简介：在干细胞生物学要处理的一个关键问题是控制胚胎的茎(ES)的分子的发信号机制细胞pluripotency。干细胞性质被象脱氧核糖核酸甲基化并且染色质改变那样的特定的抄写因素和epigenetic过程支配。几个cytokines/growth因素作为批评ES房间管理者被识别了。然而，在我们在ES房间连接细胞外的信号到transcriptional规定的细胞内部的发信号小径的知识有差距。这短评论讨论Shp2的生理的角色，细胞质的酷氨酸磷酸酶，在管理EScell自强对区别的分子的开关中。Shp2支持ES细胞分化，英皇家空军之阶级最低之兵的主要throughbi方向性的调整和Stat3小径。在老鼠ES房间的Shp2的删除导致更有效的自强。这观察提供动力在文化为ES房间的维护和扩大开发Shp2禁止者。

简介：(QS)在治安法官察觉到处理，细菌由利用响应许多环境暗示称为autoinducers的小发信号的分子调整基因表示。Autoinducer2(AI-2)，表明分子的QS建议涉及interspecies通讯，被克否定、克积极的细菌的许多种类生产。在Escherichiacoli和沙门氏菌typhimurium，细胞外的AI-2被lsr操纵子编码的transporter进口进房间。lsr操纵子在上游，有编码LsrR的分叉地抄录的基因，它以前被报导镇压lsr操纵子和自己的抄写。这里，我们第一次证明了LsrR镇压lsr操纵子和自己由的抄写对他们用胶化移动和DNase的倡导者直接有约束力我footprinting试金。牛乳糖记者试金进一步建议在lsrR和lsrA倡导者区域的二个主题为LsrR绑定是关键的。而且，与结论一致，那phosphorylatedAI-2能在以前的研究减轻LsrR的压抑，我们phospho-AI-2显示的数据表演不能在vitro绑在它的自己的倡导者的LsrR。

简介：(FRS2)成纤维细胞生长因素(FGF)受体底层2是在FGF小径发信号的主要调停人。最近的研究在FRS2显示出那激活mitogen的蛋白质kinase(MAPK)phosphorylates丝氨酸和threonine残余，否定地影响FRS2的导致FGF的酷氨酸phosphorylation(PY)。几种刺激能导致FRS2的serine/threoninephosphorylation(PS/T)，显示FRS2可能为学习在表明小径的生长因素之间的串音是有用的。这里，我们报导FRS2的导致FGF的PY能被EGF合作刺激在PC12房间稀释；这禁止的效果能被U0126完全颠倒，MEK的一个禁止者。我们进一步在FRS2识别了ERK1/2-binding主题并且在FGF或EGF刺激之上产生了FRS2-3KL，变异的缺乏MAPK绑定和磅。不同野类型(WT)FRS2，FRS2-3KL的导致FGF的PY不能被EGF合作刺激，和更展出的FRS2-3KL-expressingPC12房间禁止响应FGF处理比FRS2-WT-expressing房间区分潜力。这些结果建议FRS2的PS/T由FRS2-MAPK否定规章的循环调停了可以作为从另外的小径把否定规章的信号集成到产生FGFR的信号transduction的一个分子的开关工作。

简介：MembersofBcl-2familyofproteinsareregulatorsofcelldeaththatcanbegroupedintosubfamiliesofprosurvivalandproapoptoticmolecules.Theyarecharacterizedbythepresenceofseveralconservedmotifs,knownastheBcl-2homology(BH)domains,designatedBH1,BH2,BH3andBH4.MutagenesisandstructuralstudiesrevealedthattheBHdomainsareimportantfunctionaldomainsthatarealsorequiredfordimerizationfunction.Recently,asubfamilyofproapoptoticmoleculesonlycontainsBH3motifhasbeenidentifiedsuggestingBH3domainalonemaybesufficientformediatingproapoptoticfunctionamong

简介：Thec-erbB-2proto-oncogeneencodesa185kDaproteinp185,whichbelongstoepidermalgrowthfactorreceptorfamily.Amplificationofthisgenehasbeenshowntocorrelatewithpoorclinicalprognosisforcertaincancerpatients.ThemonoclonalantibodyA21whichdirectedagainstp185specificallyinhibitsproliferationoftumorcellsoverexpressingp185,henceallowsittobeacandidatefortargetedtherapy.InordertoovercomeseveraldrawbacksofmurineMAb,wecloneditsVHandVLgenesandconstructedthesingle-chainFv(scFv)throughapeptidelinker.TherecombinantscFvA21wasexpressedinEscherichiacoliandpurifiedbytheaffinitycolumn.SubsequentlyitwascharacterizedbyELISA,Westernblot,cellimmunohistochemistryandFACS.Alltheseassaysshowedthebindingactivitytoextracellulardomain(ECD)ofp185.BasedonthosepropertiesofscFvA21,wefurtherconstructedthescFv-Fcfusionmoleculewithahomodimerformandtherecombinantproductwasexpressedinmammaliancells.Inaseriesofsubsequentanalysisthisfusionproteinshowedidenticalantigenbindingsiteandactivitywiththeparentantibody.Theseanti-p185engineeredantibodieshavepromisedtobefurthermodifiedasatumortargetingdrugs,withaviewofapplicationinthediagnosisandtreatmentofhumanbreastcancer.

简介：Twomajorapoptosispathwayshavebeendefinedinmammaliancells,theFas/TNF-R1deathreceptorpathwayandthemitochondriapathway.TheBcl-2familyproteinsconsistofbothanti-apoptosisandpro-apoptosismembersthatregulateapoptosis,mainlybycontrollingthereleaseofcytochromecandothermitochondrialapoptoticevents.However,deathsignalsmediatedbyFas/TNF-R1receptorscanusuallyactivatecaspasesdirectly,bypassingtheneedformitochondriaandescapingtheregulationbyBcl-2familyproteins.Bidisanovelpro-apoptosisBcl-2familyproteinthatisactivatedbycaspase8inresponsetoFas/TNF-R1deathreceptorsignals.ActivatedBidistranslocatedtomitochondriaandinducescytochromecrelease,whichinturnactivatesdownstreamcaspases.Suchaconnectionbetweenthetwoapoptosispathwayscouldbeimportantforinductionofapoptosisincertaintypesofcellsandresponsibleforthepathogenesisofanumberofhumandiseases.

简介：

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。

简介：小道，肿瘤坏死因素相关的导致apoptosisligand，是一个新奇有势力通过房间表面死亡受体Trail-R1和Trail-R2的激活的房间死亡小径的内长的使活跃之物。它的角色象在导致激活的房间死亡(AICD)的FasL一样，在免疫系统被表明了。然而，小道的机制导致了apoptosis遗体不清楚。在这份报告，重组体小道蛋白质被表示并且净化。导致apoptosis活动和JurkatT房间上的重组体小道的规定机制是探索试管内。Trypan蓝排除试金证明重组体小道蛋白质活跃地以一种剂量依赖者方式杀死了JurkatT房间。在JurkatT房间的导致小道的apoptosis被Bcl-2显著地在Bcl-2基因transfected房间在表示上减少。有PMA(phorbol12十四酸盐13醋酸盐)的处理，PKC使活跃之物，在JurkatT房间的压制的导致小道的apoptosis。由PMA的apoptosis的抑制被预告的处理与二度废除，一个PKC禁止者。总起来说，Bcl-2在表示上和PMA激活PKC，这被建议活跃地下面调整在JurkatT的调停小道的apoptosis房间。

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：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。

简介：<正>Uponactivation,naiveT-helpercellscandifferentiateintotwomajordistinctsubsets,Thelper1(Th1)andThelper2(Th2),asdefinedbytheireffectorfunctionsandcytokinesecretionpatterns.CytokinemilieuandcostimulatorymoleculeshavebeenshowntoplayanessentialroleindeterminingThelperdifferentiation.However,itisstillunclearhowtheeffectsofsignalsofco-stimulatorymoleculesandcytokinesareexertedduringThelperdifferentiation.Weshowevidencesuggestingthatwhilecytokinesignalsinitiatedifferentiationprogram,theselectiveactionofdeatheffectorsdeterminestheendpointbalanceofdifferenti-

简介：新鲜的水息肉水螅属于门Cnidaria，它在bilaterians的外观前从后生动物的系分叉。以便在metazoans理解apoptosis的进化，我们开始阐明了在这个模型有机体的分子的细胞死亡机械。基于EST和整个水螅染色体集会，我们识别了15caspases。我们证明一个人在apoptosis期间被激活，四与N终端DED，卡片或DD领域有开始者caspases的特征，二在vitro经历autoprocessing。另外，我们描述七Bcl-2-like和二象Bak一样蛋白质。为大多数Bcl-2家庭蛋白质，我们观察了mitochondrial本地化。当在哺乳动物的房间表示了时，象HyBak一样1和2强烈导致的apoptosis。禁止的apoptosis与显示出特别强壮的保护的效果的HyBcl-2-like4在哺乳动物的房间由camptothecin劝诱了的六个Bcl-2家庭成员。这蛋白质也与象HyBak一样交往了1在酵母二混血儿的试金。在它的BH3领域的保存白氨酸的变化两个都与象HyBak一样废除了相互作用1并且anti-apoptotic效果。而且，我们BH-3-only描述新奇水螅蛋白质。这些之一与Bcl-2-like4交往了并且在哺乳动物的房间导致了apoptosis。我们的数据显示为房间死亡规定的一个复杂网络的进化在多细胞的组织的最早、最简单的水平产生了，它在此展出了一复杂性实质地高级比在protostome模型有机体Caenorhabditis和果蝇。

简介：Plasmamembrane(PM)Ca^2+-ATPaseactivityinpoplarapicalbudmeristematiccellsduringshort-day(SD)-induceddormancydevelopmentwasexaminedbyaceriumprecipitationEM-cytochemicalmethod.Ca^2+-ATPaseactivity,indicatedbythestatusofceriumphosphateprecipitatedgrains,waslocalizedmainlyontheinteriorface(cytoplasmicside)ofthePMwhenplantsweregrownunderlongdaysandreachedadeepdormancy.Afewreactionproductswerealsoobservedonthenuclearenvelope.Whenplantbudsweredevelopingdormancyafter28to42dofSDexposure,almostnoreactionproductswerepresentontheinteriorfaceofthePM.Incontrast,alargenumberofceriumphosphateprecipitatedgrainsweredistributedontheexteriorfaceofthePM.After70dofSDexposure,whenbudshaddevelopedadeepdormancy,thereactionproductsofCa^2+-ATPaseactivityagainappearedontheinteriorfaceofthePM.TheresultsseemedsuggestingthattwokindsofCa^2+-ATPasesmaybepresentonthePMduringtheSD-induceddormancyinpoplar.OneistheCa^2+-pumpingATPase,whichislocatedontheinteriorfaceofthePM,formaintainingandrestoringtheCa^2+homeostasis.Theothermightbeandecto-Ca^2+-ATPase,whichislocatedontheexteriorfaceofthePM,fortheexocytosisofcellwallmaterialsassuggestedbythefactofthecellwallthickeningduringthedormancydevelopmentinpoplar.

简介：

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。

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.

简介：

简介：Amurinemacrophage-likecellline,J774,acquried,inresponsetoLPS,anabilitytokilltumornecrosisfactor（TNF）-insensitivetargetP815mastocytomacells,whereasanothercellline,P388D1,didnot.LPS-triggeredsignalingmechanismsbetweenthetwocelllineswerecomparedwithanaimtoinquireaboutthepossiblenatureoftheabove-mentioneddifference.TheresultsshowedthattwocelllinesrespondtoLPS-treatmentbyparallelactivationofbothphospholipasesCandA2（PLCandPLA2）toapproximatelythesameextent.ThemaximumresponseofbothenzymesofJ774cellswasnotedwithin10minofthetreatment,whereasthatofP388D1cellsrequiredmorethan20min.TheotherpropertiesofLPS-responsiveenzymesstudiedweresimilarbetweentwocelllines,ineludingActivationofPLCandPLA2andPKCinmacrophagesbyLPSCa2+augmentationofenzymeactivation,participationofguaninenucleotidebinding（G）proteinsintheinitialactivationprocesses,andinhibitionofenzymeactivationbythepriortreatmentofcellswithcholeraorpartussistoxinsetc.Moreover,LPS-triggeredactivationofPLCandPLA2wasfoundtobefollowedbytheincreaseofPKCactivitiesinbothcelllines.Inspiteofthesesimilarities,J774cellspossessedbothbasicandacidicformsofPKCactivities,whileP388D1cellsownedonlyPKCofbasicform.Nevertheless,thequestionwhyJ774cells,butnotP388D1cells,canacquirethetumoricidalactiyity,aganistP815cellsfollowingLPS-treatmentremainstobeanswered.

简介：OverexpressionandactivationofHER-2/neu(alsoknownasc-erbB-2),aproto-oncogene,wasfoundinabout30%ofhumanbreastcancers,promotingcancergrowthandmakingcancercellsresistanttochemo-andradio-therapy.Wild-typep53iscrucialinregulatingcellgrowthandapoptosisandisfoundtobemutatedordeletedin60-70%ofhumancancers.Andsomecancerswithawild-typep53donothavenormalp53function,suggestingthatitisimplicatedinacomplexprocessregulatedbymanyfactors.Inthepresentstudy,weshowedthattheoverexpressionofHER-2/neucoulddecreasetheamountofwild-typep53proteinviaactivatingPI3Kpathway,aswellasinducingMDM2nucleartranslocationinMCF7humanbreastcancercells.BlockageofPI3KpathwaywithitsspecificinhibitorLY294002causedG1-Sphasearrest,decreasedcellgrowthrateandincreasedchemo-andradio-therapeuticsensitivityinMCF7cellsexpressingwild-typep53.However,itdidnotincreasethesensitivitytoadriamycininMDA-MB-453breastcancercellscontainingmutantp53.OurstudyindicatesthatblockingPI3KpathwayactivationmediatedbyHER-2/neuoverexpressionmaybeusefulinthetreatmentofbreasttumorswithHER-2/neuoverexpressionandwild-typep53.