Plant Cell BIOBASE Corporation
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Cell Advance Online Publication
Published on June 22, 2007; 10.1105/tpc.106.047449

OPEN ACCESS ARTICLE
This Article
Free via Open Access: OA
Right arrow Full Text - TPC Advance Online Pub. (PDF)
Right arrow Supplemental Data
Right arrowOA All Versions of this Article:
19/6/2053    most recent
tpc.106.047449v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Diaz-Pendon, J. A.
Right arrow Articles by Ding, S.-W.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Diaz-Pendon, J. A.
Right arrow Articles by Ding, S.-W.
Agricola
Right arrow Articles by Diaz-Pendon, J. A.
Right arrow Articles by Ding, S.-W.

Received September 26, 2006
Returned for revision May 24, 2007
Accepted June 4, 2007

Suppression of Antiviral Silencing by Cucumber Mosaic Virus 2b Protein in Arabidopsis Is Associated with Drastically Reduced Accumulation of Three Classes of Viral Small Interfering RNAs

Juan A. Diaz-Pendon 1, Feng Li 1, Wan-Xiang Li 1, and Shou-Wei Ding 1*

1 Center for Plant Cell Biology, Department of Plant Pathology and Microbiology, University of California, Riverside, California 92521

* To whom correspondence should be addressed. E-mail: dingsw{at}ucr.edu.

We investigated the genetic pathway in Arabidopsis thaliana targeted during infection by cucumber mosaic virus (CMV) 2b protein, known to suppress non-cell-autonomous transgene silencing and salicylic acid (SA)-mediated virus resistance. We show that 2b expressed from the CMV genome drastically reduced the accumulation of 21-, 22-, and 24-nucleotide classes of viral small interfering RNAs (siRNAs) produced by Dicer-like4 (DCL4), DCL2, and DCL3, respectively. The defect of a CMV 2b-deletion mutant (CMV-{Delta}2b) in plant infection was efficiently rescued in Arabidopsis mutants producing neither 21- nor 22-nucleotide viral siRNAs. Since genetic analysis further identifies a unique antiviral role for DCL3 upstream of DCL4, our data indicate that inhibition of the accumulation of distinct viral siRNAs plays a key role in 2b suppression of antiviral silencing. Strikingly, disease symptoms caused by CMV-{Delta}2b in Arabidopsis mutants defective in antiviral silencing were as severe as those caused by CMV, demonstrating an indirect role for the silencing suppressor activity in virus virulence. We found that production of CMV siRNAs without 2b interference depended largely on RNA-dependent RNA polymerase 1 (RDR1) inducible by SA. Given the known role of RDR6-dependent transgene siRNAs in non-cell-autonomous silencing, our results suggest a model in which 2b inhibits the production of RDR1-dependent viral siRNAs that confer SA-dependent virus resistance by directing non-cell-autonomous antiviral silencing.




This article has been cited by other articles:


Home page
 J. Virol.Home page
L. Donaire, D. Barajas, B. Martinez-Garcia, L. Martinez-Priego, I. Pagan, and C. Llave
Structural and Genetic Requirements for the Biogenesis of Tobacco Rattle Virus-Derived Small Interfering RNAs
J. Virol., June 1, 2008; 82(11): 5167 - 5177.
[Abstract] [Full Text] [PDF]

Home page
 J. Virol.Home page
K. Hirai, K. Kubota, T. Mochizuki, S. Tsuda, and T. Meshi
Antiviral RNA Silencing Is Restricted to the Marginal Region of the Dark Green Tissue in the Mosaic Leaves of Tomato Mosaic Virus-Infected Tobacco Plants
J. Virol., April 1, 2008; 82(7): 3250 - 3260.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
H. B. Scholthof
Heterologous Expression of Viral RNA Interference Suppressors: RISC Management
Plant Physiology, December 1, 2007; 145(4): 1110 - 1117.
[Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications THE PLANT CELL PLANT PHYSIOLOGY
Copyright © 2007 by the American Society of Plant Biologists