学科分类
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8 个结果
  • 简介:Humantumornecrosisfactorα(hTNFα),apleiotropiccytokinewithactivitiesrangingfromhostdefensemechanismsininfectionandinjurytoseveretoxicityinsepticshockorotherrelateddiseases,isapromisingtargetfordrugscreening.UsingtheSELEX(systematicevolutionofligandsbyexponentialenrichment)process,weisolatedoligonucleotideligands(aptamers)withhighaffinitiesforhTNFα.Aptamerswereselectedfromastartingpoolof40randomizedsequencescomposedofabout1015RNAmolecules.RepresentativeaptamersweretruncatedtotheminimallengthwithhighaffinityforhTNFαandwerefurthermodifiedbyreplacementof2'-OHwith2'-Fand2'-NH2atallribopurinepositions.ThesemodifiedRNAaptamerswereresistanttonuclease.ThespecificityoftheseaptamersforhTNFαwasconfirmed,andtheiractivitytoinhibitthecytotoxicityofhTNFαonmouseL929cellswasdetermined.Resultsdemonstratedthatfour2'-NH2-modifiedaptamersboundtohTNFαwithhighaffinityandblockedthebindingofhTNFαtoitsreceptor,thusprotectingtheL929cellsfromthecytotoxicityofhTNFα.OligonucleotideaptamersdescribedherearepotentialtherapeuticsanddiagnosticsforhTNFc-relateddiseases.

  • 标签: HTNFΑ 人肿瘤坏死因子Α 相似法则 RNA 核糖核酸 低聚核苷酸配位子
  • 简介:Domaindatabaseisessentialfordomainpropertyresearch.Eliminatingredundantinformationindatabasequeryisveryimportantfordatabasequality.Herewereportthemanualconstructionofanon-redundanthumanSH2domaindatabase.Thereare119humanSH2domainsin110SH2-containingproteins.HumanSH2swerealignedwithClustalX,andahomologoustreewasgenerated.Inthistree,proteinswithsimilarknownfunctionwereclassifiedintothesamegroup.Someproteinsinthesamegrouphavebeenreportedtohavesimilarbindingmotifsexperimentally.Thetreemightprovidecluesaboutpossiblefunctionsofhypotheticalproteinsforfurtherexperimentalverification.

  • 标签: 人类基因组计划 SH2域 同源性 系统进化树 非冗余数据库
  • 简介:Werecentlyreportedtheuseofagene-trappingapproachtoisolatecellclonesinwhichareportergenehadintegratedintogenesmodulatedbyT-cellactivation.WehavenowtestedapanelofclonesfromthatreportandidentifiedtheonethatrespondstoavarietyofG-proteincoupledreceptors(GPCR).TheβlactamasetaggedEGR-3JurkatcellwasusedtodissectspecificGPCRsignalinginvivo.ThreeGPCRswerestudied,includingthechemokinereceptorCXCR4(Gicoupled)thatwasendogenouslyexpressed,theplateletactivationfactor(PAF)receptor(Gq-coupled),andβ2adrenergicreceptor(Gs-coupled)thatwasbothstablytransfected.Agonistsforeachreceptoractivatedtranscriptionoftheβ-lactamasetaggedEGR-3gene.InductionofEGR-3throughCXCR4wasblockedbypertussistoxinandPD58059,aspecificinhibitorofMEK(MAPK/ERKkinase).NeitheroftheseinhibitorsblockedisoproterenolorPAF-mediatedactivationofEGR-3.Conversely,β2-andPAF-mediatedEGR-3activationwasblockedbythep38,specificinhibitorSB580.Inaddition,bothβ2-andPAF-mediatedEGR-3activationcouldbesynergisticallyactivatedbyCXCR4activation.ThiscombinedresultindicatesthatEGR-3canbeactivatedthroughdistinctsignaltransductionpathwaysbydifferentGPCRsandthatsignalscanbeintegratedandamplifiedtoefficientlytunethelevelofactivation.

  • 标签: G-蛋白相连受体 信号通道 转移因子 EGR-3
  • 简介:Inourpreviousstudies,DAZAP2geneexpressionwasdown-regulatedinuntreatedpatientsofmultiplemyeloma(MM).ForbetterstudyingthestructureandfunctionofDAZAP2,afull-lengthCdnawasisolatedfrommononuclearcellsofanormalhumanbonemarrow,sequencedanddepositedtoGenbank(AY430097).ThissequencehasanidenticalORF(openreadingframe)astheNM_014764fromhumantestisandtheD31767fromhumancelllineKG-1.PhylogeneticanalysisandstructurepredictionrevealthatDAZAP2homologuesarehighlyconservedthroughoutevolutionandshareapolyprolineregionandseveralpotentialSH2/SH3bindingsites.DAZAP2occursasasingle-copygenewithafour-exonorganization.WefurthernoticedthatthefunctionalDAZAP2geneislocatedonChromosome12anditspseudogenegeneisonChromosome2withelectroniclocationofhumanchromosomeinGenbank,thoughnogeneticabnormalitiesofMMhavebeenreportedonChromosome12.TheORFofhumanDAZAP2encodesa17-kDaprotein,whichishighlysimilartomousePrtb.TheDAZAP2proteinismainlylocalizedincytoplasmwithadiscretepatternofpunctuateddistribution.DAZAP2mayassociatewithcarcinogenesisofMMandparticipateinyet-to-beidentifiedsignalingpathwaystoregulateproliferationanddifferentiationofplasmacells.

  • 标签: 骨髓瘤 聚脯氨酸 DAZAP2 基因 结构 表达