Genetius

The study expressed Arabidopsis thaliana PIN5 (AtPIN5) in tobacco BY-2 cell cultures and observed auxin starvation‑like phenotypes that progressed to programmed cell death (PCD) under strong expression. Metabolite profiling revealed that auxin degradation products generated downstream of AtPIN5 activity largely belong to a re‑emerging auxin decarboxylation pathway, indicating direct induction of PCD by altered auxin homeostasis.

The authors cloned a novel harpin gene (hrpZ2) from Pseudomonas syringae and, using computational analyses, generated a validated three‑dimensional model revealing extensive intrinsic disorder. Infiltration of the recombinant harpin into Nicotiana tabacum and other non‑host angiosperms triggered hypersensitive response symptoms including oxidative burst, callose deposition, localized cell death, and heightened defense enzyme activities, demonstrating its broad-spectrum elicitor potential.

The authors engineered tobacco plants with a phosphate‑deficiency‑responsive promoter driving a fungal self‑sustained bioluminescence system, creating a low‑cost, non‑invasive biosensor that emits light under low Pi conditions. Light intensity correlated with phosphate‑responsive gene expression, tissue phosphorus levels, and decreased upon Pi repletion, and the system was functional when grafted onto tomato and chili pepper, with deep‑learning image analysis enabling quantitative prediction of Pi deficiency.

The study characterizes NtAGL66, an AGAMOUS-like gene in Nicotiana tabacum, as a critical regulator of secretory head development in long glandular trichomes. Overexpression of NtAGL66 enhances secretory structure differentiation, whereas CRISPR-Cas9 knockout impairs gland formation, and transcriptomic and DAP-seq analyses reveal its role in secondary metabolism and broader transcriptional networks.

The study used heterologous expression of the Antirrhinum MYB transcription factor AmMIXTA in Nicotiana tabacum to trigger long‑stalked glandular trichome formation, then performed RNA‑seq to uncover differentially expressed genes and transcriptional cascades. Follow‑up confocal imaging, protein interaction assays, and DAP‑seq validated NtZFP8 as a key regulator of this developmental process, illustrating a workflow for dissecting trichome regulatory networks.

The study engineered tobacco BY-2 cell suspension cultures to produce ketocarotenoid pigments by introducing a marine bacterial β‑carotene ketolase gene and/or overexpressing phytoene synthase and desaturase genes. Single-gene transformants accumulated up to 127 µg g⁻¹ DW astaxanthin and 50 µg g⁻¹ DW canthaxanthin, while co‑expression of all three genes boosted canthaxanthin to 788 µg g⁻¹ DW, demonstrating that undifferentiated plant cells can serve as a sustainable production platform for these high‑value compounds.

The study presents a simple, portable 13CO2 delivery system that integrates with an infrared gas analyzer to enable short‑duration in vivo labeling of plant leaves. Using tobacco leaves, the system generated a defined 13CO2 pulse (~60 ppm) and demonstrated time‑dependent 13C enrichment in specific amino acids via LC‑MS analysis, confirming its efficacy for metabolic flux studies in natural settings.

The study identifies a 2‑bp deletion in the NtFT5 gene of the day‑neutral tobacco cultivar Maryland Mammoth that creates a truncated FT-like protein with reduced floral‑inducing activity, explaining the cultivar’s inability to flower under long‑day conditions and resulting gigantism. Overexpression of the wild‑type NtFT5 restores flowering, while the truncated NtFT5MM remains a weaker inducer, likely due to altered binding affinity for FD proteins.

The study reveals that the tobacco GPI‑anchored protein NtLLG4 acts as a receptor for the pectin methylesterase NtPPME1, directing its unconventional exocytosis via Golgi‑derived secretory vesicles to modulate cell wall stiffness and membrane dynamics at the pollen tube tip. Using cryo‑FIB‑SEM and 3D tomography, the authors identified a distinct vesicle population and mapped trafficking signals that coordinate cell wall rigidity with signaling during fertilization.

The study used transgenic Nicotiana tabacum plants with reduced cytochrome b6/f complex levels to assess how this alteration influences Photosystem I (PSI) protection under fluctuating light. While lower Cyt b6/f content markedly enhanced PSI tolerance to photoinhibition, it concurrently reduced overall electron transport capacity, revealing a trade‑off between photoprotection and photosynthetic performance. These results suggest that modulating Cyt b6/f levels could be a strategy to improve crop resilience in dynamic light environments.