Genetius

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 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 study shows that Arabidopsis root tips adapt to hypoxia by increasing H3K4me3 levels, linked to the inhibition of group 7 demethylases (KDM7s). Genetic loss of KDM7s mimics hypoxic conditions, activating genes that sustain meristem survival, suggesting KDM7s act as root‑specific oxygen sensors that prime epigenetic tolerance mechanisms.

The authors generated a high‑resolution 1.45‑billion‑contact Micro‑C map for cultivated tomato (Solanum lycopersicum), identifying ~4,600 long‑range chromatin loops that fall into promoter‑centered and Polycomb/heterochromatin‑associated classes. Comparative Micro‑C in wild tomatoes showed conserved loop anchors despite sequence turnover, and integration with transcriptomics revealed that promoter‑anchored loops can either activate or repress gene expression depending on the chromatin state of distal anchors.

The study reveals that the methyl‑CpG‑binding domain protein MBD8 interacts with the histone demethylase LDL2 to facilitate removal of H3K4me1 and transcriptional repression downstream of H3K9me2 in Arabidopsis. MBD8 binds GC‑poor DNA independently of cytosine methylation and stabilizes LDL2 protein levels, indicating a broader role for MBD proteins beyond methyl‑DNA recognition.

The study conducted a genome-wide characterization of 247 lectin genes in tomato, revealing diverse domain architectures and evolutionary patterns shaped by whole-genome and small-scale duplications. Functional assays using virus-induced gene silencing demonstrated that two GNA-type chimerolectins act as negative regulators of immunity, with silencing enhancing resistance to Ralstonia solanacearum. These results underscore the structural innovation and immune-regulatory roles of lectin genes, offering targets for disease‑resistant tomato breeding.

The study examined how increasing copper concentrations affect root tip cells of Solanum lycopersicum, revealing that mitochondria are the first organelles to exhibit fragmentation, depolarization, and ROS accumulation, which trigger stress signaling cascades. Copper exposure also caused pronounced nuclear alterations, including chromatin condensation marked by reduced H3K4me3, nuclear shrinkage, and eventual cell death, highlighting chromatin remodeling as a key indicator of copper toxicity.

Using transparent root apex cells of Solanum lycopersicum, the study employed live‑cell fluorescence imaging, immunostaining, and super‑resolution microscopy to map the sequential collapse of organelles under lidocaine anesthesia. It reveals that mitochondria, lysosomes, vesicle trafficking, and especially the nucleus undergo time‑dependent damage, with reversible effects up to four hours but irreversible nuclear degradation and programmed cell death beyond that, highlighting potential protective strategies.

The study used chemically induced effector-triggered immunity combined with single-cell transcriptomics to map immune responses across all leaf cell types in Arabidopsis, revealing that while a core defense program is universally activated, individual cell types deploy distinct transcriptional modules. Functional assays showed that epidermis‑specific transcriptional regulators are essential for preventing pathogen penetration, indicating a spatial division of immune functions within the leaf.