Molecular bases of viral RNA targeting by viral small interfering RNA-programmed RISC

Vitantonio Pantaleo, G. Szittya, J. Burgyán

Research output: Contribution to journalArticle

110 Citations (Scopus)

Abstract

RNA silencing is conserved in a broad range of eukaryotes and operates in the development and maintenance of genome integrity in many organisms. Plants have adapted this system for antiviral defense, and plant viruses have in turn developed mechanisms to suppress RNA silencing. RNA silencing-related RNA inactivation is likely based on target RNA cleavage or translational arrest. Although it is widely assumed that virus-induced gene silencing (VIGS) promotes the endonucleolytic cleavage of the viral RNA genome, this popular assumption has never been tested experimentally. Here we analyzed the viral RNA targeting by VIGS in tombusvirus-infected plants, and we show evidence that antiviral response of VIGS is based on viral RNA cleavage by RNA-induced silencing effector complex (RISC) programmed by virus-specific small interfering RNAs (siRNAs). In addition, we found that the RISC-mediated cleavages do not occur randomly on the viral genome. Indeed, sequence analysis of cloned cleavage products identified hot spots for target RNA cleavage, and the regions of specific RISC-mediated cleavages are asymmetrically distributed along the positive- and negative-sense viral RNA strands. In addition, we identified viral siRNAs containing high-molecular-mass protein complexes purified from the recovery leaves of the silencing suppressor mutant virus-infected plants. Strikingly, these large nucleoproteins cofractionated with microRNA-containing complexes, suggesting that these nucleoproteins are silencing related effector complexes.

Original languageEnglish
Pages (from-to)3797-3806
Number of pages10
JournalJournal of Virology
Volume81
Issue number8
DOIs
Publication statusPublished - Apr 2007

Fingerprint

RNA-Induced Silencing Complex
Viral RNA
small interfering RNA
Small Interfering RNA
RNA Cleavage
RNA
Gene Silencing
RNA Interference
Plant Viruses
Nucleoproteins
Viral Genome
Viruses
Antiviral Agents
gene silencing
Tombusvirus
RNA interference
viruses
nucleoproteins
RNA Viruses
plant viruses

ASJC Scopus subject areas

  • Immunology

Cite this

Molecular bases of viral RNA targeting by viral small interfering RNA-programmed RISC. / Pantaleo, Vitantonio; Szittya, G.; Burgyán, J.

In: Journal of Virology, Vol. 81, No. 8, 04.2007, p. 3797-3806.

Research output: Contribution to journalArticle

@article{871e0fc284c24eb79e9945bbffe012f8,
title = "Molecular bases of viral RNA targeting by viral small interfering RNA-programmed RISC",
abstract = "RNA silencing is conserved in a broad range of eukaryotes and operates in the development and maintenance of genome integrity in many organisms. Plants have adapted this system for antiviral defense, and plant viruses have in turn developed mechanisms to suppress RNA silencing. RNA silencing-related RNA inactivation is likely based on target RNA cleavage or translational arrest. Although it is widely assumed that virus-induced gene silencing (VIGS) promotes the endonucleolytic cleavage of the viral RNA genome, this popular assumption has never been tested experimentally. Here we analyzed the viral RNA targeting by VIGS in tombusvirus-infected plants, and we show evidence that antiviral response of VIGS is based on viral RNA cleavage by RNA-induced silencing effector complex (RISC) programmed by virus-specific small interfering RNAs (siRNAs). In addition, we found that the RISC-mediated cleavages do not occur randomly on the viral genome. Indeed, sequence analysis of cloned cleavage products identified hot spots for target RNA cleavage, and the regions of specific RISC-mediated cleavages are asymmetrically distributed along the positive- and negative-sense viral RNA strands. In addition, we identified viral siRNAs containing high-molecular-mass protein complexes purified from the recovery leaves of the silencing suppressor mutant virus-infected plants. Strikingly, these large nucleoproteins cofractionated with microRNA-containing complexes, suggesting that these nucleoproteins are silencing related effector complexes.",
author = "Vitantonio Pantaleo and G. Szittya and J. Burgy{\'a}n",
year = "2007",
month = "4",
doi = "10.1128/JVI.02383-06",
language = "English",
volume = "81",
pages = "3797--3806",
journal = "Journal of Virology",
issn = "0022-538X",
publisher = "American Society for Microbiology",
number = "8",

}

TY - JOUR

T1 - Molecular bases of viral RNA targeting by viral small interfering RNA-programmed RISC

AU - Pantaleo, Vitantonio

AU - Szittya, G.

AU - Burgyán, J.

PY - 2007/4

Y1 - 2007/4

N2 - RNA silencing is conserved in a broad range of eukaryotes and operates in the development and maintenance of genome integrity in many organisms. Plants have adapted this system for antiviral defense, and plant viruses have in turn developed mechanisms to suppress RNA silencing. RNA silencing-related RNA inactivation is likely based on target RNA cleavage or translational arrest. Although it is widely assumed that virus-induced gene silencing (VIGS) promotes the endonucleolytic cleavage of the viral RNA genome, this popular assumption has never been tested experimentally. Here we analyzed the viral RNA targeting by VIGS in tombusvirus-infected plants, and we show evidence that antiviral response of VIGS is based on viral RNA cleavage by RNA-induced silencing effector complex (RISC) programmed by virus-specific small interfering RNAs (siRNAs). In addition, we found that the RISC-mediated cleavages do not occur randomly on the viral genome. Indeed, sequence analysis of cloned cleavage products identified hot spots for target RNA cleavage, and the regions of specific RISC-mediated cleavages are asymmetrically distributed along the positive- and negative-sense viral RNA strands. In addition, we identified viral siRNAs containing high-molecular-mass protein complexes purified from the recovery leaves of the silencing suppressor mutant virus-infected plants. Strikingly, these large nucleoproteins cofractionated with microRNA-containing complexes, suggesting that these nucleoproteins are silencing related effector complexes.

AB - RNA silencing is conserved in a broad range of eukaryotes and operates in the development and maintenance of genome integrity in many organisms. Plants have adapted this system for antiviral defense, and plant viruses have in turn developed mechanisms to suppress RNA silencing. RNA silencing-related RNA inactivation is likely based on target RNA cleavage or translational arrest. Although it is widely assumed that virus-induced gene silencing (VIGS) promotes the endonucleolytic cleavage of the viral RNA genome, this popular assumption has never been tested experimentally. Here we analyzed the viral RNA targeting by VIGS in tombusvirus-infected plants, and we show evidence that antiviral response of VIGS is based on viral RNA cleavage by RNA-induced silencing effector complex (RISC) programmed by virus-specific small interfering RNAs (siRNAs). In addition, we found that the RISC-mediated cleavages do not occur randomly on the viral genome. Indeed, sequence analysis of cloned cleavage products identified hot spots for target RNA cleavage, and the regions of specific RISC-mediated cleavages are asymmetrically distributed along the positive- and negative-sense viral RNA strands. In addition, we identified viral siRNAs containing high-molecular-mass protein complexes purified from the recovery leaves of the silencing suppressor mutant virus-infected plants. Strikingly, these large nucleoproteins cofractionated with microRNA-containing complexes, suggesting that these nucleoproteins are silencing related effector complexes.

UR - http://www.scopus.com/inward/record.url?scp=34247168131&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34247168131&partnerID=8YFLogxK

U2 - 10.1128/JVI.02383-06

DO - 10.1128/JVI.02383-06

M3 - Article

C2 - 17267504

AN - SCOPUS:34247168131

VL - 81

SP - 3797

EP - 3806

JO - Journal of Virology

JF - Journal of Virology

SN - 0022-538X

IS - 8

ER -