简介:heterotrimericguanine核苷酸绑定蛋白质(G蛋白质)被表明了各种各样的发信号调停在植物的小径。然而,它在发信号的phytochromeA(phyA)的角色留下逃犯。在这研究,我们发现新调停phyA的显型指明了far-red照耀(FR)preconditioned房间死亡,它仅仅在跟随暴露到白光(WL)的FR-grown幼苗的胚轴发生。房间死亡在G变异的gpa1被减轻,但是与野类型(WT)比较在G变异的agb1加重了,在调停phyA的房间死亡小径的GPA1和AGB1的对抗角色的陈述语气。进一步的调查显示nonphotoconvertibleprotochlorophyllide(Pchlide633)的导致FR的累积,在暴露上产生反应的氧种类(ROS)到WL,为前提FR的房间死亡被要求。而且,ROS主要在叶绿体被检测用荧光灯探查。有趣地,到黑暗成年的幼苗的H2O2的申请导致类似于前提FR的房间死亡的显型。这表明ROS是为房间死亡的一个批评调停人。另外,我们观察到agb1比WT幼苗对H2O2更敏感,显示G蛋白质可以也修改到ROS应力的幼苗的敏感。一起拿这些结果,我们推断G蛋白质可以涉及表明小径调整Arabidopsis胚轴的前提FR的房间死亡的phyA。在phyA位于G蛋白质的参与下面发信号的可能的机制在这研究被讨论。
简介:Glucosetransporter4(GLUT4)isresponsibleforinsulin-stimulatedglucosetransportingintotheinsulin-sensitivefatandmusclecells.ThedynamicsofGLUT4storagevesicles(GSVs)remainstobeexploredanditisunclearhowGSVsarearrangedbasedontheirmobility.Weexaminedthisissuein3T3-L1cellsviainvestigatingthethree-dimensionalmobilityofsingleGSVlabeledwithEGFP-fusedGLUT4.Athinlayerofcytosolrightadjacenttotheplasmamembranewasilluminatedandsuccessivelyimagedat5Hzunderatotalinternalreflectionfluorescencemicroscopewithapenetrationdepthof136nm.Employingsingleparticletracking,thethree-dimensionalsubpixeldisplacementofsingleGSVwastrackedataspatialprecisionof22nm.Boththemeansquaredisplacementandthediffusioncoefficientwerecalculatedforeachvesicle.Trackingresultsrevealedthatvesiclesmovedasifrestrictedwithinacagethathasameanradiusof160nm,suggestingthepresenceofsomeintracellulartetheringmatrix.ByconstructingthehistogramofthediffusioncoefficientsofGSVs,weobservedasmoothdistributioninsteadoftheexistenceofdistinctgroups.TheresultindicatesthatGSVsaredynamicallyretainedinacontinuousandwiderangeofmobilityratherthanintoseparateclasses.
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:Glatiramer醋酸盐(GA)是过去常对待多重硬化的immunomodulatory肽药。它的处理效果被扩展了到象uveoretinitis,煽动性的肠疾病,接枝拒绝和肝的纤维变性那样的另外的自体免疫的条件。这里,我们报导GA在在cyclophosphamide(CY)改变糖尿病的临床的功课是有效的加强的非肥胖的糖尿病患者(CY点头)老鼠。有显著地减少的GA的治疗在老鼠和改善insulitis的糖尿病的率,它与增加的CD4+CD25+Foxp3+T房间反应与一致在对待老鼠。GA处理导致了抄写因素Foxp3的增加的表示并且在vivo并且在vitro提高了interleukin-4(IL-4)的生产。Foxp3的起来规定上的GA的效果通过IL-4部分被调停,是明显的。IL-4被发现维持Foxp3表示和CD4+CD25+规章的T房间(Tregs)的规章的功能。这研究提供GA通过Tregs的正式就职为类型1糖尿病有处理潜力,那增加的IL-4生产为提高的Treg在GA处理的功能部分负责的新证据。
简介:组蛋白甲基化是参予细胞的过程的一个多样的数组的重要epigenetic现象并且被发现了与癌症被联系。几的Recentidentification嘘一demethylases证明了那嘘一甲基化是一个可逆过程。通过一条候选人途径,我们化学上有简历作为H3K27demethylase识别了JMJD3。进HeLa房间的JMJD3的Transfection引起了整齐的乙醇H3K27的特定的减小,但是没在di-和单音的甲基H3K27上有效果,或嘘H3K4和H3K9上的一离氨酸methylations。Theenzymatic活动要求JmjC域和被建议了为余因子绑定重要的保存组氨酸。试管内生物化学的实验证明那JMJD3directly催化demethylation。另外,我们发现JMJD3起来在前列腺癌症,和它的表示调整了在变形前列腺癌症是更高的。因此,我们作为能够把整齐的乙醇组从移开的ademethylase识别了JMJD3嘘一H3离氨酸27并且起来在前列腺癌症调整了。
简介:混合的系kinase(MLK3)3是被肿瘤坏死因素激活的激活mitogen的蛋白质kinasekinasekinase--伪(TNF-伪)并且明确地在TNF-伪刺激上激活c6月N终端kinase(JNK)。TNF-伪由激活MLK3的机制不被知道。TNF联系受体的因素(TRAF)是被招募到TNF受体的细胞质的结束并且调停的改编者分子,包括JNK的激活下游的发信号。这里,我们报导MLK3与TRAF2,TRAF5和TRAF6联系;然而,仅仅TRAF2能显著地导致MLK3的kinase活动。到TRAF领域并且为到它的C终端一半(氨基酸511-847)的MLK3的TRAF2地图的相互作用领域。与对方一起的内长的TRAF2和响应以一种时间依赖者方式的TNF-伪处理的MLK3伙伴。在MLK3和TRAF2之间的协会调停有绑在MLK3的TRAF2删除异种的MLK3激活和竞争以一种剂量依赖者方式稀释MLK3kinase活动,在TNF-伪处理上。而且MLK3的下游的目标,JNK被TNF-伪以一种TRAF2依赖的方式激活。因此,我们在TRAF2和MLK3之间的直接相互作用为TNF-伪-被要求的数据表演导致了MLK3和它的下游的目标的激活,JNK。
简介:Mammaliancelltotipotencyisasubjectthathasfascinatedscientistsforgenerations.AlonglastingquestionwhethersomeofthesomaticcellsretainstotipotencywasansweredbythecloningofDollyattheendofthe20thcentury.Thedawnofthe218thasbroughtforwardgreatexpectationsinharnessingthepoweroftotipotentcyinmedicine.Throughstemcellbiology,itispossibletogenerateanypartsofthehumanbodybystemcellengineering.Considerableresourceswillbedevotedtoharnesstheuntappedpotentialsofstemcellsintheforeseeablefuturewhichmaytransformmedicineasweknowtoday.Atthemolecularlevel,totipotencyhasbeenlinkedtoasingulartranscriptionfactoranditsexpressionappearstodefinewhetheracellshouldbetotipotent.NamedOct4,itcanactivateorrepresstheexpressionofvariousgenes.Curiously,verylittleisknownaboutOct4beyonditsabilitytoregulategeneexpression.ThemechanismbywhichOct4specifiestotipotencyremainsentirelyunresolved.Inthisreview,wesummarizerethestructureandfunctionofOct4andaddresstoOct4functioninmaintainingtotipotencyorpluripotencyofembryonicstemcels.
简介:在胸腺的中央忍耐是为删除汽车的主要机制反应T房间。尽管有这,进圆周的自我反应的T淋巴细胞的逃跑揭示汽车免疫的威胁。补偿它的瑕疵,胸腺也与镇压功能生产Foxp3+CD4+CD25+规章的T房间的一个自然地发生的子集,能够控制汽车反应房间。Foxp3(叉头框P3),为房间的这个子集的系特定的标记,对他们的thymic开发和外部功能关键,并且还Foxp3驾驶的transcriptional程序直到现在大部分未定义。新兴的证据提供了卓见进它的角色:从Foxp3到的能力与象NFAT那样的另外的抄写因素合作,到目标的染色体宽的描述,基因直接由Foxp3跳了并且调整。这里,我们讨论自然地发生的规章的T房间的发现-他们的显型,发展,维护,和功能-大部分当他们被系特定的标记定义,Foxp3。
简介:<正>Asoneofthemostcharacterizedcytokines,interleukin3(IL-3)iswellknownforitssurvivaleffectonbothprogenitorsandmaturebloodcells.Althoughwiththeextensivestudies,thesignalingpathwaysandunderlyingmechanismleadingtosurvivalresponsesofIL-3stillarenotcompletelyunderstood.Recently,anapoptoticgeneticpathwayofC.eleganswassuggestedtobeevolutionallyconservedinthatcontrolsthecytokine-dependentanti-apoptoticresponsesinmammalianhematopoieticcelllineages.Amongthispathway,Ces-2isknowntobethefirstdeathspecificationgeneintheC.eleganspathwayandencodesabZIPfamilytranscriptionalfactorthatsharesthesameDNArecognitionsequencewithanoncoprotein,
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: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:InteractionbetweencytotoxicTlymphocyte-associatedantigen-4(CTLA4,CD152)andB7molecules(B7-1andB7-2)isofimportanceinthecellulareventsoflymphocyte,includingantigen-specificT-cellactivationandinductionofautoreactiveT-cell.WedescribehaerethefirstintroductionofamurinesolubleCTLA4gene,CTLA4Ig,toMm1cells,amacrophagiccellline.CTLA4IgwassuccessfullyexpressedonMm1cellsandtheexpressedCTLA4IgwasfoundtobefunctionallyactiveintheirbindingtoB7moleculesbyflowcytometryandimmunofluorescencestudies.ThebiologicalactivityofCTLA4IgfromthetransfectedMm1cellswasstudiedandshowedinhibitoryactivityonmixedlymphocyteculture.AhighCTLA4Igproducingmacrophagiccelllinewasobtained.AsMm1cellswereregardedasdifficultforgenetransfectionandtherehassofarbeennoreportonexpressionofCTLA4IggeneonMm1cells,theseresultssuggestedthattheCELA4IgexpressingMm1cellscouldbeusefulforanalysisofCTLA4andB8moleculeinteractioninbothmacrophageandT-cell.
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.
简介:Asimplemethodtocreateachromosome-specificDNAlibrqaryofrice,includingmicrodissection,amplification,charterizationandcloning,isdescribed.Ricechromosome4fromametaphasecellhasbeenisolatedandamplifiedbytheLinkerAdapterPCR(LA-PCR).ThePCRproductswerelabeledasprobeswithDIG-11-dUTPusingtherandomprimingmethod.SouthernblotanalysiswithricegenomicDNAandspecificRFLPmarkersdemonstratedthatthePCRproductswerederivedfromricechromosome4.Alargelibrarycomprisingover100,000recombinantplasmidmicroclonesfromricechromosome4wasconstructed.Colonyhybridizationshowedthat58%oftheclonescontainedsingleorlow-copysequencesand42%containedrepetitivesequences.ThesizeofinsertsgeneratedbyPCRrangedfrom140bpto500bp.ThismethodwillfacilitatecloningofthespecificchromosomeDNAmarkersandimportantgenesofrice.
简介:Galα(1,3)Gal(galepitope)isacarbohydrateepitopeandsynthesizedinlargeamountbyα(1,3)galactosyltransferase[α(1,3)GT]enzymeonthecellsoflowermammaliananimalssuchaspigsandmice.Humanhasnogalepitopeduetotheinactivationofα(1,3)GTgenebutproducesalargeamountofantibodies(anti-Gal)whichrecognizeGalα(1,3)Galstructuresspecifically.Inthisstudy,areplicationdeficientrecombinantadenoviralvectorAd5sGTcontainingpigα(1,3)GTcDNAwasconstructedandcharacterized.Adenoviralvector-mediatedtransferofpigα(1,3)GTgeneintohumantumorcellssuchasmalignantmelanomaA375,stomachcancerSGC-7901,andlungcancerSPC-A-1wasreportedforthefirsttime.ResultsshowedthatGalepitopedidnotincreasethesensitivityofhumantumorcellstohumancomplement-mediatedlysis,althoughhumancomplementactivationandthebindingofhumanIgGandIgMnaturalantibodiestohumantumorcellswereenhancedsignificantlyafterAd5sGTtransduction.AppearanceofgalepitopeonthehumantumorcellschangedtheexpressionofcellsurfacecarbohydratesreactingwithUlexeuropaeusI(UEAI)lectins,Viciavillosaagglutinin(VVA),Arachishypogaeaagglutinin(PNA),andGlycinemaxagglutinin(SBA)todifferentdegrees.Inaddition,noeffectofgalepitopeonthegrowthinvitroofhumantumorcellswasobservedinMTTassay.