CRISPR/Cas‐based tools for the targeted control of plant viruses

Abstract

Plant viruses are known to infect most economically important crops and pose a major threat to global food security. Currently, few resistant host phenotypes have been delineated, and while chemicals are used for crop protection against insect pests and bacterial or fungal diseases, these are inefficient against viral diseases. Genetic engineering emerged as a way of modifying the plant genome by introducing functional genes in plants to improve crop productivity under adverse environmental conditions. Recently, new breeding technologies, and in particular the exciting CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR‐associated proteins) technology, was shown to be a powerful alternative to engineer resistance against plant viruses, thus has great potential for reducing crop losses and improving plant productivity to directly contribute to food security. Indeed, it could circumvent the “Genetic modification” issues because it allows for genome editing without the integration of foreign DNA or RNA into the genome of the host plant, and it is simpler and more versatile than other new breeding technologies. In this review, we describe the predominant features of the major CRISPR/Cas systems and outline strategies for the delivery of CRISPR/Cas reagents to plant cells. We also provide an overview of recent advances that have engineered CRISPR/Cas‐based resistance against DNA and RNA viruses in plants through the targeted manipulation of either the viral genome or susceptibility factors of the host plant genome. Finally, we provide insight into the limitations and challenges that CRISPR/Cas technology currently faces and discuss a few alternative applications of the technology in virus research.

Plant translational reprogramming for stress resilience

“…Viruses use various strategies to regulate host translation mechanisms for protein synthesis (Jaafar and Kieft, 2019;Geng et al, 2021). Increasing plant antiviral immunity through manipulation of plant translation factors has been well described in previous reviews (Sanfacon, 2015;Hashimoto et al, 2016;Calil and Fontes, 2017;Zhao et al, 2020;Leonetti et al, 2021;Robertson et al, 2022). Therefore, herein, we focus on recent studies that demonstrate notable translation mechanisms associated with nonviral pathogens.…”

Occurrence, Distribution, and Management of Aphid-Transmitted Viruses in Cucurbits in Spain

“…There are commercially-grown hybrid cultivars of melon with tolerance to aphids, in addition to cultivars carrying the vat gene, which confers resistance to both A. gossypii and the viruses it transmits [ 145 ]. With the means to edit cucurbit genomes directly through the revolutionary CRISPR/Cas9 approach [ 146 ], cucumber lines with mutations that disrupt the eIF4E interaction with viral proteins, which is associated with recessive resistance [ 147 ], have been reported and tested against CVYV, ZYMV, PRSV-W, CMV and CGMMV [ 148 ], and melon lines against MWMV [ 149 ]. This technology is reducing the timeframe needed to obtain cultivars carrying traits of interest and is further underway to incorporate viral disease control into plant crops.…”

Engineering of crop plants to facilitate bottom-up innovation: A possible role for broad host-range nitroplasts and neoplasts

“…A particularly powerful example of gene insertion is the introduction of the gene encoding Cas9 itself (or a different Cas protein), along with sgRNAs directed against various pathogenic viruses. 440 This is the natural use of CRISPR/Cas9, which in bacteria serves as a common defense against infecting phages. 441 In one of many examples, 440 expression in tobacco of Cas13, a variant that recognizes and cuts single-stranded RNA specified by sgRNA, conferred resistance to two serologically distinct natural isolates of Potato Virus Y.…”

“…440 This is the natural use of CRISPR/Cas9, which in bacteria serves as a common defense against infecting phages. 441 In one of many examples, 440 expression in tobacco of Cas13, a variant that recognizes and cuts single-stranded RNA specified by sgRNA, conferred resistance to two serologically distinct natural isolates of Potato Virus Y. 442,443 These viruses are broad-host range, infecting other members of the Solanaceae --tomato, pepper, and tobacco --in addition to potato.…”