Genetius

The study demonstrates that the Nicotiana benthamiana NLR Roq1, previously known to recognize the XopQ/HopQ1/RipB effector family, also detects the structurally distinct HopAG1 effector, leading to reduced bacterial growth and disease symptoms. Roq1-HopAG1 interaction was confirmed by co‑immunoprecipitation and attributed to the Nudix domain of HopAG1 binding a similar receptor interface as XopQ, suggesting broader effector recognition potential for Roq1 and other TNLs.

The study identifies the extended NT‑C2 domain of Plastid Movement Impaired 1 (PMI1) as the main membrane‑binding module that interacts with PI4P and PI(4,5)P2, requiring basic residues for plasma‑membrane association. Calcium binding by the NT‑C2 domain modulates its phosphoinositide preference, and cytosolic Ca2+ depletion blocks blue‑light‑induced PMI1 redistribution, indicating that both the NT‑C2 domain and adjacent intrinsically disordered regions are essential for PMI1’s role in chloroplast movement.

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 authors used a bottom‑up thermodynamic modelling framework to investigate how plants decode calcium signals, starting from Ca2+ binding to EF‑hand proteins and extending to higher‑order decoding modules. They identified six universal Ca2+-decoding modules that can explain variations in calcium sensitivity among kinases and provide a theoretical basis for interpreting calcium signal amplitude and frequency in plant cells.

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 demonstrates that infiltrating Nicotiana benthamiana leaves with specific nopaline-type Agrobacterium tumefaciens strains dramatically increases local glandular trichome density within 15 days, an effect linked to the bacterial trans-zeatin synthase (tzs) gene that produces the cytokine trans‑zeatin. This simple Agrobacterium‑mediated approach enables direct comparison of high‑density trichome regions with adjacent isogenic tissue on the same leaf.

The study reveals that rice perceives Xanthomonas oryzae pv. oryzae outer membrane vesicles through a rapid calcium signal that triggers plasma‑membrane nanodomain formation and the re‑organisation of defence‑related proteins, establishing an early immune response. Without this Ca2+ signal, OMVs are not recognized and immunity is weakened.

Infiltration of Nicotiana benthamiana leaves with Agrobacterium tumefaciens strain GV3101 carrying the pMP90 Ti plasmid triggers de novo formation of capitate glandular trichomes and elevates acyl‑sugar production, an effect absent with other strains. The responsible factor is the trans‑zeatin synthase (tzs) gene on pMP90, and exogenous application of cytokinins (trans‑zeatin or benzylaminopurine) alone can reproduce trichome induction, linking cytokinin signaling to trichome development. The study highlights that Agrobacterium-mediated transient assays can have unintended developmental and biochemical impacts, recommending strain testing to mitigate such effects.

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 systematically examines sources of variability in Agrobacterium tumefaciens-mediated transient expression in Nicotiana benthamiana, analyzing a large dataset of 1,915 plants collected over three years. It demonstrates that normalization methods must be validated for each experimental context and provides a statistical model and power analysis framework to determine appropriate sample sizes for detecting specific effect sizes, offering practical guidelines to improve reproducibility in quantitative plant and synthetic biology studies.