RNA viruses can exploit self-cleaving ribozymes for translation initiation
8 affiliations
- 1Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-CSIC , E-46022, Valencia ,
- 2Graduate School of Bioagricultural Sciences, Nagoya University , JP-464-8601, Chikusa, Nagoya ,
- 3Institute for Sustainable Plant Protection, National Research Council of Italy , I-10135, Torino ,
- 4Institute for Sustainable Plant Protection, National Research Council of Italy , I-70126, Bari ,
- 5Department of Molecular Genetics, University of Toronto , CA-M5S 1A8, Toronto, ON ,
- 6Terrence Donnelly Centre for Cellular & Biomolecular Research, University of Toronto , CA-M5S 3E1, Toronto, ON ,
- 7Institute for Sustainable Plant Protection, National Research Council of Italy , I-25123, Brescia ,
- 8Department of Plant Protection, School of Agriculture, The University of Jordan , JO-11942, Amman ,
Abstract
Small self-cleaving ribozymes are catalytic RNAs discovered in viroid-like agents, which are replicating circular RNAs (circRNAs) postulated as relics of a prebiotic RNA world. In the last decade, however, small ribozymes have also been detected across the tree of life, from bacterial to human genomes, and more recently, in unusual circRNA viruses. Here we report the conserved occurrence of diverse small ribozymes within the linear genomes of typical single- and double-stranded RNA viruses infecting fungi and plants. We identified type I hammerhead ribozymes in the 5'-UTRs of chrysovirids and fusarivirids, displaying self-cleaving activity in vitro and in vivo. Similar hammerhead, as well as hepatitis delta and twister ribozymes, occur in diverse megabirna-, hypo-, fusagra-, toti-, or tombus-like viruses. The ribozymes appear as isolated motifs within the UTRs or as tandem pairs that encompass small RNA segments (186-399 nt) resembling Zetavirus-like sequences. In vivo characterization of the 5'-UTR from a fungal chrysovirus revealed that its RNA self-cleaving activity is essential for protein translation initiation. Analogous experiments in plants with diverse ribozyme motifs confirmed that self-cleaving activity alone can induce cap-independent translation. We conclude that RNA self-cleaving activity, historically linked to the rolling circle replication of viroid-like circRNAs, appears to be co-opted by some linear RNA viruses for translational roles.
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BibTeX
@article{lopezgaliano2026viruses,
title = {{RNA viruses can exploit self-cleaving ribozymes for translation initiation}},
author = {María José López-Galiano and Olga Rueda and Sotaro Chiba and Marco Forgia and Beatriz Navarro and Amelia Cervera and Artem Babaian and Francesco Di Serio and Massimo Turina and Marcos de la Peña},
journal = {Nucleic Acids Research},
year = {2026},
month = oct,
doi = {10.1093/nar/gkag1106},
url = {https://academic.oup.com/nar/article/doi/10.1093/nar/gkag1106/9006196},
note = {CC BY},
}
RIS
TY - JOUR
TI - RNA viruses can exploit self-cleaving ribozymes for translation initiation
AU - María José López-Galiano
AU - Olga Rueda
AU - Sotaro Chiba
AU - Marco Forgia
AU - Beatriz Navarro
AU - Amelia Cervera
AU - Artem Babaian
AU - Francesco Di Serio
AU - Massimo Turina
AU - Marcos de la Peña
PY - 2026
DA - 2026/10/01
JO - Nucleic Acids Research
DO - 10.1093/nar/gkag1106
UR - https://academic.oup.com/nar/article/doi/10.1093/nar/gkag1106/9006196
AB - Small self-cleaving ribozymes are catalytic RNAs discovered in viroid-like agents, which are replicating circular RNAs (circRNAs) postulated as relics of a prebiotic RNA world. In the last decade, however, small ribozymes have also been detected across the tree of life, from bacterial to human genomes, and more recently, in unusual circRNA viruses. Here we report the conserved occurrence of diverse small ribozymes within the linear genomes of typical single- and double-stranded RNA viruses infecting fungi and plants. We identified type I hammerhead ribozymes in the 5'-UTRs of chrysovirids and fusarivirids, displaying self-cleaving activity in vitro and in vivo. Similar hammerhead, as well as hepatitis delta and twister ribozymes, occur in diverse megabirna-, hypo-, fusagra-, toti-, or tombus-like viruses. The ribozymes appear as isolated motifs within the UTRs or as tandem pairs that encompass small RNA segments (186-399 nt) resembling Zetavirus-like sequences. In vivo characterization of the 5'-UTR from a fungal chrysovirus revealed that its RNA self-cleaving activity is essential for protein translation initiation. Analogous experiments in plants with diverse ribozyme motifs confirmed that self-cleaving activity alone can induce cap-independent translation. We conclude that RNA self-cleaving activity, historically linked to the rolling circle replication of viroid-like circRNAs, appears to be co-opted by some linear RNA viruses for translational roles.
SN - 0305-1048
SN - 1362-4962
ER -