蛋白質(zhì)分選下課件

Chapter7ProteinsortingII------free-ribosomesystemsecretorypathway

1.1SynthesisandTargetingofMitochondrial線粒體具有1000多種蛋白質(zhì)，其自身合成的僅十余種，因此大量蛋白質(zhì)是在細(xì)胞質(zhì)中合成的。MatrixOutermembraneIntermembranespaceCrosssectionofmitochondrionInnermembraneMitochondrialProteinsThatAreSynthesizedintheCytosolProteinsAreTargetedtoSub-mitochondrialCompartmentsProteinTransportintoInnerMembraneandIntermembraneSpaceRequiresTwoSignalSequences線粒體轉(zhuǎn)運(yùn)與葉綠體非常相似1.2SorttoChloroplastCompartmentImportofrubiscosmall(S)subunitsintothechloroplaststroma

轉(zhuǎn)運(yùn)肽內(nèi)囊體膜蛋白轉(zhuǎn)運(yùn)需要兩段信號(hào)1.3SynthesisandTargetingofPeroxisomeProteins

核基因合成，后轉(zhuǎn)運(yùn)方式運(yùn)輸1.4ProteinsorttonucleusThenuclearporecomplex0.1um

SideviewofnuclearporeMechanismofproteinimportProteinsselectedforimportintonucleushaveanuclearlocalizationsignal(NLS)e.g.-Pro-Pro-Lys-Lys-Lys-Arg-NLSisrecognizedbycytosolicnuclearimportreceptorswhichbindtonuclearporefibrilsextendingintocytosolPoreopensandproteinplusimportreceptorenternucleus.Importreceptorexportedforre-useNuclearlocalizationsignals

Nuclearlocalisationsignal(NLS)Nucleoplasminlabelandinjection

NucleoplasminlocationeffectProteintransportbynucleusporecomplexTransportisselectiveRestricttransportparticleRequireenergyexpendituresaturateddynamicTransportisdoubledirectionImportandexport1.4.2MechanismofexportfromnucleusMostoftrafficmovingoutofnucleusconsistsofdifferenttypesofRNAmoleculesRNAmovesthroughnuclearporeascomplexofribonucleoprotein(RNP):核糖核蛋白顆粒ProteincomponentofRNPcontainsanuclearexportsignal(NES)thatisrecognisedbyexportproteinsmRNAisboundbyhnRNPonlyafterfullysplicedsoonlymatureRNAisexportednuclearRNAandproteinexport

◆mRNAexport●核內(nèi)不均一核糖核蛋白(heterogeneousribonucleoprotein,hnRNP)●信使RNP(messengerRNP,mRNP