This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Takamatsu, N Articles by Okada, Y Search for Related Content PubMed PubMed Citation Articles by Takamatsu, N Articles by Okada, Y

Mutational analysis of the pseudoknot region in the 3' noncoding region of tobacco mosaic virus RNA.

Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan.

ABSTRACT

The approximately 200-nucleotide-long 3'-terminal noncoding region of tobacco mosaic virus (TMV) RNA contains a tRNA-like structure and, in its immediate upstream region, three consecutive pseudoknots, each of which is composed of two double-helical segments. To elucidate the biological functions of the pseudoknot region, we constructed several deletion mutant TMV-L (a tomato strain) RNAs by using an in vitro transcription system and tested their ability to multiply in both tobacco plants and protoplasts. When deletions were introduced just downstream of the termination codon of the coat protein gene in the 5'-to-3' direction progressively, five of six double-helical segments were dispensable for viral multiplication, indicating that the pseudoknot structures are not essential for multiplication. However, extension of the deletion into the central pseudoknot region resulted in reduction in viral multiplication, accompanied by loss of development of mosaic symptoms on systemic tobacco plants. Cessation of multiplication was observed when the sequence involved in formation of double-helical segment I just upstream of the tRNA-like structure was deleted irrespective of the start point and extent of deletion. Point mutations that destabilized double-helical segment I resulted in a loss or great reduction of viral multiplication, whereas the double mutants in which the double helix was restored by additional compensating base substitutions restored multiplication to nearly the wild-type level. Thus, double-helical segment I just upstream of the tRNA-like structure is a structural feature essential for viral multiplication.

This article has been cited by other articles:

• Hirashima, K., Watanabe, Y. (2003). RNA Helicase Domain of Tobamovirus Replicase Executes Cell-to-Cell Movement Possibly through Collaboration with Its Nonconserved Region. J. Virol. 77: 12357-12362 [Abstract] [Full Text]  
• Osman, T. A. M., Buck, K. W. (2003). Identification of a Region of the Tobacco Mosaic Virus 126- and 183-Kilodalton Replication Proteins Which Binds Specifically to the Viral 3'-Terminal tRNA-Like Structure. J. Virol. 77: 8669-8675 [Abstract] [Full Text]  
• Zeenko, V. V., Ryabova, L. A., Spirin, A. S., Rothnie, H. M., Hess, D., Browning, K. S., Hohn, T. (2002). Eukaryotic Elongation Factor 1A Interacts with the Upstream Pseudoknot Domain in the 3' Untranslated Region of Tobacco Mosaic Virus RNA. J. Virol. 76: 5678-5691 [Abstract] [Full Text]  
• Osman, T. A. M., Hemenway, C. L., Buck, K. W. (2000). Role of the 3' tRNA-Like Structure in Tobacco Mosaic Virus Minus-Strand RNA Synthesis by the Viral RNA-Dependent RNA Polymerase In Vitro. J. Virol. 74: 11671-11680 [Abstract] [Full Text]  
• Watanabe, T., Honda, A., Iwata, A., Ueda, S., Hibi, T., Ishihama, A. (1999). Isolation from Tobacco Mosaic Virus-Infected Tobacco of a Solubilized Template-Specific RNA-Dependent RNA Polymerase Containing a 126K/183K Protein Heterodimer. J. Virol. 73: 2633-2640 [Abstract] [Full Text]  
• Benard, L., Mathy, N., Grunberg-Manago, M., Ehresmann, B., Ehresmann, C., Portier, C. (1998). Identification in a pseudoknot of a U·G motif essential for the regulation of the expression of ribosomal protein S15. Proc. Natl. Acad. Sci. USA 95: 2564-2567 [Abstract] [Full Text]  
• Nagy, P. D., Carpenter, C. D., Simon, A. E. (1997). A novel 3'-end repair mechanism in an RNA virus. Proc. Natl. Acad. Sci. USA 94: 1113-1118 [Abstract] [Full Text]