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.
A genome-wide survey of the white jute (Corchorus capsularis) identified 34 laccase genes, with expression profiling indicating most are active in phloem and some are up‑regulated during development and under abiotic stress. Comparative analysis with Arabidopsis and reduced expression in a low‑lignin mutant highlighted CcaLAC28 and CcaLAC32 as key candidates for regulating fibre lignification, offering targets for breeding low‑lignin jute varieties.
An ancient alkalinization factor informs Arabidopsis root development
Authors: Xhelilaj, K., von Arx, M., Biermann, D., Parvanov, A., Faiss, N., Monte, I., Klingelhuber, F., Zipfel, C., Timmermans, M., Oecking, C., Gronnier, J.
The study identifies members of the REMORIN protein family as inhibitors of plasma membrane H⁺‑ATPases, leading to extracellular pH alkalinization that modulates cell surface processes such as steroid hormone signaling and coordinates root developmental transitions in Arabidopsis thaliana. This inhibition represents an ancient mechanism predating root evolution, suggesting that extracellular pH patterning has shaped plant morphogenesis.
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 integrated 16 Arabidopsis thaliana whole‑genome bisulfite sequencing datasets from 13 stress experiments using a unified bioinformatic pipeline to map common and stress‑specific DNA methylation changes. Differentially methylated regions varied by stress type and methylation context, with CG DMRs enriched in gene bodies and CHG/CHH DMRs in transposable elements, some of which overlapped loci prone to stable epimutations. Gene ontology and TE enrichment analyses highlighted shared stress pathways and suggest environmental stress can generate heritable epigenetic variation.
The study examined how tomato (Solanum lycopersicum) plants respond hormonally to infection by Pseudomonas syringae pv. tomato DC3000 at two different temperatures, revealing temperature‑dependent expression of marker genes for salicylic acid, jasmonic acid, and abscisic acid pathways, while ethylene‑related genes remained unchanged. These results underscore the intricate interplay between host, pathogen, and environmental conditions in shaping plant defence.
The study compared tissue‑specific transcriptomes of the Australian pitcher plant Cephalotus follicularis with existing data from the Asian pitcher plant Nepenthes gracilis to assess molecular convergence underlying their similar leaf morphologies. Both species showed overlapping gene expression in functionally equivalent tissues and shared transcriptional activation of amino‑acid metabolism and protein synthesis after feeding, while exhibiting distinct regulation of digestive enzyme genes and several cases of combined expression and protein‑sequence convergence in glandular tissues.
The study investigated whether expression of Dormancy-Associated MADS-BOX genes DAM3 and DAM4 inversely correlates with vegetative growth during semi-dormancy induction and breaking in cultivated strawberry. DAM3 and DAM4 expression showed negative correlations with leaf area and petiole length, with DAM4 particularly reflecting growth during dormancy breaking, while no cultivar-specific chill requirement or leaf-type differences were detected. These findings support DAM3 and DAM4 as regulators of semi‑dormancy in Fragaria × ananassa.
Kinase fusion proteins (KFPs) act as immune receptors conferring disease resistance in wheat and barley. The study identified an extended β‑finger motif, a Poaceae-specific feature that arose approximately 98 million years ago, present in functionally confirmed KFPs. These receptor genes are among the most highly expressed members of the KFP family, indicating that high transcript levels are linked to their resistance function.
The study profiled root transcriptomes of Arabidopsis wild type and etr1 gain-of-function (etr1-3) and loss-of-function (etr1-7) mutants under ethylene or ACC treatment, identifying 4,522 ethylene‑responsive transcripts, including 553 that depend on ETR1 activity. ETR1‑dependent genes encompassed ethylene biosynthesis enzymes (ACO2, ACO3) and transcription factors, whose expression was further examined in an ein3eil1 background, revealing that both ETR1 and EIN3/EIL1 pathways regulate parts of the network controlling root hair proliferation and lateral root formation.