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Gene silencing as an adaptive defence against viruses

Nature volume 411, pages 834–842 (2001)Cite this article

Abstract

Gene silencing was perceived initially as an unpredictable and inconvenient side effect of introducing transgenes into plants. It now seems that it is the consequence of accidentally triggering the plant's adaptive defence mechanism against viruses and transposable elements. This recently discovered mechanism, although mechanistically different, has a number of parallels with the immune system of mammals.

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Figure 1: Potato plants challenged with potato virus Y.
Figure 2: Proposed mechanism, based on RNAi, for dsRNA-directed ssRNA cleavage in PTGS.
Figure 3: Distribution of domains on DCR1-like and AGO1-like proteins.
Figure 4: A model for the initiation and operation of PTGS.
Figure 5: Possible ways in which transposons may generate hpRNA or dsRNA.
Figure 6: Tobacco plants showing potato virus Y (PVY) susceptibility, immunity and resistant/recovery symptoms.
Figure 7: A model for mobile PTGS and methylation signals.

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Acknowledgements

We thank M.-A. Grandbastion, R. Hull and our colleagues at P.I. for being so generous with their time and knowledge. Thanks also to V. Vance for access to her manuscript before publication.

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  1. Tony Lough

    Present address: HortResearch, Tennent Drive, Palmerston North, New Zealand

  2. Tony Lough

    Present address: Genesis Research and Development Corporation, PO Box 50, Auckland, New Zealand

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  1. CSIRO Plant Industry, ACT 2601, Canberra, Australia

    Peter M. Waterhouse, Ming-Bo Wang & Tony Lough

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Waterhouse, P., Wang, MB. & Lough, T. Gene silencing as an adaptive defence against viruses. Nature 411, 834–842 (2001). https://doi.org/10.1038/35081168

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