©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http://www.cnki.netISSN100727626CN1123870ΠQ中国生物化学与分子生物学报ChineseJournalofBiochemistryandMolecularBiology2009年8月25(8):683~689·综述·核定位信号及其分析策略赵元茵1),王元忠1),曹念2),周度金1),李渝萍1)3(1)第三军医大学生物化学与分子生物学教研室,重庆400038;2)第三军医大学学员旅三队,重庆400038)摘要真核细胞核膜上的核孔复合体(nuclearporecomplex,NPC)是细胞核内外进行物质交换的主要通道,分子量较小的化合物可自由通过NPC或采取被动扩散的方式进入细胞核,而分子量为50kD以上的蛋白质则只能通过主动转运进入细胞核.以这种方式进入细胞核的蛋白质必须在其氨基酸序列上拥有特殊的核定位信号(nuclearlocalizationsignal,NLS),以被相应的核转运蛋白(karyopherins)识别.核定位信号具有多样性,包括经典核定位信号(classicalNLS,cNLS),内输蛋白β2识别的核定位信号(又称PY模体2NLS)和其它类型的NLS.每一类NLS具有相似的特征,但并不具有完全保守的氨基酸组成.不同的NLS,往往对应着各不相同的核输入机制.而对同一蛋白质来说,也可能同时拥有几个功能性的NLS.研究核定位信号一方面可以帮助揭示新的大分子物质核转运机制,另一方面也有助于发现一些蛋白质的新功能.本文对常见NLS的分类进行了总结,并介绍了两种常用的NLS预测软件及鉴定NLS的一般策略.关键词核转运机制;核定位信号;内输蛋白中图分类号Q291CategoriesandResearchStrategiesofNuclearLocalizationSignalZHAOYuan2Yin1),WANGYuan2Zhong1),CAONian2),ZHOUDu2Jin1),LIYu2Ping1)3(1)DepartmentofBiochemistryandMolecularBiology,ThirdMilitaryMedicalUniversity,Chongqing400038,China;2)Squadron3ofCadetBrigade,ThirdMilitaryMedicalUniversity,Chongqing400038,China)AbstractThenuclearporecomplex(NPC)isinchargeoftheexchangeofmacromoleculesbetweenthenucleiandthecytoplasmofeucaryoticcells.ThesmallcompoundscangetintothenucleithroughtheNPCfreelyorbypassivediffusion.However,thoseproteinswhosemolecularweightsarelargerthan50kDcanonlygetintonucleibyactivetransport.Theremustbeoneormorespecialsignalsintheaminoacidsequences,so2callednuclearlocalizationsignals,whichcanberecognizedbyrespectivekaryopherins,inthoseproteins.TherearediversesequencesinNLSs,includingclassicalNLS(cNLS),PY2NLS,whichcanberecognizedbyimportinβ2,andsomeotherNLSs.ThoughtherearesimilarpropertiesamongthesamefamilymembersofNLSs,thereisnofullyconservedaminoacidsequence.DifferentNLSsoftencorrespondtodifferentmechanismsofnucleartransport,andalso,coupleoffunctionalNLSsmayexistinonecertainprotein.ThestudiesonNLShelpusnotonlyrevealnewnucleartransportmechanismofmacromolecules,butalsodiscovernewfunctionsofproteins.CategoriesofNLSsweresummarizedbytheauthors.Twocommon2usedsoftwareemployedinNLSpredictionandthestrategiesusedtoidentifyNLSarealsointroducedinthisreview.Keywordsnucleartransportmechanism;nuclearlocalizationsignal;importin收稿日期:2009202217;接受日期:2009204213国家自然科学基金(No.30671056)、重庆市自然科学基金(No.2008BB5019)及第三军医大学“回国人员启动基金”资助(No.2008002)3联系人Tel:023268752940;E2mail:yupingli1999@yahoo.comReceived:February17,2009;Accepted:April13,2009SupportedbyNationalNaturalScienceFoundationofChina(No.30671056),NaturalScienceFoundationofChongqing(No.2008BB5019)andScientificResearchFoundationfortheReturnedOverseasScholarsofThirdMilitaryMedicalUniversity(No.2008002)3CorrespondingauthorTel:023268752940;E2mail:yupingli1999@yahoo.com©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http://www.cnki.net真核细胞的细胞核有核膜包被,核膜上的核孔复合体(nuclea...