简介：Seventy-fivepreviouslyknownplantmicroRNAs(miRNAs)wereclassifiedinto14familiesaccordingtotheirgenesequenceidentity.Atotalof18,694plantexpressedsequencetags(EST)werefoundintheGenBankESTdatabasesbycomparingallpreviouslyknownArabidopsismiRNAstoGenBank'splantESTdatabaseswithBLASTalgorithms.AfterremovingtheESTsequenceswithhighnumbers(morethan2)ofmismatchednucleotides,atotalof812ESTcontigswereidentified.AfterpredictingandscoringtheRNAsecondarystructureofthe812ESTsequencesusingmFoldsoftware,338newpotentialmiRNAswereidentifiedin60plantspecies,miRNAsarewidespread.SomemicroRNAsmayhighlyconserveintheplantkingdom,andtheymayhavethesameancestorinveryearlyevolution.ThereisnonucleotidesubstitutioninmostmiRNAsamongmanyplantspecies.SomeofthenewidentifiedpotentialmiRNAsmaybeinducedandregulatedbyenvironmentalbioticandabioticstresses.Somemaybepreferentiallyexpressedinspecifictissues,andareregulatedbydevelopmentalswitching.ThesefindingssuggestthatESTanalysisisagoodalternativestrategyforidentifyingnewmiRNAcandidates,theirtargets,andothergenes.AlargenumberofmiRNAsexistindifferentplantspeciesandplayimportantrolesinplantdevelopmentalswitchingandplantresponsestoenvironmentalabioticandbioticstressesaswellassignaltransduction.EnvironmentalstressesanddevelopmentalswitchingmaybethesignalsforsynthesisandregulationofmiRNAsinplants.AmodelformiRNAinductionandexpression,andgeneregulationbymiRNAishypothesized.

简介：Phytohormoneabscisicacid(ABA)wascriticalformanyplantgrowthanddevelopmentalprocessesincludingseedmaturation,germinationandresponsetoenvironmentalfactors.WiththepurposetodetectthepossibleABArelatedsignaltransductionpathways,wetriedtoisolateABA-regulatedgenesthroughcDNAmacroarraytechnologyusingABA-treatedriceseedlingasmaterials(undertreatmentfor2,4,8and12h).Of6144cDNAclonestested,37differentialclonesshowinginductionorsuppressionforatleastonetime,wereisolated.Ofthem30and7wereup-ordown-regulatedrespectively.Sequenceanalysesrevealedthattheputativeencodedproteinswereinvolvedindifferentpossibleprocesses,includingtranscription,metabolismandresistance,photosynthesis,signaltransduction,andseedmaturation.6cDNAcloneswerefoundtoencodeproteinswithunknownfunctions.RegulationbyABAof7selectedclonesrelatingtosignaltransductionormetabolismwasconfirmedbyreversetranscriptionPCR.Inaddition,somecloneswerefurthershowntoberegulatedbyotherplantgrowthregulatorsincludingauxinandbrassinosteroid,which,however,indicatedthecomplicatedinteractionsofplanthormones.PossiblesignaltransductionpathwaysinvolvedinABAwerediscussed.

简介：SomerecentstudiesindicatedthatGABAergicsystemisinvolvedinmammalianspermacrosomereaction(AR),butdirestevidencepertainingtotheexpressionofgatlinmammalianspermisnotyetdemonstrated.Inthisstudy,weevaluatedthepresenceof67kDaGAT1proteinandmRNAinrattestisbyWesternblottingandreversetranscription-polymerasechainreaction.Meanwhile,immunohistochemicalandimmunofluorescentanalysesalsoidentifiedGAT1proteinontheelongatedspermatidandsperm.Theseresultsindicatedthatrattestisisanovelsiteofgatlexpression.FurtherstudiesshouldbetakentoexploretheroleofGAT1proteinonspermacrosomereaction.

简介：以便学习TGF-beta1的结构功能细节，重组体老鼠TGF-beta1的成熟形式在细菌被表示。TGF-beta1(氨基酸279-390)的112氨基酸的carboxyl终端部分的合成被一个可诱导的基因表示系统基于抗菌素T7RNA控制。这个系统允许重组体TGF-beta1的活跃、选择的合成。在减少条件下面在SDS-polyacrylamide胶化上决定的表示TGF-alpha1单体的分子量是大约13kD。连续净化洗与纯化步是足够的净化表示产品到同质的单个胶化过滤结合了。氨基终端的定序表明重组体蛋白质的N终端与出版数据相同。在西方的污点分析，重组体多肽对polyclonalTGF-beta1抗体显示出优秀antigenicity。在这研究表示的成熟重组体老鼠TGF-beta1提供一个有用工具因为未来详细说明了结构、功能的研究。

简介：ErbB2,amemberofthereceptortyrosinekinasefamily,isfrequentlyover-expressedinbreastcancer.ProteolysisoftheextracellulardomainofErbB2resultsinconstitutiveactivationofErbB2kinase.RecentstudyreportedthatErbB2isfoundinthenucleus.Here,weshowedthatErbB2isimportedintothenucleusthroughanuclearlocalizationsignal(NLS)-mediatedmechanism.TheNLSsequenceKRRQQKIRKYTMRR(aa655-668)containsthreeclustersofbasicaminoacidsanditissufficienttotargetGFPintothenucleus.However,mutationinanybasicaminoacidclusterofthisNLSsequencesignificantlyaffectsitsnuclearlocalization.Furthermore,itwasfoundthatthisNLSisessentialforthenuclearlocalizationofErbB2sincetheintracellulardomainofErb2lackingNLScompletelyabrogatesitsnucleartranslocation.Takentogether,ourstudyidentifiedanovelnuclearlocalizationsignalandrevealsanovelmechanismunderlyingErbB2nucleartraffickingandlocalization.

简介：Withtheexceptionofmatureerythrocytes,cellswithinthehumanhematopoieticsystemarecharacterizedbythecellsurfaceexpressionofthepan-leukocytereceptorCD45.Here,weidentifyanovelsubsetamongmononuclearcordbloodcellsdepletedoflineagecommitmentmarkers(Lin-)thataredevoidofCD45expression.Surprisingly,functionalexaminationofLin-CD45-cellsalsolackingcellsurfaceCD34revealedtheywerecapableofmultipotentialhematopoieticprogenitorcapacity.Co-culturewithmouseembryoniclimbbudcellsdemonstratedthatLin-CD45-CD34-cellswerecapableofcontributingtocartilagenodulesanddifferentiatingintohumanchondrocytes.BMP-4,amesodermalfactorknowntopromotechondrogenesis,significantlyaugmentedLin-CD45-CD34-differentiationintochondrocytes.Moreover,unlikeCD34+humanhematopoieticstemcells,Lin-CD45-CD34-cellswereunabletoproliferateorsurviveinliquidcultures,whereassingleLin-CD45-CD34-cellswereabletochimerizetheinnercellmass(ICM)ofmurineblastocystsandproliferateinthisembryonicenvironment.OurstudyidentifiesanovelpopulationofLin-CD45-CD34-cellscapableofcommitmentintobothhematopoieticandchondrocyticlineages,suggestingthathumancordbloodmayprovideamoreubiquitoussourceoftissuewithbroaderdevelopmentalpotentialthanpreviouslyappreciated.

简介：XADisanapoptosisspecificDNaseinXenopusandcancutthelinker-DNAbetweennucleosomesduringapoptosisinXenopuslaeviseggextractinducedbycytochromec.XADismostlikelytobethehomologuetoDFF40inhumans.TheactivityofDFF40canbeinhibitedbyDFF45.WereportmolecularcloningandidentificationofanXADinhibitor,IXAD(inhibitorofXAD),inXenopuseggs.WeclonedthecompletecDNAoftheDFF45homologue,IXAD.ThereisaspecificDEVDsequenceinitsN-terminal,whichserves

简介：ASK1(ARABIDOPSIS象SKP1一样)蛋白质是招募的ubiquitinligase建筑群指向的SCF(Skp1-Cullin-F盒子蛋白质)的一个批评部件为由26Sproteosome的降级的蛋白质。为了调查蛋白质，那被调停ASK1的解朊作用小径在Arabidopsis花影响，我们用二维的电气泳动(2-DE)比较了Arabidopsis野类型和ask1异种花芽的proteomes。有在与野类型花相比的ask1异种花的更高或更低的丰富的十个蛋白质点被切除并且使分析遭到了到进一步集体的spectrometry(MS)。结果证明他们是涉及相片形态发生，生理节奏的摆动，翻译以后的过程，压力反应和房间扩大或延伸的蛋白质，建议那些过程在ask1异种被影响。基因也是的这些的抄本层次基于Affymetrix基因芯片比较了微数组数据。没有重要差别为大多数基因被观察，建议有在ask1异种的累积的提高的层次的蛋白质能是一条调停ASK1的解朊作用小径调整的候选人目标。阐明的这些结果帮助在Arabidopsis发展过程并且也的ASK1的多种的功能表明关于基因功能学习蛋白质层次的重要性和必要性。

简介：ToexplorethemolecularmechanismofchromatinremodelinginvolvedintheregulationoftranscriptionalactivationofspecificgenesbyamyogenicregulatoryfactorMyogenin,weusedNIH3T3fibroblastswithastablyintegratedH1.1-GFPfusionproteintomonitorhistoneH1movementdirectlybyfluorescencerecov-eryafterphotobleaching(FRAP)inlivingcells.TheobservationfromFRAPexperimentswithmyogenintransfectedfibroblastsshowedthattheexchangerateofhistoneH1inchromatinwasobviouslyincreased,indicatingthatforcedexpressionofexogenousMyogenincaninducechromatinremodeling.Thehyper-acetylationofhistonesH3andH4frommyogenintransfectedfibroblastswasdetectedbytriton-acid-urea(TAU)/SDS(2-D)electrophoresisandWesternblotwithspecificantibodiesagainstacetylatedN-terminiofhistonesH3andH4.RT-PCRanalysisindicatedthatthenAChRa-subunitgenewasexpressedinthetrans-fectedfibroblasts.TheseresultssuggestthattheexpressionofexogenousMyogenincaninducechromatinremodelingandactivatethetranscriotionofMvogenin-targetedgeneinnon-musclecells.

简介：Themethodoflasercapturemicrodissection(LCM)combinedwithsuppressivesubtractivehybridization(SSH)wasdevelopedtoisolatespecificgermcellsfromhumantestissectionsandtoidentifythegenesexpressedduringdifferentiationanddevelopment.Inthepresentstudy,over10,000primaryspermatocytesandroundspermatidcellsweresuccessfullyisolatedbyLCM.UsingthecDNAsfromprimaryspermatocytesandroundspermatids,SSHcDNAslibraryofprimaryspermatocyte-specificwasconstructed.TheaverageinsertsizeofthecDNAisolatedfrom75randomlypickedwhitecloneswas500bp,rangingfrom250bpto1.7kb.Usingthedot-blotmethod,atotalof421cloneswereexamined,resultingintheidentificationof390positiveclonesemittingstrongsignals.PartialsequenceofcDNAspreparedfromeachclonewasdeterminedwithanoverallsuccessrateof84.4%.GenesencodingcytochromecoxidaseⅡandtherescuefactor-humaninweremostfrequentlyexpressedinprimaryspermatocytes,suggestingtheirrolesinvolvedinmeiosis.

简介：

简介：Usingtwo-colourflowcytometry＞200antibodiessubmittedtothe8thInternationalWorkshopofHumanLeukocyteDifferentiationAntigens(HLDA8)havebeenanalyzedfortheirreactivitywithrestingandactivatedCD203c+basophils.Fourantibodieseithernon-reactiveorweaklyreactivewithrestingbasophilsexhibitedanincreasedreactivitywithbasophilsactivatedbyanti-IgE-mediatedcross-linkingofthehighaffinityIgEreceptor(FcεRI).TheseincludeantibodiesagainstCD164(WS-80160,cloneN6B6andWS-80162,clone67D2),aswellastworeagentswithpreviouslyunknownspecificitiesthatwereidentifiedasCD13(WS-80274,cloneA8)andCD107a(WS-80280,cloneE63-880).Theactivationpatternsfollowedeitherthe'CD203c-like'or'CD63-like'activationprofile.TheCD203cprofileischaracterizedbyarapidandsignificantupregulation(ofCD13,CD164,andCD203c),reachingmaximumlevelsafter5-15minofstimulation.ThePhosphoinositide-3-kinase(PI3K)-specificinhibitorWortmannininhibitedtheupregulationofthesemarkerswhereas12-O-tetradecanoyl-phorbol-13-acetate(TPA)inducedarapidandFcεRI-independentupregulationwithin1-2min.IntheCD63profile,maximumupregulation(ofCD63andCD107a)wasdetectedonlyafter20-40min,andupregulationbyTPAreachedmaximumlevelsafter60min.Insummary,ourdataidentifyCD13,CD107a,andCD164asnovelbasophil-activationantigens.Basedontimekineticsofupregulation,wehypothesizethatmoleculesofthe'CD203cgroup'andthe'CD63group'arelinkedtotwodifferentmechanismsofbasophilactivation.