Abstract
Preceding and following each gene of respiratory syncytial virus (RSV) are two conserved sequences, the gene-start (GS) and gene-end (GE) motifs, respectively, which are thought to be transcription signals. The functions and boundaries of these signals and the process of sequential transcription were analyzed with cDNA-encoded RNA analogs (minigenomes) of nonsegmented negative-sense RSV genomic RNA. Two minigenomes were used. The monocistronic RSV-CAT minigenome consists of the chloramphenicol acetyltransferase (CAT) translational open reading frame (ORF) bordered by the GS and GE motifs and flanked by the 3' leader and 5' trailer extragenic regions of genomic RNA. The dicistronic RSV-CAT-LUC minigenome is a derivative of RSV-CAT into which the ORF for luciferase (LUC), bordered by GS and GE motifs, was inserted downstream of the CAT gene with an intergenic region positioned between the two genes. Each minigenome was synthesized in vitro and transfected into RSV-infected cells, where it was replicated and transcribed to yield the predicted polyadenylated subgenomic mRNA(s). The only RSV sequences required for efficient transcription and RNA replication were the 44-nucleotide 3' leader region, the last 40 nucleotides of the 5' trailer region, and the 9- to 10-nucleotide GS and 12- to 13-nucleotide GE motifs. The GS and GE motifs functioned as self-contained, transportable transcription signals which could be attached to foreign sequences to direct their transcription into subgenomic mRNAs. Removal of the GS motif greatly reduced transcription of its gene, and the requirement for this element was particularly strict for the gene in the downstream position. Ablation of the promoter-proximal GS signal was not associated with increased antigenome synthesis. Consistent with its proposed role in termination and polyadenylation, removal of the CAT GE signal in RSV-CAT resulted in the synthesis of a nonpolyadenylated CAT mRNA, and in RSV-CAT-LUC the same mutation resulted in readthrough transcription to yield a dicistronic CAT-LUC mRNA. The latter result showed that a downstream GS signal is not recognized for reinitiation by the polymerase if it is already engaged in mRNA synthesis; instead, it is recognized only if the polymerase first terminates transcription at an upstream termination signal. This result also showed that ongoing transcription did not open the downstream LUC gene for internal polymerase entry. Removal of both the GS and GE signals of the upstream CAT gene in RSV-CAT-LUC silenced expression of both genes, confirming that independent polymerase entry at an internal gene is insignificant. Remarkably, whereas both genes were silent when the CAT GS and GE signals were both absent, restoration of the CAT GE signal alone restored a significant level (approximately 10 to 12% of the wild-type level) of synthesis of both subgenomic mRNAs. This analysis identified a component of sequential transcription that was independent of the promoter-proximal GS signal and appeared to involve readthrough from the leader region.
Full Text
The Full Text of this article is available as a PDF (473.8 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Ball L. A., White C. N. Order of transcription of genes of vesicular stomatitis virus. Proc Natl Acad Sci U S A. 1976 Feb;73(2):442–446. doi: 10.1073/pnas.73.2.442. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Castaneda S. J., Wong T. C. Leader sequence distinguishes between translatable and encapsidated measles virus RNAs. J Virol. 1990 Jan;64(1):222–230. doi: 10.1128/jvi.64.1.222-230.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Castaneda S. J., Wong T. C. Measles virus synthesizes both leaderless and leader-containing polyadenylated RNAs in vivo. J Virol. 1989 Jul;63(7):2977–2986. doi: 10.1128/jvi.63.7.2977-2986.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chomczynski P. One-hour downward alkaline capillary transfer for blotting of DNA and RNA. Anal Biochem. 1992 Feb 14;201(1):134–139. doi: 10.1016/0003-2697(92)90185-a. [DOI] [PubMed] [Google Scholar]
- Collins P. L., Dickens L. E., Buckler-White A., Olmsted R. A., Spriggs M. K., Camargo E., Coelingh K. V. Nucleotide sequences for the gene junctions of human respiratory syncytial virus reveal distinctive features of intergenic structure and gene order. Proc Natl Acad Sci U S A. 1986 Jul;83(13):4594–4598. doi: 10.1073/pnas.83.13.4594. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Collins P. L., Mink M. A., Stec D. S. Rescue of synthetic analogs of respiratory syncytial virus genomic RNA and effect of truncations and mutations on the expression of a foreign reporter gene. Proc Natl Acad Sci U S A. 1991 Nov 1;88(21):9663–9667. doi: 10.1073/pnas.88.21.9663. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Collins P. L., Olmsted R. A., Spriggs M. K., Johnson P. R., Buckler-White A. J. Gene overlap and site-specific attenuation of transcription of the viral polymerase L gene of human respiratory syncytial virus. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5134–5138. doi: 10.1073/pnas.84.15.5134. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Collins P. L., Wertz G. W. Nucleotide sequences of the 1B and 1C nonstructural protein mRNAs of human respiratory syncytial virus. Virology. 1985 Jun;143(2):442–451. doi: 10.1016/0042-6822(85)90384-8. [DOI] [PubMed] [Google Scholar]
- Crowley J. C., Dowling P. C., Menonna J., Silverman J. I., Schuback D., Cook S. D., Blumberg B. M. Sequence variability and function of measles virus 3' and 5' ends and intercistronic regions. Virology. 1988 Jun;164(2):498–506. doi: 10.1016/0042-6822(88)90564-8. [DOI] [PubMed] [Google Scholar]
- Dickens L. E., Collins P. L., Wertz G. W. Transcriptional mapping of human respiratory syncytial virus. J Virol. 1984 Nov;52(2):364–369. doi: 10.1128/jvi.52.2.364-369.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Emerson S. U. Reconstitution studies detect a single polymerase entry site on the vesicular stomatitis virus genome. Cell. 1982 Dec;31(3 Pt 2):635–642. doi: 10.1016/0092-8674(82)90319-1. [DOI] [PubMed] [Google Scholar]
- Gorman C. M., Moffat L. F., Howard B. H. Recombinant genomes which express chloramphenicol acetyltransferase in mammalian cells. Mol Cell Biol. 1982 Sep;2(9):1044–1051. doi: 10.1128/mcb.2.9.1044. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grosfeld H., Hill M. G., Collins P. L. RNA replication by respiratory syncytial virus (RSV) is directed by the N, P, and L proteins; transcription also occurs under these conditions but requires RSV superinfection for efficient synthesis of full-length mRNA. J Virol. 1995 Sep;69(9):5677–5686. doi: 10.1128/jvi.69.9.5677-5686.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gupta K. C., Kingsbury D. W. Polytranscripts of Sendai virus do not contain intervening polyadenylate sequences. Virology. 1985 Feb;141(1):102–109. doi: 10.1016/0042-6822(85)90186-2. [DOI] [PubMed] [Google Scholar]
- Huang Y. T., Wertz G. W. The genome of respiratory syncytial virus is a negative-stranded RNA that codes for at least seven mRNA species. J Virol. 1982 Jul;43(1):150–157. doi: 10.1128/jvi.43.1.150-157.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Iverson L. E., Rose J. K. Localized attenuation and discontinuous synthesis during vesicular stomatitis virus transcription. Cell. 1981 Feb;23(2):477–484. doi: 10.1016/0092-8674(81)90143-4. [DOI] [PubMed] [Google Scholar]
- Kunkel T. A., Roberts J. D., Zakour R. A. Rapid and efficient site-specific mutagenesis without phenotypic selection. Methods Enzymol. 1987;154:367–382. doi: 10.1016/0076-6879(87)54085-x. [DOI] [PubMed] [Google Scholar]
- Kuo L., Fearns R., Collins P. L. The structurally diverse intergenic regions of respiratory syncytial virus do not modulate sequential transcription by a dicistronic minigenome. J Virol. 1996 Sep;70(9):6143–6150. doi: 10.1128/jvi.70.9.6143-6150.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Masters P. S., Samuel C. E. Detection of in vivo synthesis of polycistronic mRNAs of vesicular stomatitis virus. Virology. 1984 Apr 30;134(2):277–286. doi: 10.1016/0042-6822(84)90297-6. [DOI] [PubMed] [Google Scholar]
- McMaster G. K., Carmichael G. G. Analysis of single- and double-stranded nucleic acids on polyacrylamide and agarose gels by using glyoxal and acridine orange. Proc Natl Acad Sci U S A. 1977 Nov;74(11):4835–4838. doi: 10.1073/pnas.74.11.4835. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Perrault J., Clinton G. M., McClure M. A. RNP template of vesicular stomatitis virus regulates transcription and replication functions. Cell. 1983 Nov;35(1):175–185. doi: 10.1016/0092-8674(83)90220-9. [DOI] [PubMed] [Google Scholar]
- Rose J. K. Complete intergenic and flanking gene sequences from the genome of vesicular stomatitis virus. Cell. 1980 Feb;19(2):415–421. doi: 10.1016/0092-8674(80)90515-2. [DOI] [PubMed] [Google Scholar]
- Samal S. K., Collins P. L. RNA replication by a respiratory syncytial virus RNA analog does not obey the rule of six and retains a nonviral trinucleotide extension at the leader end. J Virol. 1996 Aug;70(8):5075–5082. doi: 10.1128/jvi.70.8.5075-5082.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schneemann A., Schneider P. A., Kim S., Lipkin W. I. Identification of signal sequences that control transcription of borna disease virus, a nonsegmented, negative-strand RNA virus. J Virol. 1994 Oct;68(10):6514–6522. doi: 10.1128/jvi.68.10.6514-6522.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spriggs M. K., Collins P. L. Human parainfluenza virus type 3: messenger RNAs, polypeptide coding assignments, intergenic sequences, and genetic map. J Virol. 1986 Sep;59(3):646–654. doi: 10.1128/jvi.59.3.646-654.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Takeuchi K., Tanabayashi K., Hishiyama M., Yamada A., Sugiura A. Variations of nucleotide sequences and transcription of the SH gene among mumps virus strains. Virology. 1991 Mar;181(1):364–366. doi: 10.1016/0042-6822(91)90504-5. [DOI] [PubMed] [Google Scholar]
- Testa D., Chanda P. K., Banerjee A. K. Unique mode of transcription in vitro by Vesicular stomatitis virus. Cell. 1980 Aug;21(1):267–275. doi: 10.1016/0092-8674(80)90134-8. [DOI] [PubMed] [Google Scholar]
- Tsurudome M., Bando H., Kawano M., Matsumura H., Komada H., Nishio M., Ito Y. Transcripts of simian virus 41 (SV41) matrix gene are exclusively dicistronic with the fusion gene which is also transcribed as a monocistron. Virology. 1991 Sep;184(1):93–100. doi: 10.1016/0042-6822(91)90825-v. [DOI] [PubMed] [Google Scholar]
- Vidal S., Kolakofsky D. Modified model for the switch from Sendai virus transcription to replication. J Virol. 1989 May;63(5):1951–1958. doi: 10.1128/jvi.63.5.1951-1958.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wertz G. W., Whelan S., LeGrone A., Ball L. A. Extent of terminal complementarity modulates the balance between transcription and replication of vesicular stomatitis virus RNA. Proc Natl Acad Sci U S A. 1994 Aug 30;91(18):8587–8591. doi: 10.1073/pnas.91.18.8587. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yu Q., Hardy R. W., Wertz G. W. Functional cDNA clones of the human respiratory syncytial (RS) virus N, P, and L proteins support replication of RS virus genomic RNA analogs and define minimal trans-acting requirements for RNA replication. J Virol. 1995 Apr;69(4):2412–2419. doi: 10.1128/jvi.69.4.2412-2419.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]