简介：TheCoronaviridaefamilyischaracterizedbyanucleocapsidthatiscomposedofthegenomeRNAmoleculeincombinationwiththenucleoprotein(Nprotein)withinavirion.ThemoststrikingphysiochemicalfeatureoftheNproteinofSARS-CoVisthatitisatypicalbasicproteinwithahighpredictedpIandhighhydrophilicity,whichisconsistentwithitsfunctionofbindingtotheribophosphatebackboneoftheRNAmolecule.ThepredictedhighextentofphosphorylationoftheNproteinonmultiplecandidatephosphorylationsitesdemonstratesthatitwouldberelatedtoimportantfunctions,suchasRNA-bindingandlocalizationtothenucleolusofhostcells.SubsequentstudyshowsthatthereisanSR-richregionintheNproteinandthisregionmightbeinvolvedintheprotein-proteininteraction.TheabundantantigenicsitespredictedintheNprotein,aswellasexperimentalevidencewithsynthesizedpolypeptides,indicatethattheNproteinisoneofthemajorantigensoftheSARS-CoV.Comparedwithotherviralstructuralproteins,thelowvariationrateoftheNproteinwithregardstoitssizesuggestsitsimportancetothesurvivalofthevirus.