DECREASE IN DNA METHYLATION 1-mediated epigenetic regulation maintains gene expression balance required for heterosis in Arabidopsis thaliana
Authors: Matsuo, K., Wu, R., Yonechi, H., Murakami, T., Takahashi, S., Kamio, A., Akter, M. A., Kamiya, Y., Nishimura, K., Matsuura, T., Tonosaki, K., Shimizu, M., Ikeda, Y., Kobayashi, H., Seki, M., Dennis, E. S., Fujimoto, R.
The study demonstrates that the chromatin remodeler DDM1 is essential for biomass heterosis in Arabidopsis thaliana hybrids, as loss of DDM1 function leads to reduced rosette growth and extensive genotype‑specific transcriptomic and DNA methylation changes. Whole‑genome bisulfite sequencing revealed widespread hypomethylation in ddm1 mutants, while salicylic acid levels were found unrelated to heterosis, indicating that epigenetic divergence, rather than SA signaling, underpins hybrid vigor.
The study shows that the membrane lipids PI4P, PI(4,5)P2, and phosphatidylserine have distinct spatial and temporal dynamics during lateral root primordium formation in Arabidopsis thaliana, with PI4P acting as a stable basal lipid, PI(4,5)P2 serving as a negative regulator of initiation, and phosphatidylserine increasing after founder cell activation. Using live-cell biosensors, genetic mutants, and an inducible PI(4,5)P2 depletion system, the authors demonstrate that reducing PI(4,5)P2 enhances lateral root initiation and development.
Authors: Ramires, M. J., Netherer, S., Schebeck, M., Hummel, K., Schlosser, S., Razzazi-Fazeli, E., Ertl, R., Ahmad, M., Espinosa-Ruiz, A., Carrera, E., Arc, E., Martinez-Godoy, M. A., Banos, J., Caballero, T., Ledermann, T., van Loo, M., Trujillo-Moya, C.
Using a controlled field experiment on clonal 35‑year‑old Norway spruce trees, the study examined molecular defense responses to Ips typographus attacks. A multi‑omics approach revealed rapid local increases in jasmonic acid and other phytohormones, leading to differential expression of up to 1,900 genes and corresponding proteomic and metabolomic changes that elevated deterrent compounds such as phenolic aglycones, diterpene resin acids, terpenes, and lignin.
The study applied a progressive, sublethal drought treatment to Arabidopsis thaliana, collecting time‑resolved phenotypic and transcriptomic data. Machine‑learning analysis revealed distinct drought stages driven by multiple overlapping transcriptional programs that intersect with plant aging, and identified high‑explanatory‑power transcripts as biomarkers rather than causal agents.
Salt stress strongly suppresses root growth in Festuca rubra while sparing shoot development. Transcriptome profiling identified over 68,000 differentially expressed genes, with up‑regulated genes enriched in methionine, melatonin, and suberin biosynthesis and down‑regulated genes involved in gibberellin, ABA, and sugar signaling, indicating extensive hormonal and metabolic reprogramming. Paradoxical regulation of gibberellin and ethylene pathways suggests a finely tuned balance between growth and stress responses.
The study examined how single and repeated mechanical disturbances (whole‑pot drops) affect leaf folding in Mimosa pudica, using chlorophyll fluorescence to track photosystem II efficiency and transcriptome profiling to identify responsive genes. A single drop mainly up‑regulated flavonoid biosynthesis genes, whereas multiple drops triggered broader biotic and abiotic stress pathways, indicating a shift in the plant’s gene regulatory network under repeated stress.
Enhancement of Arabidopsis growth by Enterobacter sp. SA187 under elevated CO2 is dependent on ethylene signalling activation and primary metabolism reprogramming
Authors: Ilyas, A., Mauve, C., Pateyron, S., Paysant-Le Roux, C., Bigeard, J., Hodges, M., de Zelicourt, A.
The study shows that inoculating Arabidopsis thaliana with the plant‑growth‑promoting bacterium Enterobacter sp. SA187 markedly boosts root and shoot biomass under elevated CO₂, accompanied by altered nitrogen and carbon content and reshaped phytohormone signaling. Transcriptomic and metabolomic analyses reveal activation of salicylic acid, jasmonic acid, and ethylene pathways and enhanced primary metabolism, while the ethylene‑insensitive ein2‑1 mutant demonstrates that the growth benefits are ethylene‑dependent.
The study examined soybean (Glycine max) responses to simultaneous drought and Asian soybean rust infection using combined transcriptomic and metabolomic analyses. Weighted Gene Co-expression Network Analysis identified stress-specific gene modules linked to metabolites, while Copula Graphical Models uncovered sparse, condition‑specific networks, revealing distinct molecular signatures for each stress without overlapping genes or metabolites. The integrative approach underscores a hierarchical, modular defense architecture and suggests targets for breeding multi‑stress resilient soybeans.
Using integrated metabolomics, fluxomics, and proteomics, the study shows that Bamboo mosaic virus infection in Nicotiana benthamiana redirects carbon flux toward glycolysis and the TCA cycle, enhancing mitochondrial metabolism. Silencing the mitochondrial NAD⁺-dependent malic enzyme 1 disrupts cytoplasmic NADH/NAD⁺ balance and alters defense gene expression, indicating that mitochondrial redox regulation is crucial for antiviral defense.
Authors: Orosz, J., Lin, E. X., Torres Ascurra, Y. C., Kappes, M., Lindsay, P. L., Bashyal, S., Everett, H., Gautam, C. K., Jackson, D., Mueller, L. M.
The study identifies the pseudokinase CRN in Medicago truncatula as a regulator of inflorescence meristem branching and a negative modulator of root interactions with arbuscular mycorrhizal (AM) fungi, operating partially independently of the AM autoregulation CLE peptide MtCLE53. Transcriptomic profiling of crn mutant roots reveals disruptions in nutrient, symbiosis, and stress signaling pathways, highlighting the multifaceted role of MtCRN in plant development and environmental interactions.