Genetius

The study characterizes the single-copy S-nitrosoglutathione reductase 1 (MpGSNOR1) in the liverwort Marchantia polymorpha, showing that loss-of-function mutants generated via CRISPR/Cas9 exhibit marked morphological defects and compromised SNO homeostasis and immune responses. These findings indicate that GSNOR-mediated regulation of S‑nitrosylation is an ancient mechanism linking development and immunity in early land plants.

The authors created two Nicotiana benthamiana lines with CRISPR-mediated knockouts of two polyphenol oxidase genes, which exhibited slightly accelerated growth and retained normal transient GFP expression. These ppo-deficient plants produced leaf extracts that remained greener with markedly reduced enzymatic browning and protein crosslinking, leading to a nearly fourfold increase in yield and improved purity of a transiently expressed His‑tagged tomato protease. The study demonstrates that PPO depletion can enhance recombinant protein recovery from plant tissue.

The study demonstrates that calcium-dependent protein kinases NbCDPK4 and NbCDPK5 directly phosphorylate the NADPH oxidase NbRBOHB at Ser‑123, enhancing sustained ROS production during effector-triggered immunity in Nicotiana benthamiana. Constitutively active CDPKs also upregulate NbRBOHB transcription, and phosphorylation of Ser‑123 is amplified by Ca2+ influx triggered by an autoactive helper NLR (NRC4). These results define a NbCDPK‑NbRBOHB signaling module that links NLR activation to prolonged ROS bursts in ETI.

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 establishes a transient Agrobacterium-mediated expression platform in Nicotiana benthamiana to produce glycosylated irregular monoterpenes by enhancing DMAPP biosynthesis through co‑expression of DXS, IDI, and HMGR. Engineering of plastidial and cytoplasmic pathways, including a bacterial cyclolavandulyl diphosphate synthase, led to the accumulation of six novel glucoside derivatives, reaching up to 6.6 µmol g⁻¹ fresh weight, the highest reported for plant‑based production.

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 authors present a protocol for the large‑scale isolation of RNA‑binding proteins cross‑linked to RNA, involving in vivo UV‑crosslinking, tissue lysis, fractionation, and organic‑solvent purification of RNA‑protein adducts for downstream proteomics analysis. Although developed with Nicotiana benthamiana leaves, the method can be adapted to other plant species and tissues.

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 visualizes subcellular dynamics following activation of the NRC4 resistosome, showing that NRC4 enrichment at the plasma membrane triggers calcium influx, followed by sequential disruption of mitochondria, plastids, endoplasmic reticulum, and cytoskeleton, culminating in plasma membrane rupture and cell death. These observations define a temporally ordered cascade of organelle and membrane events that execute plant immune cell death.

The study used Nicotiana benthamiana lines expressing fluorescent biosensors for PI4P and PI(4,5)P2 to visualize root colonisation by the pathogen Phytophthora palmivora and the mutualist fungus Funneliformis mosseae. Distinct phosphoinositide patterns distinguished the two interactions, and co‑colonisation induced recruitment of PI4P to pathogen haustoria, correlating with increased resistance, indicating dynamic remodeling of host membrane identity.