Quantitative trait locus mapping of root exudate metabolome in a Solanum lycopersicum Moneymaker x S. pimpinellifolium RIL population and their putative links to rhizosphere microbiome
Authors: Kim, B., Kramer, G., Leite, M. F. A., Snoek, B. L., Zancarini, A., Bouwmeester, H.
The study used untargeted metabolomics and QTL mapping in a tomato recombinant inbred line population to characterize root exudate composition and identify genetic loci controlling specific metabolites. It reveals domestication-driven changes in exudate profiles and links metabolic QTLs with previously reported microbial QTLs, suggesting a genetic basis for shaping the root microbiome.
The study identified a critical two‑week window of elevated maternal temperature during weeks 4–5 after flowering that delays dormancy release in weedy rice seeds. Controlled‑environment and field transplant experiments showed that this late‑reproductive‑stage heat exposure postpones germination after after‑ripening, providing insight for predicting seed behavior and improving weed management strategies.
The study examined DNA methylation dynamics in Arabidopsis thaliana shoots and roots under heat, phosphate deficiency, and combined stress using whole-genome bisulfite sequencing, small RNA‑seq, and RNA‑seq. Distinct stress‑specific methylation patterns were identified, with heat and combined stress causing CHH hypomethylation, phosphate deficiency causing hyper‑ and hypomethylation in shoots and roots respectively, and the combined stress exhibiting a unique signature independent of additive effects. Methylation changes were concentrated in transposable elements and regulatory regions, implicating RdDM and CMT2 pathways and suggesting a role in chromatin accessibility rather than direct transcriptional control.
The study reveals that heat tolerance of meiotic division in Arabidopsis thaliana depends on sustained translation of cell‑cycle genes mediated by the protein TAM, which forms specialized condensates under high temperature. Natural variation was used to identify heat‑sensitive and heat‑tolerant TAM alleles, and boosting TAM translation with complementary peptides rescued heat‑induced meiotic defects, highlighting a potential mechanism driving polyploidisation under climate stress.
Thermotolerant pollen tube growth is controlled by RALF signaling.
Authors: Althiab Almasaud, R., Ouonkap Yimga, S. V., Ingram, J., Oseguera, Y., Alkassem Alosman, M., Travis, C., Henry, A., Medina, M., Oulhen, N., Wessel, G. M., Delong, A., Pease, J., DaSilva, N., Johnson, M.
The study investigates the molecular basis of heat‑tolerant pollen tube growth in tomato (Solanum lycopersicum) by comparing thermotolerant and sensitive cultivars. Using live imaging, transcriptomics, proteomics, and genetics, the authors identified the Rapid Alkalinization Factor (RALF) signaling pathway as a key regulator of pollen tube integrity under high temperature, with loss of a specific RALF peptide enhancing tube integrity in a thermotolerant cultivar.
Daily Heat Stress Induces Accumulation of Non-functional PSII-LHCII and Donor-side Limitation of PSI via Downregulation of the Cyt bf Complex in Arabidopsis thaliana
The study examined the impact of daily moderate heat stress (38 °C for 4 h) on Arabidopsis thaliana, revealing altered thylakoid ultrastructure and structurally intact but functionally impaired PSII‑LHCII complexes. A pronounced reduction in cytochrome b6f content limited PSI on the donor side, suggesting that Cyt b6f down‑regulation serves as an acclimation mechanism that protects PSI at the expense of overall photosynthetic efficiency.
Discovery of tomato UDP-glucosyltransferases involved in bioactive jasmonate homeostasis using limited proteolysis-coupled mass spectrometry
Authors: Venegas-Molina, J., Mohnike, L., Selma Garcia, S., Janssens, H., Colembie, R., Kimpe, I., Jaramillo-Madrid, A. C., Lacchini, E., Winne, J. M., Van Damme, P., Feussner, I., Goossens, A., Sola, K.
The study applied limited proteolysis‑coupled mass spectrometry (LiP‑MS) to map JA‑protein interactions, validating known JA binders and uncovering novel candidates, including several UDP‑glucuronosyltransferases (UGTs). Functional omics, biochemical, enzymatic, and structural analyses demonstrated that two tomato UGTs glucosylate jasmonic acid, revealing a previously missing step in JA catabolism.
The study investigated metabolic responses of kale (Brassica oleracea) grown under simulated microgravity using a 2-D clinostat versus normal gravity conditions. LC‑MS data were analyzed with multivariate tools such as PCA and volcano plots to identify gravity‑related metabolic adaptations and potential molecular markers for spaceflight crop health.
The study assessed the impact of adding mammalian growth factors and cytokines to transformation media on CRISPR‑Cas9–mediated genome editing in six tomato (Solanum lycopersicum) accessions with varying regeneration capacities. Over three years, supplementation with these factors significantly increased regeneration rates and the production of stable secondary transgenic lines, especially in recalcitrant genotypes.
The researchers created tomato lines overexpressing the autophagy gene SlATG8f and evaluated their performance under high-temperature stress. qRT‑PCR and physiological measurements revealed that SlATG8f overexpression enhances expression of autophagy‑related and heat‑shock protein genes, accelerates fruit ripening, and improves fruit quality under heat stress.