Biology subjects

Malnoy, M.

Publications and source records attributed to Malnoy, M..

3 recordsLinked to original sources

bioRxiv2025

Developing the Grapevine Hydric Stress Atlas: A Meta-Analysis Resource for Exploring transcriptome Responses to Drought

Climate change poses a significant threat to agriculture, particularly in regions where increased drought periods, abnormal heat, and intensified pest pressure threaten crop productivity. Viticulture, as one of the most economically important crops, is highly vulnerable to these challenges. Understanding the molecular mechanisms underlying drought responses in grapevines is essential for developing innovative molecular breeding strategies aimed at enhancing drought tolerance, improving cultivar resilience, and promoting agricultural sustainability. In this context, transcriptomic meta-analyses have proven valuable for uncovering global regulatory trends, gene co-expression networks and conserved biological responses across diverse conditions. As part of this study, 1107 public transcriptomic datasets from Illumina (631 runs) and ABI SOLID (476 runs) platforms were searched, reclassified and reanalyzed in the latest T2T genome assembly, in order to construct condition, cultivar and tissue-specific gene expression atlases associated with drought stress in grapevine. To facilitate exploration of this data, a web-based application, the Hydric Stress Atlas App (https://plantaeviz.tomsbiolab.com/vitviz/hydric_atlas/), was developed, as part of the Vitis module within the PlantaeViz platform. Together with this tool, we generated a whole-genome co-expression network using the same datasets (https://plantaeviz.tomsbiolab.com/vitviz/networks/non_agg_gcns/T2T/hydric_stress_TI/). This water stress condition-dependent GCN allows to explore and visualize gene co-expression relationships related to stress and identify network hubs holding novel drought stress regulators. We manually curated experimental metadata, and enabled the classification of transcriptomic data by cultivar, tissue, and drought tolerance. Finally, candidate genes associated with drought tolerance were identified via network topology analysis. These genes can be further used as molecular markers, or characterized via gene editing or cisgenesis, providing insights into their molecular roles in drought tolerance. This resource contributes to a deeper understanding of grapevine drought responses, offering a pathway for sustainable viticulture and innovative biotechnological solutions to address climate-related challenges.

plant biology↗

bioRxiv2021

Detection of an unstable minor QTL linked to fire blight resistance on linkage group 16 of Malus fusca

ObjectiveErwinia amylovora causes fire blight disease in Malus. A strong resistance QTL (Mfu10) was previously detected on linkage group 10 of Malus fusca accession MAL0045, using several strains of the bacterium. As no strain capable of breaking the resistance of MAL0045 has been found, it was hypothesized that a second resistance factor contributes to the fire blight resistance of MAL0045. However, to date, no minor locus has been detected with previously published strains of the bacterium. We detected a minor QTL only on a subset of a population following inoculation with strain Ea1038, which heterologously expresses an effector in a derivative of isolate Ea3049. Two genetic maps of MAL0045, one scarce, the other dense with markers, were used for QTL analyses. ResultsMfu10 was detected on LG10 with Ea1038, as was previously with Ea3049. Although no other QTLs of significant LOD was previously detected in other linkage groups with Ea3049, a QTL of significant LOD was detected on LG16 (Mfu16) after inoculation of a subset of 76 individuals with Ea1038, but only using the dense genetic map. Mfu16 improved the effect of Mfu10. However, when the number of individuals inoculated with Ea1038 was increased to 121, Mfu16 was no longer detected in the dense genetic map. We hypothesize some factors, which might be responsible for the instability of this QTL.

genetics↗

bioRxiv2021

The Arabidopsis pattern recognition receptor EFR enhances fire blight resistance in apple

Fire blight disease, caused by the bacterium Erwinia amylovora (E. amylovora), is responsible for substantial losses in cultivated apple worldwide. An important mechanism of plant immunity is based on the recognition of conserved microbial molecules, named pathogen- or microbe-associated molecular patterns (PAMPs or MAMPs), through pattern recognition receptors (PRRs), leading to pattern-triggered immunity (PTI). The interspecies transfer of PRRs represents a promising strategy to engineer broad spectrum and durable disease resistance in crops. EFR, the Arabidopsis thaliana PRR for the PAMP elf18 derived from the elongation factor thermal unstable (EF-Tu) proved to be effective in improving bacterial resistance when expressed into Solanaceae and other plant species. In this study, we tested whether EFR can affect the interaction of apple with E. amylovora by its ectopic expression in the susceptible apple rootstock M.26. Stable EFR expression led to the activation of PAMP-triggered immune response in apple leaves upon treatment with supernatant of E. amylovora, as measured by production of reactive oxygen species and the induction of known defense genes. The amount of tissue necrosis associated with E. amylovora infection was significantly reduced in the EFR transgenic rootstock compared to the wild-type. Our results show that the expression of EFR in apple rootstock may be a valuable biotechnology strategy to improve the resistance of apple to fire blight.

plant biology↗