简介：<正>WeandothershavefirmlyestablishedthatsurfaceIgMreceptor(sIgM-R)crosslinkingwithantibodiestotheiheavychain(anti-i)leadstogrowtharrestandapoptosisinaseriesofwellcharacterizedB-celllymphomas.Thisrequiresablationofc-Mycproteinexpressionandtheconcomitantinductionofthecyclin-dependent-kinaseinhibitor,p27Kip1.Thesignalingmechanismsregulatingc-Mycandp27Kip1proteinexpressionarepoorlyunderstood.However,werecentlyestablishedthatsIgM-Rmediateddown-modulationofthePI-3Kpathwaydirectlyaffectedc-Mycandp27Kip1expressionandaccuratelypredictedgrowtharrest

简介：MYB蛋白质在真核细胞的有机体起重要作用。在植物，R1R2R3类型MYB蛋白质在房间周期控制工作。然而，R2R3类型MYB蛋白质是否也涉及房间部门过程，仍然保持未知。这里，我们报导那R2R3类型抄写因素基因，AtMYB59，涉及房间周期前进和根生长的规定。AtMYB59蛋白质在洋葱的原子核是局部性的表皮的房间并且transactivation活动。在酵母房间的AtMYB59的表示压制房间增长，和transformants与更长的房间有更多的原子核和更高的aneuploidDNA内容。在AtMYB59的保存领域的变化在酵母细胞生长上废除它的效果。在同步Arabidopsis房间暂停，AtMYB59基因明确地在房间周期前进期间在S阶段被表示。表示和promoter-GUS分析表明AtMYB59基因富有地在根被表示。转基因的植物overexpressingAtMYB59更短的根与野类型的植物(Arabidopsis就职Col-0)相比，并且在在根尖端的有丝分裂的房间的一半附近在中期。相反地，空变异的myb59-1比关口在中期让更长的根和更少有丝分裂的房间，建议那AtMYB59可以由扩大有丝分裂的房间的中期禁止根生长。AtMYB59调整许多下游的基因，包括CYCB1；1基因，可能通过到MYB应答的元素的绑定。这些结果在细胞周期规定和植物根生长为AtMYB59支持一个角色。

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简介：Uponencounteringtheantigen(Ag),theimmunesystemcaneitherdevelopaspecificimmuneresponseofenteraspecificstateofunresponsiveness,tolerance.TheresponseofBcellstotheirspecificAgcanbeactivationandproliferation,leadingtotheimmuneresponse,oranergyandactivation-inducedcelldeath(AICD),leadingtotolerance.AICDinBlymphocytesisahighlyregulatedeventinitiatedbycrosslinkingoftheBcellreceptor(BCR).BCRengagementinitiatesseveralsignalingeventssuchasactivationofPLCγ,Ras,andPI3K,whichgenerallyspeaking,leadtosurvival.However,intheabsenceofsurvivalsignals(CD40orIL-4Rengagement),BCRcrosslinkingcanalsopromoteapoptoticsignaltransductionpathwayssuchasactivationofeffectorcaspases,expressionofpro-apoptoticgenes,andinhibitionofpro-survivalgenes.ThecomplexinterplaybetweensurvivalanddeathsignalsdeterminestheBcellfateand,consequently,theimmuneresponse.

简介：ApoptosisproducedinBcellsthroughFas(APO-1,CD95)triggeringisregulatedbysignalsderivedfromothersurfacereceptors:CD40engagementproducesupregulationofFasexpressionandmarkedsusceptibilitytoFas-inducedcelldeath,whereasantigenreceptorengagement,orIL-4Rengagement,inhibitsFaskillingandinsodoinginducesastateofFas-resistance,eveninotherwisesensitive,CD40-stimulatedtargets.SurfaceimmunoglobulinandIL-4RutilizeatleastpartiallydistinctpathwaystoproduceFas-resistancethatdifferentiallydependonPKCandSTAT6,respectively.Further,surfaceimmunoglobulinsignalingforinducibleFas-resistancebypassesBtk,requiresNF-κB,andentailsnewmacromolecularsynthesis.TerminaleffectorsofBcellFas-resistanceincludetheknownanti-apoptoticgeneproducts,Bcl-XLandFLIP,andanovelanti-apoptoticgenethatencodesFAIM(FasApoptosisInhibitoryMolecule).faimwasidentifiedbydifferentialdisplayandexistsintwoalternativelysplicedforms;faim-Sisbroadlyexpressed,butfaim-Lexpressionistissue-specific.TheFAIMsequenceishighlyevolutionarilyconserved,suggestinganimportantroleforthismoleculethroughoutphylogeny.InducibleresistancetoFaskillingishypothesizedtoprotectforeignantigen-specificBcellsduringpotentiallyhazardousinteractionswithFasL-bearingTcells,whereasautoreactiveBcellsfailtobecomeFas-resistantandaredeletedviaFas-dependentcytotoxicity.InadvertentoraberrantacquisitionofFas-resistancemaypermitautoreactiveBcellstoescapeFasdeletion,andmalignantlymphocytestoimpedeanti-tumorimmunity.

简介：<正>ThesusceptibilityofprimaryBcellstoFas(APO-1,CD95)-mediatedapoptosisisregulatedbysignalsderivedfromadditionalsurfacereceptors.CD40engagementproducesupregulationofFasexpressionandinducesmarkedsensitivitytoFas-inducedcelldeath,whereasBcellantigenreceptor(BCR)engagementinhibitsFaskillingandtherebyproducesFas-resistance,eveninotherwisesusceptible,CD40-stimulatedtargets.BCRsignalingforinducibleFas-resistancedevelopsoveraperiodof12hoursanddependson

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简介：被象染色体冷凝作用，面向双性人的锭子形成，染色体大会离子，分离和胞质分裂那样的一系列紧安排的事件精确通过有丝分裂调整。染色体运动被和位于着丝点以内的一个专业化染色体领域的锭子微导管的相互作用在有丝分裂期间管理。这个专业化区域，叫了kinetochore，是为锭子微导管着丝点的地点协会。除了用作在染色体和锭子微导管之间的一个物理连接，kinetochore通过微导管马达和定位在或在它附近的锭子集会检查点(囊)传感器在chromosomal分离展出一个活跃角色[例如，1]。

简介：Amajorproblemwhichispoorlyunderstoodinthemanagementofbladdercancerislowsensitivitytochemotherapyandhighrecurrenceaftertransurethralresection.Insulin-likegrowthfactor1receptor(IGF-1R)signalingplaysaveryimportantroleinprogression,invasionandmetastasisofbladdercancercells.Inthisstudy,weinvestigatedwhetherIGF-1Rwasinvolvedinthegrowthstimulatingactivityanddrugresistanceofbladdercancercells.Theresultsshowed:ThemRNAsofIGF-1,IGF-2andIGF-1Rwerestronglyexpressedinserum-freeculturedT24cellline,whereasnormalurothelialcellsdidnotexpressthesefactors/receptorsoronlyintracelevels;T24cellrespondedfarbettertogrowthstimulationbyIGF-1thandidnormalurothelialcells;blockageofIGF1Rbyantisenseoligodeoxynucleotide(ODN)significantlyinhibitedthegrowthofT24cellandenhancedsensitivityandapoptosisofT24cellstomitomycin(MMC).TheseresultssuggestedthatblockageofIGF-IRsignalingmightpotentiallycontributetothetreatmentofbladdercancercellswhichareinsensitivetochemotherapy.

简介：囊包含域的蛋白质属于phosphoinositide磷酸酶(PIPPase家庭)的一个最新识别的家庭。尽管有描绘得好的酶的活动，这个哺乳动物的囊领域PIPPase家庭的生物功能仍然保持大部分未知。我们识别了新奇的囊包含域的蛋白质，老鼠Sac3(rSac3)它是广泛地在各种各样的纸巾表示了并且对endoplasmic蜂窝胃局部性，Golgi复杂、再循环的内涵体。rSac3在vitro作为底层与PI(3)P，PI(4)P和PI(3,5)P(2)显示PIPPase活动，并且在囊域的催化核心的一个变化废除它的酶的活动。rSac3的表示起来在刺激的神经生长因素(NGF)期间调整了PC12细胞neuronal区别，并且在这的表示上，蛋白质在PC12细胞支持神经突长出。相反地，由反感觉oligonucleotides的rSac3表示的抑制减少刺激NGF的PC12房间的神经突长出，并且rSac3的活跃地点变化消除它的neurite-outgrowth-promoting活动。这些结果显示rSac3在通过它的PIPPase活动区分神经原支持神经突长出，建议囊领域PIPPase蛋白质可以参予从到血浆膜的endoplasmic蜂窝胃和Golgi建筑群的前面的膜交通国王，并且可以作为neuronal房间生长和区别的这个关键过程的管理者工作。

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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.

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