title: Nucleoprotein phosphorylated on both serine and threonine is preferentially assembled into the nucleocapsids of measles virus.
abstract: The nucleoprotein (N) in the nucleocapsids of measles virus (MV) has different conformation and antigenicity than the free N-protein in MV-infected cells. These two forms of N-protein have identical methionine-containing tryptic peptides. The free N-protein contains 4 phosphorylated tryptic peptides. However, the nucleocapsid-associated N-protein has an additional phosphorylated peptide not found in the free N-protein. The free N-protein is phosphorylated only on serine residues, whereas the nucleocapsid-associated N-protein is phosphorylated on both serine and threonine residues. The MV N-protein expressed from a cloned gene in primate cells is also phosphorylated on both serine and threonine residues. These results suggest that cellular kinases phosphorylate the MV N-protein, and N-protein with phosphorylated serine and threonine is preferentially assembled into the viral nucleocapsids.
mesh_terms: D002478:Cells, Cultured; D006801:Humans; D019590:Nucleocapsid Proteins; D009698:Nucleoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D012694:Serine / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D014771:Virion / Q000378:metabolism
chemical_list: D019590:Nucleocapsid Proteins; D009698:Nucleoproteins; D014764:Viral Proteins; C058314:nucleoprotein, Measles virus; D013912:Threonine; D012694:Serine