Plant Cell Reports最新文献

Microplastic pollution has emerged as a critical environmental concern, particularly in agricultural soils, where various MP types, including polyethylene, polystyrene and polyvinyl chloride accumulate due to plastic mulch degradation, irrigation, and biosolid application. This review synthesizes current knowledge on the impacts of MPs on soil integrity and function, highlighting the degradation of soil structure, disruption of nutrient cycles and shifts in microbial community composition and enzymatic activity. Furthermore, MPs can be taken up by plants, with submicrometer sized particles infiltrating root tissues, triggering phytotoxic effects such as oxidative stress, impaired growth, and reduced photosynthesis. In response plants deploy tolerance mechanisms involving antioxidant defense and altered nutrient metabolism to mitigate MP-induced stress. Advanced omics technologies, including transcriptomics, metabolomics, and proteomics provide valuable insights into the molecular responses of plants to MP exposure, uncovering stress responsive genes, metabolite shifts and protein alterations linked to MP toxicity. This review synthesizes current knowledge on MP contamination in agricultural soil, its impact on soil health and plant physiology, and the application of multiomics approaches to elucidate MP-induced toxicity, paving the way for sustainable strategies to mitigate MP pollution in agroecosystems.

Key message: Using CRISPR/Cas12a, we engineered novel soybean germplasms by knocking out GmFAD2 (GmFAD2-1A, GmFAD2-1B) and GmFAD3 (GmFAD3A, GmFAD3B) genes, yielding elevated oleic or linoleic acid content. Soybean oil contains high levels of polyunsaturated fatty acids (PUFAs), which are known to reduce cholesterol levels and help prevent hypertension, thereby contributing significantly to human health. However, the chemical instability of PUFAs makes them susceptible to oxidation, a process that generates harmful trans-fatty acids. To address this issue, precise modulation of fatty acid composition in soybeans becomes critically important for health applications. In this study, we employed CRISPR/Cas12a gene editing technology to selectively knock out the GmFAD2 (GmFAD2-1A, GmFAD2-1B) and GmFAD3 (GmFAD3A, GmFAD3B) genes in soybean. This approach successfully created novel soybean germplasms with distinct fatty acid profiles: one with elevated oleic acid content and another with increased linoleic acid levels. These engineered variants provide valuable options for utilizing soybean oil with optimized fatty acid compositions tailored for specific health and nutritional purposes.

Key message: The RUBY reporter enabled the evaluation of different transgene expression constructs in lettuce, revealing that the lettuce ubiquitin promoter and terminator had strong expression that was stable over multiple generations. Nearly four decades after the first transgenic lettuce was reported, constructs for stable transgene expression remain limited. Notably, the 35S promoter from the Cauliflower Mosaic Virus (35S), which drives strong expression of transgenes in several plant species, has often shown silencing and instability in lettuce. Other promoter/terminator combinations that are commonly used in plant expression vectors have not been extensively studied in lettuce. In this study, we evaluated three different expression constructs in two different horticultural types of lettuce using the non-invasive RUBY reporter, which allowed for the monitoring of transgene expression throughout the process of regeneration during tissue culture, throughout development of the primary transgenics, and in two subsequent sexual generations. The LsUBI promoter/terminator combination resulted in strong, uniform expression throughout regeneration, during growth of the primary transgenics, and in both subsequent generations. The AtUBI promoter/tRBCS combination showed slightly lower levels of expression and intermediate levels of silencing, while the 35S promoter/tHSP combination showed both initial strong expression and frequent silencing. Therefore, our data show that the LsUBI promoter/terminator combination provides strong, uniform expression that is unlikely to result in silencing and that the AtUBI promoter/tRBCS combination is an additional option for stable expression of transgenes in lettuce, especially if an intermediate expression level is desired.

Key message: Novel endophytic bacterial consortium promotes the growth of Solanum lycopersicum surviving salt stress by differentially regulating the primary and secondary metabolic pathways. Crop yield is being impacted by global warming, which threatens food security. Salinization of soil or irrigation water is becoming increasingly prevalent in most agricultural terrain, especially around the coast. In India, it is estimated that approximately 10% of additional area is getting salinized, and around 50% of the arable land would be salt-affected by the year 2050. Finding innovative techniques that enable farmers to sustain production in an increasingly saline environment is crucial given the world's population expansion and the depletion of natural resources used in agriculture. Biostimulants are naturally occurring compounds or microorganisms that are used to promote plant functions, such as nutrient absorption, nutrient utilisation efficiency, abiotic stress tolerance, and the overall quality of the resulting agricultural products. In the present work, we evaluated the agronomic effectiveness of a novel formulated biostimulant consisting of four strains of endophytic bacteria isolated from the roots of mangrove plants of Sundarbans in a crop of great interest (Tomato) under controlled conditions and salt stress. Our research has shown that our product had a positive effect on the biochemical parameters in tomato plants under salt stress. The application of our biostimulant also increased osmolyte production and maintained Na⁺/K⁺ homeostasis under salt conditions. Similarly, when exposed to salinity, the biostimulant increased the concentration of signature molecules, including primary metabolites, phenolic compounds, polyamines, and phytohormones inside the plant cell. This study enriched our body of knowledge by providing novel perspectives on the mechanism of salt resistance that endophytic microbes provide through symbiosis.

Key message: NtRPP13, a CNL-type gene suppressed by Ralstonia solanacearum, mediates a positive regulation of hypersensitive response and phytohormone-related defense genes for bacterial wilt resistance in tobacco. Bacterial wilt, caused by Ralstonia solanacearum, is a devastating soil-borne disease that infects hundreds of plant species worldwide. To date, while effective control strategies for this pathogen remain limited, exploring resistant genes is particularly important in disease-resistant breeding. Nucleotide-binding site-leucine-rich repeat (NBS-LRR) proteins are key participants in effector-triggered immunity in plants. This study identified a novel NBS-LRR resistance gene, NtRPP13, in tobacco, which exhibited downregulation in roots of a susceptible tobacco cultivar upon R. solanacearum infection. The NtRPP13 protein contained a typical coiled-coil (CC) domain at its N-terminus and was classified into the CC-NBS-LRR category. Subcellular localization analysis revealed that NtRPP13 localizes to the plasma membrane. Additionally, exposure to phytohormones-including abscisic acid, auxin and gibberellic acid, and abiotic stressors such as drought and cold altered NtRPP13 expression. This could be attribute to the corresponding cis-acting elements in the NtRPP13 promoter. Transient overexpression of NtRPP13 triggered a hypersensitive response (HR) in Nicotiana benthamiana, while stable overexpression in transgenic tobacco plants significantly enhanced resistance to R. solanacearum, with varying resistance levels observed between different transgenic lines. Moreover, following inoculation with R. solanacearum, the transgenic plants exhibited marked upregulation of some key defense-related marker genes associated with the HR, salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways, along with significantly elevated levels of JA and SA, compared to wild-type controls. These findings suggest that NtRPP13 contributes to tobacco defense against R. solanacearum by mediating crosstalk between multiple signaling pathways.

Key message: A novel male sterility line Nan A forms normal microspore tetrads, but defective pollen development. Dysregulated fertility/stress-related genes in anthers cause cotton male sterility. Cotton exhibits significant heterosis, characterization of genic male-sterility (GMS) genes is crucial for unraveling molecular mechanisms controlling anther and pollen development, and enables the development of biotechnology-based male-sterility systems for commercial hybrid seed production. Here, we report a combined cytological and transcription analyses of the anther of a single-gene recessive GMS line Nan A and its near-isogenic male fertile line Nan B, and further verified the functions of two male sterility-related genes. Nan A developed shorter stamen filaments, produced sterile pollens characterized by shriveled starch grains inside, delayed nexin deposition, without spines on exine surface, and failure in dehiscence. A number of anther-preferentially expressed genes were unexpectedly up-regulated in Nan A, whereas loss-of-function mutants of their homologous genes in other plant species exhibit male sterility. By contrast, a number of stress-related transcription activation protein genes are down-regulated in Nan A. Either silencing the anther specifically expressed GhCYP450 that down-regulated or overexpressing GhPHD-D that up-regulated in Nan A can convert wild-type into male sterility. Our results indicate that timely expression of anther and/or pollen developmental genes are pivotal for male fertility.

Key message: Exogenous GA₃ lowers the C:N ratio, depleting starch/sucrose and suppressing flowering, while untreated control plants maintain normal C:N, ample carbohydrates, and higher floral-promoter expression, supporting floral initiation. This study elucidates the regulatory role of gibberellin-3 (GA₃) in nitrogen (N) and carbon (C) metabolism and its association with bud dormancy in pitaya (Hylocereus polyrhizus). Exogenous GA₃ application completely inhibited floral bud development, maintaining dormancy, whereas untreated control plants progressed to active flowering. GA₃-treated plants exhibited elevated nitrogen content but reduced carbon allocation, alongside significant declines in sucrose, glucose, fructose, total sugars, and starch compared with controls. Transcriptomic profiling identified numerous differentially expressed genes (DEGs) linked to N/C metabolism, starch/sucrose pathways, and aligning with observed trends in nitrogen, carbon and sugar level changes. Key flowering-promoting transcription factors (TFs) (e.g., PHYB, CRY, VIN3-like, TCP) and floral integrators (e.g., FY, FLK, AGL, FTIP) were downregulated under GA₃, while N-assimilation genes and dormancy-associated TFs (e.g., CDF) and floral inhibitors (e.g., SOC1) were upregulated. These results demonstrate that GA₃ disrupts the metabolic transition from N-to-C utilization necessary for floral activation, likely through coordinated suppression of flowering-promoting networks and enhancement of nutrient metabolism pathways. Our findings provide mechanistic insights into GA₃-mediated dormancy and highlight its potential application in synchronizing pitaya cultivation cycles.

Key message: BjZIP1 is a plasma membrane-localized protein. Overexpression of BjZIP1 in yeast, Arabidopsis thaliana, and Brassica juncea hairy roots confirmed its role in promoting Cd/Zn uptake. Heavy metal contamination in agricultural soils significantly threatens global food security. While Brassica juncea is recognized as a promising hyperaccumulator for phytoremediation, the specific transporters mediating its metal uptake remain largely unexplored. Here, we identify BjZIP1, a plasma membrane-localized protein that functions as a transporter for cadmium (Cd) and zinc (Zn) uptake in B. juncea. Heterologous expression of BjZIP1 in Cd-sensitive yeast mutant (Δyap1) increased intracellular accumulation of Cd and Zn by 17.8% and 25.0%, respectively, and consequently enhanced metal sensitivity. In Arabidopsis thaliana, BjZIP1 overexpression lines accumulated 31.1-58.3% more Cd and 1.68-2.48-fold higher Zn in roots under metal stress, which was accompanied by a growth inhibition phenotype. Crucially, BjZIP1-overexpressing B. juncea hairy roots accumulated 1.05-1.30-fold more Cd and 1.42-1.92-fold more Zn, alongside a concomitant exacerbation of cellular damage under Cd exposure. Collectively, our results establish BjZIP1 as a plasma membrane transporter responsible for Cd and Zn uptake in B. juncea, thereby providing a promising molecular target for genetic enhancement of phytoremediation efficiency.

Key message: JrWOX5 promotes adventitious root formation and modulates plant architecture by interacting with key developmental regulators, providing novel insights into WOX-mediated organogenesis in woody plants. WUSCHEL-related homeobox (WOX) transcription factors, a plant-specific gene family, play essential roles in regulating plant development, including stem cell maintenance and organogenesis. Among the WOX genes identified in Juglans regia, JrWOX5 exhibited significantly elevated expression during AR formation, suggesting a potential regulatory role in this process. To investigate its function, we employed a combination of bioinformatics analysis, subcellular localization, heterologous overexpression, yeast two-hybrid (Y2H) assays, and bimolecular fluorescence complementation (BiFC). The JrWOX5 protein was localized to the nucleus. Ectopic expression of JrWOX5 in transgenic poplar markedly promoted AR formation and altered plant architecture, characterized by increased lateral branching and reduced plant height. To elucidate the molecular mechanism, protein-protein interaction (PPI) network analysis was conducted, and key candidate interactors were experimentally validated. JrWOX5 was found to interact with JrLBD16, a LOB domain-containing protein; JrLHW, a transcription factor; and JrCNR8, a regulator of cell proliferation. These findings indicate that JrWOX5 interacts with developmental regulators, which may jointly affect organogenesis and plant architectural patterning. This study aims to provide a new insight into WOX-associated organogenesis in woody plants.