Biology subjects

Roby, D.

Publications and source records attributed to Roby, D..

4 recordsLinked to original sources

bioRxiv2025

An Arabidopsis receptor-like kinase mediates competitive plant-plant interactions

While competition among plant species is recognized as a major factor affecting crop yield and plant community dynamics, the genetic and molecular mechanisms underlying natural variation of such biotic interactions remain poorly characterized. Here, we report the cloning of a Quantitative Trait Locus previously detected in a Genome-Wide Association Study investigating the competitive response of Arabidopsis thaliana to the presence of the annual bluegrass weed species Poa annua. Using mutant and complementation strategies, we identified ESCAPE 1 (ESC1) as the gene responsible for the natural variation of an escape strategy of A. thaliana in response to the presence of P. annua. ESC1 encodes a proline-rich, extensin-like receptor kinase, also known as PERK13. An RNA-seq experiment revealed that PERK13 functions through different pathways in leaves and roots involving genes associated with responses to biotic and abiotic stresses. Using these RNA-seq together with yeast two-hybrid (Y2H) data, protein-protein interaction network reconstruction revealed two distinct decentralized protein networks in leaves and roots. These findings support the notion of an active response mechanism involved in neighbor detection. The functional validation of ESC1 underlying natural variation in response to competition opens new avenues for a better understanding of the molecular dialogue involved in plant-plant interactions. HighlightIn this study, we identify a receptor-like kinase enabling Arabidopsis thaliana to detect neighboring species through the activation of specific genetic pathways.

plant biology↗

bioRxiv2024

The Arabidopsis leucine rich repeat receptor-like kinase MIK2 interacts with RKS1 and participates to the control of quantitative disease resistance to the bacterial pathogen Xanthomonas campestris

Molecular mechanisms underlying qualitative resistance have been intensively studied. In contrast, although quantitative disease resistance (QDR) is a common, durable and broad-spectrum form of immune responses in plants, only a few related functional analyses have been reported. In this context, the atypical kinase RKS1 is a major actor of QDR to the bacterial pathogen Xanthomonas campestris (Xcc) and is positioned in a robust protein-protein decentralized network. Among the putative interactors of RKS1 found by yeast two hybrid screening, we identified the receptor like kinase MDIS1-Interacting Receptor-like Kinase 2 (MIK2). Here, by multiple and complementary strategies including protein-protein interaction tests, mutant analysis and network reconstruction, we report that MIK2 is a component of RKS1 mediated QDR to Xcc. First, by co-localization experiment, co-immunoprecipitation (Co-IP) and Bimolecular Fluorescence Complementation (BiFC), we validated the physical interaction between RKS1 and MIK2 in the plasma membrane. Using mik2 mutants, we then showed that MIK2 is required for QDR at the same level as RKS1. Interestingly, a catalytic mutant of MIK2 was able to interact with RKS1 but unable to fully complement the mik2-1 mutant in response to Xcc. Finally, we investigated a potential role of the MIK2-RKS1 complex as a scaffolding component for coordination of perception events, by constructing a RKS1-MIK2 centered protein-protein network. Eight mutants corresponding to seven RLKs of this network showed a strong and significant alteration in QDR to Xcc. Our findings provide new insights into the molecular mechanisms underlying perception events involved in QDR to Xcc.

plant biology↗

bioRxiv2019

The genomic architecture of competitive response of Arabidopsis thaliana is highly flexible between monospecific and plurispecific neighborhoods.

Although plants simultaneously interact with multiple neighboring species throughout their life cycle, there is still very limited information about the genetics of the competitive response in the context of plurispecific interactions. Using a local mapping population of Arabidopsis thaliana, we set up a Genome Wide Association study to estimate the extent of genetic variation of the competitive response in presence of 12 plant species assemblages, and to compare the genetic architecture of the competitive response between monospecific and plurispecific neighborhoods. Based on four phenotypic traits, we detected strong crossing reaction norms not only among the three monospecific neighborhoods, but also among the different plant assemblages. Accordingly, the genetic architecture of the competitive response was highly dependent on the identity and the relative abundance of the neighboring species. In addition, enriched biological processes underlying the competitive response largely differ between monospecific and plurispecific neighborhoods. In particular, receptor-like kinases and transporters were significantly enriched in plurispecific neighborhoods. Our results suggest that plants can integrate and respond to different species assemblages depending on the identity and number of each neighboring species, through a large range of genes associated mainly with perception and signaling processes leading to developmental and stress responses.

genetics↗

bioRxiv2018

In situ relationships between microbiota and potential pathobiota in Arabidopsis thaliana

A current challenge in microbial pathogenesis is to identify biological control agents that may prevent and/or limit host invasion by microbial pathogens. In natura, hosts are often infected by multiple pathogens. However, most of the current studies have been performed under laboratory controlled conditions and by taking into account the interaction between a single commensal species and a single pathogenic species. The next step is therefore to explore the relationships between host-microbial communities (microbiota) and microbial members with potential pathogenic behavior (pathobiota) in a realistic ecological context. In the present study, we investigated such relationships within root and leaf associated bacterial communities of 163 ecologically contrasted Arabidopsis thaliana populations sampled across two seasons in South-West of France. In agreement with the theory of the invasion paradox, we observed a significant humped-back relationship between microbiota and pathobiota -diversity that was robust between both seasons and plant organs. In most populations, we also observed a strong dynamics of microbiota composition between seasons. Accordingly, the potential pathobiota composition was explained by combinations of season-specific microbiota OTUs. This result suggests that the potential biomarkers controlling pathogens invasion are highly dynamic.

microbiology↗