Phosphite (Phi) and phosphate (Pi) share the same root uptake system, but Phi acts as a biostimulant that modulates plant growth and disease resistance in a species‑ and Pi‑dependent manner. In Arabidopsis, Phi induces hypersensitive‑like cell death and enhances resistance to Plectosphaerella cucumerina, while in rice it counteracts Pi‑induced susceptibility to Magnaporthe oryzae and Fusarium fujikuroi, accompanied by extensive transcriptional reprogramming.
The study generated a dataset of 420 sgRNAs targeting promoters, exons, and introns of 137 tomato genes in protoplasts, linking editing efficiency to chromatin accessibility, genomic context, and sequence features. Open chromatin sites showed higher editing rates, while transcriptional activity had little effect, and a subset of guides produced near‑complete editing with microhomology‑mediated deletions. Human‑trained prediction models performed poorly, highlighting the need for plant‑specific guide design tools.
The study examined how elevated atmospheric CO₂ (550 ppm) affects immunity in the C₄ cereal maize (Zea mays L.) by exposing plants grown under ambient and elevated CO₂ to a range of pathogens. Elevated CO₂ increased susceptibility to sugarcane mosaic virus, decreased susceptibility to several bacterial and fungal pathogens, and left susceptibility to others unchanged, with reduced bacterial disease linked to heightened basal immune responses. These findings provide a baseline for future investigations into CO₂‑responsive defense mechanisms in C₄ crops.
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.
The study examined how DNA methylation influences cold stress priming in Arabidopsis thaliana, revealing that primed plants exhibit distinct gene expression and methylation patterns compared to non-primed plants. DNA methylation mutants, especially met1 lacking CG methylation, showed altered cold memory and misregulation of the CBF gene cluster, indicating that methylation ensures transcriptional precision during stress recall.
The study used paired whole‑genome bisulphite sequencing and RNA‑seq on wheat landraces to investigate how DNA methylation patterns change during drought stress, revealing antagonistic trends across cytosine contexts and a key demethylation role for ROS1a family members. Gene‑body methylation correlated positively with expression but negatively with stress‑responsive changes, while drought‑induced hyper‑methylation of specific transposable elements, especially the RLX_famc9 LTR retrotransposon, appears to modulate downstream gene regulation via siRNA precursors.
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 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.
The study mapped the cis‑regulatory landscape of the winter rapeseed cultivar Express617, identifying thousands of novel regulatory elements and characterizing super‑enhancers that are asymmetrically enriched in the Cn subgenome of Brassica napus. An in‑silico pipeline combining population‑level expression data and machine‑learning models revealed that many SE‑associated genes are expressed above predicted levels, and structural variants disrupting SEs lead to reduced gene expression, highlighting their functional importance for gene regulation and breeding.
A genome-wide survey identified 217 EXO70 genes across five kiwifruit (Actinidia spp.) species, classifying them into three subfamilies and nine clades and revealing lineage‑specific expansions, especially in EXO70C, EXO70E, and EXO70H. Functional assays demonstrated that kiwifruit EXO70B1 interacts with the immune hub protein RIN4_1, suggesting a conserved EXO70‑RIN4 module in plant immunity. The study provides a foundational resource for exploring EXO70‑mediated disease resistance in kiwifruit.