Open AccessMimicking natural polymorphism in eIF 4E by CRISPR ‐Cas9 base editing is associated with resistance to potyviruses
Author(s) -
Bastet Anna,
Zafirov Delyan,
Giovinazzo Nathalie,
GuyonDebast Anouchka,
Nogué Fabien,
Robaglia Christophe,
Gallois JeanLuc
Publication year - 2019
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.13096
Subject(s) - biology , genetics , crispr , genome editing , allele , gene , cas9 , point mutation , genetically modified crops , mutant , virology , transgene
Summary In many crop species, natural variation in eIF 4E proteins confers resistance to potyviruses. Gene editing offers new opportunities to transfer genetic resistance to crops that seem to lack natural eIF 4E alleles. However, because eIF 4E are physiologically important proteins, any introduced modification for virus resistance must not bring adverse phenotype effects. In this study, we assessed the role of amino acid substitutions encoded by a Pisum sativum eIF 4E virus‐resistance allele (W69L, T80D S81D, S84A, G114R and N176K) by introducing them independently into the Arabidopsis thaliana eIF 4E1 gene, a susceptibility factor to the Clover yellow vein virus (Cl YVV ). Results show that most mutations were sufficient to prevent Cl YVV accumulation in plants without affecting plant growth. In addition, two of these engineered resistance alleles can be combined with a loss‐of‐function eIF iso4E to expand the resistance spectrum to other potyviruses. Finally, we use CRISPR ‐ nC as9‐cytidine deaminase technology to convert the Arabidopsis eIF 4E1 susceptibility allele into a resistance allele by introducing the N176K mutation with a single‐point mutation through C‐to‐G base editing to generate resistant plants. This study shows how combining knowledge on pathogen susceptibility factors with precise genome‐editing technologies offers a feasible solution for engineering transgene‐free genetic resistance in plants, even across species barriers.