Stimulation of Transcription by -Adenosyl--Homocysteine and Virion-encapsidated Methyl Donor in Spring Viraemia of Carp Virus Free

Abstract

Summary

-Adenosyl--methionine (SAM), a methyl donor, and its analogue -adenosyl--homocysteine (SAH), an inhibitor of methylation, stimulate the activity of spring viraemia of carp virus (SVCV) virion transcriptase. The stimulation observed for SVCV is analogous to that observed previously (Furuichi, 1974, 1978) for a totally unrelated virus, cytoplasmic polyhedrosis virus (CPV). In the absence of exogenous SAM, RNA with 5′-methylated termini (presumptive GpppAmpAp) was produced, indicating that SVCV has an endogenous methyl donor. Significantly less methylated termini were produced when SVCV nucleocapsids were used to prime transcription reactions, suggesting that the majority of the endogenous methyl donor is not associated with the nucleocapsid. Partial removal of endogenous methyl donor by preparing nucleocapsids did not have any effect on the degree of stimulation by exogenous SAM or SAH. We conclude from this study that SAH has two effects on SVCV transcription, inhibition of methylation and stimulation of transcription.

Loading

Article metrics loading...

/content/journal/jgv/10.1099/0022-1317-53-1-183
1981-03-01
2024-03-29
Loading full text...

Full text loading...

/deliver/fulltext/jgv/53/1/JV0530010183.html?itemId=/content/journal/jgv/10.1099/0022-1317-53-1-183&mimeType=html&fmt=ahah

References

  1. Bishop D. H. L. 1977; Virion polymerases. In Comprehensive Virology vol 10 pp 117–278 Edited by Fraenkel-Conrat H., Wagner R. R. New York: Plenum Press;
    [Google Scholar]
  2. Bishop D. H. L., Smith M. S. 1977; Rhabdoviruses. In Molecular Biology of Animal Viruses pp 167–180 Edited by Nayak D. New York: Marcel Dekker;
    [Google Scholar]
  3. Bishop D. H. L., Emerson S. U., Flamand A. 1974; Reconstitution of infectivity and transcriptase activity of homologous and heterologous viruses: vesicular stomatitis virus (Indiana serotype), Chandipura, vesicular stomatitis (New Jersey serotype), and cocal viruses. Journal of Virology 14:139–144
    [Google Scholar]
  4. Furuichi Y. 1974; Methylation-coupled transcription by virus-associated transcriptase of cytoplasmic polyhedrosis virus containing double-stranded RNA. Nucleic Acids Research 1:809–822
    [Google Scholar]
  5. Furuichi Y. 1978; ‘Pretranscriptional capping’ in the biosynthesis of cytoplasmic polyhedrosis virus mRNA. Proceedings of the National Academy of Sciences of the United States of America 75:1086–1090
    [Google Scholar]
  6. Gupta K. C., Roy P. 1980; Alternate capping mechanisms for transcription of spring viremia of carp virus: evidence of independent mRNA initiation. Journal of Virology 33:292–303
    [Google Scholar]
  7. Gupta K. C., Bishop D. H. L., Roy P. 1979; 5′-Terminal sequences of spring viremia of carp virus RNA synthesized in vitro. Journal of Virology 30:735–745
    [Google Scholar]
  8. Rose J. K., Lodish H. F., Brock M. L. 1977; Giant heterogeneous polyadenylic acid on vesicular stomatitis virus mRNA synthesized in vitro in the presence of S-adenosylhomocysteine. Journal of Virology 21:683–693
    [Google Scholar]
  9. Roy P., Clewley J. P. 1978; Spring viremia of carp virus RNA and virion-associated transcriptase activity. Journal of Virology 25:912–916
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jgv/10.1099/0022-1317-53-1-183
Loading
/content/journal/jgv/10.1099/0022-1317-53-1-183
Loading

Data & Media loading...

Most cited Most Cited RSS feed