学科分类
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13 个结果
  • 简介:组蛋白甲基化是参予细胞过程一个多样数组重要epigenetic现象并且被发现了与癌症被联系。几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JMJD3Transfection引起了整齐乙醇H3K27特定减小,但是没在di-单音甲基H3K27上有效果,或嘘H3K4H3K9上一离氨酸methylations。Theenzymatic活动要求JmjC域被建议了为余因子绑定重要保存组氨酸。试管内生物化学实验证明那JMJD3directly催化demethylation。另外,我们发现JMJD3起来在前列腺癌症,和它表示调整了在变形前列腺癌症是更高。因此,我们作为能够把整齐乙醇组从移开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。

  • 标签: 组蛋白 甲基化物 前列腺癌 临床
  • 简介:流行性感冒所有已知子类型A病毒在野水鸟被维持,这些病毒自然水库。流行性感冒A病毒被孤立从许多有改变病态死亡率动物种类。更重要地,流行性感冒A病毒与潜在地致命结果在人引起呼吸疾病。在人本地或全球爆发被过量住院死亡典型地描绘。在1997,H5N1子类型高度病原流行性感冒病毒在传给人香港出现了,导致由鸟流行性感冒病毒感染的人死亡首先记录盒子。在越南,印度尼西亚,泰国在家禽在2003年7月开始新爆发,高度病原H5N1流行性感冒病毒后来在整个亚洲并且进欧洲非洲传播了。这些病毒继续与高死亡率感染人并且引起隐约可见世界范围担心流行。而且,H5N1病毒爆发在整个亚洲在家禽工业上有破坏效果。因为H5N1病毒爆发看起来从南部中国发源,我们这里在中国检验H5N1流行性感冒病毒,与他们生物性质上一个重音。

  • 标签: 甲型流感病毒 H5N1型 生物学特性 高致病性禽流感 H5N1禽流感病毒 H5N1亚型
  • 简介:Ionizingradiationisoneofthemosteffectivetoolsincancertherapy.Inapreviousstudy,wereportedthatproteintyrosinekinase(PTK)inhibitorsmodulatetheradiationresponsesinthehumanchronicmyelogenousleukemia(CML)celllineK562.Thereceptortyrosinekinaseinhibitor,genistein,delayedradiation-inducedcelldeath,whilenon-receptertyrosinekinaseinhibitor,herbimycinA(HMA)enhancesradiation-inducedapoptosis.Inthisstudy,wefocusedonthemodulationofradiation-inducedcelldeathbygenisteinandperformedPCR-selectsuppressionsubtractivehybridization(SSH)tounderstanditsmolecularmechanism.Weidentifiedhumanthymidinekinase1(TK1),whichiscellcycleregulatorygeneandconfirmedexpressionofTK1mRNAbyNorthernblotanalysis.ExpressionofTK1mRNAandTK1enzymaticactivitywereparallelintheirincreaseanddecrease.TK1isinvolvedinG1-Sphasetransitionofcellcycleprogression.Incellcycleanalysis,weshowedthatradiationinducedG2arrestinK562cellsbutitwasnotabletosustain.However,theadditionofgenisteintoirradiatedcellssustainedaprolongedG2arrestupto120h.Inaddition,theexpressionofcellcycle-relatedproteins,cyclinAandcyclinB1,providedtheevidencesofG1/SprogressionandG2-arrest,andtheirrelationshipwithTK1incellstreatedwithradiationandgenistein.TheseresultssuggestthattheactivationofTK1maybecriticaltomodulatetheradiation-inducedcelldeathandcellcycleprogressioninirradiatedK562cells.

  • 标签: 染料木素 胸腺嘧啶核苷激酶1 活化 辐射 细胞凋亡 K562
  • 简介:heterotrimericguanine核苷酸绑定蛋白质(G蛋白质)被表明了各种各样发信号调停在植物小径。然而,它在发信号phytochromeA(phyA)角色留下逃犯。在这研究,我们发现新调停phyA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)FR-grown幼苗胚轴发生。房间死亡在G变异gpa1被减轻,但是与野类型(WT)比较在G变异agb1加重了,在调停phyA房间死亡小径GPA1AGB1对抗角色陈述语气。进一步调查显示nonphotoconvertibleprotochlorophyllide(Pchlide633)导致FR累积,在暴露上产生反应氧种类(ROS)到WL,为前提FR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,到黑暗成年幼苗H2O2申请导致类似于前提FR房间死亡显型。这表明ROS是为房间死亡一个批评调停人。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应力幼苗敏感。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胚轴前提FR房间死亡phyA。在phyA位于G蛋白质参与下面发信号可能机制在这研究被讨论。

  • 标签: 细胞死亡 植物色素A 鸟嘌呤 胚轴
  • 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:<正>WeandothershavefirmlyestablishedthatsurfaceIgMreceptor(sIgM-R)crosslinkingwithantibodiestotheiheavychain(anti-i)leadstogrowtharrestandapoptosisinaseriesofwellcharacterizedB-celllymphomas.Thisrequiresablationofc-Mycproteinexpressionandtheconcomitantinductionofthecyclin-dependent-kinaseinhibitor,p27Kip1.Thesignalingmechanismsregulatingc-Mycandp27Kip1proteinexpressionarepoorlyunderstood.However,werecentlyestablishedthatsIgM-Rmediateddown-modulationofthePI-3Kpathwaydirectlyaffectedc-Mycandp27Kip1expressionandaccuratelypredictedgrowtharrest

  • 标签: CH12B细胞淋巴瘤 细胞生长阻滞 细胞凋亡 PI-3K通路 信号转导 IgM受体抗体
  • 简介:Kr眉p像像素因素8(KLF8)抄写因素在房间周期前进起一个关键作用,oncogenic转变,对间充质转变侵略上皮。然而,它原子本地化信号(NLS)没被识别。有另外KLFmonopartiteNLS(mNLS)C2H2锌手指(ZF)KLF8份额,哪个被显示了是为一些另外KLFNLS。在这份报告,用指导PCRmutagenesisimmunofluorescent显微镜学,我们显示出mNLSs,任何单个ZF删除,或变化那混乱Zn2+有约束力或联系DNA主题没影响KLF8原子本地化。删除>然而,从C终点1.5ZF引起了KLF8细胞质累积。令人惊讶地,氨基酸(aa)删除151-200区域几乎从原子核消除了KLF8。有PKC禁止者S165A,K171E或K171R变化,或处理导致了部分细胞质累积。Co-immunoprecipitation证明KLF8与importin-交往了,这个相互作用要求了ZF主题。aa1-150或201-261区域删除独自没改变原子本地化。BrdU加入cyclinD1倡导者酶试金作为野类型KLF8证明在原子本地化KLF8异种有缺陷者不能支持DNA合成或cyclinD1倡导者激活。一起拿,这些结果建议KLF8有二NLS,一包围S165K171并且另外是二双人脚踏车ZF,它为KLF8原子本地化和它细胞功能规定是批评

  • 标签: 调控区 核合作 序列 控制 定位 锌指
  • 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.

  • 标签: 感应现象 HLA-G 基因表达 黑色素瘤 肿瘤细胞 OCM-1A
  • 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.

  • 标签: p53蛋白 乳腺癌 细胞增殖 HER-2/NEU PI3K路径 基因表达