学科分类
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55 个结果
  • 简介:在脂肪和肌肉房间,刺激胰岛素的葡萄糖举起被葡萄糖transporter主要调停4(GLUT4),哪个到响应胰岛素刺激的房间表面的从细胞内部的分隔空间的translocates。AS160是Akt的底层之一并且在调整胰岛素的GLUT4translocation起重要作用。在这研究,(RUVBL2)象RuvB一样蛋白质2用与集体spectrometry相结合的哺乳动物的双人脚踏车亲密关系纯化(龙头)作为新AS160有约束力的蛋白质被识别。在3T3-L1adipocytes,RUVBL2高度被表示并且在cytosol主要是分布式的。在adipocytes的RUVBL2的弄空通过减少刺激胰岛素的AS160phosphorylation禁止刺激胰岛素的GLUT4translocation和葡萄糖举起。然而,人的RUVBL2的介绍能颠倒这禁止的效果。这些数据建议RUVBL2通过它和AS160的相互作用在刺激胰岛素的GLUT4translocation起一个重要作用。

  • 标签: 结合蛋白 转位 葡萄糖转运体 串联亲和纯化 脂肪细胞 肌肉细胞
  • 简介:POU抄写因素OCT4不仅在维持pluripotent和房间而且幕作为通过基因剂量的一个房间命运决定因素完成的胚胎的茎(ES)的自我更新的状态起一个必要作用。然而,控制细胞内部的OCT4蛋白质水平的分子的机制留下逃犯。这里,我们报导那人的WWP2,E3ubiquitin(Ub)蛋白质ligase,通过它的WW领域明确地与OCT4交往并且在vitro并且在vivo提高OCT4的Ub修正。我们首先证明在人的ES房间的内长的OCT4能被Ubpost-translationally修改。而且,我们发现WWP2以一种剂量依赖者方式,和WWP2的活跃地点半胱氨酸残余通过26Sproteasome支持了OCT4的降级在OCT4上为它的酶的活动和解朊的效果被要求。显著地,我们当WWP2表示是由特定的RNA干扰(RNAi)的downregulated时,内长的OCT4蛋白质水平显著地被提高的数据表演,建议那WWP2是为在人的ES房间维持合适的OCT4蛋白质水平的一个重要管理者。而且,北污点分析证明WWP2抄本在多样的人的织物/器官是广泛地在场的并且高度在无差别的人的ES房间表示了。然而,它的表示水平快速在区分的人的ES房间以后被减少,显示WWP2表示力量发展地被调整。我们的调查结果证明WWP2是在人的ES房间的OCT4蛋白质水平的一个重要管理者。

  • 标签: 人类胚胎干细胞 转录因子 退化 蛋白质水平 Northern 半胱氨酸残基
  • 简介:Mammaliancelltotipotencyisasubjectthathasfascinatedscientistsforgenerations.AlonglastingquestionwhethersomeofthesomaticcellsretainstotipotencywasansweredbythecloningofDollyattheendofthe20thcentury.Thedawnofthe218thasbroughtforwardgreatexpectationsinharnessingthepoweroftotipotentcyinmedicine.Throughstemcellbiology,itispossibletogenerateanypartsofthehumanbodybystemcellengineering.Considerableresourceswillbedevotedtoharnesstheuntappedpotentialsofstemcellsintheforeseeablefuturewhichmaytransformmedicineasweknowtoday.Atthemolecularlevel,totipotencyhasbeenlinkedtoasingulartranscriptionfactoranditsexpressionappearstodefinewhetheracellshouldbetotipotent.NamedOct4,itcanactivateorrepresstheexpressionofvariousgenes.Curiously,verylittleisknownaboutOct4beyonditsabilitytoregulategeneexpression.ThemechanismbywhichOct4specifiestotipotencyremainsentirelyunresolved.Inthisreview,wesummarizerethestructureandfunctionofOct4andaddresstoOct4functioninmaintainingtotipotencyorpluripotencyofembryonicstemcels.

  • 标签: 干细胞 全能性 复制 翻译 蛋白因子
  • 简介:InteractionbetweencytotoxicTlymphocyte-associatedantigen-4(CTLA4,CD152)andB7molecules(B7-1andB7-2)isofimportanceinthecellulareventsoflymphocyte,includingantigen-specificT-cellactivationandinductionofautoreactiveT-cell.WedescribehaerethefirstintroductionofamurinesolubleCTLA4gene,CTLA4Ig,toMm1cells,amacrophagiccellline.CTLA4IgwassuccessfullyexpressedonMm1cellsandtheexpressedCTLA4IgwasfoundtobefunctionallyactiveintheirbindingtoB7moleculesbyflowcytometryandimmunofluorescencestudies.ThebiologicalactivityofCTLA4IgfromthetransfectedMm1cellswasstudiedandshowedinhibitoryactivityonmixedlymphocyteculture.AhighCTLA4Igproducingmacrophagiccelllinewasobtained.AsMm1cellswereregardedasdifficultforgenetransfectionandtherehassofarbeennoreportonexpressionofCTLA4IggeneonMm1cells,theseresultssuggestedthattheCELA4IgexpressingMm1cellscouldbeusefulforanalysisofCTLA4andB8moleculeinteractioninbothmacrophageandT-cell.

  • 标签: T淋巴细胞相关抗原4 细胞毒 可溶型 巨噬细胞 生物学活性 表达
  • 简介:Trichosanthin(TCS)isapotentallergentomice.Accordingtoourpreviousexperiments,itcouldbringouttheIgEresponsetoovabumin(OVA)ifTCSwasgivenonedaybeforeOVAimmunization,whileOVAalonecouldnotinduceIgEtoit.Inthiswork,thekineticsofinterleukin4(IL-4)andinterferonγ(IFN-γ)geneexpressioninthemesentericlymphnode(MLN)ofTCS-immunizedmicewasinvestigatedusingasemi-quantitativeRT-PCRmethod.ItindicatedthatTCSinducedsignificantIL-4geneexpressionandthepeaksofIL4geneexpressionwereondayoneafterTCSimmunizationinbothprimaryandsecondaryresponse.Incontrast,theIFN-γgeneexpressionwassuppressed.Furthermor,theIL-4geneexpressioninthesecondaryresponsewaslowerthanthatintheprimaryresponse.ThusthepresenceofIgEmemoryBcellswerestudied.ResultsshowedthattheamountofmatureIgEmRNAarosesignificantlyandrapidlyonedayafterTCSrestimulation,whileintheMLNofthemiceprimed30daysbeforeandwithoutboost,itwasalmostasthesameamountoftheunimmunizedcontrol.ThesefindingssuggesttheexistenceoftheIgEmemoryBcellsinthemiceaftertheprimaryTCSimmunization.

  • 标签: IL-4 IFN-γ Trichosansin 小鼠 免疫反应 基因表达
  • 简介:Asimplemethodtocreateachromosome-specificDNAlibrqaryofrice,includingmicrodissection,amplification,charterizationandcloning,isdescribed.Ricechromosome4fromametaphasecellhasbeenisolatedandamplifiedbytheLinkerAdapterPCR(LA-PCR).ThePCRproductswerelabeledasprobeswithDIG-11-dUTPusingtherandomprimingmethod.SouthernblotanalysiswithricegenomicDNAandspecificRFLPmarkersdemonstratedthatthePCRproductswerederivedfromricechromosome4.Alargelibrarycomprisingover100,000recombinantplasmidmicroclonesfromricechromosome4wasconstructed.Colonyhybridizationshowedthat58%oftheclonescontainedsingleorlow-copysequencesand42%containedrepetitivesequences.ThesizeofinsertsgeneratedbyPCRrangedfrom140bpto500bp.ThismethodwillfacilitatecloningofthespecificchromosomeDNAmarkersandimportantgenesofrice.

  • 标签: 水稻 第4号染色体 DNA文库 LA-PCR 显微解剖
  • 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:Interleukin-4isacytokineproducedbyactivatedTcells,mastcells,andbasophilsthatelicitsmanyimportantbiologicalresponses[1](seeTab1).TheseresponsesrangefromtheregulationofhelperTcelldifferentiation[2]andtheproductionofIgE[3]totheregulationoftheadhesivepropertiesofendothelialcellsviaVCAM-1[4],Inkeepingwiththesediversebiologicaleffects,high-affinitybindingsitesforIL-4(Kd20to300pM)havebeendetectedonmanyhematopoieticandnon-hematopoieticcelltypesatlevelsrangingfrom50to5000sitespercell[5].ThisreviewwillfocusonthediscretesignaltransductionpathwaysactivatedbytheIL-4recxeptorandthecoordinationoftheseindividualpathwaysintheregulationofafinalbiologicaloutcome.

  • 标签: 白介素-4 基因表达 生长 细胞存活 调节 生物学作用
  • 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:Perforin是主要从事调停的形成毛孔的蛋白质目标T房间死亡并且被细胞毒素的T淋巴细胞(CTL)和自然漂亮房间采用。然而,它是否也在常规CD4+T房间功能起一个作用,仍然保持不清楚。这里,我们报导那在perforin缺乏(PKO)老鼠,CD4+T房间是响应T的hyperproliferative房间受体(TCR)刺激。hyperproliferation的这个特征被改进在房间分割并且在IL-2分泌物伴随。看起来,perforin缺乏不在胸腺怒气和淋巴节点影响T房间开发。在vivo,perforin缺乏导致增加的抗原特定的T房间增长和抗体生产。而且,PKO老鼠更产生试验性的自体免疫的眼色素层炎。探讨分子的机制,我们发现在TCR刺激以后,从PKO老鼠的CD4+T房间显示增加的细胞内部的钙流动并且随后提高抄写因素NFAT1的激活。我们的结果显示perforin在由影响TCR依赖的Ca2+发信号调整CD4+T房间激活和有免疫力的反应起一个否定作用。

  • 标签: T细胞活化 CD4 钙信号 穿孔 细胞毒性T淋巴细胞 T细胞受体
  • 简介:IL-16isaligandandchemotacticfactorforCD4+Tcells.IL-16inhibitstheCD3mediatedlymphocyteactivationandproliferation.TheeffectsofIL-16onthetargetcellsaredependentonthecelltype,thepresenceofco-activatorsetc.TounderstandtheregulationfunctionandmechanismofIL-16ontargetcells,weuseda130a.a.recombinantIL-16tostudyitseffectsonthegrowthofJurkatTleukemiacellsinvitro.WefoundthattherIL-16stimulatedtheproliferationofJurkatcellsatlowdose(10^-9M),butinhibitedthegrowthofthecellsathigherconcentration(10^-5M).Resultsshowedthat10^-5MofrIL-16treatmentinducedanenhancedapoptosisinJurkatcells.ThetreatmentblockedtheexpressionofFasL,butup-regulatedthec-mycandBidexpressioninthecells.Pre-treatmentofPKCinhibitororMEK1inhibitormarkedlyincreasedordecreasedtherIL-16inducedgrowth-inhibitingeffectsonJurkatcells,respectively.TheresultssuggestedthattherIL-16mightbearegulatorforthegrowthorapoptosisofJurkatcellsatadose-dependentmanner.Thegrowth-inhibitingeffectsofrIL-16mightbeFas/FasLindependent,but,associatedwiththeactivationofPKC,up-regulatedexpressionofc-MycandBid,andtheparticipationoftheERKsignalpathwayinJurkatcells.

  • 标签: IL-16 CD4+T细胞 趋化因子 信号传递 生长调节
  • 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