《細(xì)胞的增殖和調(diào)控》課件

MathematicalBiosciencesInstitute(OhioStateUniv),2October2003Chapter11

Cellcycle1精選課件pptMathematicalBiosciencesInsti1introductionofthecellcycle2精選課件ppt1introductionofthecellcy由細(xì)胞分裂結(jié)束到下一次細(xì)胞分裂結(jié)束所經(jīng)歷的過(guò)程，叫細(xì)胞周期。分為4個(gè)期：–G1期(gap1)，指從有絲分裂完成到期DNA復(fù)制之前的間隙時(shí)間。–S期(synthesisphase)，指DNA復(fù)制的時(shí)期。–G2期(gap2)，指DNA復(fù)制完成到有絲分裂開(kāi)始之前的一段時(shí)間。–M期又稱D期(mitosisordivision)，細(xì)胞分裂開(kāi)始到結(jié)束。3精選課件ppt由細(xì)胞分裂結(jié)束到下一次細(xì)胞分裂結(jié)束所經(jīng)歷的過(guò)程，叫細(xì)胞周期。4精選課件ppt4精選課件ppt2001NobelPrizeLelandH.Hartwell1970s“Checkpoint”Yeastgenetics~100CDCgenesStartgeneTimHunt1980sCyclinsSeaUrchinsPaulM.Nurse1970sCDKsyeast5精選課件ppt2001NobelPrizeLelandH.Hart2MPF(Mphase–promotingfactor),Cyclin,CDK

2.1MPFfound2.2MPFcomponentsCyclin(B)CDK(cyclindependentkinase)6精選課件ppt2MPF(Mphase–promotingfacto1970sRao和Johnson發(fā)現(xiàn)與M期細(xì)胞(Hela)融合的間期細(xì)胞染色體發(fā)生凝縮，稱為早熟凝集染色體(prematurelycondensedchromosome，PCC)。–G1期PCC為單線狀，因DNA未復(fù)制。–S期PCC為粉末狀，因DNA由多個(gè)部位開(kāi)始復(fù)制。–G2期PCC為雙線染色體，說(shuō)明DNA復(fù)制已完成。?甚至不同類(lèi)的M期細(xì)胞也可誘導(dǎo)PCC產(chǎn)生，說(shuō)明M期細(xì)胞具有促進(jìn)間期細(xì)胞進(jìn)行分裂的因子，即成熟促進(jìn)因子(maturationpromotingfactor，MPF)。7精選課件ppt1970sRao和Johnson發(fā)現(xiàn)與M期細(xì)胞(Hela)G1phasefusewithMphase2.1MPFfound8精選課件pptG1phasefusewithMphase2.1s

phasefusewithMphase9精選課件pptsphasefusewithMphase9精選課件G2phasefusewithMphase10精選課件pptG2phasefusewithMphase10精選MPFManfredLohkaandJimMaller(UCHSC) -usedcellfreeassaytopurifyMPF -testedvariouscytosolicfractionsforMPFactivityMPFisa2subunitproteinkinase -32kDaand45kDa11精選課件pptMPFManfredLohkaandJimMalleMPFCdk12精選課件pptMPFCdk12精選課件pptHistoryofMPFPCCM-phaseTriggerMPFP32andP45,kinase非洲爪蟾(1988)Cdcgenefoundin

yeastP34cdc2triggerG2/MP34cdc2bindwithP56cdc13active

Cyclinfoundinurchin,keyfactorForM-phase(1983)

MPFincludeCdkandcyclinp32=P34cdc2=CDKP45=P56cdc13=cyclinB13精選課件pptHistoryofMPFPCCM-phaseTrig2.2Cyclin1983firstfoundG1-phase:cyclinC,cyclinD,cyclinECln1,Cln2,Cln3(Yeast)M-phase:cyclinA,cyclinB,Comparativelystable14精選課件ppt2.2Cyclin1983firstfound14精A2DestroyboxCyclinboxB1PEST,G1cyclinrenewalCDifferentCyclinexpressedindifferentcellcyclephaseBindwithDifferentCDK,regulateCDKkinaseactivity特點(diǎn)：在細(xì)胞周期中呈周期性變化。含有一段約100個(gè)氨基酸的保守序列，稱為周期蛋白框，介導(dǎo)周期蛋白與CDK結(jié)合。15精選課件pptA2DestroyboxCyclinboxB1PEST16精選課件ppt16精選課件pptRegulationofmitoticcyclinlevelsincyclingcells.

17精選課件pptRegulationofmitoticcyclinlMPFregulationwaselucidatedbyTimHunt’sdiscoveryofCyclins18精選課件pptMPFregulationwaselucidatedPSTAIREantibodyBindsALLCDK’s2.3CDK

CyclindependkinaseCDKICDKkinasedomainCdk1=cdc2Cdk3cdk819精選課件pptPSTAIREantibody2.3CDKCDKICD20精選課件ppt20精選課件ppt細(xì)胞周期控制21精選課件ppt細(xì)胞周期控制21精選課件ppt細(xì)胞周期檢驗(yàn)點(diǎn)（checkpoint）

組成：感受器、信號(hào)傳導(dǎo)通路、效應(yīng)器。?主要檢驗(yàn)點(diǎn)：–G1/S檢驗(yàn)點(diǎn)：DNA是否損傷？細(xì)胞外環(huán)境是否適宜？細(xì)胞體積是否足夠大？在酵母中稱start點(diǎn)，在哺乳動(dòng)物中稱R點(diǎn)(restrictionpoint)。–S期檢驗(yàn)點(diǎn)：DNA復(fù)制是否完成？–G2/M檢驗(yàn)點(diǎn)：DNA是否損傷？細(xì)胞體積是否足夠大？–中-后期檢驗(yàn)點(diǎn)：紡錘體組裝檢驗(yàn)點(diǎn)。六、細(xì)胞周期檢驗(yàn)點(diǎn)（checkpoint）22精選課件ppt細(xì)胞周期檢驗(yàn)點(diǎn)（checkpoint）

組成：感受器、信號(hào)3.1TheG1/SCheckpoint環(huán)境因素生長(zhǎng)因子內(nèi)部因素DNA損傷23精選課件ppt3.1TheG1/SCheckpoint環(huán)境因素23G1cyclinD(D1,D2,D3),E,AG1CDK,CDK2,4,6cyclinD+CDK4,6cyclinE,A+CDK2cyclinD(D1,D2,D3)iskeyfactorforG1/ScyclinEiskeyfactorforstartups-phaseG1周期蛋白通過(guò)泛素結(jié)合PEST降解24精選課件pptG1cyclinD(D1,D2,D3),E,A24精選課Oringinrecognitioncomplex,復(fù)制起始復(fù)合物Orc1-6DNAreplication-licensingfactortheoryMinichromosomemaintenanceprotein,Mcm2-725精選課件pptOringinrecognitioncomplex,復(fù)3.2S/G2/M阻止DNA未完全復(fù)制時(shí)啟動(dòng)M期只有DNA復(fù)制正確完成，方可啟動(dòng)未復(fù)制完成的DNA會(huì)釋放一些信號(hào)。導(dǎo)致細(xì)胞周期運(yùn)轉(zhuǎn)受阻

CDC25活性低但Wee1活性高，MPF不能活化 26精選課件ppt3.2S/G2/M阻止DNA未完全復(fù)制時(shí)啟動(dòng)M期26精選MPFinactivate27精選課件pptMPFinactivate27精選課件ppt3.3M-phaseregulationMPFactivateMphasecheckpoint28精選課件ppt3.3M-phaseregulationMPFactiMPF&theG2CheckpointMPF-pushescellpastG2checkpoint29精選課件pptMPF&theG2CheckpointMPF-puThr161Tyr14,15P30精選課件pptThr161Tyr14,15P30精選課件pptMPF活化M期CDK的激活起始于分裂期cyclin的積累。?結(jié)合cyclinB的CDK1被Wee1將Thr14和Tyr15磷酸化而不具有活性，使CDK/cyclin不斷積累。?在M期，Wee1的活性下降，CDC25使CDK去磷酸化，去除了CDK活化的障礙。?CDK的激活需要Thr161的磷酸化，它是在CDK激酶(CDKactivatingkinaseCAK)的作用下完成的。31精選課件pptMPF活化M期CDK的激活起始于分裂期cyclin的積累。3Tyr15Inhibitory:AddedbyWee1RemovedbyCdc25Thr160Activating:CDKaddsafterCyclinbinding32精選課件pptTyr15Thr16032精選課件pptcyclinB+CDKinactiveWee1/mik1andCDKKinaseActiveCDK14,15amicacidInactivepre-MPFCDK160+p,14.15-pCdc25cWee1/mik1CDKKinase33精選課件pptcyclinB+CDKinactiveWee1/mik1MPFinducesmultiplenuclearandcytoplasmicchangesattheonsetofMphase,bothbyactivatingotherproteinkinasesandbyphosphorylatingproteinssuchascondensinsandthenuclearlamins.34精選課件pptMPFinducesmultiplenuclearaG1SG2MG1G1SG2MG135精選課件pptG1SG2MG1G1SG2MG135精選課件ppt◆Mphasecheckpoint:●檢驗(yàn)染色體是否連接到紡錘體上36精選課件ppt◆Mphasecheckpoint:36精選課件pp后期促進(jìn)復(fù)合物APC與M期調(diào)控APC:AnaphasePromotingComplexM期向后期轉(zhuǎn)換依賴嚴(yán)格調(diào)控APC1-8APC調(diào)控CyclinB和其他蛋白泛素化降解紡崔體裝配檢驗(yàn)點(diǎn)控制APC活性37精選課件ppt后期促進(jìn)復(fù)合物APC與M期調(diào)控APC:AnaphaseMad2Cdc2038精選課件pptMad2Cdc2038精選課件ppt周期蛋白降解39精選課件ppt周期蛋白降解39精選課件ppt瑞典皇家科學(xué)院6日宣布，將2004年諾貝爾化學(xué)獎(jiǎng)授予以色列科學(xué)家阿龍·切哈諾沃、阿夫拉姆·赫什科和美國(guó)科學(xué)家歐文·羅斯，以表彰他們發(fā)現(xiàn)了泛素調(diào)節(jié)的蛋白質(zhì)降解。其實(shí)他們的成果就是發(fā)現(xiàn)了一種蛋白質(zhì)“死亡”的重要機(jī)理死亡之吻40精選課件ppt瑞典皇家科學(xué)院6日宣布，將2004年諾貝爾化學(xué)獎(jiǎng)授予以色列科ProteindegradationNeednotenergy,onlyneedenzymeNeedenergy,certaintime,certainpositionandcertaindirectionproteindegradation41精選課件pptProteindegradationNeednote一種被稱為泛素的多肽在需要能量的蛋白質(zhì)降解過(guò)程中扮演著重要角色。這種多肽由76個(gè)氨基酸組成，它最初是從小牛的胰臟中分離出來(lái)的。它就像標(biāo)簽一樣，被貼上標(biāo)簽的蛋白質(zhì)就會(huì)被運(yùn)送到細(xì)胞內(nèi)的“垃圾處理廠”，在那里被降解。42精選課件ppt一種被稱為泛素的多肽在需要能量的蛋白質(zhì)降解過(guò)程中扮演著重要角43精選課件ppt43精選課件pptPolyubiquitinationofmitoticcyclins44精選課件pptPolyubiquitinationofmitotic原來(lái)細(xì)胞中存在著E1、E2和E3三種酶，它們各有分工。E1負(fù)責(zé)激活泛素分子。泛素分子被激活后就被運(yùn)送到E2上，E2負(fù)責(zé)把泛素分子綁在需要降解的蛋白質(zhì)上。但E2并不認(rèn)識(shí)指定的蛋白質(zhì)，這就需要E3幫助。E3具有辨認(rèn)指定蛋白質(zhì)的功能。當(dāng)E2攜帶著泛素分子在E3的指引下接近指定蛋白質(zhì)時(shí)，E2就把泛素分子綁在指定蛋白質(zhì)上。這一過(guò)程不斷重復(fù)，指定蛋白質(zhì)上就被綁了一批泛素分子。45精選課件ppt原來(lái)細(xì)胞中存在著E1、E2和E3三種酶，它們各有分工。E1負(fù)HighEnergyThioesterBond,canbetransferredfromE1toE2,E3,orsubstrateUbiquitinisTransferredviaThioesterBonds46精選課件pptHighEnergyThioesterBond,UbiMitoticCyclinsareDestroyedbyUbiquitin-DependentProteolysisproteosome47精選課件pptMitoticCyclinsareDestroyedSummary48精選課件pptSummary48精選課件ppt4ModelofcellcycleYeastSizeandMorphologyThroughtheCellCycleThestagesofmitosisandcytokinesisinananimalcell.

49精選課件ppt4ModelofcellcycleYeastSiBuddingyeast50精選課件pptBuddingyeast50精選課件pptThestagesofmitosisandcytokinesisinananimalcell.

51精選課件pptThestagesofmitosisandcyto5cellcyclecheckmethods細(xì)胞周期的時(shí)間長(zhǎng)短與物種的細(xì)胞類(lèi)型有關(guān)。通常G1期持續(xù)時(shí)間差異較大，M期最短約0.5～4.5小時(shí)。?標(biāo)記有絲分裂百分率法（percentagelabeledmitoses，PLM）：對(duì)測(cè)定細(xì)胞進(jìn)行脈沖標(biāo)記、定時(shí)取材、利用放射自顯影技術(shù)顯示標(biāo)記細(xì)胞，通過(guò)統(tǒng)計(jì)標(biāo)記有絲分裂細(xì)胞百分?jǐn)?shù)的辦法