第七章 植物根的发育

树大根深根深叶茂刨根究底追根溯源.............................1Thestructureofrootapex根尖的结构2Morphogenesisofrootapicalmeristerm

根顶端分生组织形态发生3Developmentofroothair根毛的发育4Morphogenesisoflateralroot侧根的形态发生5Genomicsofrootdevelopment根发育的基因组学Chapter10RootDevelopment根冠细胞分裂区细胞伸长区成熟区根冠细胞分裂区细胞伸长区成熟区根组织的发育成熟区（maturationzone):细胞分化的最后阶段，根毛长出细胞伸长区（zoneofcellelongation):细胞分裂已经停止,细胞伸长；细胞分裂区（zoneofcelldivision)：包括顶端分生组织，可最长延伸1mm至发育着的根组织中；这三个区的确切位置随物种、生长条件和组织分层的不同而异拟南芥的根表面结构成熟区的横切面根尖的纵截面AnatomicstructureofRAM维管束vascularbundle(v)根冠columella(col)lateralrootcap(lrc)表皮epidermis(e)中柱stele皮层cortex(c)内皮层endodermis(en)中柱鞘pericycle不活动区quiescentcent(qc)WOX5:WUSThemorphogenesisoftherootcap?CSCThemorphogenesisofendodermisandcortex1Thestructureofrootapex根尖的结构2Morphogenesisofrootapicalmeristem

根顶端分生组织形态发生3Developmentofroothair根毛的发育4Morphogenesisoflateralroot侧根的形态发生5Genomicsofrootdevelopment根发育的基因组学Chapter10RootDevelopmentWOXinteractswithsomegenes,e.g.SCR,SHRinRAMWOX?SCR在QC、内皮层、皮层初始区和已分化的内皮层表达，其功能缺失导致起始区及QC干细胞的连续性丧失；SHR在中柱细胞表达，其蛋白质转运到邻近细胞（包括QC).SHR功能丧失导致QC结构不规则，缺乏QC特异性和根部停止生长SCR和SHR是维持QC功能所必须的CelllineageWhocontrolstheinitiation?Shortroot(shr)皮层/内皮层原始细胞不分裂,根无内皮层,其余细胞分裂功能衰弱,使根生长缓慢。Scarecrow(scr)TranscriptfactorLoss-offunctionRootmeristemless(rml)Shortroot(shr)皮层/内皮层原始细胞不分裂,根无内皮层,其余细胞分裂功能衰弱,使根生长缓慢。Scarecrow(scr)TranscriptfactorLoss-offunction皮层细胞过度分裂,根特粗大。Fass(fs)Doublemutant:Scr/fsGain-offunction1Thestructureofrootapex根尖的结构2Morphogenesisofrootapicalmeristerm

根顶端分生组织形态发生3Developmentofroothair根毛的发育4Morphogenesisoflateralroot侧根的形态发生5Genomicsofrootdevelopment根发育的基因组学Chapter10RootDevelopmentHairCell(H）生毛细胞Non-haircell(N)无毛细胞Howtheroothairdeveloped?Anygeneticcontrol?拟南芥根毛发生模式图Ep:Epidermis(表皮）Co：Cortex(皮层）*：Haircell（根毛）根毛发生于位于两个皮层细胞间的表皮细胞控制根毛发生重要基因不同突变体：一：T细胞决定因子TRANSPARENTTESTAGLABRA(TTG)WEREWOLF(WER)GLABRA3(GL3)ENHANCEROFGLABRA3(EGL3)GLABRA2(GL2)二：H细胞决定因子CAPRICE(CPC),TRIPTYCHON(TRY),ENHANCEROFTRYANDCPC(ETC）SCRAMBLEDreceptor-likekinase（SCM）F,G,H,I,J实验分别说明了什么问题？小小根毛的发育,也受复杂、精细的系统控制Howaboutenvironment?GeneticcontrolofroothairdevelopmentChapter6EnvironmentalImpactonPlantDevelopmentInorganicInorganicLightTemperatureSoilInorganic磷饥饿诱导拟南芥根毛发生+P-P磷饥饿诱导澳大利亚野生植物的排根结构-P+P1Thestructureofrootapex根尖的结构2Morphogenesisofrootapicalmeristerm

根顶端分生组织形态发生3Developmentofroothair根毛的发育4Morphogenesisoflateralroot侧根的形态发生5Genomicsofrootdevelopment根发育的基因组学Chapter10RootDevelopmentHowlateralrootsformation?侧根原基起源于初生根RAM后面成熟区紧邻木质部的中柱鞘细胞LateralrootformationinwillowSure?拟南芥侧根LR发生模式图（纵切）：I：一对LR原基细胞；II：细胞发生横向不对称分裂,形成内层（IL)和外层（OL);III:OL层细胞进行平周分裂形成三层LR原基细胞；IV:IL层细胞进行平周分裂形成四层LR原基细胞；V：LR原基细胞穿过内皮层；VI-VIII:LR原基细胞依次穿过皮层、表皮ILOLLateralrootprimordiadevelopmentinArabidopsistracedwith35S:AC:GUSWhatfactorsaffectlateralrootdevelopment?AuxinWhatfactorsaffectlateralrootdevelopment?Auxin1.Laskowski等,1995:侧根原基的诱导需auxin参与。侧根原基发育至3-5层细胞时,auxin就不必需了。2.Superroot1(sur1):过度产生生长素,生成大量侧根和不定根。Atleasttwoevidences:Anydirectevidences?1Thestructureofrootapex根尖的结构2Morphogenesisofrootapicalmeristerm

根顶端分生组织形态发生3Developmentofroothair根毛的发育4Morphogenesisoflateralroot侧根的形态发生5Genomicsofrootdevelopment根发育的基因组学Chapter10RootDevelopmentHowmanygenescontroltherootdevelopment?实验设计：取根尖不同发育阶段不同部位组织提取RNA，和DNA芯片进行杂交，分析基因表达情况不同区域的细胞发育的不同阶段Rootcanbedividedinto5radialzonesand3developmentalstagesSomegenesexpressedinsomespecificzones,eg.WolinStelezoneWoodenleg(Wol)维管束发育不全怎样选取不同类型的细胞？在特定细胞群中表达GFP的转基因株系GFPTATAWoodenLegWoodenleg:GFPtransgeniclineofArabidopsisGFPTATAWoodenLegWoodenleg:GFPtransgeniclineofArabidopsisSortedcellsRNA22,000DNAchip: 22,000genesDetected: 10,492genesSortedcellsRNA4timeshigherthantheminimalexpressionvalue:5,717genes22,000DNAchip: 22,000genesDetected: 10,492genesThegeneswereclusteredinto8groupsGlobalexpressionmapdepictingmajorpatternsofgeneactivity全基因组基因表达图谱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