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MEMBRANETRANSPORTMEMBRANETRANSPORT•••••••ABC•15~30%2/3•carrierproteinchannelprotein–carrierpermeasetransporterAPT–MembraneTransportProteins•freediffusion–––•PKD•P=KD/t•t•••H2OO2•••facilitateddiffusion••ionophore••–mobileioncarriervalinomycinK+DNPFCCPH+–channelformerAgranmicidin152H+Na+K+ValinomycinGramicidinAanantibioticthatactsasanionpore.channelprotein•••gatedchannel4IonChannelsIonChannels--------oror--------1(ligandgatedchannel)•“”••Ach452AchNicotinicacetylcholinereceptorThreeconformationoftheacetylcholinereceptor2(voltagegatedchannel)•“”•K+6(S1-S6)NCS5-S6(PH5)K+•K+S4•Na+K+Ca2+VoltagegatedK+channelKK++channelchannel4thsubunitnotshownIon-channellinkedreceptorsinneurotransmissionAchNa+K+Ca2+Ca2+3•CNG6C•CNG–GcAMPcAMPcAMP-gatedcationchannel4•mechanotransduction••21Na+K+Ca2+Ca2+5••1991AgreCHIP2828KDCHIP28mRNA5Hg2+•2003AgreMacKinnon•11AquaporinAQP2003··PeterAgreRoderickMacKinnon•–––•––ATPATP–•224Na+-K+ATP•–Na+-K+ATPNa+K+Na+ATPATPNa+Na+K+Na+K+K+K+K+K+Na+ATPNa+K+Na+-K+ATPPUMPNa+-K+ATPpumpcancatalyzetheformationofATPunderlaboratorycondition•ATPP-type•Na+-K+••Na+K+••Mg2+•10-7M10-3M••–PATP2Ca2+90%–Na+-Ca2+exchangerCaCa++++ATPaseATPaseMaintainslowcytosolic[Ca++]PresentInPlasmaandERmembranesModelformodeofactionforCa++ATPaseConformationchange•1P-typeATPH+H+-K+•2V-type(vacuole)ATP•3F-typeATPATPFourtypesofATP-poweredpumpsABC•ABCABCtransporterATPATPbindingcassetteABC•ABCABCMammalianMDR1proteinABCmultidrugresistanceprotein,MDR40%ABCcotransport••–Na+–H+•symportantiport•1symport•Na+H+•2antiport•Na+/H+H+PHNa+Cl--HCO3-Na+HCO3-Cl-H+3Glucoseisabsorbedbysymport•endocytosisexocytosiscytosis•••exocytosis•••–AIgA–••