简介：TounderstandtheDNA-methylationmediatedgenesilencingmechanisms,weanalyzedincellcultureofthepromoterfunctionoftheMAGE-A1gene,whichisfrequentlydemethylatedandover-expressedinhumanhepatocellularcarcinoma.WehaveestablishedthecorrelationoftheDNAmethylationofthepromoterCpGislandwithexpressionstatusofthisgeneinapaneloftheestablishedlivercancercelllines.ThecrucialCpGdinucleotide(s)withintheminimalpromotersubjectedtothecontrolmediatedbyDNAmethylationwithprofoundbiologicalfunctionswasalsodelineated.Furthermore,anovelsequence-specificDNA-proteininteractionatthe-30CpGdinucleotideupstreamofthegenewasfoundhavingavitalparttoplayintheDNAmethylationmediatedtranscriptionsilencingoftheMAGE-A1gene.OurresultswouldnotonlyprovidenewinsightsintotheDNAmethylationmediatedmechanismsovertranscriptionoftheMAGE-A1gene,butalsopavethewayforfurtherdefiningthecross-talkamongDNAmethylation,histonemodificationandchromatinremodelingindetail.

简介：CleavageofchromosomalDNAintooligonucleosomalsizefragmentsisanintegralpartofapoptosis.ElegantbiochemicalworkidentifiedtheDNAfragmentationfactor(DFF)asamajorapoptoticendonucleaseforDNAfragmentationinvitroGeneticstudiesinmicesupporttheimportenceofDFFinDNAfragmentationandpossiblyinapoptosisinvivo.RecentworkalsosuggeststheexistenceofadditionalendonucleasesforDNAdegradation.Understandingtherolesofindividualendonucleasesinapoptosis,andhowtheymightcoordinatetodegradeDNAindifferenttissuesduringnormaldevelopmentandhomeostasis,aswellasinvariousdiseasedstates,willbeamajorresearchfocusinthenearfuture.

简介：<正>Apoptosisisahighlyregulatedphysiologicalprocesscriticalindevelopmentandtissuehomeostasis.Abnormalapoptosiscanleadtodiseaseconditionsincludingneurodegeneration,autoimmunityandcancer.DNAfragmentationisanintegralpartofapoptosisandhaslongbeensuspectedtobeofcriticalimportanceincleaninguppotentiallyantigenicDNAandgeneticmaterialcapableofinducingneoplasmictransformationinneighboringcells.DirectevidenceforthisfunctionofDNAfragmentationhowever,isstilllacking.TheidentificationofaheterodimericDNAfragmentationfactor45and40(DFF45andDFF40,alsocalledICADforInhibitorofCaspaseActivatedDNaseandCADforCaspaseActivatedDNaserespectively)aswellas

简介：Apoptosiscanbetriggeredbyavarietyofstimuliincludingdeathfactors,anti-cancerdrugsandfactor-deprivation.Theseapoptoticcellsareswiftlyphagocytosedbymacrophagestopreventthereleaseofnoxiousorinflammatorymaterialsfromdyingcells.ThemolecularanalysisofFasligand(adeathfactor)-inducedapoptosisindicatedthatacascadeofproteases(caspases)isactivatedduringthisprocess,whicheventuallyactivatesaspecificDNase(caspase-activatedDNase).CADexistsasacomplexwithitsinhibitor(ICAD)inproliferatingcells.Whenthecellsaretriggeredtoapoptosis,caspases,inparticularcaspase3,inthedownstreamofthecaspasecascadecleaveICAD,whichreleasesCADtocauseDNAdegradationinnuclei.

简介：在Saccharomycescerevisiae，必要基因CDC13编码telomeric遗传上并且身体上与Stn1p和Ten1p交往的搁浅单人赛的DNA有约束力的蛋白质，并且为telomere结束保护和telomere长度控制被要求。Ten1由参予telomere长度规定和染色体结束保护的分子的机制留下逃犯。在这个工作，我们用净化的recombinantCdc13p和Ten1p在胶化过滤分析观察了Cdc13p和Ten1p的一个弱相互作用。Ten1p本身展出一项弱DNA有约束力的活动，但是提高telomericTG1鈥吗？Cdc13p的DNA有约束力的能力。Cdc13p是有Ten1p的co-immunoprecipitated。在变异的ten1-55或ten1-66房间，在Ten1p和Cdc13p之间的损害相互作用与telomericDNA导致长得多的telomeres，以及Cdc13p的一个减少的协会。一致地，Ten1-55和Ten1-66异种蛋白质没能刺激telomeric在vitro的Cdc13p的DNA有约束力的活动。这些结果建议Ten1p提高telomericCdc13p到的DNA有约束力的活动否定地调整telomere长度。

简介：Eelfamilyisahugeone,inwhichmanykindsofeelsespeciallysomemigratoryeels,bearstrongresemblancetoeachother,andarethereforedifficulttobeidentified.Inthisstudy29randomprimerswereusedtomakeRAPDanalysisforJapaneseseel(Anguillajaponica),Europeaneel(Anguillaanguilla)andPikeeel(Muraenesoxcinereus).Andtotally299fragmentswerecounted.Sharedorspecificfragmentswerecountedandgeneticsimilarityorgeneticdistancewerecalculated.ThegeneticsimilaritybetweenJapaneseeelandPikeeelis0.68andthegeneticdistancebetweenthemis0.32;thosebetweenEuropeaneelandPikeeelare0.72and0.28respectively,andbetweenJapaneseeelandEuropeaneelare0.74and0.25respectively.Themethodhasbeenshowntobesuitabletomolecularidentificationofeels.Itprovidesanalternativeapproachtodeterminetherelationshipbetweenspecies.

简介：在源于mitochondrial机能障碍的氧化phosphorylation的改变长被假设了涉及tumorigenesis。线粒体最近被显示了在调整规划房间死亡和房间增长起一个重要作用。而且，mitochondrialDNA(mtDNA)变化在各种各样的癌症房间被发现了。然而，在tumorigenesis的这些mtDNA变化的角色仍然保持大部分未知。这评论集中于基本mitochondrial遗传，mtDNA变化和与癌症联系的结果的mitochondrial机能障碍。潜在的分子的机制，调停从mtDNA变化的致病和到tumorigenesis的mitochondrial机能障碍也被讨论。

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简介：Humanpolymorphonuclearleukocytes(PMN)havebeenreportedtocompletelylackofDNA-dependentproteinkinase(DNA-PK)whichiscomposedofKuproteinandthecatalyticsubunitDNA-PKcs,neededfornonhomologousend-joining(NHEJ)ofDNAdouble-strandbreaks.PromyelocyticHL-60cellsexpressavariantformofKuresultinginenhancedradiationsensitivity.ThisraisesthequestioniflowefficiencyofNHEJ,instrumentalforthecellularrepairofoxidativedamage,isanormalcharacteristicofmyeloiddifferentiation.HereweconfirmedthecompletelackofDNAPKinPMNproteinextracts,andtheexpressionofthetruncatedKu86variantforminHL-60.However,thisdegradationofDNA-PKwasshowntobeduetoaDNA-PK-degradingproteaseinPMNandHL-60.Inaddition,byusingaprotease-resistantwholecellassay,bothKu86andDNA-PKcscouldbedemonstratedinPMN,suggestingthepreviouslyreportedabsenceinPMNofDNA-PKtobeanartefact.ThelevelsofKu86andDNA-PKcsweremuchreducedinPMN,ascomparedwiththatofthelymphocytes,whereasHL-60displayedamarkedlyelevatedDNA-PKconcentration.Inconclusion,ourfindingsprovideevidenceofreduced,notdepletedexpressionofDNA-PKduringthematurestagesofmyeloiddifferentiation.

简介：Meiotic前期我是一个长、复杂的阶段。相应再结合是在meiotic前期期间发生在相应染色体之间的一个重要过程我。chiasmata的形成，它一起保持相应染色体直到中期我到后期，我转移，为合适的染色体分离是批评的。最近的研究建议了SPO11蛋白质在产生被认为是相应再结合的起点的双strandedDNA裂缝(DSB)的地点在很多个有机体保存了功能。DSB的这些地点处理要求RecA相当或相同的事物的功能，例如RAD51，DMC1，和其它，由变异的研究建议了；因此，修理这些meioticDSB的失败导致反常chromosomal引申，导致破坏成熟分裂。这些RecA相当或相同的事物的功能上的最近的发现改进了位于meiotic下面的机制的理解相应再结合。

简介：RecognitionofDNAdamageisacriticalstepforDNAdamage-mediatedcellularresponse.XPCisanimportantDNAdamagerecognitionproteininvolvedinnucleotideexcisionrepair(NER).WehavestudiedtheXPCproteinincisplatinDNAdamagingtreatment-mediatedcellularresponse.ComparisonofthemicroarraydatafrombothnormalandXPCdefectivehumanfibroblastsidentified861XPC-responsivegenesinthecisplatintreatment(withminimumfoldchange≥1.5).Thecellcycleandcellproliferation-relatedgenesarethemostaffectedgenesbytheXPCdefectinthetreatment.Manyothercellularfunctiongenes,especiallytheDNArepairandsignaltransduction-relatedgenes,werealsoaffectedbytheXPCdefectinthetreatment.Tovalidatethemicroarraydata,thetranscriptionlevelsofsomemicroarray-identifiedgeneswerealsodeterminedbyanRT-PCRbasedrealtimePCRassay.TherealtimePCRresultsareconsistentwiththemicroarraydataformostofthetestedgenes,indicatingthereliabilityofthemicroarraydata.Tofurthervalidatethemicroarraydata,thecisplatintreatment-mediatedcaspase-3activationwasalsodetermined.TheWesternblothybridizationresultsindicatethattheXPCdefectgreatlyattenuatesthecisplatintreatment-mediatedCaspase-3activation.Weelucidatedtheroleofp53proteinintheXPCproteinDNAdamagerecognition-mediatedsignalingprocess.TheXPCdefectreducesthecisplatintreatment-mediatedp53response.TheseresultssuggestthattheXPCproteinplaysanimportantroleinthecisplatintreatment-mediatedcellularresponse.Itmayalsosuggestapossiblemechanismofcancercelldrugresistance.

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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：Brassinosteroids(BR)被transmembrane受体和戏察觉在植物生长和开发的重要角色，以及响应环境刺激的房间。transmembrane受体BRI1能直接绑在brassinolide(BL)，并且BAK1与BRI1交往提高发信号的调停BRI1的BR。我们的以前的研究显示了那膜类固醇绑定蛋白质(MSBP1)1能在vitro绑在BL并且否定地涉及BR发信号。进一步阐明内在的机制，我们这里证明MSBP1明确地以一种BL独立的方式在vivo与BAK1的细胞外的领域交往。由MSBP1的增加的表示的压制的房间扩大和BR回答能被overexpressingBAK1或它的细胞内部的kinase领域恢复，建议MSBP1可以压制通过与BAK1交往发信号的BR。Subcellular本地化研究表明MSBP1和BAK1对血浆膜和endocytic泡局部性，MSBP1加速BAK1endocytosis，它导致由向内涵体转移BAK1的平衡发信号的压制的BR。确实，提高了MSBP1表示还原剂在在vivo的BRI1和BAK1之间的相互作用，表明那MSBP1在发信号的BR的早步充当一个否定因素小径。

简介：Changesinthedistributionof1P1-antigeninthedevelopingchickretinahavebeenexaminedbyindriectimmunofluorescencestainingtechniqueusingthenovelmonoclonalantibody(MAb)1P1.Expressionofthe1P1antigenwasfoundtoberegulatedinradialaswellasintangentialdimensionoftheretina,beingpreferentiallyorexclusivelylocatedintheinnerandouterplexiformlayersoftheneuralretinadependingonthestagesofdevelopment,Withtheonsetoftheformationoftheinnerplexiformlayer1P1antigenbecomesexpressedintheretina.Withprogressingdifferentiationoftheinnerplexiformlayer1P1immunofluorescencerevealed2subbandsatE9and6subandsatE18,Atpostnatalstages(afterP3)immunoreactivitywasreducedinaninside-outsidesequenceleadingtothecompleteabsenceofthe1P1antigeninadulthood.1P1antigenexpressionintheouterplexiformlayerwasalsosubjecttodevelopmentalregulation.Thespation-temporalpatternof1P1antigenexpressionwascorrelatedwiththetimecourseofhistologicaldifferentationofchickretina,namelythesynapserichplexiformlayers.Whetherthe1P1antigenwasfunctionallyinvolvedindendriteextensionandsynapseformationwasdiscussed.

简介：Arabidopsisthaliana嘘一deacetylase1(AtHD1或AtHDA19)，酵母RPD3的一个相当或相同的事物，是在植物的许多生理、发展的过程的一个全球管理者。尽管有为在植物基因规定和开发的AtHD1的一个角色的基因证据，AtHD1的生物化学、细胞的性质糟糕被理解。这里，我们在vivo报导AtHD1的细胞的本地化模式并且嘘在vitro的一项deacetylase活动。绿荧光灯的蛋白质(GFP)的短暂、稳定的表示在洋葱房间标注了AtHD1并且分别地，在转基因的Arabidopsis的根，种子和叶子表明AtHD1在euchromatic区域大概在原子核是局部性的并且从核排除。AtHD1的本地化模式与涉及核形成和transgenes的silencing并且分别地重复了DNA元素的AtHD2和AtHDA6的那些不同。另外，一hist一deacetylase活动试金证明在细菌生产的recombinantAtHD1示威了一特定嘘在vitro的一项deacetylase活动。数据建议AtHD1是原子蛋白质并且拥有嘘为对植物生长和开发重要的全球transcriptional规定负责的一项deacetylase活动。

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简介：TheyeastHAL1genewasintroducedintoArabidopsisthalianabyAgrobacteriumtumefaciens-mediatedtransformationwithvacuuminfiltrationunderthecontrolofCaMV35Spromoter.Thirty-threeindividualkanamycinresistantplantswereobtainedfrom75,000seeds.SouthernblottinganalysisindicatedthatHAL1genehadbeenintegratedintoallofthetransgenicplants'genomes.ThecopynumberofHAL1geneintransgenicplantswasmostly1to3bySouthernanalysis.Phenotypesoftransgenicplantshavenodifferenceswithwildtypeplants.Severalsamplesoftransformantswereself-pollinated,andprogeniesfromtransformedandnon-transformedplants(controls)wereevaluatedforsalttoleranceandgeneexpression.MeasurementofconcentrationsofintracellularK+andNa+showedthattransgeniclineswereabletoretainlessNa+thanthatofthecontrolundersaltstress.ResultsfromdifferenttestsindicatedtheexpressionofHAL1genepromotesahigherlevelofsalttoleranceinvivointhetransgenicArabidopsisplants.