Article

Strategies for antiviral resistance in transgenic plants. Mol Plant Pathol 9:73-83

Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD, Wageningen, The Netherlands.
Molecular Plant Pathology (Impact Factor: 4.72). 02/2008; 9(1):73-83. DOI: 10.1111/j.1364-3703.2007.00447.x
Source: PubMed

ABSTRACT

Genetic engineering offers a means of incorporating new virus resistance traits into existing desirable plant cultivars. The initial attempts to create transgenes conferring virus resistance were based on the pathogen-derived resistance concept. The expression of the viral coat protein gene in transgenic plants was shown to induce protective effects similar to classical cross protection, and was therefore distinguished as 'coat-protein-mediated' protection. Since then, a large variety of viral sequences encoding structural and non-structural proteins were shown to confer resistance. Subsequently, non-coding viral RNA was shown to be a potential trigger for virus resistance in transgenic plants, which led to the discovery of a novel innate resistance in plants, RNA silencing. Apart from the majority of pathogen-derived resistance strategies, alternative strategies involving virus-specific antibodies have been successfully applied. In a separate section, efforts to combat viroids in transgenic plants are highlighted. In a final summarizing section, the potential risks involved in the introduction of transgenic crops and the specifics of the approaches used will be discussed.

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    • "In the past few decades, many transgenic plants have been developed with resistance against bacteria, viruses, and viroids (Fitchen and Beachy 1993;Ishida et al. 2002;Prins et al. 2008). Specifically, transgenic plants expressing recombinant dsRNA-specific RNases display a broad spectrum resistance to a variety of plant RNA viruses and viroids (Fitchen and Beachy 1993;Prins et al. 2008;Sano et al. 1997). Some companies have developed transgenic plants tolerant to herbicide and harmful insect (Prado et al. 2014). "
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    • "The age of the plants is also an important variable related to the disease, since some genotypes present different responses (susceptibility or resistance) when they are inoculated in seedling stages or when they are adult plants (Leão et al. 2006; Pinto et al. 2008). Fig. 6 Ratings of the severity of symptoms incited by CABMV in three UENFH-9 progeny genotypes based on scores weekly recorded between August and December 2012 Eur J Plant Pathol The posttranscriptional gene silencing (PTGS) mechanism or RNA silencing is another factor that may explain the disease symptom regression on hybrid genotypes over time (Prins et al. 2008). The observation that plants which have recovered from a first viral infection become resistant to reinfection with the same virus due to silencing activation and conservation, led to the hypothesis that RNA silencing would be an adaptive defense response to the virus (Al-Kaff et al. 1998). "
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