Arabidopsis lines with modified ascorbate concentrations reveal a link between ascorbate and auxin biosynthesis
Authors: Fenech, M., Zulian, V., Moya-Cuevas, J., Arnaud, D., Morilla, I., Smirnoff, N., Botella, M. A., Stepanova, A. N., Alonso, J. M., Martin-Pizarro, C., Amorim-Silva, V.
The study used Arabidopsis thaliana mutants with low (vtc2, vtc4) and high (vtc2/OE-VTC2) ascorbate levels to examine how ascorbate concentration affects gene expression and cellular homeostasis. Transcriptomic analysis revealed that altered ascorbate levels modulate defense and stress pathways, and that TAA1/TAR2‑mediated auxin biosynthesis is required for coping with elevated ascorbate in a light‑dependent manner.
Integrative analysis of plant responses to a combination of water deficit, heat stress and eCO2 reveals a role for OST1 and SLAH3 in regulating stomatal responses
Authors: Pelaez-Vico, M. A., Sinha, R., Ghani, A., Lopez-Climent, M. F., Joshi, T., Fritschi, F. B., Zandalinas, S. I., Mittler, R.
The study examined how Arabidopsis thaliana integrates physiological, genetic, hormonal, and transcriptomic responses to combined water deficit, heat stress, and elevated CO2. Results show that stomatal aperture under these complex stress combinations is governed by a specific set of regulators, including nitric oxide, OPEN STOMATA 1, and the SLAH3 anion channel, distinct from those active under simpler stress conditions. This reveals a hierarchical stomatal stress code that could inform future research on plant resilience to global change.
Transcriptomic and physiological responses of soybean plants subjected to a combination of water deficit and heat stress under field conditions
Authors: Sinha, R., Pelaez-Vico, M. A., Dhakal, S., Ghani, A., Myers, R., Verma, M., Shostak, B., Ogden, A., Krueger, C. B., Costa Netto, J. R., Zandalinas, S. I., Joshi, T., Fritschi, F. B., Mittler, R.
A two‑year field study examined how soybean (Glycine max) vegetative and reproductive tissues respond transcriptionally and physiologically to water deficit, heat, and their combination. The field‑grown plants showed distinct transcriptomic patterns compared with controlled‑environment studies, especially under single stresses, while differential leaf‑pod transpiration observed in growth chambers was also present in the field. The generated transcriptomic dataset highlights the importance of field‑based omics for understanding crop stress responses.
Comparative multi-omics profiling of Gossypium hirsutum and Gossypium barbadense fibers at high temporal resolution reveals key differences in polysaccharide composition and associated glycosyltransferases
Authors: Swaminathan, S., Lee, Y., Grover, C. E., DeTemple, M. F., Mugisha, A. S., Sichterman, L. E., Yang, P., Xie, J., Wendel, J. F., Szymanski, D. B., Zabotina, O. A.
The study performed daily large-scale glycome, transcriptome, and proteome profiling of developing fibers from the two cultivated cotton species, Gossypium barbadense and G. hirsutum, across primary and secondary cell wall stages. It identified delayed cellulose accumulation and distinct compositions of xyloglucans, homogalacturonans, rhamnogalacturonan‑I, and heteroxylans in G. barbadense, along with higher expression of specific glycosyltransferases and expansins, suggesting these molecular differences underlie the superior fiber length and strength of G. barbadense.
The study evaluated how acute heat stress affects early-stage rice seedlings, identifying a critical temperature threshold that impairs growth. Transcriptomic profiling of shoots and roots revealed ethylene‑responsive factors (ERFs) as central regulators, with ethylene and jasmonic acid acting upstream, and pre‑treatment with these hormones mitigated heat damage. These findings highlight ERF‑hormone interaction networks as targets for improving rice heat resilience.
Using the Euphorbia peplus genome, the authors performed organ‑specific transcriptomic profiling of the cyathium and combined it with gene phylogenies and dN/dS analysis to investigate floral‑development gene families. They found distinct SEP1 paralog expression, lack of E‑class gene duplications typical of other pseudanthia, and divergent expression patterns for CRC, UFO, LFY, AP3, and PI, suggesting unique developmental pathways in Euphorbia.
The study shows that heatwaves impair the ability of apple (Malus domestica) to mount ASM‑induced immunity against fire blight and apple scab, leading to a loss of protective gene expression. Transcriptomic analysis revealed a broad suppression of ASM‑regulated defense and other biological processes under high temperature, identifying thermo‑sensitive resistance and susceptibility marker genes. The findings highlight that elevated temperature both weakens plant defenses and creates a more favorable environment for pathogens.
The study identified a major QTL (qDTH3) on chromosome 3 responsible for a 7‑10‑day earlier heading phenotype in the rice line SM93, using QTL‑seq, KASP genotyping, association mapping, and transcriptomic analysis to fine‑map the locus to a 2.53 Mb region and pinpoint candidate genes. SNP markers linked to these genes were proposed as tools for breeding early‑maturing, climate‑resilient rice varieties.
The study compares transcriptional, proteomic, and metabolomic responses of wild‑type Arabidopsis and a cyp71A27 mutant to a plant‑growth‑promoting Pseudomonas fluorescens strain and a pathogenic Burkholderia glumeae strain, revealing distinct reprogramming and an unexpected signaling role for the non‑canonical P450 CYP71A27. Mutant analysis showed that loss of CYP71A27 alters gene and protein regulation, especially during interaction with the PGP bacterium, while having limited impact on root metabolites and exudates.
Arabidopsis root lipid droplets are hubs for membrane homeostasis under heat stress, and triterpenoid synthesis and storage.
Authors: Scholz, P., Dabisch, J., Clews, A. C., Niemeyer, P. W., Vilchez, A. C., Lim, M. S. S., Sun, S., Hembach, L., Dreier, F., Blersch, K., Preuss, L., Bonin, M., Lesch, E., Iwai, Y., Shimada, T., Eirich, J., Finkemeier, I., Gutbrod, K., Doermann, P., Wang, Y., Mullen, R. T., Ischebeck, T.
The study examined how heat stress alters lipid droplet (LD) number and composition in Arabidopsis thaliana roots, revealing degradation of membrane lipids and accumulation of TAGs and LDs. Proteomic and lipidomic analyses of LDs from a specific Arabidopsis mutant identified novel LD-associated proteins, including triterpene biosynthetic enzymes, whose substrates and products also accumulate in LDs, indicating LDs function as both sinks and sources during stress‑induced membrane remodeling and specialized metabolism.