Genetius

The study reconstitutes Papaver rhoeas self‑incompatibility (SI) in Arabidopsis thaliana by expressing the pollen S‑determinant PrpS, revealing that SI triggers a rapid Ca2+‑dependent signaling cascade that leads to mitochondrial H2O2 production, metabolic collapse, and programmed cell death. Using a genetically encoded H2O2 sensor and metabolic assays, the authors show that early mitochondrial disruption, driven by altered Ca2+, cytosolic pH, and distinct ROS sources, is central to the SI response.

The study compared two plasma‑activated water (PAW) solutions with different H₂O₂ levels, produced by a radio‑frequency glow discharge, on Arabidopsis thaliana growth and stress responses. PAW lacking detectable H₂O₂ promoted seedling growth and induced nitrogen‑assimilation genes, while H₂O₂‑containing PAW did not affect growth but enhanced root performance under heat stress; mature plants fertilized with H₂O₂‑free PAW performed comparably to nitrate controls. These results indicate PAW can replace NO₃⁻ fertilizers provided H₂O₂ levels are carefully managed.

The study demonstrates that constitutively active MLO (faNTA) can rescue the fer-4 root‑hair bursting and polarity defects, restoring tip‑focused cytosolic Ca2+ oscillations and ROS accumulation, highlighting a FERONIA‑MLO signaling module that governs Ca2+ influx and ROS production during root‑hair tip growth. Genetic analysis of mlo15-4 further confirms MLO15 as a key regulator of these Ca2+ and ROS dynamics. The findings suggest MLO proteins act downstream of FER to coordinate calcium and ROS signals essential for root‑hair integrity.

The study reveals that reactive oxygen species (ROS) have distinct temporal roles in Arabidopsis thaliana stigma papillae development, with superoxide promoting early growth and hydrogen peroxide marking mature, pollen‑receptive papillae. Pharmacological reduction of superoxide or transgenic over‑expression of superoxide dismutase under an early stigma promoter impairs papillae growth, highlighting ROS homeostasis as essential for proper papillae differentiation and successful pollination.

Loss‑of‑function mutations in the drought‑induced genes GASA3 and AFP1 confer enhanced drought tolerance in Arabidopsis thaliana, primarily through smaller stomatal apertures and increased ABA accumulation via hydrolysis of ABA‑GE. Constitutive overexpression of these genes heightens drought sensitivity, indicating that the AFP1/GASA3 module negatively regulates stomatal closure and ABA signaling.

The study identifies HISTONE DEACETYLASE COMPLEX 1 (HDC1) as a positive regulator of sepal size during maturation in Arabidopsis thaliana, showing that hdc1 mutants exhibit prolonged elongation due to delayed maturation. Integrated transcriptomic and proteomic analyses, together with genetic and chemical experiments, reveal that HDC1 promotes ethylene production, which in turn triggers ROS accumulation to terminate sepal growth. These findings elucidate a coordinated ethylene‑ROS signaling mechanism controlling organ size during plant development.

The study demonstrates that dihydroxy B‑ring flavonoids modulate the amplitude of the core circadian clock gene reporter TOC1:LUC in Arabidopsis by affecting cellular H2O2 levels, rather than auxin transport. Reducing reactive oxygen species restored normal TOC1:LUC amplitude in flavonoid‑deficient seedlings, and altered chloroplast Ca2+ levels suggest a retrograde signaling component.

The study surveyed vegetative water use and life‑history traits across Arabidopsis thaliana ecotypes in both controlled and outdoor environments to assess how climatic history shapes water‑use strategies. Trait‑climate correlations and genome‑wide association analyses uncovered that ecotypes from warmer regions exhibit higher water use, and identified MYB59 as a key gene whose temperature‑linked alleles affect water consumption, a finding validated using myb59 mutants. These results indicate that temperature‑driven adaptive differentiation partly explains intraspecific water‑use variation.

The study identifies the scaffolding protein RACK1A as a cytoplasmic interaction partner of the antioxidant enzyme FSD1, revealing that RACK1A recruits FSD1 to cycloheximide-sensitive condensates that colocalize with stress granules during salt stress. Functional analyses show that this RACK1A‑FSD1 module modulates ROS levels, influences root hair tip growth, and determines salt‑stress resilience in Arabidopsis.

The study reveals that hydrogen sulfide (H₂S) and the cysteine desulfhydrase DES1 are essential for stomatal immunity, mediating flg22‑ and bacterial‑induced stomatal closure and influencing reactive oxygen species (ROS) dynamics. Loss‑of‑function des1 mutants show altered susceptibility to Pseudomonas syringae and reduced apoplastic and cytosolic H₂O₂ accumulation, while H₂S can induce ROS production independently of RBOHD.