期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1997
卷号：94
期号：21
页码：11238-11243
DOI：10.1073/pnas.94.21.11238
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：RNA templates of 33 nucleotides containing the brome mosaic virus (BMV) core subgenomic promoter were used to determine the promoter elements recognized by the BMV RNA-dependent RNA polymerase (RdRp) to initiate RNA synthesis. Nucleotides at positions -17, -14, -13, and -11 relative to the subgenomic initiation site must be maintained for interaction with the RdRp. Changes to every other nucleotide at these four positions allow predictions for the base-specific functional groups required for RdRp recognition. RdRp contact of the nucleotide at position -17 was suggested with a template competition assay. Comparison of the BMV subgenomic promoter to those from other plant and animal alphaviruses shows a remarkable degree of conservation of the nucleotides required for BMV subgenomic RNA synthesis. We show that the RdRp of the plant-infecting BMV is capable of accurately, albeit inefficiently, initiating RNA synthesis from the subgenomic promoter of the animal-infecting Semliki Forest virus. The sequence-specific recognition of RNA by the BMV RdRp is analogous to the recognition of DNA promoters by DNA-dependent RNA polymerases.
