Thep44/42MAPKinasepathwayconsistsofaproteinkinasecascadelinkinggrowthanddifferentiationsignalswithtranscriptioninthenucleus.GrowthfactorreceptorsandtyrosinekinasesactivateRaswhichinturnactivatesc-Raf,MEK,andMAPkinase.Activatedp44/42MAPKinasetranslocatestothenucleusandactivatestranscriptionbyphosphorylationofkinasessuchasp90RSK,MSK,andtranscriptionfactorssuchasELK-1andStat3.TheimportanceofthispathwayinbothgrowthcontrolanddevelopmenthasbeendemonstratedviathetransformingpropertiesofvariousmutantformsofRas,Raf,MEKandbytheireffectsondevelopment.Signalamplificationandthepotentialforcrosstalkappeartobeimportantfeaturesofthisregulatorynetwork. Contributor:CellSignalingTechnology REFERENCES: