Transcriptional responses of Solanum lycopersicum to three distinct parasites reveal host hubs and networks underlying parasitic successes
Authors: Truch, J., Jaouannet, M., Da Rocha, M., Kulhanek-Fontanille, E., Van Ghelder, C., Rancurel, C., Migliore, O., Pere, A., Jaubert, S., Coustau, C., Galiana, E., Favery, B.
The study used transcriptomic profiling to compare tomato (Solanum lycopersicum) responses to three evolutionarily distant pathogens—nematodes, aphids, and oomycetes—during compatible interactions, identifying differentially expressed genes and key host hubs. Integrating public datasets and performing co‑expression and GO enrichment analyses, the authors mapped shared dysregulation clusters and employed Arabidopsis interactome data to place tomato candidates within broader networks, highlighting potential targets for multi‑pathogen resistance.
The study generated the first single‑nucleus RNA‑sequencing dataset of tomato (Solanum lycopersicum) roots colonized by the arbuscular mycorrhizal fungus Rhizophagus irregularis, revealing distinct transcriptional programs in epidermal and cortical cells across stages of arbuscule development. Using unsupervised subclustering and a Motif‑Informed Network Inference (MINI‑EX) approach, the authors identified candidate transcription factors that may coordinate cell‑cycle reactivation and nutrient integration during symbiosis, offering a resource for future functional genetics.
The study assessed three savory essential oil–based formulations for controlling early blight caused by Alternaria solani in tomato, finding that formulation CC2020 most effectively reduced disease severity in both in vitro and greenhouse trials. CC2020 also helped maintain tomato fruit vitamin C levels and lowered fungal melanin production, indicating dual benefits for disease suppression and fruit quality.
The study created a system that blocks root‑mediated signaling between wheat varieties in a varietal mixture and used transcriptomic and metabolomic profiling to reveal that root chemical interactions drive reduced susceptibility to Septoria tritici blotch, with phenolic compounds emerging as key mediators. Disruption of these root signals eliminates both the disease resistance phenotype and the associated molecular reprogramming.
The study identified the poplar homolog of Arabidopsis HDG11 and generated transgenic poplar hybrids overexpressing PtaHDG11. Constitutive expression conferred markedly improved drought tolerance, as evidenced by higher leaf water content, reduced oxidative damage, up‑regulation of antioxidant genes, and greater post‑stress biomass, while also causing a glabrous phenotype. These results highlight PtaHDG11 as a promising target for breeding drought‑resilient trees.
A novel pathosystem between Aeschynomene evenia and Aphanomyces euteiches reveals new immune components in quantitative legume root-rot resistance.
Authors: Baker, M., Martinez, Y., Keller, J., Sarrette, B., Pervent, M., Libourel, C., Le Ru, A., Bonhomme, M., Gough, C., Castel, B., ARRIGHI, J.-F., Jacquet, C.
The study establishes Aeschynomene evenia as a new model for dissecting legume immunity against the soilborne pathogen Aphanomyces euteiches and its relationship with Nod factor-independent symbiosis. Quantitative resistance was assessed through inoculation assays, phenotypic and cytological analyses, and RNA‑seq identified thousands of differentially expressed genes, highlighting immune signaling and specialized metabolism, with mutant analysis confirming dual‑function kinases that modulate resistance. Comparative transcriptomics with Medicago truncatula revealed conserved and unique immune responses, positioning the A. evenia–A. euteiches system as a valuable platform for exploring quantitative resistance and symbiosis integration.
The study characterizes the chloroplast‑localized protein AT4G33780 in Arabidopsis thaliana using CRISPR/Cas9 knockout and overexpression lines, revealing tissue‑specific expression and context‑dependent effects on seed germination, seedling growth, vegetative development, and root responses to nickel stress. Integrated transcriptomic (RNA‑seq) and untargeted metabolomic analyses show extensive transcriptional reprogramming—especially of cell‑wall genes—and altered central energy metabolism, indicating AT4G33780 coordinates metabolic state with developmental regulation rather than controlling single pathways.
The study examined the roles of AtKUP2, AtKUP6, AtKUP8, and GORK potassium transport proteins in guard cell function by performing gas-exchange measurements on mature Arabidopsis leaves. Loss of KUP2/6/8 reduced stomatal conductance, whereas a GORK loss‑of‑function mutant showed increased conductance, yet the magnitude of light‑ and ABA‑induced transpiration changes remained similar across genotypes, suggesting a limited dynamic range for rapid stomatal movements that relies on small ionic osmolytes.
The authors performed a genome-wide analysis of 53 CCCH zinc‑finger genes in pearl millet, identified seven stress‑responsive members and demonstrated that overexpressing PgC3H50 in Arabidopsis enhances drought and salt tolerance. They showed that the ABA‑responsive transcription factor PgAREB1 directly binds the PgC3H50 promoter, activating its expression, as confirmed by yeast one‑hybrid, dual‑luciferase and EMSA assays, defining a new PgAREB1‑PgC3H50 regulatory module.
The study reveals that REMORIN protein evolution is primarily driven by diversification of their conserved C-terminal domain, defining four major clades. Structural bioinformatics predicts a common membrane‑binding interface with diverse curvatures and lengths, and suggests that some REMs can form C‑terminal‑mediated oligomers, adding complexity to membrane organization.