Root-Suppressed Phenotype of Tomato Rs Mutant is Seemingly Related to Expression of Root-Meristem-Specific Sulfotransferases
Authors: Kumari, A., Gupta, P., Santisree, P., Pamei, I., Valluri,, S., Sharma, K., Venkateswara Rao, K., Shukla, S., Nama, S., Sreelakshmi, Y., Sharma, R.
The study characterizes a radiation‑induced root‑suppressed (Rs) mutant in tomato that displays dwarfism and pleiotropic defects in leaves, flowers, and fruits. Metabolite profiling and rescue with H2S donors implicate disrupted sulfur metabolism, and whole‑genome sequencing identifies promoter mutations in two root‑meristem‑specific sulfotransferase genes as likely contributors to the root phenotype.
The study shows that nitrogen deficiency markedly elevates the exudation of the triterpenoid Solanoeclepin A (SolA) from tomato roots, a process that requires non‑sterile soil and involves the rhizosphere microbiota. Transient silencing of two candidate biosynthetic genes (CYP749A19 and CYP749A20) reduced SolA levels and impaired recruitment of beneficial Massilia spp., which promote plant growth under nitrogen limitation, indicating that SolA acts as a microbe‑mediated recruitment signal that was co‑opted by cyst nematodes.
The study examined how dual‑purpose hemp (Cannabis sativa) adjusts to different phosphate levels, showing that flower biomass is maintained unless phosphate is completely removed. Integrated physiological measurements and transcriptomic profiling revealed that phosphate is reallocated to flowers via glycolytic bypasses and organic phosphate release, while key regulatory genes followed expected patterns but did not suppress uptake at high phosphate, leading to nitrate depletion that limits growth.
The study identified a heat‑responsive exon‑skipping event in the basic Helix‑Loop‑Helix domain of the transcription factor PIF4, which reduces PIF4 activity and promotes photomorphogenic traits in etiolated seedlings. This reveals a novel post‑transcriptional mechanism by which plants modulate PIF4 function during heat stress.
In vivo binding by Arabidopsis SPLICING FACTOR 1 shifts 3' splice site choice, regulating circadian rhythms and immunity in plants
Authors: Agrofoglio, Y. C., Iglesias, M. J., de Leone, M. J., Hernando, C. E., Lewinski, M., Torres, S. B., Contino, G., Yanovsky, M. J., Staiger, D., Mateos, J. L.
The study characterizes the plant spliceosomal protein AtSF1 in Arabidopsis thaliana, using iCLIP and RNA‑seq to map its in vivo branch point binding sites and demonstrate that loss of AtSF1 causes widespread 3' splice‑site mis‑selection. Structural comparison reveals a plant‑specific domain architecture, and the identified AtSF1 targets are enriched for circadian and defense genes, linking splicing regulation to timing and immunity.
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 identifies MtFTb1 and MtFTb2 as essential, redundant regulators of long‑day flowering in the legume Medicago truncatula, demonstrating that they are required for up‑regulating MtFTa1 under vernalised long‑day conditions. Using CRISPR/Cas9‑generated single and double mutants, the authors show that double mutants are specifically delayed in flowering under long days while retaining vernalization responsiveness, and transcriptomic analyses reveal that MtFTb1/2 activate MADS‑box genes and other flowering regulators.
Evolution of HMA-integrated tandem kinases accompanied by expansion of target pathogens
Authors: Asuke, S., Tagle, A. G., Hyon, G.-S., Koizumi, S., Murakami, T., Horie, A., Niwamoto, D., Katayama, E., Shibata, M., Takahashi, Y., Islam, M. T., Matsuoka, Y., Yamaji, N., Shimizu, M., Terauchi, R., Hisano, H., Sato, K., Tosa, Y.
The study cloned the resistance genes Rmo2 and Rwt7 from barley and wheat, revealing them as orthologous tandem kinase proteins (TKPs) with an N‑terminal heavy metal‑associated (HMA) domain. Domain‑swapping experiments indicated that the HMA domain dictates effector specificity, supporting a model of TKP diversification into paralogs and orthologs that recognize distinct pathogen effectors.
Mutations in the plastid division gene PARC6 and the granule initiation gene BGC1 were combined to generate wheat plants with dramatically enlarged A-type starch granules, some exceeding 50 µm, without affecting plant growth, grain size, or overall starch content. The parc6 bgc1 double mutant was evaluated in both glasshouse and field trials, and the giant granules displayed altered viscosity and pasting temperature, offering novel functional properties for food and industrial applications.
Using ten Phaeodactylum tricornutum mutant strains with graded constitutive Lhcx1 expression, the study links NPQ induction under high light to physiological outcomes (oxidized QA, increased cyclic electron flow) and extensive transcriptomic reprogramming, affecting nearly half the genome. The approach demonstrates that higher NPQ mitigates PSII damage, boosts ATP production for repair, and drives distinct gene regulatory networks, providing a model framework for dissecting photosynthetic and gene expression integration.