Article

Bidirectional cross-kingdom RNAi and fungal uptake of external RNAs confer plant protection

  • Nature Plants 2, Article number: 16151 (2016)
  • doi:10.1038/nplants.2016.151
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Abstract

Aggressive fungal pathogens such as Botrytis and Verticillium spp. cause severe crop losses worldwide. We recently discovered that Botrytis cinerea delivers small RNAs (Bc–sRNAs) into plant cells to silence host immunity genes. Such sRNA effectors are mostly produced by Botrytis cinerea Dicer-like protein 1 (Bc-DCL1) and Bc-DCL2. Here we show that expressing sRNAs that target Bc-DCL1 and Bc-DCL2 in Arabidopsis and tomato silences Bc-DCL genes and attenuates fungal pathogenicity and growth, exemplifying bidirectional cross-kingdom RNAi and sRNA trafficking between plants and fungi. This strategy can be adapted to simultaneously control multiple fungal diseases. We also show that Botrytis can take up external sRNAs and double-stranded RNAs (dsRNAs). Applying sRNAs or dsRNAs that target Botrytis DCL1 and DCL2 genes on the surface of fruits, vegetables and flowers significantly inhibits grey mould disease. Such pathogen gene-targeting RNAs represent a new generation of environmentally friendly fungicides.

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Acknowledgements

We thank H. Vaucheret for the ago1-27 seeds, M. Coffey for the V. dahliae JR2 strain, I. Kaloshian for providing the growth room space for VIGS experiments, and Y. Lii for editing the paper. This work was supported by grants from National Institute of Health (R01 GM093008), National Science Foundation (IOS-1257576, IOS-1557812) and an AES-CE Award (PPA-7517H) awarded to H.J.

Author information

Author notes

    • Arne Weiberg

    Present address: Institute of Genetics, University of Munich, Martinsried, Germany.

Affiliations

  1. Department of Plant Pathology and Microbiology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA

    • Ming Wang
    • , Arne Weiberg
    •  & Hailing Jin
  2. Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsin-Chu 300, Taiwan

    • Feng-Mao Lin
    •  & Hsien-Da Huang
  3. Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands

    • Bart P. H. J. Thomma

Authors

  1. Search for Ming Wang in:

  2. Search for Arne Weiberg in:

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Contributions

H.J. conceived the idea. M.W. and H.J. designed the experiments. M.W. performed most of the experiments and analysed data. A.W. profiled the sRNAs from dcl1 dcl2 and WT strains and analysed the data. F.M.L. and H.D.H. conducted bioinformatics analysis on sRNA libraries. B.T. provided Vd genome sequence for JR2 strain. M.W., A.W. and H.J. wrote the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Hailing Jin.

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    Supplementary Methods, Supplementary Figures 1–9, Supplementary References

Excel files

  1. 1.

    Supplementary Table 1

    The normalized read counts of previously predicted Bc-sRNA effector candidates in B. cinerea WT and dcl1 dcl2 strains

  2. 2.

    Supplementary Table 2

    At-AGO1-associated Vd-sRNA effector candidates and their targets.

  3. 3.

    Supplementary Table 3

    At-AGO2-associated Vd-sRNAs and their targets.

  4. 4.

    Supplementary Table 4

    The list of primers and oligoes used in the manuscript.