Viroids, and the Legacy of Ricardo Flores (1947–2020)
Funding
Conflicts of Interest
References
- Hadidi, A.; Flores, R.; Randles, J.W.; Semancik, J.S. (Eds.) Viroids; CSIRO Publishing: Collingwood, Australia, 2003; p. 370. [Google Scholar]
- Hadidi, A.; Flores, R.; Randles, J.W.; Palukaitis, P. (Eds.) Viroids and Satellites; Academic Press/Elsevier: Oxford, UK; Cambridge, MA, USA, 2017; p. 716. [Google Scholar]
- Daros, J.A.; Marcos, J.F.; Hernandez, C.; Flores, R. Replication of avocado sunblotch viroid: Evidence for a symmetric pathway with two rolling circles and hammerhead ribozyme processing. Proc. Natl. Acad. Sci. USA 1994, 91, 12813–12817. [Google Scholar] [CrossRef] [Green Version]
- Flores, R.; Daros, J.A.; Hernandez, C. The Avsunviroidae family: Viroids with hammerhead ribozymes. Adv. Virus Res. 2000, 55, 271–323. [Google Scholar]
- Flores, R.; Grubb, D.; Elleuch, A.; Nohales, M.A.; Delgado, S.; Gago, S. Rolling-circle replication of viroids, viroid-like satellite RNAs and hepatitis delta virus: Variations on a theme. RNA Biol. 2011, 8, 200–206. [Google Scholar] [CrossRef] [Green Version]
- Navarro, J.A.; Daros, J.A.; Flores, R. Complexes containing both polarity strands of avocado sunblotch viroid: Identification in chloroplasts and characterization. Virology 1999, 253, 77–85. [Google Scholar] [CrossRef]
- Flores, R.; Semancik, J.S. Properties of a cell-free system for synthesis of citrus exocortis viroid. Proc. Natl. Acad. Sci. USA 1982, 79, 6285–6288. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Navarro, J.A.; Vera, A.; Flores, R. A chloroplastic RNA polymerase resistant to tagetitoxin is involved in replication of avocado sunblotch viroid. Virology 2000, 268, 218–225. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Rodio, M.E.; Delgado, S.; De Stradis, A.E.; Gomez, M.D.; Flores, R.; Di Serio, F. A viroid RNA with a specific structural motif inhibits chloroplast development. Plant Cell 2007, 19, 3610–3626. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Delgado, S.; Martınez de Alba, E.; Hernandez, C.; Flores, R. A short double-stranded RNA motif of peach latent mosaic viroid contains the initiation and the self-cleavage sites of both polarity strands. J. Virol. 2005, 79, 12934–12943. [Google Scholar] [CrossRef] [Green Version]
- Navarro, J.A.; Flores, R. Characterization of the initiation sites of both polarity strands of a viroid RNA reveals a motif conserved in sequence and structure. EMBO J. 2000, 19, 2662–2670. [Google Scholar] [CrossRef] [Green Version]
- Hutchins, C.; Rathjen, P.D.; Forster, A.C.; Symons, R.H. Self-cleavage of plus and minus RNA transcripts of avocado sunblotch viroid. Nucleic Acids Res. 1986, 14, 3627–3640. [Google Scholar] [CrossRef]
- De la Pena, M.; Gago, S.; Flores, R. Peripheral regions of natural hammerhead ribozymes greatly increase their self-cleavage activity. EMBO J. 2003, 22, 5561–5570. [Google Scholar] [CrossRef] [Green Version]
- Khvorova, A.; Lescoute, A.; Westhof, E.; Jayasena, S.D. Sequence elements outside the hammerhead ribozyme catalytic core enable intracellular activity. Nat. Struct. Biol. 2003, 10, 708–712. [Google Scholar] [CrossRef]
- Daros, J.A.; Flores, R. A chloroplast protein binds a viroid RNA in vivo and facilitates its hammerhead-mediated self-cleavage. EMBO J. 2002, 21, 749–759. [Google Scholar] [CrossRef] [Green Version]
- Gas, M.E.; Hernandez, C.; Flores, R.; Daros, J.A. Processing of nuclear viroids in vivo: An interplay between RNA conformations. PLoS Pathog. 2007, 3, 1813–1826. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Diener, T.O. Viroid processing: A model involving the central conserved region and hairpin I. Proc. Natl. Acad. Sci. USA 1986, 83, 58–62. [Google Scholar] [CrossRef] [Green Version]
- Visvader, J.E.; Forster, A.C.; Symons, R.H. Infectivity and in vitro mutagenesis of monomeric cDNA clones of citrus exocortis viroid indicates the site of processing of viroid precursors. Nucleic Acids Res. 1985, 13, 5843–5856. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Gas, M.E.; Molina-Serrano, D.; Hernandez, C.; Flores, R.; Daros, J.A. Monomeric linear RNA of citrus exocortis viroid resulting from processing in vivo has 5’-phosphomonoester and 3’-hydroxyl termini: Implications for the ribonuclease and RNA ligase involved in replication. J. Virol. 2008, 82, 10321–10325. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Nohales, M.A.; Flores, R.; Daros, J.A. A viroid RNA redirects host DNA ligase 1 to act as an RNA ligase. Proc. Natl. Acad. Sci. USA 2012, 109, 13805–13810. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Nohales, M.A.; Molina-Serrano, D.; Flores, R.; Daros, J.A. Involvement of the chloroplastic isoform of tRNA ligase in the replication of the viroids belonging to the family Avsunviroidae. J. Virol. 2012, 86, 8269–8276. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Ambros, S.; Hernandez, C.; Desvignes, J.C.; Flores, R. Genome structure of three phenotypically different isolates of peach latent mosaic viroid: Implications of the existence of constraints limiting the heterogeneity of viroid quasi-species. J. Virol. 1998, 72, 7397–7406. [Google Scholar] [CrossRef] [Green Version]
- Hernandez, C.; Flores, R. Plus and minus RNAs of peach latent mosaic viroid self-cleave in vitro via hammerhead structures. Proc. Natl. Acad. Sci. USA 1992, 89, 3711–3715. [Google Scholar] [CrossRef] [Green Version]
- Gago, S.; Elena, S.F.; Flores, R.; Sanjuan, R. Extremely high variability of a hammerhead viroid. Science 2009, 323, 1308. [Google Scholar] [CrossRef] [Green Version]
- Shamloul, A.M.; Minafra, A.; Hadidi, A.; Giunchedi, L.; Waterworth, H.E.; Allam, E.K. Peach latent mosaic viroid nucleotide sequence of an Italian isolate, sensitive detection using RT-PCR and geographic distribution. Acta Hortic. 1995, 386, 522–530. [Google Scholar] [CrossRef]
- Hernandez, C.; Di Serio, F.; Daros, J.A.; Flores, R. An element of tertiary structure of peach latent mosaic viroid RNA revealed by UV irradiation. J. Virol. 2006, 80, 9336–9340. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Fadda, Z.; Daros, J.; Fagoaga, C.; Flores, R.; Duran-Villa, N. Eggplant latent viroid, the candidate type species for a new genus within the family Avsunviroidae (hammer-head viroids). J. Virol. 2003, 77, 6528–6532. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Steger, G.; Riesner, D.; Maurel, M.-C.; Perreault, J.-P. Viroid Structure. In Viroids and Satellites; Hadidi, A., Flores, R., Randles, J.W., Palukaitis, P., Eds.; Academic Press/Elsevier: Oxford, UK; Cambridge, MA, USA, 2017; pp. 63–70. [Google Scholar]
- Eiras, M.; Nohales, M.A.; Kitajima, E.W.; Flores, R.; Daros, J.A. Ribosomal protein L5 and transcription factor IIIA from Arabidopsis thaliana bind in vitro specifically potato spindle tuber viroid RNA. Arch. Virol. 2011, 156, 529–533. [Google Scholar] [CrossRef] [PubMed]
- Flores, R.; Di Serio, F.; Navarro, B.; Owens, R.A. Viroid pathogenesis. In Viroids and Satellites; Hadidi, A., Flores, R., Randles, J.W., Palukaitis, P., Eds.; Academic Press/Elsevier: Oxford, UK; Cambridge, MA, USA, 2017; pp. 93–103. [Google Scholar]
- Flores, R.; Navarro, B.; Delgado, S.; Serra, P.; Di Serio, F. Viroid pathogenesis: A critical appraisal of the role of RNA silencing in triggering the initial molecular lesion. FEMS Microbiol. Rev. 2020, 44, 386–398. [Google Scholar] [CrossRef]
- Diener, T.O. Circular RNAs: Relics of precellular evolution? Proc. Natl. Acad. Sci. USA 1989, 86, 9370–9374. [Google Scholar] [CrossRef] [Green Version]
- Flores, R.; Gago-Zachert, S.; Serra, P.; Sanjuan, R.; Elena, S.F. Viroids, survivors from the RNA world? Annu. Rev. Microbiol. 2014, 68, 395–414. [Google Scholar] [CrossRef] [Green Version]
- Elena, S.F.; Dopazo, J.; de la Pena, M.; Flores, R.; Diener, T.O.; Moya, A. Phylogenetic analysis of viroid and viroid-like satellite RNAs from plants: A reassessment. J. Mol. Evol. 2001, 53, 155–159. [Google Scholar] [CrossRef]
- Elena, S.F.; Dopazo, J.; Flores, R.; Diener, T.O.; Moya, A. Phylogeny of viroids, viroid-like satellite RNAs and the viroid-like domain of hepatitis delta virus RNA. Proc. Natl. Acad. Sci. USA 1991, 88, 5531–5634. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Hadidi, A.; Barba, M.; Candresse, T.; Jelkmann, W. (Eds.) Virus and Virus-Like Diseases of Pome and Stone Fruits; The American Phytopathological Society (APS) Press: St. Paul, MN, USA, 2011; p. 429. [Google Scholar]
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Hadidi, A.; Randles, J.W. Viroids, and the Legacy of Ricardo Flores (1947–2020). Cells 2021, 10, 2570. https://doi.org/10.3390/cells10102570
Hadidi A, Randles JW. Viroids, and the Legacy of Ricardo Flores (1947–2020). Cells. 2021; 10(10):2570. https://doi.org/10.3390/cells10102570
Chicago/Turabian StyleHadidi, Ahmed, and John W. Randles. 2021. "Viroids, and the Legacy of Ricardo Flores (1947–2020)" Cells 10, no. 10: 2570. https://doi.org/10.3390/cells10102570