第七章 植物根的發(fā)育

樹(shù)大根深根深葉茂刨根究底追根溯源.............................1Thestructureofrootapex根尖的結(jié)構(gòu)2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態(tài)發(fā)生3Developmentofroothair根毛的發(fā)育4Morphogenesisoflateralroot側(cè)根的形態(tài)發(fā)生5Genomicsofrootdevelopment根發(fā)育的基因組學(xué)Chapter10RootDevelopment根冠細(xì)胞分裂區(qū)細(xì)胞伸長(zhǎng)區(qū)成熟區(qū)根冠細(xì)胞分裂區(qū)細(xì)胞伸長(zhǎng)區(qū)成熟區(qū)根組織的發(fā)育成熟區(qū)（maturationzone):細(xì)胞分化的最后階段，根毛長(zhǎng)出細(xì)胞伸長(zhǎng)區(qū)（zoneofcellelongation):細(xì)胞分裂已經(jīng)停止,細(xì)胞伸長(zhǎng)；細(xì)胞分裂區(qū)（zoneofcelldivision)：包括頂端分生組織，可最長(zhǎng)延伸1mm至發(fā)育著的根組織中；這三個(gè)區(qū)的確切位置隨物種、生長(zhǎng)條件和組織分層的不同而異擬南芥的根表面結(jié)構(gòu)成熟區(qū)的橫切面根尖的縱截面AnatomicstructureofRAM維管束vascularbundle(v)根冠columella(col)lateralrootcap(lrc)表皮epidermis(e)中柱stele皮層cortex(c)內(nèi)皮層endodermis(en)中柱鞘pericycle不活動(dòng)區(qū)quiescentcent(qc)WOX5:WUSThemorphogenesisoftherootcap?CSCThemorphogenesisofendodermisandcortex1Thestructureofrootapex根尖的結(jié)構(gòu)2Morphogenesisofrootapicalmeristem

根頂端分生組織形態(tài)發(fā)生3Developmentofroothair根毛的發(fā)育4Morphogenesisoflateralroot側(cè)根的形態(tài)發(fā)生5Genomicsofrootdevelopment根發(fā)育的基因組學(xué)Chapter10RootDevelopmentWOXinteractswithsomegenes,e.g.SCR,SHRinRAMWOX?SCR在QC、內(nèi)皮層、皮層初始區(qū)和已分化的內(nèi)皮層表達(dá)，其功能缺失導(dǎo)致起始區(qū)及QC干細(xì)胞的連續(xù)性喪失；SHR在中柱細(xì)胞表達(dá)，其蛋白質(zhì)轉(zhuǎn)運(yùn)到鄰近細(xì)胞（包括QC).SHR功能喪失導(dǎo)致QC結(jié)構(gòu)不規(guī)則，缺乏QC特異性和根部停止生長(zhǎng)SCR和SHR是維持QC功能所必須的CelllineageWhocontrolstheinitiation?Shortroot(shr)皮層/內(nèi)皮層原始細(xì)胞不分裂,根無(wú)內(nèi)皮層,其余細(xì)胞分裂功能衰弱,使根生長(zhǎng)緩慢。Scarecrow(scr)TranscriptfactorLoss-offunctionRootmeristemless(rml)Shortroot(shr)皮層/內(nèi)皮層原始細(xì)胞不分裂,根無(wú)內(nèi)皮層,其余細(xì)胞分裂功能衰弱,使根生長(zhǎng)緩慢。Scarecrow(scr)TranscriptfactorLoss-offunction皮層細(xì)胞過(guò)度分裂,根特粗大。Fass(fs)Doublemutant:Scr/fsGain-offunction1Thestructureofrootapex根尖的結(jié)構(gòu)2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態(tài)發(fā)生3Developmentofroothair根毛的發(fā)育4Morphogenesisoflateralroot側(cè)根的形態(tài)發(fā)生5Genomicsofrootdevelopment根發(fā)育的基因組學(xué)Chapter10RootDevelopmentHairCell(H）生毛細(xì)胞Non-haircell(N)無(wú)毛細(xì)胞Howtheroothairdeveloped?Anygeneticcontrol?擬南芥根毛發(fā)生模式圖Ep:Epidermis(表皮）Co：Cortex(皮層）*：Haircell（根毛）根毛發(fā)生于位于兩個(gè)皮層細(xì)胞間的表皮細(xì)胞控制根毛發(fā)生重要基因不同突變體：一：T細(xì)胞決定因子TRANSPARENTTESTAGLABRA(TTG)WEREWOLF(WER)GLABRA3(GL3)ENHANCEROFGLABRA3(EGL3)GLABRA2(GL2)二：H細(xì)胞決定因子CAPRICE(CPC),TRIPTYCHON(TRY),ENHANCEROFTRYANDCPC(ETC）SCRAMBLEDreceptor-likekinase（SCM）F,G,H,I,J實(shí)驗(yàn)分別說(shuō)明了什么問(wèn)題？小小根毛的發(fā)育,也受復(fù)雜、精細(xì)的系統(tǒng)控制Howaboutenvironment?GeneticcontrolofroothairdevelopmentChapter6EnvironmentalImpactonPlantDevelopmentInorganicInorganicLightTemperatureSoilInorganic磷饑餓誘導(dǎo)擬南芥根毛發(fā)生+P-P磷饑餓誘導(dǎo)澳大利亞野生植物的排根結(jié)構(gòu)-P+P1Thestructureofrootapex根尖的結(jié)構(gòu)2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態(tài)發(fā)生3Developmentofroothair根毛的發(fā)育4Morphogenesisoflateralroot側(cè)根的形態(tài)發(fā)生5Genomicsofrootdevelopment根發(fā)育的基因組學(xué)Chapter10RootDevelopmentHowlateralrootsformation?側(cè)根原基起源于初生根RAM后面成熟區(qū)緊鄰木質(zhì)部的中柱鞘細(xì)胞LateralrootformationinwillowSure?擬南芥?zhèn)雀鵏R發(fā)生模式圖（縱切）：I：一對(duì)LR原基細(xì)胞；II：細(xì)胞發(fā)生橫向不對(duì)稱(chēng)分裂,形成內(nèi)層（IL)和外層（OL);III:OL層細(xì)胞進(jìn)行平周分裂形成三層LR原基細(xì)胞；IV:IL層細(xì)胞進(jìn)行平周分裂形成四層LR原基細(xì)胞；V：LR原基細(xì)胞穿過(guò)內(nèi)皮層；VI-VIII:LR原基細(xì)胞依次穿過(guò)皮層、表皮ILOLLateralrootprimordiadevelopmentinArabidopsistracedwith35S:AC:GUSWhatfactorsaffectlateralrootdevelopment?AuxinWhatfactorsaffectlateralrootdevelopment?Auxin1.Laskowski等,1995:側(cè)根原基的誘導(dǎo)需auxin參與。側(cè)根原基發(fā)育至3-5層細(xì)胞時(shí),auxin就不必需了。2.Superroot1(sur1):過(guò)度產(chǎn)生生長(zhǎng)素,生成大量側(cè)根和不定根。Atleasttwoevidences:Anydirectevidences?1Thestructureofrootapex根尖的結(jié)構(gòu)2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態(tài)發(fā)生3Developmentofroothair根毛的發(fā)育4Morphogenesisoflateralroot側(cè)根的形態(tài)發(fā)生5Genomicsofrootdevelopment根發(fā)育的基因組學(xué)Chapter10RootDevelopmentHowmanygenescontroltherootdevelopment?實(shí)驗(yàn)設(shè)計(jì)：取根尖不同發(fā)育階段不同部位組織提取RNA，和DNA芯片進(jìn)行雜交，分析基因表達(dá)情況不同區(qū)域的細(xì)胞發(fā)育的不同階段Rootcanbedividedinto5radialzonesand3developmentalstagesSomegenesexpressedinsomespecificzones,eg.WolinStelezoneWoodenleg(Wol)維管束發(fā)育不全怎樣選取不同類(lèi)型的細(xì)胞？在特定細(xì)胞群中表達(dá)GFP的轉(zhuǎn)基因株系GFPTATAWoodenLegWoodenleg:GFPtransgeniclineofArabidopsisGFPTATAWoodenLegWoodenleg:GFPtransgeniclineofArabidopsisSortedcellsRNA22,000DNAchip: 22,000genesDetected: 10,492genesSortedcellsRNA4timeshigherthantheminimalexpressionvalue:5,717genes22,000DNAchip: 22,000genesDetected: 10,492genesThegeneswereclusteredinto8groupsGlobalexpressionmapdepictingmajorpatternsofgeneactivity全基因組基因表達(dá)圖譜5717genesclusteredinto8groupsWeakStrong12345678GlobalexpressionmapdepictingmajorpatternsofgeneactivityRapidlycelldivisionRapidlycelldivisionRapidlycelldivisionGlobalexpressionmapdepictingmajorpatternsofgeneactivitySignaltransductionduringcellmaturation:GA,Stele,endodermis,cortexstage2,LED2:JA,Lateralrootcapstage1,LED5:Auxin,Stelestage3,LED1:JA,Epidermisstage2,LED4Hormoneactivitycenters:GA,Stele,endodermis,cortexstage2,LED2:JA,Lateralrootcapstage1,LED5:Auxin,Stelestage3,LED1:JA,Epidermisstage2,LED4H