Viral-inducible Argonaute18 confers broad-spectrum virus resistance in rice by sequestering a host microRNA
- Peking University, China
- Tsinghua University, China
- Jiangsu Academy of Agricultural Sciences, China
- Chinese Academy of Agricultural Sciences, China
- Institute of Genetics and Developmental Biology, China
- Fujian Agriculture and Forestry University, China
Abstract
Viral pathogens are a major threat to rice production worldwide. Although RNA interference (RNAi) is known to mediate antiviral immunity in plant and animal models, the mechanism of antiviral RNAi in rice and other economically important crops is poorly understood. Here, we report that rice resistance to evolutionarily diverse viruses requires Argonaute18 (AGO18). Genetic studies reveal that the antiviral function of AGO18 depends on its activity to sequester microRNA168 (miR168) to alleviate repression of rice AGO1 essential for antiviral RNAi. Expression of miR168-resistant AGO1a in ago18 background rescues or increases rice antiviral activity. Notably, stable transgenic expression of AGO18 confers broad-spectrum virus resistance in rice. Our findings uncover a novel cooperative antiviral activity of two distinct AGO proteins and suggest a new strategy for the control of viral diseases in rice.
Article and author information
Author details
Reviewing Editor
- David Baulcombe, University of Cambridge, United Kingdom
Version history
- Received: November 22, 2014
- Accepted: February 13, 2015
- Accepted Manuscript published: February 17, 2015 (version 1)
- Version of Record published: March 13, 2015 (version 2)
Copyright
© 2015, Wu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Viral-inducible Argonaute18 confers broad-spectrum virus resistance in rice by sequestering a host microRNA
eLife 4:e05733.
https://doi.org/10.7554/eLife.05733
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