资源描述：
《Functional Expression》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、10356Biochemistry1991,30,10356-10361Switzer,C.,Moroney,S.E.,&Benner,S.A.(1989)J.Am.Ward,D.C.,&Reich,E.(1968)Proc.Natl.Acad.Sci.USA.Chem.SOC.111,8322-8323.61,1494-1501.Visser,C.M.,&Kellogg,R.M.(1978)J.Mol.Euol.11,Ward,D.C.,Cerami,A.,Reich,E.,Acs,G.,&Altwerger,171-187.L.(1969)J.Biol.Ch
2、em.244,3243-3250.vonKiedrowski,G.(1986)Angew.Chem.98,932-934.White,H.,111(1976)J.Mol.Evol.7,101-104.FunctionalExpressionandCharacterizationoftheInterferon-InducedDouble-StrandedRNAActivatedP68ProteinKinasefromEscherichiacoli?GlenN.Barber,$JudyTomha,$AraG.Hovanessian,*ElianeMews,*andM
3、ichaelG.Katze***DepartmentofMicrobiology,SchoolofMedicine,UniversityofWashington,Seattle,Washington98195,andUnit.?deVirologieandImmunologieCellulaire,InstitutPasteur,Paris,FranceReceivedJune4,1991;RevisedManuscriptReceivedJuly30,1991ABSTRACT:TheP68protein(referredtoasP68onthebasisofi
4、tsmolecularweightof68000inhumancells)isaserine/threoninekinaseinducedbyinterferontreatmentandactivatedbydouble-stranded(ds)RNAs.Althoughextensivelystudied,littleiscurrentlyknownabouttheregulationofkinasefunctionatthemolecularlevel.Whatisknownisthatactivationofthisenzymetriggersaserie
5、sofeventswhichleadtoaninhibitionofproteinsynthesisinitiationandmay,inturn,playanintegralroleintheantiviralresponsetointerferon.TobegintounderstandP68anditsbiologicalfunctionsintheeukaryoticcell,wehaveexpressedtheproteinkinaseinEscherichiacoliundercontrolofthebacteriophageT7promoter.I
6、nrifampicin-treatedcells,metabolicallylabeledwith[35S]methionineandinducedbyIPTG,theP68kinasewasthepredominantlabeledproduct.Further,P68wasrecoveredfromextractsasafullyfunctionalenzyme,shownbyitsabilitytobecomeactivatedandphosphorylateitsnaturalsubstrate,theCYsubunitofeukaryoticprote
7、insynthesisinitiationfactor2(eIF-2).Moreover,P68wasphosphorylatedinvivoinE.coli,providingconclusiveevidencethatthekinasehasthecapacitytophosphorylateandactivateitselfintheabsenceofothereukaryoticproteins.Incontrast,amutantP68protein,containingasingleaminoacidsubstitutionintheinvarian
8、tlysineincat
