The Phosphorylation of NS Protein of Wheat Rosette Stunt Virus

XIE Bao-Tong, YE Yong-Jun, GONG Zu-Xun*

( Key Laboratory of Proteomics, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031, China )

Abstract The genome of wheat rosette stunt virus (WRSV), a plant rhabdovirus, is a single negative strand RNA. It encodes five viral structural proteins: the glycoprotein (G), the matrix protein (M), the nucleocapsid protein (N), the large protein (L) and the non-structural protein (NS), which was later proved to be a viral structural protein too and existed in a variety of phosphorylation forms in case of vascular stomatitis virus (VSV). In this paper we demonstrated that NS protein of WRSV, either bound with the viral nucleocapsid or expressed in bacteria could be in vitro phosphorylated in presence of viral nucleocapsid. We concluded that the NS protein of WRSV was a phosphorylated protein and it might exist in both phosphorylated and dephosphorylated forms in virions. Our results excluded the possibility that the NS protein could be autophosphorylated. The L protein, the major component of viral RNA dependent RNA polymerase is associated with the protein kinase for phosphorylation of NS protein.

Key words wheat rosette stunt virus; NS protein; phosphorylation; protein kinase

*Corresponding author: Tel, 86-21-54921220; Fax, 86-21-54921125; e-mail, [email protected]