemstobeirreversible,whichisdifferentfromtheintracellularcalciumchangescausedbygrowthfactor.
简介:试验用SSR分子标记对60份宁夏粳稻种质资源进行遗传多样性分析。103对SSR引物表现多态性的有58对,共扩增出212条多态性条带,等位变异范围为2~9,平均每对引物3.7个;多态性信息含量(PIC)变幅为0.032~0.788,平均为0.403;高多态性位点主要发生在3号、6号和11号染色体上,而无多态性或低多态性位点主要发生在1号和10号染色体上;成对供试材料的遗传相似系数GS值变幅为0.642~0.958,平均为0.790,单个供试材料的平均GS值变幅为0.710~0.816,平均为0.781,亲缘关系较近;UPGMA聚类表明,在遗传相似系数约0.785处,供试材料可被分为11类,大部分材料被聚在一类中。
简介:Theeventsofcelldeathandtheexpressionofnuclearmatrixprotein(NMP)havebeeninvestigatedinapromyelocyticleukemiccelllineHL-60inducedwithetoposide.BymeansofTUNELassay,thenucleidisplayedacharacteristicmorphologychange,andtheamountofapoptoticcellsincreasedearlyandreachedmaximunabout39%aftertreatmentwithetoposidefor2h.NucleosomalDNAfragmentationwasobservedaftertreatmentfor4h.ThemorphologicalchangeofHL-60cells,thus,occurredearlierthantheappearanceofDNAladder.Totalnuclearmatrixproteinswereanalyzedby2-dimensionalgelelectrophoresis.Differentialexpressionof59nuclearmatrixproteinswasfoundin4hetoposidetreatedcells.Westernblottingwasthenperformedonthreenuclearmatrixacssociatedproteins,PML,HSC70andNuMA.TheexpressionofthesuppressorPMLproteinandheatshockproteinHSC70weresignificantlyupregulatedafteretoposidetreatment,whileNuMA,anuclearmitoticapparatusprotein,wasdownregulated.Theseresultsdemonstratethatsignificantbiochemicalalterationsinnuclearmatrixproteinstakeplaceduringtheapoptoticprocess.
简介:TodeterminecancerpathwayactivitiesinninetypesofprimarytumorsandNCI60celllines,weappliedaninsilicoapproachbyexamininggenesignaturesreflectiveofconsequentpathwayactivationusinggeneexpressiondata.SupervisedlearningapproachespredictedthattheRaspathwayisactivein~70%oflungadenocarci-nomasbutinactiveinmostsquamouscellcarcinomas,pulmonarycarcinoids,andsmallcelllungcarcinomas.Incontrast,theTGF-β,TNF-α,Src,Myc,E2F3,andβ-cateninpathwaysareinactiveinlungadenocarcinomas.WepredictedanactiveRas,Myc,Src,and/orE2F3pathwayinsignificantpercentagesofbreastcancer,colorectalcarcinoma,andgliomas.OurresultsalsosuggestthatRasmaybethemostprevailingoncogenicpathway.Additionally,manyNCI60celllinesexhib-itedagenesignatureindicativeofanactiveRas,Myc,and/orSrc,butnotE2F3,β-catenin,TNF-α,orTGF-βpathway.Toourknowledge,thisisthefirstcom-prehensivesurveyofcancerpathwayactivitiesinninemajortumortypesandthemostwidelyusedNCI60celllines.The“geneexpressionpathwaysignatures”wehavedefinedcouldfacilitatetheunderstandingofmolecularmechanismsincan-cerdevelopmentandprovideguidancetotheselectionofappropriatecelllinesforcancerresearchandpharmaceuticalcompoundscreening.
简介:目的:构建汉滩病毒包膜糖蛋白基因的真核表达载体,并加入可增强免疫应答效应的细胞因子CD40L基因,检测其可否在真核细胞中表达。方法与结果:参照GenBank中汉滩病毒M基因和小鼠CD40L的全基因序列设计引物,通过聚合酶链反应(PCR)获得M和CD40L基因片段,将其与pCI—neo载体相连,测序证实该载体构建成功后,将此真核表达载体以脂质体转染法转染至哺乳动物细胞CHO—K1中,利用间接免疫荧光法(IFA)检测发现M基因和CD40L基因可以同时表达于CHO-K1细胞中。结论:构建了带有CD40L基因的汉滩病毒包膜糖蛋白重组质粒并获得表达,为深入研究汉滩病毒感染后包膜糖蛋白引起的特异性免疫应答规律奠定了实验基础。
简介:目的:利用Red系统构建肠出血性大肠杆菌O157:H7的sRNA基因E40缺失突变株。方法:选取本实验室预测并经过实验验证的sRNA基因,根据NCBI上相应的序列,设计2对引物分别扩增该sRNA基因的上下游分别长464和455bp的同源臂,经PCR扩增,构建到相应的载体,最后以构建好的含上下游同源臂和卡那霉素抗性基因的长约2500bp的线性片段作为打靶片段,在Red重组系统的作用下与sRNA基因E40的上下游同源区域发生同组,从而把sRNA基因从基因组上置换下来,之后利用质粒pCP20将FRT位点间的卡那霉素抗性基因消除。结果与结论:构建了出血性大肠杆菌O157:H7的sRNA基因E40的缺失突变株,为进一步研究sRNA基因在出血性大肠杆菌O157:H7生长及致病过程中所起的功能奠定了良好的基础。
简介:cAMPmediatedsignalingmayplayasuppressiveroleinimmuneresponse.WepreviouslyfoundthatthecAMP-elevators(CTxand8-Br-cAMP)inhibitedIL-12,IL-la,IL-6geneexpression,butincreasedthetranscriptionallevelsofIL-10andIL-1RainLPS-treatedmurineperitonealmacrophages.ThepresentstudyexaminedapossiblemolecularmechanisminvolvedincAMPelevators-inducedinhibitionofIL-12p40expressioninresponsetoLPS.OurdatademonstratedthatcAMPelevatorsdownregulatedIL-12p40mRNAexpressionandIL-12pT0productioninmurineperitonealmacrophages.SubsequentstudiesrevealedthatcAMP-elevatorsblockedphosphorylationofp38MAPK,butdidnotaffecttheactivityofNF-κBbindingtoIL-12promoter(-136/-112).ThisisthefirstreportthatcAMPelevatorsinhibitLPS-inducedIL-12productionbyamechanismthatisassociated,atleastinpart,withp38-dependentinhibitionbycAMPsignalingpathways.