樹大根深根深葉茂刨根究底追根溯源.............................1Thestructureofrootapex根尖的結構2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態發生3Developmentofroothair根毛的發育4Morphogenesisoflateralroot側根的形態發生5Genomicsofrootdevelopment根發育的基因組學Chapter10RootDevelopment根冠細胞分裂區細胞伸長區成熟區根冠細胞分裂區細胞伸長區成熟區根組織的發育成熟區（maturationzone):細胞分化的最后階段，根毛長出細胞伸長區（zoneofcellelongation):細胞分裂已經停止,細胞伸長；細胞分裂區（zoneofcelldivision)：包括頂端分生組織，可最長延伸1mm至發育著的根組織中；這三個區的確切位置隨物種、生長條件和組織分層的不同而異擬南芥的根表面結構成熟區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)內皮層endodermis(en)中柱鞘pericycle不活動區quiescentcent(qc)WOX5:WUSThemorphogenesisoftherootcap?CSCThemorphogenesisofendodermisandcortex1Thestructureofrootapex根尖的結構2Morphogenesisofrootapicalmeristem

根頂端分生組織形態發生3Developmentofroothair根毛的發育4Morphogenesisoflateralroot側根的形態發生5Genomicsofrootdevelopment根發育的基因組學Chapter10RootDevelopmentWOXinteractswithsomegenes,e.g.SCR,SHRinRAMWOX?SCR在QC、內皮層、皮層初始區和已分化的內皮層表達，其功能缺失導致起始區及QC干細胞的連續性喪失；SHR在中柱細胞表達，其蛋白質轉運到鄰近細胞（包括QC).SHR功能喪失導致QC結構不規則，缺乏QC特異性和根部停止生長SCR和SHR是維持QC功能所必須的CelllineageWhocontrolstheinitiation?Shortroot(shr)皮層/內皮層原始細胞不分裂,根無內皮層,其余細胞分裂功能衰弱,使根生長緩慢。Scarecrow(scr)TranscriptfactorLoss-offunctionRootmeristemless(rml)Shortroot(shr)皮層/內皮層原始細胞不分裂,根無內皮層,其余細胞分裂功能衰弱,使根生長緩慢。Scarecrow(scr)TranscriptfactorLoss-offunction皮層細胞過度分裂,根特粗大。Fass(fs)Doublemutant:Scr/fsGain-offunction1Thestructureofrootapex根尖的結構2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態發生3Developmentofroothair根毛的發育4Morphogenesisoflateralroot側根的形態發生5Genomicsofrootdevelopment根發育的基因組學Chapter10RootDevelopmentHairCell(H）生毛細胞Non-haircell(N)無毛細胞Howtheroothairdeveloped?Anygeneticcontrol?擬南芥根毛發生模式圖Ep:Epidermis(表皮）Co：Cortex(皮層）*：Haircell（根毛）根毛發生于位于兩個皮層細胞間的表皮細胞控制根毛發生重要基因不同突變體：一：T細胞決定因子TRANSPARENTTESTAGLABRA(TTG)WEREWOLF(WER)GLABRA3(GL3)ENHANCEROFGLABRA3(EGL3)GLABRA2(GL2)二：H細胞決定因子CAPRICE(CPC),TRIPTYCHON(TRY),ENHANCEROFTRYANDCPC(ETC）SCRAMBLEDreceptor-likekinase（SCM）F,G,H,I,J實驗分別說明了什么問題？小小根毛的發育,也受復雜、精細的系統控制Howaboutenvironment?GeneticcontrolofroothairdevelopmentChapter6EnvironmentalImpactonPlantDevelopmentInorganicInorganicLightTemperatureSoilInorganic磷饑餓誘導擬南芥根毛發生+P-P磷饑餓誘導澳大利亞野生植物的排根結構-P+P1Thestructureofrootapex根尖的結構2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態發生3Developmentofroothair根毛的發育4Morphogenesisoflateralroot側根的形態發生5Genomicsofrootdevelopment根發育的基因組學Chapter10RootDevelopmentHowlateralrootsformation?側根原基起源于初生根RAM后面成熟區緊鄰木質部的中柱鞘細胞LateralrootformationinwillowSure?擬南芥側根LR發生模式圖（縱切）：I：一對LR原基細胞；II：細胞發生橫向不對稱分裂,形成內層（IL)和外層（OL);III:OL層細胞進行平周分裂形成三層LR原基細胞；IV:IL層細胞進行平周分裂形成四層LR原基細胞；V：LR原基細胞穿過內皮層；VI-VIII:LR原基細胞依次穿過皮層、表皮ILOLLateralrootprimordiadevelopmentinArabidopsistracedwith35S:AC:GUSWhatfactorsaffectlateralrootdevelopment?AuxinWhatfactorsaffectlateralrootdevelopment?Auxin1.Laskowski等,1995:側根原基的誘導需auxin參與。側根原基發育至3-5層細胞時,auxin就不必需了。2.Superroot1(sur1):過度產生生長素,生成大量側根和不定根。Atleasttwoevidences:Anydirectevidences?1Thestructureofrootapex根尖的結構2Morphogenesisofrootapicalmeristerm

根頂端分生組織形態發生3Developmentofroothair根毛的發育4Morphogenesisoflateralroot側根的形態發生5Genomicsofrootdevelopment根發育的基因組學Chapter10RootDevelopmentHowmanygenescontroltherootdevelopment?實驗設計：取根尖不同發育階段不同部位組織提取RNA，和DNA芯片進行雜交，分析基因表達情況不同區域的細胞發育的不同階段Rootcanbedividedinto5radialzonesand3developmentalstagesSomegenesexpressedinsomespecificzones,eg.WolinStelezoneWoodenleg(Wol)維管束發育不全怎樣選取不同類型的細胞？在特定細胞群中表達GFP的轉基因株系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