The duck hepatitis B virus core protein contains a highly phosphorylated C terminus that is essential for replication but not for RNA packaging.
AUTOR(ES)
Schlicht, H J
RESUMO
In this report, we present biochemical and mutational analyses of the duck hepatitis B virus core protein (DHBcAg). The data show that duck hepatitis B virus core particles consist of at least four different proteins with sizes between 32 and 34 kilodaltons, all of which react with DHBcAg-specific antiserum. Most of the heterogeneity was found to be due to extensive phosphorylation of the DHBcAg C terminus. Bacterially synthesized DHBcAg was not phosphorylated, and mutations within the viral P gene did not influence phosphorylation, suggesting that the kinase activity is not encoded by the viral C or P gene. Removal of the last 12 C-terminal DHBcAg amino acids, which are at least in part located on the core particle surface, had only a minor effect on DHBcAg phosphorylation and did not interfere with packaging of the capsids into viral envelopes or with genome replication. However, an attempt to infect ducklings with this mutant failed. Removal of the last 36 C-terminal DHBcAg amino acids abolished core protein heterogeneity but did not prevent particle formation. Interestingly, these particles were defective in genome replication, although they could still package viral pregenomic RNA.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=250854Documentos Relacionados
- Naturally occurring point mutation in the C terminus of the polymerase gene prevents duck hepatitis B virus RNA packaging.
- The duck hepatitis B virus pre-C region encodes a signal sequence which is essential for synthesis and secretion of processed core proteins but not for virus formation.
- The Duck Hepatitis B Virus Polymerase Is Activated by Its RNA Packaging Signal, ɛ
- The large surface protein of duck hepatitis B virus is phosphorylated in the pre-S domain.
- Coxsackie B3 virus protein 2B contains cationic amphipathic helix that is required for viral RNA replication.