The L protein of Rift Valley fever virus can rescue viral ribonucleoproteins and transcribe synthetic genome-like RNA molecules - PubMed (original) (raw)

The L protein of Rift Valley fever virus can rescue viral ribonucleoproteins and transcribe synthetic genome-like RNA molecules

N Lopez et al. J Virol. 1995 Jul.

Abstract

Overlapping cDNAs representing the complete L segment of Rift Valley fever virus were assembled, and the L protein was expressed via a recombinant vaccinia virus. The transcriptase activity of the L protein was assayed with two types of templates: natural ribonucleoproteins (RNPs) and artificial genome-like RNAs. RNPs purified in a CsCl gradient did not retain the RNA polymerase function, but the activity was restored when the L cDNA was expressed in mammalian cells via a recombinant vaccinia virus. Indeed, after transfection of transcriptase-depleted RNPs in cells infected with the recombinant vaccinia virus expressing the L protein, the mRNAs coding for the N and NSs proteins and to a lesser extent, those coding for the glycoproteins were synthesized as well as the corresponding proteins. The transcriptase activity of the recombinant L protein was then investigated by using synthetic templates containing the reporter chloramphenicol acetyltransferase gene in the antisense orientation flanked by the 3' and 5' noncoding region of the S genomic segment. Our results indicate that after transfection of the RNA templates, transcription was achieved in cells coexpressing both the L and N proteins. Together, the experiments demonstrate that the two proteins N and L are absolutely required and sufficient to reconstitute the transcriptase activity.

PubMed Disclaimer

References

1. J Virol. 1972 Aug;10(2):297-309 - PubMed
1. J Gen Virol. 1991 Sep;72 ( Pt 9):2207-16 - PubMed
1. J Gen Virol. 1985 Oct;66 ( Pt 10):2271-7 - PubMed
1. Virology. 1985 Jul 15;144(1):228-45 - PubMed
1. Proc Natl Acad Sci U S A. 1986 Nov;83(21):8122-6 - PubMed

The L protein of Rift Valley fever virus can rescue viral ribonucleoproteins and transcribe synthetic genome-like RNA molecules - PubMed (original) (raw)