简介:流行性感冒的所有已知的子类型A病毒在野水鸟被维持,这些病毒的自然水库。流行性感冒A病毒被孤立从许多有改变病态和死亡率的动物种类。更重要地,流行性感冒A病毒与潜在地致命的结果在人引起呼吸疾病。在人的本地或全球的爆发被过量住院和死亡典型地描绘。在1997,H5N1子类型的高度病原的鸟的流行性感冒病毒在传给人的香港出现了,导致由鸟的流行性感冒病毒感染的人的死亡的首先记录的盒子。在越南,印度尼西亚,和泰国在家禽在2003年7月开始的新爆发,和高度病原的鸟的H5N1流行性感冒病毒后来在整个亚洲并且进欧洲和非洲传播了。这些病毒继续与高死亡率感染人并且引起隐约可见的世界范围的担心流行。而且,H5N1病毒爆发在整个亚洲在家禽工业上有破坏效果。因为H5N1病毒爆发看起来从南部的中国发源,我们这里在中国检验H5N1流行性感冒病毒,与他们的生物性质上的一个重音。
简介:Thenon-classicalHLAclassIantigenHLA-GisanimmunemodulatorwhichinhibitsthefunctionsofTcells,NKcells,andtheDendriticcells(DC).Asaresult,HLA-Gexpressioninmalignantcellsmayprovidethemwithamechanismtoescapetheimmunesurveillance.Inmelanoma,HLA-Gantigenexpressionhasbeenfoundin30%ofsurgicallyremovedlesionsbutinlessthan1%ofestablishedcelllines.OnepossiblemechanismunderlyingthedifferentialHLAGexpressioninvivoandinvitroisthattheHLA-Ggeneisepigeneticallyrepressedinmelanomacellsinvitro.Totestthishypothesis,wetreatedtheHLA-GnegativemelanomacelllineOCM-1AwiththeDNAmethyltransferaseinhibitor5-aza-2'-deoxycytidine(5-AC)andanalyzedwhetherHLA-Gexpressioncanberestored.OurdatastronglysuggestthatHLA-GissilencedasaresultofCpGhypermethylationwithina5'regulatoryregionencompassing220bpupstreamofthestartcodon.Aftertreatment,HLA-GmRNAexpressionwasdramaticallyincreased.WesternblotandflowcytometryshowedthatHLA-Gproteinwasinduced.Interestingly,HLA-Gcellsurfaceexpressiononthe5-ACtreatedOCM-1AcellsismuchlessthanthatontheHLA-GpositiveJEG-3cellswhileasimilaramountoftotalHLA-Gwasobserved.Possiblemechanismsforthedifferencewereanalyzedinthestudysuchascellcold-treatment,peptideloadingandantigenprocessingmachinerycomponents(APM)aswellasβ2microglobulin(β2-m)expression.DatarevealedthattheAPMcomponentcalreticulinmightbeinvolvedinthelowerHLA-GsurfaceexpressiononOCM-1Acells.Takentogether,ourresultsindicatedthatDNAmethylationisanimportantepigeneticmechanismbywhichHLA-Gantigenexpressionismodulatedinmelanomacellsinvitro.Furthermore,tothefirsttime,wehypothesizedthatthedeficiencyofcalreticulinmightbeinvolvedinthelowHLA-Gsurfaceexpressiononthe5-ACtreatedOCM-lAcells.
简介:组蛋白甲基化是参予细胞的过程的一个多样的数组的重要epigenetic现象并且被发现了与癌症被联系。几的Recentidentification嘘一demethylases证明了那嘘一甲基化是一个可逆过程。通过一条候选人途径,我们化学上有简历作为H3K27demethylase识别了JMJD3。进HeLa房间的JMJD3的Transfection引起了整齐的乙醇H3K27的特定的减小,但是没在di-和单音的甲基H3K27上有效果,或嘘H3K4和H3K9上的一离氨酸methylations。Theenzymatic活动要求JmjC域和被建议了为余因子绑定重要的保存组氨酸。试管内生物化学的实验证明那JMJD3directly催化demethylation。另外,我们发现JMJD3起来在前列腺癌症,和它的表示调整了在变形前列腺癌症是更高的。因此,我们作为能够把整齐的乙醇组从移开的ademethylase识别了JMJD3嘘一H3离氨酸27并且起来在前列腺癌症调整了。
简介:ToexplorethemolecularmechanismofchromatinremodelinginvolvedintheregulationoftranscriptionalactivationofspecificgenesbyamyogenicregulatoryfactorMyogenin,weusedNIH3T3fibroblastswithastablyintegratedH1.1-GFPfusionproteintomonitorhistoneH1movementdirectlybyfluorescencerecov-eryafterphotobleaching(FRAP)inlivingcells.TheobservationfromFRAPexperimentswithmyogenintransfectedfibroblastsshowedthattheexchangerateofhistoneH1inchromatinwasobviouslyincreased,indicatingthatforcedexpressionofexogenousMyogenincaninducechromatinremodeling.Thehyper-acetylationofhistonesH3andH4frommyogenintransfectedfibroblastswasdetectedbytriton-acid-urea(TAU)/SDS(2-D)electrophoresisandWesternblotwithspecificantibodiesagainstacetylatedN-terminiofhistonesH3andH4.RT-PCRanalysisindicatedthatthenAChRa-subunitgenewasexpressedinthetrans-fectedfibroblasts.TheseresultssuggestthattheexpressionofexogenousMyogenincaninducechromatinremodelingandactivatethetranscriotionofMvogenin-targetedgeneinnon-musclecells.
简介:Thebindingofnuclearproteinspreparedfrommouseerythroidtissueindifferentdevelopmentalstagestothe5'-flankingregulatoryelementsofhumanβ-globingene,twonegativecontrolregions(NCR1,-610to-490bp;NCR2,-338,to-233bp),wasidentified.TwostagespecificproteinfactorscorrespondingtoembryonicandfetalstageswerefoundtobecapableofbindingtoNCR2.Thesedataprovidedevidencethatthecisactingelementsofthe5'-flankingregionmightbeinvolvedinthedevelopmentalcontrolofβ-globingeneandNCR2mightberesponsibleinartforthesilenceofβ-glolbingeneintheembryonicandfetalstages.
简介:MicroRNAs(miRNA)指导在基因表示的一个重要角色在植物为到环境条件的发展进程和回答要求了的顺序特定的posttranscriptional基因silencing玩。然而,很少对transcriptional和miRNA表示的posttranscriptional规定被知道。Histoneacetylation在染色质改变起一个重要作用并且为基因激活被要求。由在Arabidopsis的异种分析miRNAs和相应主要miRNAs的子集的累积,我们显示出那histoneacetyltransferaseGCN5(一般控制非镇压的protein5)在miRNA上有一般压抑的效果生产,当它为一个子集的表示被要求时(例如压力可诱导)MIRNA基因。在miRNA生产的GCN5的一般否定功能多半通过象DICERLIKE1(DCL1)那样的miRNA机械基因的间接压抑被完成,有锯齿(SE),偏下性的LEAVES1(HYL1)和ARGONAUTE1(AGO1)。染色质immunoprecipitation试金表明GCN5指向到MIRNA基因的一个子集并且为在这些loci的histoneH3离氨酸14的acetylation被要求。而且,由trichostatin的histonedeacetylation的抑制一个处理或在histonedeacetylase,基因异种损害了某些miRNAs的累积。这些数据一起建议ArabidopsisGCN5在transcriptional和posttranscriptional层次防碍miRNA小径,histoneacetylation/deacetylation是涉及miRNA的规定的epigenetic机制生产。
简介:Xenopusorganizerspecificgenenogginpossessesnearlyallthecharacteresticpropertiesoftheactionoforganizertospecifytheembryonicbodyacis.Toanalyzehowthematernalinheritedfactorscontrolitsexpressionpattern,weclonedthe5'regulatoryregionofnoggingene.The1.5kbupstreamsequensecoulddirectreportergenetoexpressinvivoanddatafromdeletionanalysisindicatedthata229basepairfragmetisessentialforactivatingnogginexpression.WefurtherdemonstratedthattheresponseelementswithinthisregulatoryregionwereindeedunderthecontrolofgrowthfactoractivinandWntsignalingpathwaycomponents.
简介:TRAF2isacriticaladaptormoleculeforTNFreceptorsininflammatoryandimmunesignaling.Uponreceptorengagement,TRAF2isrecruitedtoCD40andtranslocatestolipidraftsinaRINGfinger-dependentprocess,whichenablestheactivationofdownstreamkinases.TRAF1candisplaceTRAF2andCD40fromraftfractions,anditpromotestheabilityofTRAF2tosustainsignalactivation.ReplacementoftheRINGfingerofTRAF2witharaft-targetingsignalrestoresJNKactivationandassociationwiththecytoskeletalproteinFilamin,butnotNF-KBactivation.TRAF1-/-dendriticcellsshowattenuatedresponses
简介:<正>Usingsubtractioncloning,weidentifiedthehumanN-MycDownstream-RegulatedGene-2(hNDRG2),locatedat14q11.2,asacandidatetumorsuppressorgene.Semi-quantitativeRT-PCRshowedthattheexpressionofhNDRG2in15of27(56%)humanGBMtissuesandall6humanglioblastomacelllineswassignificantlylowerthanthatinthenormalbrain.TheexpressionofhNDRG2alsowasevaluatedin60lung-carcinomapatients.17of26casesofsquamouscarcinomaand4of11casesofsmallcelllungcancerdisplayed
简介:Hybridoma房间在抗体生产率追随者暴露显示增加到张力亢进的条件。然而,内在的机制很好没被理解。在现在的学习,我们假设激活的T房间的原子因素5(NFAT5)/tonicityenhancer绑定蛋白质(TonEBP)工作增加hybridomacells的抗体生产率。NFAT5是osmosensitive哺乳动物的抄写因素。然而,它在没在张力亢进的周围被洗的各种各样的器官的无所不在的表示建议NFAT5可以也在等渗的条件下面调整细胞生长和功能。在这研究,我们由西方的污点分析在hybridoma房间检验了表示ofNFAT5,并且发现它在张力亢进的媒介显著地增加了。为了推进,在hybridoma房间定义NFAT5的功能,RNA干扰技术习惯于down在SGB-8房间(一根hybridoma房间线)调整NFAT5的表示。在等渗的媒介,hybridoma房间的抗体生产率被NFAT5while的down规定减少细胞增殖没被影响。这里介绍的结果表明那NFAT5不仅在hybridoma房间在渗透的压力反应小径起一个重要作用而且为最佳的抗体生产率是必要的。
简介:GelatinaseA(MMP-2)isconsideredtoplayacriticalroleincellmigrationandinvasion.Theproteinaseiscercetedfromthecellasaninactivezymogen.InvivoitispostulatedthatactivationofprogelationaseA(proMMP-2)takesplaceonthecellsurfacemediatedbymembrane-typematrixmetalloproteinases(MT-MMPs).RecentstudieshavedemonstratedthatproMMP-2isrecruitedtothecellsurfacebyinteractingwithtissueinhibitorofmetalloproteinases-2(TIMP-2)boundtoMT1-MMPbyformingaternarycomplex.FreeMT1-MMPcloselylocatedtotheternarycomplexthenactivatesproMMP-2onthecellsurface.MT1-MMPisfoundinculturedinvasivecancercellsattheinvadopodia.TheMT-MMP/TIMP-2/MMP-2systemthusprovideslocalizedexpressionofproteolysisoftheextracellularmatrixrequiredforcellmigration.
简介:在哺乳动物的胚胎,内部房间团(ICM)的分离和trophectoderm(TE)的第一种房间命运选择,,被抄写因素,Oct4和Cdx2的互相对抗的效果调整pluripotency因素,Nanog,是必要的指定epiblast。我们分析了Nanog和Cdx2的倡导者,并且发现了这二个抄写因素同样相互地被调整。用有有条件的TE区别的一根胚胎的干细胞线,我们证明Nanogoverexpression压制TE标记的upregulation,当时Nanog击倒的upregulatesTE标记的表示。我们推进Nanog和Cdx2绑在并且镇压的表演对方的倡导者。而Nanog大美人在ICM导致可检测的Cdx2表示,我们不管多么不观察胚囊开发的公开混乱,显示Nanog起到在ICM和TE的分离的Oct4的一个谄媚的作用。
简介:ErbB2,amemberofthereceptortyrosinekinasefamily,isfrequentlyover-expressedinbreastcancer.ProteolysisoftheextracellulardomainofErbB2resultsinconstitutiveactivationofErbB2kinase.RecentstudyreportedthatErbB2isfoundinthenucleus.Here,weshowedthatErbB2isimportedintothenucleusthroughanuclearlocalizationsignal(NLS)-mediatedmechanism.TheNLSsequenceKRRQQKIRKYTMRR(aa655-668)containsthreeclustersofbasicaminoacidsanditissufficienttotargetGFPintothenucleus.However,mutationinanybasicaminoacidclusterofthisNLSsequencesignificantlyaffectsitsnuclearlocalization.Furthermore,itwasfoundthatthisNLSisessentialforthenuclearlocalizationofErbB2sincetheintracellulardomainofErb2lackingNLScompletelyabrogatesitsnucleartranslocation.Takentogether,ourstudyidentifiedanovelnuclearlocalizationsignalandrevealsanovelmechanismunderlyingErbB2nucleartraffickingandlocalization.
简介:包括谷物尺寸和圆锥花序形态学,圆锥花序的建筑学直接决定谷物产量。圆锥花序直立,为在中国的北部分完成理想的植物建筑学被选择,引起了米饭breeders的增加的注意。这里,稠密、直立的圆锥花序2(dep2)异种,显示出稠密、直立的圆锥花序显型,被识别。没有任何已知的功能的领域,DEP2编码植物特定的蛋白质。表示介绍DEP2表明它高度在年轻纸巾被表示,与在年轻圆锥花序的大多数丰富。词法并且表示分析显示在DEP2的那个变化主要影响脊柱和主要、第二等的分支的快速的延伸,但是不损害圆锥花序primordia的开始或形成。进一步的分析建议在dep2的圆锥花序长度的减少被一个缺点在圆锥花序的指数的延伸期间在房间增长引起。尽管有在dep2异种的一种更紧缩的植物类型,在谷物生产的重要改变都没在野类型和dep2异种之间被发现。因此,DEP2的学习不仅加强我们圆锥花序建筑学的分子的基因基础的理解而且为米饭繁殖有重要含意。
简介:One-cellmouseembryosfromKMstrainandB6C3F1strainwereculturedinM16medium,inwhich2-cellblockgenerallyoccurs.EmbryosofKMstrainexhibited2-cellblock,whereasB6C3F1embryos,whichareregardedasanonblockingstrain,proceededtothe4-cellstageinourculturecondition.Itisoftenassumedthattheblockofearlydevelopmentisduetothefailureofzygoticgeneactivation(ZGA)inculturedembryos.Inthisstudyweexaminedproteinsynthesispatternsbytwo-dimensionalgelelectrophoresisof[35S]methionineradiolabeled2-cellembryos.Embryosfromtheblockingstrainandthenonblockingstrainwerecomparedintheirdevelopmentbothinvitroandinvivo.ThedetectionofTRCexpression,amarkerofZGA,at42hposthCGinKMembryosdevelopedinvitrosuggestedthatZGAwasalsoinitiatedeveninthe2-cellarrestedembryos.Nevertheless,asignificantdelayofZGAwasobservedinKMstrainascomparedwithnormallydevelopedB6C3F1embryos.AttheverybeginningofmajorZGAasearlyas36hposthCG,TRChasalreadybeenexpressedinB6C3F1embryosdevelopedinvitroandKMembryosdevelopedinvivo.Butfor2-cellblockedKMembryos,TRCwasstillnotdetectableevenat38hposthCG.Theseevidencessuggestthat2-cell-blockedembryosdoinitiateZGA,andthat2-cellblockphenomenonisduenottothedisabilityininitiatingZGA,buttoadelayofZGA.
简介:Inordertostudythemechanismoftheeffectofheparinonapoptosisincarcinomacells,thenasopharyngealcarcinomacelllineCNE2wasusedtoidentifytheeffectofheparinonapoptosisassociatedwiththeexpressionofc-myc,bax,bcl-2proteinsbyuseofHoechst33258staining,terminaldeoxynucleotidyltransferase-mediateddUTPnick-endlabeling(TUNEL),agarosegelelectrophoresis,andflowcytometry,aswellasWesternblotanalysis.TheresultsshowedthatheparininducedapoptosisofCNE2cellsincludingthemorphologicchangessuchasreductioninthevolume,andthenuclearchromatincondensation,aswellasthe“ladderpattern”revealedbyagarosegelelectrophoresisofDNAinaconcentration-dependentmanner.ThenumberofTUNEL-positivecellswasdramaticallyincreasedto33.6±1.2%from2.8±0.3%bytreatmentwithheparinindifferentconcentrations(10~40kU/L).Theapoptoticindexwasincreasedto32.5%from3.5%bydetectingSubG1peaksonflowcytometry.Westernblotanalysisshowedthatlevelsofbcl-2,baxandc-mycweresignificantlyoverexpressedbytreatmentwiththeincreaseofheparinconcentrations.TheseresultssuggestthatheparininducesapoptosisofCNE2cells,whichmayberegulatedbydifferentialexpressionofapoptosis-relatedgenes.
简介:Thenuclearmatrixattachmentregions(MARs)andthebindingnuclearmatrixproteinsinthe5'-flankingcisactingelementsofthehumanε-globingenehavebeenexamined.UsinginvitroDNA-matrixbindingassay,ithasbeenshownthatthepositivestage-specificregulatoryelement(ε-PREII,-446bp--419bp)upstreamofthisgenecouldspecificallyassociatewiththenuclearmatrixfromK562cells,indicatingthatε-PREIImaybeanerythroidspecificfacultativeMAR.IngelmobilityshiftassayandSouthwesternblottingassay,anerythroid-specificnuclearmatrixprotein(ε-NMPk)inK562cellshasbeenrevealedtobindtothispositiveregulatoryelement(ε-PREII).Furthermore,wedemonstratedthatthesilencer(-392bp--177bp)upstreamofthehumanε-globingenecouldassociatewiththenuclearmatricesfromK562,HELandRajicells.Inaddition,thenuclearmatrixproteinspreparedfromthesethreecelllinescouldalsobindtothissilencer,suggestingthatthissilencerelementmightbeaconstitutivenuclearmatrixattachmentregion(constitutiveMAR).Ourresultsdemonstratedthatthenuclearmatrixandnuclearmatrixproteinsmightplayanimportantroleintheregulationofthehumanε-globingeneexpression.
简介:导致死亡的肿瘤坏死的能力因素相关的导致apoptosisligand(小道)大部分被描述了有选择地杀死许多癌症房间,但是有治疗的主要担心之一是药抵抗和可能的有毒的副作用的出现。这里,我们报导那条小道在Jurkat和SUPT1T房间线并且在人的高强风然而并非在健康的导出题目的外部血mononuclear房间导致apoptosis。在平行,有小道和Tyrphostin(AG-490)的治疗,选择Januskinase2禁止者,生产cytotoxicity的明显的改进,与控制相比或到由Stat3phosphorylation的重要抑制描绘了落后于独自一个对待的样品,并且与cIAP-1和cIAP-2mRNA层次的戏剧的减少联系了。由特定的小干扰RNA的cIAP-1和cIAP-2的Downregulation显著地放大减少小道的cytotoxicity。所有一起,这些调查结果强烈显示cIAP-1和cIAP-2downregulation是在调停的发信号的小径的基本的步T上的小道和AG-490的组合效果房间白血病。这些调查结果可以帮助在小道敏感的白血病影响的病人的治疗为不太有毒的药理学策略的发展打开新线路。
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.