Plant virus-derived small interfering RNAs originate predominantly from highly structured single-stranded viral RNAs

A Molnar, T Csorba, L Lakatos, E Varallyay, C Lacomme, J Burgyan*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

RNA silencing is conserved in a broad range of eukaryotes and includes the phenomena of RNA interference in animals and posttranscriptional gene silencing (PTGS) in plants. In plants, PTGS acts as an antiviral system; a successful virus infection requires suppression or evasion of the induced silencing response. Small interfering RNAs (siRNAs) accumulate in plants infected with positive-strand RNA viruses and provide specificity to this RNA-mediated defense. We present here the results of a survey of virus-specific siRNAs characterized by a sequence analysis of siRNAs from plants infected with Cymbidium ringspot tombusvirus (CymRSV). CymRSV ARNA sequences have a nonrandom distribution along the length of the viral genome, suggesting that there are hot spots for virus-derived siRNA generation. CymRSV siRNAs bound to the CymRSV p19 suppressor protein have the same asymmetry in strand polarity as the sequenced siRNAs and are imperfect double-stranded RNA duplexes. Moreover, an analysis of siRNAs derived from two other nonrelated positive-strand RNA viruses showed that they displayed the same asymmetry as CymRSV siRNAs. Finally, we show that Tobacco mosaic virus (TMV) carrying a short inverted repeat of the phytoene desaturase (PDS) gene triggered more accumulation of PDS siRNAs than the corresponding antisense PDS sequence. Taken together, these results suggest that virus-derived siRNAs originate predominantly by direct DICER cleavage of imperfect duplexes in the most folded regions of the positive strand of the viral RNA.

Original languageEnglish
Pages (from-to)7812-7818
Number of pages7
JournalJournal of Virology
Volume79
Issue number12
DOIs
Publication statusPublished - Jun 2005

Keywords / Materials (for Non-textual outputs)

  • TOBACCO-MOSAIC-VIRUS
  • TRANS-ACTING SIRNAS
  • GENE-EXPRESSION
  • SILENCING SUPPRESSORS
  • IMMUNE-SYSTEM
  • C-ELEGANS
  • MICRORNAS
  • ARABIDOPSIS
  • IDENTIFICATION
  • TOMBUSVIRUSES

Fingerprint

Dive into the research topics of 'Plant virus-derived small interfering RNAs originate predominantly from highly structured single-stranded viral RNAs'. Together they form a unique fingerprint.

Cite this