简介:CT120,anovelmembrane-associatedgeneimplicatedinlungcarcinogenesis,waspreviouslyidentifiedfromchromosome17pl3.3locus,ahotmutationspotinvolvedinhumanmalignancies.Inthepresentstudy,wefurtherdeterminedthatCT120ectopicexpressioncouldpromotecellproliferationactivityofNIH3T3cellsusingMTSassay,andmonitoredthedownstreameffectsofCT120inNIH3T3cellswithAtlasmousecDNAexpressionarrays.Among588knowngenes,133geneswerefoundtobeupregulatedordownregulatedbyCT120.Twomajorsignalingpathwaysinvolvedincellproliferation,cellsurvivalandanti-apoptosiswereoverexpressedandactivatedinresponsetoCT120:OneistheRaf/MEK/ErksignalcascadesandtheotheristhePI3K/Aktsignalcascades,suggestingthatCT120mightcontribute,atleastinpart,totheconstitutivelyactivationofErkandAktinhumanlungcanercells.Inaddition,sometumormetastasisassociatedgenescathepsinB,cathepsinD,cathepsinL,MMP-2/TIMP-2werealsoupregulatedbyCT120,uponwhichCT120mightbeinvolvedintumorinvasivenessandmetastasis.Inaddition,CT120mightplayanimportantroleintumorprogressionthroughmodulatingtheexpressionofsomecandidate“LungTumorProgression”genesincludingB-Raf,Rab-2,BAX,BAG-1,YB-1,andCdc42.
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: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.
简介:热吃惊(HS)表明的在transducing的肌醇1,4,5-trisphosphate(IP(3))的角色在Arabidopsis被检验。整个植物的IP(3)水平在37度C在HS的1min以内增加了。在HS的3min以后,IP(3)水平到达了最大值2.5褶层增加。用有AtHsp18.2promoter-beta-glucuronidase(GUS)的转基因的Arabidopsis植物熔化基因,GUS活动的水平在non-HS和HS温度由将关入笼中的IP(3)的增加是起来调整的并且由phospholipaseC(PLC)禁止者是下面调整的,这被发现{1-[6-((17beta-3-Methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl]-2,5-pyrrolidinedione}(U-73122)。细胞内部免费的钙离子集中([Ca(2+)](i))在表示apoaequorin的暂停有教养的Arabidopsis房间在37度C在HS期间增加了。有U-73122的处理阻止了增加[Ca(2+)](i)到某程度。上面的结果在更高的植物在HS信号transduction为IP(3)的可能的参与提供了主要证据。
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。
简介:与一级的CD8约会主要组织亲和性抗原极大地提高T房间激活,但是这怎么被完成,不是清楚的。我们探讨CD8的调停抗体的结扎是否独自导致在T房间克隆改变的transcriptional的问题,用基因表示的连续分析。尽管它没能导致公开phenotypic变化,我们发现CD8结扎深刻地在T房间克隆改变抄写,在比得上由CD3的调停抗体的结扎导致了那的规模。然而,产生变化的特性与是实质地禁止的CD8结扎的网效果是不同的。我们推测那绑扎的CD8导致弱,T房间受体(TCR)调停了TCR对手的效果暗示的禁止的信号。我们的结果暗示CD8结扎独自不能因为它没能充分导致NFAT依赖的抄写,激活T房间克隆。
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>WeandothershavefirmlyestablishedthatsurfaceIgMreceptor(sIgM-R)crosslinkingwithantibodiestotheiheavychain(anti-i)leadstogrowtharrestandapoptosisinaseriesofwellcharacterizedB-celllymphomas.Thisrequiresablationofc-Mycproteinexpressionandtheconcomitantinductionofthecyclin-dependent-kinaseinhibitor,p27Kip1.Thesignalingmechanismsregulatingc-Mycandp27Kip1proteinexpressionarepoorlyunderstood.However,werecentlyestablishedthatsIgM-Rmediateddown-modulationofthePI-3Kpathwaydirectlyaffectedc-Mycandp27Kip1expressionandaccuratelypredictedgrowtharrest
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.