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.

Using laser ablation microscopy, the study dissected the role of the first cell row and a contiguous stem cell quorum in the apical notches of germinating Marchantia gemmae, revealing that these cells are essential for meristem activity and that apical notches communicate via auxin‑mediated signals to regulate dominance and regeneration. The findings support a model of intra‑, inter‑, and extra‑notch communication governing meristem formation and maintenance in Marchantia.

Using the bryophyte Physcomitrium patens, the study shows that loss of autophagy enhances auxin‑driven caulonemata differentiation and colony expansion under low nitrogen or imbalanced carbon/nitrogen conditions, accompanied by higher internal IAA, reduced PpPINA expression, and up‑regulated RSL transcription factors. Autophagy appears to suppress auxin‑induced differentiation during nutrient stress, acting as a hub that balances metabolic cues with hormonal signaling.

The abstract proposes that microbial indole-3-acetic acid (IAA) enhances plant thermotolerance by regulating proline metabolism, coordinating early osmoprotective synthesis with later catabolism to support growth and redox balance during heat stress. This regulation is hypothesized to involve integration of auxin perception (HSP90‑TIR1), MAPK signaling (MPK‑IAA8), mitochondrial redox components (SSR1, HSCA2) and interactions with abscisic acid and ethylene, offering a framework for using auxin‑producing microbes to boost heat resilience.

The study characterizes the endophytic fungus Penicillium melinii, isolated from Arabidopsis thaliana roots, as a plant‑growth‑promoting agent that enhances root architecture and biomass across Arabidopsis, quinoa, and tomato. Integrated phenotypic, transcriptomic, and hormonal analyses reveal that the fungus stimulates auxin‑related pathways and modest stress responses, leading to increased tomato yield in field trials, underscoring its value as a model for root development and a sustainable biostimulant.

The study demonstrates that salinity stress induces a photomorphogenic‑like response in dark‑grown Arabidopsis thaliana seedlings, resulting in reduced apical hook curvature and impaired soil emergence. This phenotype is linked to disrupted asymmetric epidermal cell elongation, decreased auxin signaling and PIN3 abundance on the hook’s concave side, repression of BBX28 expression, and loss of a spatial COP1 gradient, highlighting spatial regulation as a key factor in stress‑affected seedling development.

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.

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 elucidates the SPL/NZZ‑dependent regulatory pathway governing megaspore mother cell (MMC) differentiation, revealing that SPL/NZZ directly targets genes and interacts with ovule‑identity MADS‑domain transcription factor complexes. Integration of multi‑omics data with genetic complementation and mutant analyses uncovers an auxin‑dependent downstream network that drives MMC formation.

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.