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


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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Available from: Margit Laimer, Oct 03, 2015
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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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    ABSTRACT: The potyvirus-induced passion fruit woodiness disease (PWD) is considered the most important limiting factor for passion fruit production in several countries. In Brazil, PWD is caused by the Cowpea aphid-borne mosaic virus (CABMV), and to date there are no reports on the existence of P. edulis genotypes resistant to this virus. Thus, resistance gene introgression from wild Passiflora species for a commercial species, via interspecific hybridization, is one of the strategies adopted in order to control the disease. The current study’s goals were to: confirm CABMV occurrence under field conditions; assess the resistance to CABMV in 178 Passiflora genotypes constituted by interspecific hybrids and their parents (P. edulis and P. setacea), as well as to estimate genetic parameters for the area under the disease progress curve (AUDPC), in order to obtain cultivars of sour passion fruit resistant to CABMV in future. The experimental design was set according to unbalanced randomized blocks with two repetitions. Data referring to the AUDPC were analyzed by means of the mixed models methodology (REMI/BLUP). CABMV infections were confirmed in sour passion fruit plants and in interspecific hybrids by observing foliar mosaic symptoms and by PTA-ELISA with specific antiserum against CABMV. There was a difference on the intensity of symptoms induced by CABMV for the 178 Passiflora genotypes assessed under natural occurrence conditions. The higher AUDPC values were obtained for 41 hybrids and for all P. edulis genotypes. In turn, lower values were estimated for 115 hybrid genotypes and for all P. setacea individuals. Of the 31 genotypes assessed by PTA-ELISA, 28 were considered resistant, out of those three P. setacea genotypes and 25 hybrids. Estimated AUDPC heritability values (0.99) and accuracy (0.99) enable inferring that resistance to CABMV within the assessed population was highly inheritable, allowing high selective efficiency. Resistant hybrid plants will be able to be selected and recombined with P. edulis genotypes and, again, assessed in order to corroborate the resistance to the virus, providing means of following up with the breeding genetic program on CABMV resistance.
    European Journal of Plant Pathology 05/2015; DOI:10.1007/s10658-015-0667-y · 1.49 Impact Factor
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    • "Plant viruses cause devastating losses in agriculture, particularly , in economic crops traded across the world. This trading in turn, participates in spreading the viruses and expands the problems with plant infection (Prins et al. 2008). The worldwide virus propagation boosts the demand to develop new strategies to control viral diseases (Boonrod et al. 2004). "
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    ABSTRACT: Worldwide, plant viral infections decrease seriously the crop production yield, boosting the demand to develop new strategies to control viral diseases. One of these strategies to prevent viral infections, based on the immunomodulation faces many problems related to the ectopic expression of specific antibodies in planta. Camelid nanobodies, expressed in plants, may offer a solution as they are an attractive tool to bind efficiently to viral epitopes, cryptic or not accessible to conventional antibodies. Here, we report a novel, generic approach that might lead to virus resistance based on the expression of camelid specific nanobodies against Broad bean mottle virus (BBMV). Eight nanobodies, recognizing BBMV with high specificity and affinity, were retrieved after phage display from a large 'immune' library constructed from an immunized Arabic camel. By an in vitro assay we demonstrate how three nanobodies attenuate the BBMV spreading in inoculated Vicia faba plants. Furthermore, the in planta transient expression of these three selected nanobodies confirms their virus neutralizing capacity. In conclusion, this report supports that plant resistance against viral infections can be achieved by the in vivo expression of camelid nanobodies.
    Plant Molecular Biology 02/2015; 87(4-5). DOI:10.1007/s11103-015-0282-5 · 4.26 Impact Factor
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    • "The CP mediated resistance has been successfully applied to numerous crop species (Prins, 2003; Pang et al., 2000). Currently, various new technologies are being used like antisense RNA, RNAi, siRNA, miRNA to develop transgenic plants for virus resistance (Agrawal et al., 2003; Shelly et al., 2005; Brodersen et al., 2008; Prins et al., 2008; Ai et al., 2011; Vu et al., 2012; Ali et al., 2013). A number of CLCuV genome and b DNA fragments can be exploited to repress the expression of viral genes. "
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    ABSTRACT: Cotton leaf curl virus (CLCuV) is a serious pathogen causing leaf curl disease and affecting the cotton production in major growing areas. The transgenic cotton (Gossypium hirsutum cv. Coker 310) plants were developed by using βC1 gene in antisense orientation gene driven by Cauliflower mosaic virus-35S promoter and nos (nopaline synthase) terminator and mediated by Agrobacterium tumefaciens transformation and somatic embryogenesis system.Molecular confirmation of the transformants was carried by polymerase chain reaction (PCR) and Southern blot hybridization. The developed transgenic and inoculated plants remained symptomless till their growth period. In conclusion, the plants were observed as resistant ot CLCuV.
    Saudi Journal of Biological Sciences 11/2014; 67. DOI:10.1016/j.sjbs.2014.11.013 · 1.26 Impact Factor
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