Genetius

The study uncovers how arbuscular mycorrhizal (AM) fungi induce lateral root formation in maize by activating ethylene‑responsive transcription factors (ERFs) that regulate pericycle cell division and reshape flavonoid metabolism, lowering inhibitory flavonols. It also shows that the rhizobacterium Massilia collaborates with AM fungi, degrading flavonoids and supplying auxin, thereby creating an integrated ethylene‑flavonoid‑microbe signaling network that can be harnessed to improve nutrient uptake and crop sustainability.

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.

The study demonstrates that very long chain sphingolipids in the outer membrane leaflet interdigitate with inner‑leaflet phosphatidylserine, forming a vertical bridge that organizes PS nanodomains and enables auxin‑induced activation of the Rho‑GTPase ROP6. Disruption of sphingolipid biosynthesis disperses these nanodomains, impairing ROP6 signaling, cytoskeletal dynamics, and directional growth, highlighting interleaflet coupling as a key mechanism linking membrane asymmetry to plant signal transduction.

The study demonstrates that a rapid increase in cytosolic Ca²⁺ is the primary and sufficient signal mediating auxin‑induced root growth inhibition in Arabidopsis. Using live imaging, microfluidics, and optogenetic control of Ca²⁺ influx, the authors show that blocking Ca²⁺ entry prevents growth responses, while light‑triggered Ca²⁺ influx from the apoplast or ER mimics inhibition, indicating that diverse stimuli converge on a Ca²⁺‑dependent mechanism.

The study identifies two maize genes, Discordia3a and Discordia3b, that encode the microtubule‑severing protein KATANIN. Loss‑of‑function allele combinations reduce microtubule severing, impair cell elongation, delay mitotic entry, and disrupt preprophase band and nuclear positioning, leading to dwarfed, misshapen plants.

The study uses an optogenetic ChannelRhodopsin 2 variant (XXM2.0) to generate defined cytosolic Ca²⁺ transients in Arabidopsis root cells, revealing that these Ca²⁺ signatures suppress auxin‑induced membrane depolarization, Ca²⁺ spikes, and auxin‑responsive transcription, leading to reversible inhibition of cell division and elongation. This demonstrates that optogenetically imposed Ca²⁺ signals act as dynamic regulators of auxin sensitivity in roots.

Using CRISPR‑Cas9, researchers knocked down CCD7 or CCD8 in Nicotiana benthamiana to suppress strigolactone synthesis, producing compact plants with a 45%–50% smaller spatial footprint while preserving recombinant protein yields (GFP and rituximab). The mutants showed altered leaf proteome, auxin/cytokinin balance, and metabolic fluxes without affecting overall growth rate, demonstrating suitability for indoor vertical farming biopharma production.

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.