Biology subjects

Gallois, J.-L.

Publications and source records attributed to Gallois, J.-L..

4 recordsLinked to original sources

bioRxiv2025

Restricted edition of ALS is required during co-edition in order to maintain normal tomato development

Co-editing strategies have emerged as an approach to facilitate the selection of CRISPR/Cas-mediated mutants in a transgene-free manner: the gene of interest is edited together with a reporter gene, whose mutation can be selected visually or pharmacologically. In this work, we asses the impact of editing the well-used reporter Acetolactate synthase (ALS) on plant development and metabolome. We show that the desired mutation in ALS1 (P186S) conferring selectable herbicide resistance trait does not show significant impact on the plant morphology and physiology but that the additional mutations resulting from the same sgRNA can result in reduced vegetative vigor and altered metabolomic profiles in tomato.

plant biology↗

bioRxiv2023

Interdependence of a kinase and its cognate substrate plasma membrane nanoscale dynamics underlies Arabidopsis response to viral infection

Plant viruses represent a risk to agricultural production and as only a few treatments exist, it is urgent to identify resistance mechanisms and factors. In plant immunity, plasma membrane (PM)-localized proteins play an essential role in sensing the extracellular threat presented by bacteria, fungi or herbivores. Viruses are intracellular pathogens and as such the role of the plant PM in detection and resistance against viruses is often overlooked. We investigated the role of the partially PM-bound Calcium-dependent protein kinase 3 (CPK3) in viral infection and we discovered that it displayed a specific ability to hamper viral propagation over CPK isoforms that are involved in immune response to extracellular pathogens. More and more evidence support that the lateral organization of PM proteins and lipids underlies signal transduction in plants. We showed here that CPK3 diffusion in the PM is reduced upon activation as well as upon viral infection and that such immobilization depended on its substrate, Remorin (REM1.2), a scaffold protein. Furthermore, we discovered that the viral infection induced a CPK3-dependent increase of REM1.2 PM diffusion. Such interdependence was also observable regarding viral propagation. This study unveils a complex relationship between a kinase and its substrate that contrasts with the commonly described co-stabilisation upon activation while it proposes a PM-based mechanism involved in decreased sensitivity to viral infection in plants.

plant biology↗

bioRxiv2023

Molecular crosstalk between plant translation initiation complexes influences the outcome of virus infection

Successful subversion of translation initiation factors 4E and 4G determines the infection success of potyviruses, the largest group of viruses affecting plants. In the natural variability of many plant species, resistance to potyvirus infection is provided by polymorphisms at 4E and 4G that renders them inadequate for virus hijacking but still functional in translation initiation. In crops where such natural resistance alleles are limited, the genetic inactivation of 4E has been proposed for the engineering of potyvirus resistance. However, recent findings indicate that knockout 4E and 4G alleles may be deleterious for plant health and could jeopardize resistance efficiency in comparison to functional resistance proteins. Here, we explored the cause of these adverse effects by studying the role of the Arabidopsis eIF4E1, whose inactivation was previously reported as conferring resistance to the potyvirus clover yellow vein virus (ClYVV) while also promoting susceptibility to another potyvirus called turnip mosaic virus (TuMV). We report that eIF4E1 is required to maintain global plant translation and to restrict TuMV accumulation during infection, and its absence is associated with a favoured virus multiplication over host translation. Furthermore, our findings demonstrate that eIF4E1 plays a crucial role in inhibiting the TuMV-induced degradation of the translation initiation factor eIFiso4G1, thereby preventing the generation of a truncated protein. Finally, we demonstrate a role for eIFiso4G1 in TuMV accumulation and in supporting plant fitness during infection. These findings suggest that eIF4E1 counteracts the hijacking of the plant translational apparatus during TuMV infection and underscore the importance of preserving the functionality of translation initiation factors 4E and 4G when implementing potyvirus resistance strategies. Author summaryPlants are constantly under threat from viruses that can damage crops and reduce yield. Among these viruses, potyviruses are a major concern, and a small group of genes known as eIF4E are key factors in making a plant susceptible to them. To combat these viruses, it is possible to either use naturally-selected variants of eIF4E that provide resistance, or to disable the gene altogether. However, new research has shown that inactivating eIF4E genes may have unintended consequences for the plants development while compromise resistance to other potyviruses. To investigate this further, we focus in this work on the role of the Arabidopsis eIF4E1 whose inactivation confers resistance to one potyvirus, clover yellow vein virus (ClYVV). We looked why this same mutation at eIF4E1 makes the plants more susceptible to another potyvirus, turnip mosaic virus (TuMV). Our study reveals that eIF4E1 acts in safeguarding the plant translational machinery during TuMV infection. By preventing the degradation of the translation initiation protein eIFiso4G1, eIF4E1 enables the plant to maintain its normal translation activity and ultimately prevents the accumulation of virus proteins. Our findings provide valuable insights into how potyviruses hijack the plants translation process, and emphasizes the need of preserving the functionality of translation initiation factors when developing potyvirus resistances.

plant biology↗

bioRxiv2020

Prime editing is achievable in the tetraploid potato, but needs improvement

Since its discovery and first applications for genome editing in plants, the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technology has revolutionized plant research and precision crop breeding. Although the classical CRISPR-Cas9 system is highly useful for the introduction of targeted small mutations for knock-out applications, this system is mostly inefficient for the introduction of precise and predictable nucleotide substitutions. Recently, the prime editing (PE) technology has been developed in human cells, allowing the introduction of all kinds of mutations, including the simultaneous generation of nucleotide transitions and transversions. Therefore, this system holds great promises for the production of gain-of-function mutants and for the improvement of precision breeding in crops. In this study, we report on the successful use of prime editing in the tetraploid and highly heterozygous potato (Solanum tuberosum) with the introduction of simultaneous nucleotide transitions and transversions in the StALS1 gene.

plant biology↗