Viroids: the minimal non-coding RNAs with autonomous replication.

Ricardo Flores; Sonia Delgado; María-Eugenia Gas; Alberto Carbonell; Diego Molina; Selma Gago; Marcos De la Peña

doi:10.1016/j.febslet.2004.03.118

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Viroids: the minimal non-coding RNAs with autonomous replication.

Ricardo Flores·Sonia Delgado·María-Eugenia Gas·Alberto Carbonell·Diego Molina·Selma Gago·Marcos De la Peña

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Abstract

Viroids are small (246-401 nucleotides), non-coding, circular RNAs able to replicate autonomously in certain plants. Viroids are classified into the families Pospiviroidae and Avsunviroidae, whose members replicate in the nucleus and chloroplast, respectively. Replication occurs by an RNA-based rolling-circle mechanism in three steps: (1). synthesis of longer-than-unit strands catalyzed by host DNA-dependent RNA polymerases forced to transcribe RNA templates, (2). processing to unit-length, which in family Avsunviroidae is mediated by hammerhead ribozymes, and (3). circularization either through an RNA ligase or autocatalytically. Disease induction might result from the accumulation of viroid-specific small interfering RNAs that, via RNA silencing, could interfere with normal developmental pathways.

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Base Sequence DNA Gene Silencing Models, Biological Models, Genetic Molecular Sequence Data Nucleic Acid Conformation Plant Viruses RNA RNA Interference RNA Processing, Post-Transcriptional RNA, Catalytic Viroids Virus Replication Journal Article Research Support, Non-U.S. Gov't Review

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Ricardo Flores, Sonia Delgado, María-Eugenia Gas, Alberto Carbonell, Diego Molina, Selma Gago, Marcos De la Peña. 2004-06-01. Viroids: the minimal non-coding RNAs with autonomous replication.. https://doi.org/10.1016/j.febslet.2004.03.118

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