The genetic architecture of leaf vein density traits and its importance for photosynthesis in maize
Authors: Coyac-Rodriguez, J. L., Perez-Limon, S., Hernandez-Jaimes, E., Hernandez-Coronado, M., Camo-Escobar, D., Alonso-Nieves, A. L., Ortega-Estrada, M. d. J., Gomez-Capetillo, N., Sawers, R. J., Ortiz-Ramirez, C. H.
Using diverse Mexican maize varieties and a MAGIC population, the study demonstrated that leaf vein density is both variable and plastic, correlating positively with photosynthetic rates for small intermediate veins and increasing under heat in drought-adapted lines. Twelve QTLs linked to vein patterning were identified, highlighting candidate genes for intermediate vein development and shedding light on the evolution of high-efficiency C4 leaf architecture.
The study evaluated how stomatal anatomy and physiological efficiency influence wheat heat tolerance across multi‑environment field trials with 200 genotypes, using early versus delayed sowing to impose temperature stress. Findings revealed a decoupling between anatomical capacity (gsmax) and actual conductance (gs, gse) under heat, plastic shifts toward smaller, denser stomata, and identified 125 QTL linked to stomatal traits, suggesting targets for breeding climate‑resilient wheat.
The authors used a bottom‑up thermodynamic modelling framework to investigate how plants decode calcium signals, starting from Ca2+ binding to EF‑hand proteins and extending to higher‑order decoding modules. They identified six universal Ca2+-decoding modules that can explain variations in calcium sensitivity among kinases and provide a theoretical basis for interpreting calcium signal amplitude and frequency in plant cells.
The authors compiled and standardized published data on Rubisco dark inhibition for 157 flowering plant species, categorizing them into four inhibition levels and analyzing phylogenetic trends. Their meta‑analysis reveals a complex, uneven distribution of inhibition across taxa, suggesting underlying chloroplast microenvironment drivers and providing a new resource for future photosynthesis improvement efforts.
The study examines how ectopic accumulation of methionine in Arabidopsis thaliana leaves, driven by a deregulated AtCGS transgene under a seed‑specific promoter, reshapes metabolism, gene expression, and DNA methylation. High‑methionine lines exhibit increased amino acids and sugars, activation of stress‑hormone pathways, and reduced expression of DNA methyltransferases, while low‑methionine lines show heightened non‑CG methylation without major transcriptional changes. Integrated transcriptomic and methylomic analyses reveal a feedback loop linking sulfur‑carbon metabolism, stress adaptation, and epigenetic regulation.
Characterization of a dominant SmNac-like gene as a candidate for photosensitivity in the fruit peel of eggplant
Authors: Gomis-Cebolla, J., Manrique, S., Arrones, A., Toledo-Tolgar, M. D., Luna, J., Baraja-Fonseca, V., Sanchez-Pascual, J., Gimeno-Paez, E., Plazas, M., Gramazio, P., Vilanova, S., Prohens, J.
The study identified that fruit photosensitivity in eggplant is governed by a single dominant gene, with QTLs clustering at the distal end of chromosome 10 (84.1-87.9 Mb). Bulked segregant analysis sequencing and RNA‑seq highlighted the SmNAC1‑like transcription factor as a likely regulator of anthocyanin accumulation, though no coding sequence mutations were detected, suggesting regulatory control at another level.
Drought-Induced Epigenetic Memory in the cambium of Poplar Trees persists and primes future stress responses
Authors: DUPLAN, A., FENG, Y. Q., LASKAR, G., CAI, B. D., SEGURA, V., DELAUNAY, A., LE JAN, I., DAVIAUD, C., TOUMI, A., LAURANS, F., SOW, M. D., ROGIER, O., POURSAT, P., DURUFLE, H., JORGE, V., SANCHEZ, L., COCHARD, H., ALLONA, I., TOST, J., FICHOT, R., MAURY, S.
The study examined short‑term and transannual drought memory in cambium tissues of two Populus genotypes and four epitypes with modified DNA‑methylation machinery, revealing persistent hormone, transcript, and methylation changes one week after stress relief. Trees previously stressed in Year 1 displayed distinct physiological and molecular responses to a second drought in Year 2, indicating long‑term memory linked to stable CG‑context DNA methylation, with genotype‑dependent differences in plasticity and stability. These findings position the cambium as a reservoir for epigenetic stress memory and suggest exploitable epigenetic variation for tree breeding under drought.
The study identifies and functionally characterizes an acetyl‑CoA:monolignol transferase gene in Populus, showing that its overexpression elevates acetate incorporation into lignin without harming plant growth. Elevated lignin acetylation correlates with gene expression levels and markedly improves biomass pretreatability for biofuel production.
The study compared physiological and transcriptomic responses of poplar trees colonized by the ectomycorrhizal fungi Paxillus involutus or Cenococcum geophilum under normal, drought, and recovery conditions. Cenococcum-colonized plants showed constitutive up‑regulation of heat‑shock proteins, galactinol synthase, and aquaporins and maintained water status and photosynthesis during severe drought, whereas Paxillus colonization promoted growth and nitrogen‑use efficiency and enabled rapid recovery through drought‑induced leaf shedding. These contrasting strategies illustrate species‑specific positions on the growth‑defense trade‑off in ectomycorrhizal symbiosis.
Novel substrate affinity of FaCCR1 and FaCCR1/FaOCT4 expression control the content of medium-chain esters in strawberry fruit
Authors: Roldan-Guerra, F. J., Amorim-Silva, V., Jimenez, J., Mari-Albert, A., Torreblanca, R., Ruiz del Rio, J., Botella, M. A., Granell, A., Sanchez-Sevilla, J. F., Castillejo, C., Amaya, I.
The study identified a major QTL on chromosome 6A that accounts for 40% of variation in medium-chain ester (MCE) levels in strawberry fruit, pinpointing FaCCR1 and FaOCT4 as the causal genes. Functional validation through subcellular localization, transient overexpression, enzymatic assays, and molecular docking demonstrated that FaCCR1 also catalyzes MCE precursor reactions, and a KASP marker in FaOCT4 was developed for breeding fragrant cultivars.