学科分类
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89 个结果
  • 简介:TRAF2isacriticaladaptormoleculeforTNFreceptorsininflammatoryandimmunesignaling.Uponreceptorengagement,TRAF2isrecruitedtoCD40andtranslocatestolipidraftsinaRINGfinger-dependentprocess,whichenablestheactivationofdownstreamkinases.TRAF1candisplaceTRAF2andCD40fromraftfractions,anditpromotestheabilityofTRAF2tosustainsignalactivation.ReplacementoftheRINGfingerofTRAF2witharaft-targetingsignalrestoresJNKactivationandassociationwiththecytoskeletalproteinFilamin,butnotNF-KBactivation.TRAF1-/-dendriticcellsshowattenuatedresponses

  • 标签: TRAF2细胞内定位 TRAF1调节 信号转导机制
  • 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。

  • 标签: TRAIL 细胞毒性 抑制因子 肿瘤坏死因子相关凋亡诱导配体 人类 外周血单个核细胞
  • 简介:MembersofBcl-2familyofproteinsareregulatorsofcelldeaththatcanbegroupedintosubfamiliesofprosurvivalandproapoptoticmolecules.Theyarecharacterizedbythepresenceofseveralconservedmotifs,knownastheBcl-2homology(BH)domains,designatedBH1,BH2,BH3andBH4.MutagenesisandstructuralstudiesrevealedthattheBHdomainsareimportantfunctionaldomainsthatarealsorequiredfordimerizationfunction.Recently,asubfamilyofproapoptoticmoleculesonlycontainsBH3motifhasbeenidentifiedsuggestingBH3domainalonemaybesufficientformediatingproapoptoticfunctionamong

  • 标签: 前凋亡蛋白 map-1 多bcl-2同源域 bax相关蛋白 特性
  • 简介:细胞内部的氧化还原作用动态平衡在决定肿瘤房间的敏感到导致药的apoptosis起一个关键作用。这里,我们调查了thioredoxin-1(TRX1)的角色,氧化还原作用规定的一个关键部件,在砷三氧化物(作为(2)O(3))导致的apoptosis。在HepG(2)房间的野类型的TRX1的在表示上导致了抑制当(2)O(3)导致了细胞色素c(cytoc),释放,caspase激活和apoptosis,并且由RNAi的TRX1表示的绒毛规定敏化HepG(2)房间到当(2)O(3)导致了apoptosis。有趣地,到重量的单位(32/35)的从Cys(32/35)的TRX1的活跃地点的变化从一个apoptotic保护者把这个分子变换成一个apoptotic倡导者。以理解这变换的机制,我们从老鼠肝使用了孤立的线粒体并且发现了野类型的TRX1能保护的那重组体从apoptotic的线粒体变化。相反,TRX1的变异的形式独自得到了线粒体相关的apoptotic变化,包括mitochondrial渗透转变毛孔(mPTP)洞,mitochondrial膜潜力的损失,和cyto从线粒体的c版本。这些apoptotic效果被cyclosporineA(CsA)禁止,显示指向到mPTP的那变异的TRX1。到由2,4-dinitrochlorobenzene(DNCB)的氧化形式体内的从它的减少的形式的TRX1的改变,TRXreductase的一个特定的禁止者,也敏化的HepG(2)房间到当(2)O(3)导致了apoptosis。这些数据建议TRX1由任何一个变化在由堵住cytoc版本调整apoptosis,并且在TRX1的激活起一个中央作用或活跃地点半胱氨酸的氧化可以敏化肿瘤房间到当(2)O(3)导致了apoptosis。

  • 标签: 肝癌 三氧化砷 线粒体 细胞色素 细胞凋亡
  • 简介:hPFTAIRE1(PFTK1),Cdc2相关的蛋白质kinase,高度在人的大脑被表示。它在Hela房间展出细胞质的分发,尽管它在它的N终点包含二个原子本地化信号(NLS)。到为它的底层和规章的部件的搜索,我们由把全身的hPFTAIRE1用作一个诱饵屏蔽了一个二混血儿的图书馆。四14-3-3isoforms(贝它,epsilon,希腊语字母的第七字,字形物)被识别与hPFTAIRE1交往。我们在hPFTAIRE1发现了一个通常认为的14-3-3绑定一致主题(RHSSPSS),它与它的第二NLS重叠了。RHSSPSS主题的删除或有在保存有约束力的主题的翼的Ser119的替换废除了在hPFTAIRE1和14-3-3蛋白质之间的特定的相互作用。变异的S120AhPFTAIRE1也显示出一个弱相互作用到14-3-3蛋白质。结果建议Ser119为在hPFTAIRE1和14-3-3蛋白质之间的相互作用是关键的。当熔化了到绿荧光灯的蛋白质(GFP)的C终点时,所有hPFTAIRE1异种在Hela房间和人的neuroblastoma房间(SH-SY5Y)的细胞质散布了,显示有14-3-3蛋白质的那绑定不贡献潜水艇hPFTAIRE1的细胞的本地化,尽管绑定可以涉及它的发信号的规定。

  • 标签: 蛋白激酶 大脑 相互作用 蛋白质
  • 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.

  • 标签: 感应现象 HLA-G 基因表达 黑色素瘤 肿瘤细胞 OCM-1A
  • 简介:<正>Usingsubtractioncloning,weidentifiedthehumanN-MycDownstream-RegulatedGene-2(hNDRG2),locatedat14q11.2,asacandidatetumorsuppressorgene.Semi-quantitativeRT-PCRshowedthattheexpressionofhNDRG2in15of27(56%)humanGBMtissuesandall6humanglioblastomacelllineswassignificantlylowerthanthatinthenormalbrain.TheexpressionofhNDRG2alsowasevaluatedin60lung-carcinomapatients.17of26casesofsquamouscarcinomaand4of11casesofsmallcelllungcancerdisplayed

  • 标签: N-Myc减量调节基因2 NDRG2 细胞生长 负向调节 癌症 表达减少
  • 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.

  • 标签: 胞外基质 明胶酶原 细胞表面活化 细胞迁移
  • 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。

  • 标签: NANOG 哺乳动物胚胎 调控 转录因子 ICM 内细胞团
  • 简介:<正>Uponactivation,naiveT-helpercellscandifferentiateintotwomajordistinctsubsets,Thelper1(Th1)andThelper2(Th2),asdefinedbytheireffectorfunctionsandcytokinesecretionpatterns.CytokinemilieuandcostimulatorymoleculeshavebeenshowntoplayanessentialroleindeterminingThelperdifferentiation.However,itisstillunclearhowtheeffectsofsignalsofco-stimulatorymoleculesandcytokinesareexertedduringThelperdifferentiation.Weshowevidencesuggestingthatwhilecytokinesignalsinitiatedifferentiationprogram,theselectiveactionofdeatheffectorsdeterminestheendpointbalanceofdifferenti-

  • 标签: TH1细胞 TH2细胞 细胞凋亡 TRAIL CD95L 交互表达
  • 简介:ErbB2,amemberofthereceptortyrosinekinasefamily,isfrequentlyover-expressedinbreastcancer.ProteolysisoftheextracellulardomainofErbB2resultsinconstitutiveactivationofErbB2kinase.RecentstudyreportedthatErbB2isfoundinthenucleus.Here,weshowedthatErbB2isimportedintothenucleusthroughanuclearlocalizationsignal(NLS)-mediatedmechanism.TheNLSsequenceKRRQQKIRKYTMRR(aa655-668)containsthreeclustersofbasicaminoacidsanditissufficienttotargetGFPintothenucleus.However,mutationinanybasicaminoacidclusterofthisNLSsequencesignificantlyaffectsitsnuclearlocalization.Furthermore,itwasfoundthatthisNLSisessentialforthenuclearlocalizationofErbB2sincetheintracellulardomainofErb2lackingNLScompletelyabrogatesitsnucleartranslocation.Takentogether,ourstudyidentifiedanovelnuclearlocalizationsignalandrevealsanovelmechanismunderlyingErbB2nucleartraffickingandlocalization.

  • 标签: 核子定位 信号转导 ErbB-2蛋白质 酪氨酸激酶 乳腺癌
  • 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。

  • 标签: 水稻育种 直立穗 伸长率 生长 突变体 晶粒尺寸
  • 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.

  • 标签: 小鼠 两细胞胚胎 ZGA 阻抑
  • 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.

  • 标签: 肝素 凋亡 咽鼓管癌 CNE2细胞
  • 简介:Amurinemacrophage-likecelllineJ774,acquired,inresponsetoLPS,anabilitytokilltumornecrosisfactor(TNF)-insensitivetargetP815mastocytomacellswhereasanothercellline,P388D1didnot,LPStriggeredsignalingmechanismsbetweenthetwocelllineswerecomparedwithanaimtoinquireaboutthepossiblenatureoftheabove-mentioneddifference,TheresultswhowedthattwocelllinesrespondtoLPS-treatmentbyparallelactivationofbothphospholipasesCandA2(PLCandPLA2)toapproximatelythesameextent.ThemaximumresponseoftothenzymesofJ774cellswasnotedwithin10minthetreatmentwhereasthatofP388D1cellsrequiredmorethan20min,TheotherpropertiesofLPS-responsiveenzymesstudiedweresimilarbetweentwocelllines,includingActivationofPLCandPLA2andPKCinmacrophagesbyLPS.Ca2+augmentationofenzymeactivation,participationofguaninenucleotidebinding(G)proteinsintheinitialactivationpreocesses,andinhibitionofenzymeactivationbythepriortreatmentofcellswithcholeraorpertussistoxinsetc.Moreover,LPS-triggeredactivationofPLCandPLA2wasfoundtobefollowedbytheincreaseofPKCactivitiesinbothcelllines.Inspiteofthesesimilarities.J774cellspossessedbothbasicandacidicformsofPKCactivities,whileP388D1cellsownedonlyPKCofbasicform,Nevertheless,thequestionwhyJ774cellsbutnotP388D1cells,canacquirethetumoricidalactivity,aganistP815,cellsfollowingLPStreatmentrematinstobeanswered.

  • 标签: 鼠巨噬细胞细胞系 磷脂酶A2 磷脂酶C 蛋白激酶C LPS诱导激活
  • 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.

  • 标签: HL-60细胞 细胞凋亡 Bol-2 Caspase-3 半胱氨酸天冬氨酸蛋白酶 胞内钙分布
  • 简介:Polyamines在在植物,而是他们的准确角色调整各种各样的发展过程被含有并且他们怎么管理这些过程尚待逃犯。我们这里报导浓密的Arabidopsis和矮子异种,bud2,哪个从编码S-adenosylmethioninedecarboxylases(SAMDC)的小基因家庭的一个成员的完全的删除的结果为在polyamine简历的不可缺少的中介的形成必要合成小径。bud2植物在开花期,根,和叶柄扩大了脉管的系统,并且polyamines的改变的动态平衡。bud2和samdc1的双异种,另一个SAMDC成员的击倒的异种,是胚胎致命,证明SAMDC为植物胚胎开始是必要的。我们的结果建议polyamines为更高的植物的正常生长和发展被要求。

  • 标签: S-腺苷甲硫氨酸脱羧酶 基因编码 BUD2 植物构造