The crystal structure of a Polerovirus exoribonuclease-resistant RNA shows how diverse sequences are integrated into a conserved fold
Year: 2020
Type: article
Abstract: Exoribonuclease-resistant RNAs (xrRNAs) are discrete elements that block the progression of 5' to 3' exoribonucleases using specifically folded RNA structures. A recently discovered class of xrRNA is widespread in several genera of plant-infecting viruses, within both noncoding and protein-coding subgenomic RNAs. The structure of one such xrRNA from a dianthovirus revealed three-dimensional details of the resistant fold but did not answer all questions regarding the conservation and diversity of this xrRNA class. Here, we present the crystal structure of a representative polerovirus xrRNA that contains sequence elements that diverge from the previously solved structure. This new structure rationalizes previously unexplained sequence conservation patterns and shows interactions not present in the first structure. Together, the structures of these xrRNAs from dianthovirus and polerovirus genera support the idea that these plant virus xrRNAs fold through a defined pathway that includes a programmed intermediate conformation. This work deepens our knowledge of the structure-function relationship of xrRNAs and shows how evolution can craft similar RNA folds from divergent sequences.
Source: RNA
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: bronze
Funders: U.S. Department of Energy, Deutsche Forschungsgemeinschaft, National Institutes of Health, Anschutz Medical Campus, University of Colorado, National Cancer Institute, National Institute of General Medical Sciences, National Institute of Allergy and Infectious Diseases, National Center for Research Resources
Awards: G1286236842, Macromolecular X-ray Data Collection Instrumentation, G3083819904, Automated Macromolecular Crystallization System, G3685081974, G382641700, G42916606, G6241773839, G9000054807, Structure, function, and dynamics of viral RNAs and RNA-containing complexes, ALS Efficiently Networking Advanced Beam Line Experiments (ALS-ENABLE), University of Colorado Cancer Center Support Grant, Mechanisms of viral RNA maturation by co-opting cellular exonucleases, G969889393
OpenAlex ID: W3080951784