Genetius

A genome-wide association study of 166 Iberian Arabidopsis accessions identified loci, including ABA3 and GA2ox2, that modulate the inhibitory effect of the auxin precursor indole-3-acetamide (IAM) on primary root elongation. Integrating sequence analysis, transcriptomics, 3D protein modeling, and mutant physiology revealed that IAM promotes ABA biosynthesis and signaling, uncovering a novel node of hormone crosstalk.

The study identifies GyrB3 as a novel nuclear factor that interacts with histone deacetylases to regulate transposable element silencing in plants, acting as a suppressor of IBM1 deficiency–induced epigenetic defects. Loss of GyrB3 reduces DNA methylation and increases H3 acetylation at TEs, demonstrating the importance of histone deacetylation for genome stability.

The study identified two subclades of Arabidopsis NUDIX hydrolases that selectively hydrolyze distinct inositol pyrophosphate isomers, with subclade I targeting 4-InsP7 and subclade II targeting 3-InsP7 in a Mg2+-dependent manner. Loss-of-function mutants of subclade II NUDTs displayed disrupted phosphate and iron homeostasis, elevated 1/3-InsP7 levels, and increased resistance to Pseudomonas syringae, revealing roles in nutrient signaling and plant immunity, while cross-kingdom analyses showed conserved PP-InsP‑metabolizing activities.

The study used single‑cell transcriptomics to compare Arabidopsis thaliana leaf cell responses during pattern‑triggered and effector‑triggered immunity, revealing that core defense modules are broadly shared but differ in timing, intensity, and cell‑type specific receptor dynamics. Distinct mesophyll subpopulations showed divergent resilience patterns, and gene regulatory network analysis identified WRKY‑regulated and salicylic‑acid biosynthesis modules, with the cue1-6 mutant confirming robustness of core immune responses while exposing cryptic sucrose‑responsive pathways.

The study reveals that a conserved clade of pentatricopeptide repeat (PPR) genes in Arabidopsis thaliana generates secondary siRNAs that contribute to plant immunity, with these PPR loci undergoing extensive duplication and diversification to create a varied siRNA pool for pathogen defense. This PPR‑siRNA system is proposed as a novel family of defense genes with potential for engineering broad‑spectrum disease resistance.

The study used proximity labeling, co‑immunoprecipitation, and fluorescence microscopy to dissect the protein components and pathways governing distinct extracellular vesicle (EV) subpopulations in Arabidopsis, identifying roles for EXO70 exocyst subunits, RIN4, and VAP27. Mutant analyses revealed that disruptions in exo70 family genes, rin4, rabA2a, scd1, and vap27 reduce EV secretion and increase susceptibility to the fungal pathogen Colletotrichum higginsianum, highlighting EV secretion as a key facet of plant immunity.

The study investigates the conserved EDVID motif in the coiled‑coil domain of plant CC‑NLR immune receptors, revealing its role as a predictor of canonical CC‑NLR function and oligomeric assembly. It identifies a preceding acidic “preEDVID” motif in certain Arabidopsis‑related CC‑NLRs and shows that loss of the EDVID motif defines a distinct NLR subgroup, while acidic residues in the helper NLR NRG1.1 are crucial for cell‑death activity.

The study identifies the RNA‑binding protein AtG3BP1 as a phosphorylation target of MAPKs MPK3, MPK4, and MPK6 at Ser257 in Arabidopsis thaliana and shows that this modification promotes susceptibility to bacterial pathogens, suppresses ROS accumulation and salicylic acid biosynthesis, and maintains stomatal opening. Phospho‑mimic and phospho‑dead mutants reveal that phosphorylation stabilizes AtG3BP1 by preventing proteasomal degradation, highlighting a novel post‑translational control layer in plant immunity.

The study reveals that Arabidopsis actin depolymerization factors (ADF2/3/4) have a nuclear moonlighting role, directly interacting with WRKY transcription factors to regulate immune‑related gene expression. Nuclear, rather than cytosolic, ADFs are essential for defense against both virulent and avirulent Pseudomonas syringae, highlighting a non‑canonical mechanism linking actin dynamics to transcriptional control in plant immunity.

The study shows that the SnRK1 catalytic subunit KIN10 directs tissue-specific growth‑defense programs in Arabidopsis thaliana by reshaping transcriptomes. kin10 knockout mutants exhibit altered root transcription, reduced root growth, and weakened defense against Pseudomonas syringae, whereas KIN10 overexpression activates shoot defense pathways, increasing ROS and salicylic acid signaling at the cost of growth.