Effect of core protein phosphorylation by protein kinase C on encapsidation of RNA within core particles of hepatitis B virus.
AUTOR(ES)
Kann, M
RESUMO
Phosphorylation of core particles derived either from hepatitis B viruses or from livers of hepatitis B-infected individuals has been long recognized, but the nature and function of the phosphorylating enzyme remained unknown. By immunoblotting with a monoclonal antibody, we have now detected protein kinase C within the liver-derived core particles. To study the significance of the encapsidated protein kinase C for the viral life cycle, we established an in vitro assembly system consisting of Escherichia coli-expressed core protein, protein kinase C, and in vitro-synthesized hepatitis B virus RNA. Phosphorylation of the core protein led to a reduced RNA encapsidation capacity of the core particles. Furthermore, RNA and protein kinase C competed for their target sequence, which is the carboxy-terminal arginine-rich domain of the core protein. This finding implies that phosphorylation of the nucleic acid binding site in the core protein occurs within the particles after encapsidation of protein kinase C, pregenomic RNA, and viral polymerase at a later step during viral genome maturation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=237262Documentos Relacionados
- Core particles of hepatitis B virus and ground squirrel hepatitis virus. II. Characterization of the protein kinase reaction associated with ground squirrel hepatitis virus and hepatitis B virus.
- Chimeric hepatitis B virus core particles with parts or copies of the hepatitis C virus core protein.
- Phosphorylation of the Core Protein of Hepatitis B Virus by a 46-Kilodalton Serine Kinase
- Core Protein Phosphorylation Modulates Pregenomic RNA Encapsidation to Different Extents in Human and Duck Hepatitis B Viruses
- Insertions within the hepatitis B virus capsid protein influence capsid formation and RNA encapsidation.