Role of the 3′ tRNA-Like Structure in Tobacco Mosaic Virus Minus-Strand RNA Synthesis by the Viral RNA-Dependent RNA Polymerase In Vitro
AUTOR(ES)
Osman, T. A. M.
FONTE
American Society for Microbiology
RESUMO
A template-dependent RNA polymerase has been used to determine the sequence elements in the 3′ untranslated region of tobacco mosaic virus RNA that are required for promotion of minus-strand RNA synthesis and binding to the RNA polymerase in vitro. Regions which were important for minus-strand synthesis were domain D1, which is equivalent to a tRNA acceptor arm; domain D2, which is similar to a tRNA anticodon arm; an upstream domain, D3; and a central core, C, which connects domains D1, D2, and D3 and determines their relative orientations. Mutational analysis of the 3′-terminal 4 nucleotides of domain D1 indicated the importance of the 3′-terminal CA sequence for minus-strand synthesis, with the sequence CCCA or GGCA giving the highest transcriptional efficiency. Several double-helical regions, but not their sequences, which are essential for forming pseudoknot and/or stem-loop structures in domains D1, D2, and D3 and the central core, C, were shown to be required for high template efficiency. Also important were a bulge sequence in the D2 stem-loop and, to a lesser extent, a loop sequence in a hairpin structure in domain D1. The sequence of the 3′ untranslated region upstream of domain D3 was not required for minus-strand synthesis. Template-RNA polymerase binding competition experiments showed that the highest-affinity RNA polymerase binding element region lay within a region comprising domain D2 and the central core, C, but domains D1 and D3 also bound to the RNA polymerase with lower affinity.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=112449Documentos Relacionados
- The role of the pseudoknot at the 3' end of turnip yellow mosaic virus RNA in minus-strand synthesis by the viral RNA-dependent RNA polymerase.
- Minimal Template Requirements for Initiation of Minus-Strand Synthesis In Vitro by the RNA-Dependent RNA Polymerase of Turnip Yellow Mosaic Virus
- Initiation of minus-strand RNA synthesis by the brome mosaicvirus RNA-dependent RNA polymerase: use of oligoribonucleotide primers.
- Secondary Structure of the 3′ Terminus of Hepatitis C Virus Minus-Strand RNA
- Functional analysis of the tobacco mosaic virus tRNA-like structure in cytoplasmic gene regulation.
