细胞间通讯和疾病培训.ppt

内容;第一部分细胞间通讯

的基本原理;一参与细胞间通讯的分子;;二细胞间通讯的类型;两种特殊的细胞间通讯

自分泌

间隙连接

通过间隙连接相连的细胞可进行水溶性小分子的交换，包括细胞内信号分子，从而使它们对细胞外信号作出一至反应;三细胞外的信号分子与受体结合;四受体;核受体

核受体家族是一类具有DNA结合结构域，在和信号分子结合后被激活，调节基因转录的蛋白质。

脂溶性的小分子细胞外信号分子通过扩散的方式进入细胞内与受体结合。这类信号分子包括类固醇、甲状腺激素、类视黄醇等。虽然这些分子在化学结构和功能上存在很大差异，但作用机制却相同。它们的受体都属于核受体家族，通过直接激活核受体调节基因的表达。

其他

如NO的受体是胞浆中的酶;五膜受体后信号的传递

（G蛋白偶联型受体和酶偶联型受体）;;Relayproteinssimplypassthemessagetothenextsignalingcomponentinthechain.

Messengerproteinscarrythesignalfromonepartofthecelltoanother,suchasfromthecytosoltothenucleus.

Adaptorproteinslinkonesignalingproteintoanother,withoutthemselvesconveyingasignal.

Amplifierproteins,whichareusuallyeitherenzymesorionchannels,greatlyincreasethesignaltheyreceive,eitherbyproducinglargeamountsofsmallintracellularmediatorsorbyactivatinglargenumbersofdownstreamintracellularsignalingproteins.Whentherearemultipleamplificationstepsinarelaychain,thechainisoftenreferredtoasasignalingcascade.

Transducerproteinsconvertthesignalintoadifferentform.TheenzymethatmakescyclicAMPisanexample:itbothconvertsthesignalandamplifiesit.Thusactingasbothatransducerandanamplifier.

Bifurcationproteinsspreadthesignalfromonesignalingpathwaytoanother.

Integratorproteinsreceivesignalsfromtwoormoresignalingpathwaysandintegratethembeforerelayingasignalonward.

Latentgeneregulatoryproteinsareactivatedatthecellsurfacebyactivatedbyreceptorsandthenmigratetothenucleustosimulategenetranscription.

Modulatorproteinsmodifyintracellularsignalingproteinsandtherebyregulatethestrengthofsignalingalongthepathway.

Anchoringproteinsmaintainspecificsignalingproteinatapreciselocationinthecellbytetheringthemtoamembraneorthecytoskeleton

.

Scaffoldproteinsareadaptorand/oranchoringproteinsthatbindmultiplesignalingproteinstogetherinafunctio