DNA半保留复制和半不连续复制的提出与确立

doi:10.3969/j.issn02539608.2010.04.008DNA向义和,,100084DNA:DNA;MeselsonStahl;,DNADNA,DNA1953DNA,DNADNA,DNA5,MeselsonStahl,,1968DNADNADNA53,,,,11.1(J.D.Watson)(F.H.C.Crick)!∀DNA1953530,!∀#∃[1],DNA,DNA:DNA(HPO4)5,15,(H3PO4)C3(OH)C5,1,(adenine),(guanine),(thymine)(cytosine),A,G,T,C,,DNA5,353DNADNA,2,,1DNA%229%自然杂志第32卷第4期2DNA,,3,,,DNADNA,DNA53353(A)(T),(G)(C)#∃:#,,,,,,,∃DNA?DNA,:,,,DNA,[2](4)DNADNA,DNA,,DNA(semiconservativereplication)4DNADNA:#,(),,(),,&&,,∃,,:#%230%ChineseJournalofNatureVol.32No.4HistoryofNaturalScienceDNA,,,,???DNA,DNA?,DNA,∃[3]1.21958,MeselsonStahlDNA!∀,!DNA∀[4],DNA,,,DNADNA(),DNA,DNA,DNADNA5,(15N)(14N)DNA,1.724g/cm31.710g/cm3(a),(b)(a)DNA514NDNA15NDNADNA:96.5%15NH4CL15,DNA15N,,,15NDNA15NDNA14NH4CL,,,,DNA15NDNA14NDNA,,DNA,15N14N15N,14N,DNA14N,,,15N14N14N14N,14N,,DNA[5],14N14N,66DNA,MeselsonStahl:#,,∃:#DNA,,DNADNA∃,,15N14NDNA100∋30min,,15N14N,(),%231%自然杂志第32卷第4期0.015g/cm3,15NDNA14NDNA,715NDNA14NDNA14N15NDNA715N14NDNA22.12060(ReijiOkazaki)DNA1968!∀[6]#DNA∃:#MeselsonStahlDNA,53,35(8A),DNADNA53DNA35∃DNA,3,5,DNA53?35?2050(A.Kornberg)DNADNADNA3OH(dNTP),DNA531960,!∀#DNA∃,:#DNADNA3DNA53∃DNADNADNA53DNA,:#8B-D,:,,53,DNA∃8DNA,:(DNADNA,DNA)DNA,,,DNA,2.22.2.1脉冲标记实验1,1968!∀#DNA,∗.∃1[7],T4DNAT4DNA,DNA,3H,3H,T43H,(2s,7s,15s,30s,60s,120s)[8],DNA,%232%ChineseJournalofNatureVol.32No.4HistoryofNaturalScience,S,S,(s)S,10-13s,S,,,DNA,DNA,DNA9T4DNADNA9T4T420∋70min,DNA,3HT42s,9SDNA,DNA,DNA1000~2000,,,,DNADNA30s#9S∃,,#9S∃10,,40S5min10minDNA45S50S,,DNA(Okzakifragment)(8CD),DNA,DNA,10T4,DNA2.2.2抑制连接酶导致新生短链积累的实验,1968,!∀[9]#DNA,+.T4∃:#DNADNA,,DNA,T4DNA,,DNA∃T430,T4tsA80T4tsB2030(tsA80,tsB20)T4,20∋43∋1min,,10:#20∋%233%自然杂志第32卷第4期43∋,H3T4tsA80T4tsB20,10s20s9SDNADNA30s,40s60s,5~20S,35S,DNA,DNA,∃,30(tsA80,tsB20),,DNAT4(tsB20),,DNADNA,:#DNA,30()T443~44∋,DNA,:DNA,∃,;,,DNA,,,DNA,3OHDNA,2.2.3探测尿嘧啶片段的实验,,(dUTP)(dTTP)1,300DNA−dUTPdTTP,,dUTPDNAA%U,dUMP()DNA,(dUTPase),dUTPdUMPPPi(),dUTPDNA[10]dUTPase,dUTP,DNA,,,DNA(11),DNA,N(uracilNglycosylase)N,,,AP(APendonuclease),,,,AP,∗,[11,12]11DNANdUTPDNA,dUTP,NN,,,,DNA(dUMP),,DNADNA,,dUMP?,dUTP,dut-,%234%ChineseJournalofNatureVol.32No.4HistoryofNaturalScienceN,ung-:dut-,dUTP,dUMP,dUMPung-,,,DNA50%N,:DNA50%DNA:,[13],3OH,(leadingstrand)(laggingstrand)53DNA,,;,,(2010年4月1日收到)[1]WATSONJD,CRICKFHC.Geneticalimplicationsofthestructureofdeoxyribonucleicacid[J].Nature,1953,171:964967.[2],.[M].:,2007:151152.[3]FRUTONJS.,[M].,.:,2005:438439.[4]MESELSONM,STAHLFW.ThereplicationofDNAinescherichiacoli[J].ProcNatlAcadSciUSA,1958,44(7):671682.[5].[M].:,2006:132134.[6]OKAZAKIR,OKAZAKIT,SAKABEK,etal.Coldspringharborsymposiaonquantitativebiology[J].ProcNatlAcadSciUSA,1968,33:129143.[7]OKAZAKIR,OKAZAKIT,SAKABEK,etal.MechanismofDNAchaingrowth,∗.possiblediscontinuityandunusualsecondarystructureofnewlysynthesizedchains[J].ProcNatlAcadSciUSA,1968,59:598605.[8].[M].:,2007:9396.[9]SUGIMOTOK,OKAZAKIT,OKAZAKIR.MechanismofDNAchaingrowth,+.accumulationofnewlysynthesizedshortchainsinE.coliinfectedwithligasedefectiveT4phages[J].ProcNatlAcadSciUSA,1968,60:13561362.[10]TYEBK,NYMANP,LEHMANIR,etal.TransientaccumulationofOkazakifragmentsasaresultofuracilincorporationintonascentDNA[J].ProcNatlAcadSciUSA,1977,74(1):154157.[11]FREIFELDERDM.Molecularbiologyacomprehensiveintroductiontoprokaryotesandeukaryotes[M].JonesandBartlettPublishers,1983:277283.[12]D..()[M].,,.:,1988:183187.[13]WEAVERRF.Molecularbiology[M].3thEd.McgrawHillCompaniesInc,2004:643647.PropositionandEstablishmentofDNASemiconservativeReplicationandSemidiscontinuousReplicationXIANGYiheProfessor,DepartmentofPhysics,TsinghuaUniversity,Beijing100084,ChinaAbstractTheprocessofpropositionandestablishmentofDNAsemiconservativereplicationandsemidiscontinuousreplicationisintroduced.WatsonandCrickproposedDNAsemiconservativereplication,anditsexprimentalevidencewasgivenbyMeselsonandStahl.Okzakiproposedthediscontinuousreplicationandobtainedtheexprimentalevidenceofsemidiscontinuousreplication.Keywordssemiconservativereplication,semidiscontinuousreplication,densitygradientcentrifugation,pulselabelingexperiment,Okazakifragment,dUMPfragment(责任编辑:温文)doi:10.3969/j.issn02539608.2010.04.0146(quark),,,(strangequark),,10......,(strangelet)JackSandweiss,#,∃(AMS01)...3,AMS02AMS01Sandweiss:,SandweissApollo15gSandweiss,#AMS01,2010AMS02∃[许呆呆据NewScientist,20090829]%235%自然杂志第32卷第4期