BackgroundInformation | S-100proteinisamemberoftheEF-handcalcium-bindingproteinsuperfamilythatiswidelydistributedandconservedinthecentralnervoussystemofvertebrates.Theproteinexistsinbothheterodimericandhomodimericforms.ThetwosubunitsofS-100proteinaretheproductsofseparategenesthataredifferentiallyexpressedbyvariouscells.ThebetasubunitispresentinallS-100positivecellsandtumors.Incontrast,thealphasubunitisdetectableonlyinheart,skeletalmuscleandbrain.Inadditiontoitscalciumbindingproperties,S-100proteinhasahigh-affinitybindingsiteforzincandisinvolvedintheregulationofproteinphosphorylationinthebrain.Theproteinapparentlyplaysaroleincelldifferentiationandgrowth,cytoskeletalstructureandfunction,andhasbeenimplicatedinneuropathologicaldiseases. |