植物基因组大小进化的研究进展

HEREDITAS(Beijing)20095,31(5):464―470ISSN0253-9772综述收稿日期:2008−11−21;修回日期:2008−12−23基金项目:(KSCX2-YW-N-030),,(30800624)(20055003059-45)作者简介:(1979−),,,,Tel:[phone];E-mail:[e-mail]通讯作者:(1973−),,,,Tel:[phone];E-mail:[e-mail]:10.3724/SP.J.1005.2009.00464植物基因组大小进化的研究进展陈建军,王瑛,430074不同的真核生物之间基因组大小差异很大,并与生物体复杂性不相关,在基因组中存在大量的非编码DNA序列是造成这种差异的主要原因,特别是转座子序列。文章综述了植物基因组大小差异以及引起这种差异的主要进化动力的最新研究进展。植物基因组多倍化和转座子积累是导致基因组增大的主要动力,而同源不平等重组和非正规重组则是驱动基因组DNA丢失的潜在动力,以制约基因组无限制地增大。文中还讨论了植物基因组大小进化方向,即总体趋势是朝着增大的方向进化,某些删除机制主要是削弱这种增大作用但不能逆转。基因组大小;进化动力;转座子;非编码DNARecentprogressinplantgenomesizeevolutionCHENJian-Jun,WANGYingWuhanBotanicalGarden,ChineseAcademyofSciences,Wuhan430074,ChinaAbstract:Ithasbeenknownthateukaryoticgenomesspanawiderangeofsizesregardlessoforganismcomplexity.Theobserveddifferencesingenomesizeareprimarilyduetopolyploidylevelandabundanceofnon-codingDNA,especiallythecontributionoftransposableelements(TEs).Herewereviewedthecurrentprogressingenomesizevariationofplantspeciesandtheunderlyingevolutionaryforcesthatcontributetogenomeexpansionorcontraction.Polyploidizationandtheaccumulationoftransposableelementaretheprimarycontributorstogenomeexpansion.AstothemechanismsofDNAloss,unequalhomologousrecombinationandillegitimaterecombinationarethoughttobethecounterbalancestotheunlimitedexpansionofagenome.Theevolutionarydirectionofplantgenomesizeisalsodiscussed,whichtendstofavorlargerge-nomeswithdeletionmechanismsactingtoonlyattenuategenomeexpansionbutnotreverse.Keywords:genomesize;evolutionaryforces;transposableelements;non-codingDNA,DNAC(C-value),[1]CDNA[2],pg(picogram)Mb(millionbasepair),1pg978Mb[3],5150DNAC(ThePlantDNAC-valuesDatabase)[4],,(Genliseamaragre-taeHutch.),63Mb[5];(FritillariaassyriacaBaker.),127Gb[6],2000DNA(Non-codingDNA)5:465[7],DNA,DNA,DNA(JunkDNA)11.1C(C-valueparadox)C(C-valueenigma),“C”[8],,;,,“C”DNA,DNA2003“”,“C-valueenigma”“C-valuepara-dox”,:(1),DNA,(2)DNA,DNA,(3)DNA(4),DNA,CC[9~12]1.2C(C):(1)AFLP,,[13,14];(2),,[15];(3),[16];(4),C(),()[17];(5)C,,,DNA,DNA,C[18];(6)C,[19~21],1.3CC(Flowcytometry)(Feulgenmicroden-sitometry),,,,,,C,[22],1.4[23],,[16][24],[25],Knight[26],(,,),(,)22.1“”“”Thomas[8]1971“C”,466HEREDITAS(Beijing)200931,,,“”,“”Lynch[7](Ne),,Neu(u),,,,,[27,28],,,,Lynch“”,,[29,30],DNA,“DNA”Vinogradov[31~35]“genomedesign”:,GC(GC-rich),,,,()GC(GC-poor),,,,,,DNA;,,,DNA,,DNA,2.2,(DNA)[36~39],,,[40],,,,30%~65%[41]“”DNA,,,,,LTR,[42],2.5pg(1C),80%,[43],“DNA”,,[44~46],,,[46~50]Rouzic[51],,(,),,(),,,,,,“-”,,50%[52],3,1200Mb2400Mb,[53],(1.6~1.8pg/2C)(4.9~5.5pg/2C),5:467,240kbadh1,LTR,,,LTR[42,52,53],,[54]LTR10000,1000,[55],,,[55](ViciapannonicaCrantz.),gypsy38%,,[56]Hawkins[57]3,40%~65%,,copia-like(Gossypiumrai-mondiiUlb.),gypsy-like,gypsy-likeGorge3(OryzaaustraliensisDomin.)[58](Lotusjaponi-cusL.)[59]2.3,indel(insertion-deletion)DNA,DNADNA[60],,DNA[37],(Replicationslippage)(Unequalcrossingover),DNAindel,Petrov[61](Pseudogenes),11“DNA(theDNAlosshypothesis)”,indelDNA[38,62],indel[38]DNA,,(Unequalhomologousrecombination)(Illegitimaterecombination)DNA,LTRLTR,LTRsoloLTR(LTR,)soloLTR[63],DNA[64~66][67][68][69,70]soloLTR2.4,Bennetzen[71]DNA,DNA,,DNA,[37,72],[73]Leitch[6],,,Hawkins[39,74],468HEREDITAS(Beijing)200931,,DNA,,O.glaberrimaSteud.,,O.glaberrimaO.sativa,O.glaberrima,LTR,O.sativa(,O.indica2%,O.japonica6%)[75],O.sativaDNA,DNA,DNA,O.sativa,[36,57,73,76][77],Hawkins[39],,,,,,“(one-waytickettogenomicobesity)[71]”3,“”,indel,,“”,,,,,,,,,参考文献(References):[1]SwiftH.Theconstancyofdeoxyribosenucleicacidinplantnuclei.ProcNatlAcadSciUSA,1950,36(11):643–654.[2]BennettMD,BhandolP,LeitchIJ.NuclearDNAamountsinangiospermsandtheirmodernuses-807newestimates.AnnBot,2000,86(4):859–909.[3]DolezelJ,BartosJ,VoglmayrH,GreilhuberJ.NuclearDNAcontentandgenomesizeoftroutandhuman.Cy-tometry,2003,51(2):127–128.[4]BennettMD,LeitchIJ.PlantDNAC-valuesdatabase(re-lease3.0,Dec.2004).[5]GreilhuberJ,BorschT,MullerK,WorbergA,PorembskiS,BarthlottW.SmallestangiospermgenomesfoundinLentibulariaceae,withchromosomesofbacterialsize.PlantBiol(Stuttg),2006,8(6):770–777.[6]LeitchIJ,SoltisDE,SoltisPS,BennettMD.EvolutionofDNAamountsacrosslandplants(Embryophyta).AnnBot,2005,95(1):207–217.[7]LynchM,ConeryJS.Theoriginsofgenomecomplexity.Science,2003,302(5649):1401–1404.[8]ThomasCA,Jr.Thegeneticorganizationofchromosomes.AnnuRevGenet,1971,5:237–256.[9]GregoryTR.ThebiggertheC-value,thelargerthecell:genomesizeandredbloodcellsizeinvertebrates.BloodCellsMolDis,2001,27(5):830–843.[10]GregoryTR.Coincidence,coevolution,orcausation?DNAcontent,cellsize,andtheC-valueenigma.BiolRevCambPhilosSoc,2001,76(1):65–101.[11]GregoryTR.Genomesizeanddevelopmentalcomplexity.Genetica,2002,115(1):131–146.[12]GregoryTR.Abird's-eyeviewoftheC-valueenigma:genomesize,cellsize,andmetabolicrateintheclassaves.Evolution,2002,56(1):121–130.[13]FayMF,CowanRS,LeitchIJ.TheeffectsofnuclearDNAcontent(C-value)onthequalityandutilityofAFLPfin-gerprints.AnnBot,2005,95(1):237–246.[14]HanTH,vanEckHJ,DeJeuMJ,JacobsenE.Optimiza-