细胞凋亡华子春课件

细胞凋亡与双语教学华子春医药生物技术国家重点实验室

南京大学《细胞生物学》课程双语课程介绍《细胞生物学》：专业必修课，2学时，本科生2年级《细胞生物学实验》：专业必修课，3学时，本科生2年级

《分子细胞生物学》：研究生选修课，4学时，研究生1年级

授课对象：生命科学学院、医学院、环境学院、强化部、物理系、生物制药（合办）专业

课程情况1．基础知识与学科发展相结合；2．细胞层次与其它微/宏观层次相结合；3.

细胞的结构与其功能相结合；4.

与普通生物学、生理学、分子生物学相结合、与生理和病理过程相结合；5．本专业知识与其它学科相结合：教学要点整体及生理、病理过程中的细胞结构与功能将基础理论知识与学科前沿发展相结合将分子细胞层次与病理生理过程相结合将夯实基本概念与培养创新意识相结合将国内教师主讲与外聘教师授课相结合教学理念寓学科前沿于基本理论之中寓实验原理于基本概念之中寓科学思维于基本概念之中中英文教学英文教学国内教师主讲外聘教师短期授课循序渐进、国际化和多元化的双语教学第1章：细胞概述（2学时）；第3章：细胞质膜与跨膜运输（3学时）；第4章：细胞环境与互作（3学时）；第5章：细胞通讯（6学时）；第6章：核糖体与核酶（2学时）；第7章：线粒体与过氧化物酶体（4学时）；第9章：内膜系统与蛋白质分选和膜运输（6学时）；第10章：细胞骨架与细胞运动（4学时）；第11章：细胞核与染色体（2学时）；第12章：细胞周期与细胞分裂（4学时）；第13和:细胞死亡（2学时）。课时安排第十三章细胞死亡

—基础概念与实际应用

ApoptosisvsnecrosisApoptosisNecrosisDeathbyapoptosisisaneat,orderlyprocessNecrosis

•Deathbyaccident•Associatedwithnonphysiologicalcircumstancesthatdisruptcellularhomeostasis(eg.,ischemia,hypoxiaandpoisoning)•Necrosisiscausedbymembranedissolution(osmoticlysis,shearstress,pore-formingproteins,lossofATP)•Necrosisisbadbecausecellularmaterial(includingdegradativeenzymes)isreleasedintosurroundingtissue•Affectscontiguousgroupsofcell•NecrosisusuallycausesinflammatoryreactionCytologicalcharacteristicsofnecrosis•Initialswellingofthecell•Ruptureoftheplasmamembrane•CytoplasmisspilledtotheextracellularenvironmentApoptosis

•Deathbydesign–geneticallyprogrammedcelldeath•Inducedbynewgenesynthesis,primarilyinresponsetodevelopmentalcues•RequiresnewRNAandproteinsynthesis–Inhibitorsoftranscriptionortranslationpreventapoptosis•Importantfordevelopment,homeostasisandeliminationofpathogensandtumorcells•Causesdeletionofindividualcellsinthemidstofothers–Butitcanbeinvolvedindeletionofentirestructures•Apoptosisisfollowedbyfastphagocytosis–Anti-inflammatory(housekeeping)Morphologicchangesduringapoptosis

•Membranesbecomeirregular•Chromatinbecomescondensedandsegregated•Condensationofcytoplasm•DNAisfragmented•CellisfragmentedandphagocytosedBiochemicalcharacteristicsofapoptosis:ApoptosisinducedbyCytoCLane1．0h2．1h3．2h4．3h5．4h6．Control7．Marker

2.0kbp1.00.50.2180~200bpDNAladder,AccumulationoftTG,PSflip-flop体内细胞凋亡检测紫杉醇治疗小鼠肺癌肿瘤ApoptosisDoesNotDamageNeighboringCellsMorphologicalfeaturesofapoptosis:CytoskeletoncollapsesNuclearenvelopedisassemblesNuclearDNAbreaksupintofragmentsCellsurfacechangessothatthecellcanberapidlyphagocytosedTheconsequenceisneatdeath---nodamagetotheneighboringcellsDeathbycellnecrosis;cellcontentsspilledallovertheneighborsCellapoptosis,inculturedishCellapoptosis,intissue.ShowingphagocytosisFormsofcelldeathNecrosisApoptosisPassiveActivePathologicalPhysiologicalor pathologicalSwelling,lysis Condensation,cross-linkingDissipatesPhagocytosedInflammation NoinflammationExternallyinduced Internallyor externallyinducedAPOPTOSISProgrammedcelldeathOrderlycellularselfdestructionProcess:ascrucialforsurvivalofmulti-cellularorganismsascelldivisionMULTIPLEFORMS???ApoptosispathwaysAPOPTOSIS:importantinembryogenesis•Intrinsic/MitochondrialApoptosis–RegulatedbyMitochondria–Cytochromecrelease•Extrinsic/DeathReceptorApoptosis–ActivatedbyligationofDeathReceptors–Fas,TNFalpha•ThesepathwaysintersectattheeffectorcaspasesTwoPathwaysthatInitiateApoptosis

APOPTOSIS:controlReceptorpathway(physiological):Deathreceptors:(FAS,TNF-R,etc)FASligandTNFDeathdomainsAdaptorproteinsPro-caspase8(inactive)Caspase8(active)Pro-executioncaspase(inactive)Executioncaspase(active)DeathMITOCHONDRIAAPOPTOSIS:control

PhysiologicalIntrinsicreceptorpathwaydamagepathwayMITOCHONDRIALSIGNALSCaspasecleavagecascadeOrderlycleavageofproteinsandDNACROSSLINKINGOFCELLCORPSES;ENGULFMENT(noinflammation)ApoptosisIsMediatedbyaCaspasesApoptosisdependsonagroupofproteases---Caspases(胱冬蛋白酶)Havea

cysteine

(半胱氨酸)intheactivesiteCleavethetargetproteinsatspecificasparticacid

(天冬氨酸)residuesCaspasesaresynthesizedasinactiveprocursor,“procaspase”.Othercaspasesactivateitbycleavingit:Aapoptoticproteolyticsystem—caspase

Whycalledcaspase?Activesite:CysteineCleavagesite:Asparaticacid

CysteineAsparaticacidspecificproteaseAps-Xxx天冬氨酸特异性的半胱氨酸蛋白水解酶CaspasesTriggeraProteolysisCascadeCleavesinhibitorsofDNaseDNAfragmentationAPOPTOSIS:RoleinDiseaseCancerApoptosiseliminatesdamagedcells(damage=>mutations=>cancer)Tumorsuppressorp53controlssenescenceandapoptosisresponsestodamageMostcancercellsaredefectiveinapoptoticresponse(damaged,mutantcellssurvive)Highlevelsofanti-apoptoticproteinsorLowlevelsofpro-apoptoticproteins===>CANCERTRAIL:

一种细胞凋亡诱导蛋白质TRAIL:肿瘤坏死因子相关的凋亡诱导配体TRAIL肿瘤选择性:不同TRAIL受体表达的结果死亡受体(DR4，DR5):

介导细胞凋亡信号诱骗受体(DcR1，DcR2):不传导细胞凋亡信号DcRs与DRs

竞争结合TRAIL，赋予正常组织TRAIL抗性TRAIL变体具有更好的细胞凋亡活性

Adaptorproteinsbringmanycopiesofinitiatorprocaspase

togetherInitiatorcaspasehaslowactivity,butwhentheyformaggregates,theycancross-activateeachother.AggregationcausesconformationalchangesApoptosisIsActivatedbyBindingtoAdaptorProteinstoFormAggregatesFasFasLFADDCaspase

8APOPTOSISActivationofApoptosisfromOutsidetheCellDeathreceptorsKillerlymphocytesproduceFas

ligandtobindtoFasprotein(deathreceptor)ontargetcellsAdaptorproteinsaggregate

caspase8,whichcross-activateSomedamagedcellsproducebothFasligandandFasproteinforself-destructionExtrinsicpathwayAPOPTOSIS:controlIntrinsicpathway(damage):MitochondriaCytochromecreleasePro-caspase9cleavagePro-executioncaspase(3)cleavageCaspase(3)cleavageofcellularproteins,nucleaseactivation,etc.DeathBAXBAKBOKBCL-XsBADBIDBIKBIMNIP3BNIP3BCL-2BCL-XLBCL-WMCL1BFL1DIVANR-13SeveralviralproteinsActivationofApoptosisfromInsidetheCellIntrinsicpathwayWhencellsaredamaged:Mitochondriareleasecytochromec

Incytosol,cytochromecbindstoApaf-1

(adaptorprot