BackgroundInformation | TestPrinciple TheUPSTATE®colorimetricSTAR(SignalTransductionAssayReaction)ELISAkitisasolidphasesandwichenzymelinkedimmunosorbentassaythatprovidesafast,sensitivemethodtodetectspecificlevelsofsignalingtargetsinwholecellextracts.TheIkBplateiscoatedwithaspecificmousemonoclonalIkBcaptureantibodyonthemicrowellsofthe96-wellclearplate.SamplelysateorthestandardincludedinthekitareincubatedinthemicrowellsallowingIkBantigentobecapturedintheplatewells.Theplateisthenwashedtoremoveanynon-boundunspecificmaterial.Thewellsarethenincubatedwithaspecificrabbitanti-IkBantibodytodetectthecaptureIkBontheplatewell.TheunbounddetectionantibodyiswashedawayfollowedbyincubationwithanHRP-conjugatedanti-rabbitantibody.Thisallowsforasensitiveenzymaticdetectionofthesample.AftertheadditionofTMBsubstrateandstopsolutiontheabsorbanceismeasuredat450nmusingaplatereader. Theentireassaytakeslessthan5hourstocompletewithminimalhands-ontime.Manyofthereagentsaresuppliedinready-touseformulationsforeaseofuse.Thekitalsoincludesastandardthatisrunasbothapositivecontrolandtodevelopastandardlineofdetection.
IkBBackground IKKbeta(IkBKinase,IKKb,I-Kappa-Bkinase-beta)isamemberoftheIKKcomplexwhichiscomposedofIKKalpha,IKKbeta,IKKgammaandIKAP.IkBKinase(IKK)complexisacriticalcomponentinNFBregulation.Inamajorityofunstimulatedcells,theNFκBtranscriptionfactorsexistintheirinactiveformandareretainedinthecytoplasmbytheboundinhibitoryIkBproteins.ForNFBtobecomeactivated,itmustfirstdisassociatefromtheinhibitorIκB.ThisoccursviatheserinephosphorylationofIkBonSer32andSer36.Postreceptorstimulation,mostnotablybyTNFα,NIK,aserine/threoninekinase,becomesactivatesandphosphorylatesIKKαandIKKβ.Phosphorylationof2sitesattheactivationloopofIKKbetaisessentialforactivationofIKKbyTNFandIL1.Onceactivated,IKKbetaautophosphorylates,whichinturndecreasesIKKactivityandpreventsprolongedactivationoftheinflammatoryresponse.Additionally,IKKbetaactivitycanalsoberegulatedbyMEKK-1.IKKthenbindstoandphosphorylatesIkBαonthetwoserineresidues.ThisphosphorylationmarksIkBforubiquinationanddestructionbytheproteosome.ThisfreetheNFkBcomplexandallowsittotranslocatestothenucleus. |