Search Results (211)

Intensifying drought stress under global climate change poses a significant threat to woody plants, highlighting the critical need to identify key genes conferring drought tolerance. Here, we characterized PsnSAUR6, a Small Auxin Upregulated RNA (SAUR) family gene from poplar (Populus simonii × P. nigra) that is responsive to drought and abscisic acid (ABA). Overexpression of PsnSAUR6 in transgenic tobacco conferred superior drought tolerance, evidenced by increased biomass, enhanced root elongation, improved stomatal regulation, and favorable physiological responses, including higher proline content and peroxidase (POD) activity but lower malondialdehyde (MDA). Transcriptome analysis revealed that under water deficit, PsnSAUR6 suppressed the ABA negative regulator PP2C37 while upregulating key antioxidant defense-related transcription factors (ERF020, NAC83, MYB2) and the potassium transporter HAK5. Collectively, these findings establish PsnSAUR6 as a positive regulator in ABA-mediated drought adaptation, presenting it as a promising genetic target for enhancing the climate resilience of woody plants. Full article

Background:Pinellia ternata is a major medicinal herb widely utilized in traditional medicine, but is sensitive to high temperature, which often triggers a severe “sprout tumble” phenomenon. Methods: To elucidate the molecular mechanisms of heat tolerance in P. ternata, we screened two contrasting germplasms: the heat-tolerant JBX1 and the heat-sensitive XBX4. In the present study, a combined analysis of physiology, transcriptome, and metabolome was performed on JBX1 and XBX4 under heat stress at 40 °C. Results: JBX1 exhibited significantly greater leaf thickness, higher basal chlorophyll content, more stable antioxidant enzyme activities, and lower oxidative damage than XBX4 under heat stress. Transcriptomically, JBX1 maintained elevated basal expression of genes encoding key enzymes in carbon fixation, amino acid metabolism, and phenylpropanoid biosynthesis, as well as those encoding heat shock transcription factors (HSFs), heat shock proteins (HSPs), and the thermosensor Thermo-With ABA-Response 1 (TWA1). Metabolomically, JBX1 accumulated higher levels of key primary metabolites, antioxidants, and protective phenylpropanoids under both control and heat conditions. Notably, a “polarity reversal” emerged in nitrogen metabolism, where core amino acids accumulated in JBX1 but were depleted in XBX4. Integrated analysis revealed a more coordinated gene–metabolite network in JBX1 involving the phenylpropanoid, ATP-binding cassette (ABC) transporter, and glutathione pathways. Conclusions: Our findings demonstrate that JBX1 possessed stronger basal thermotolerance, which is derived from coordinated establishment of higher constitutive metabolic reserves and efficient dynamic metabolic reprogramming. This study provides insights into the molecular mechanisms of heat stress in P. ternata. Full article

Seed germination is a critical initial stage of the plant life cycle, regulated by signaling pathways such as phytohormones and reactive oxygen species (ROS). However, the low germination rate of immature grains is a key bottleneck limiting wheat speed breeding. This study used immature grains of the winter wheat cultivar Kenong 199 (KN199) collected 18 days post anthesis to establish an efficient germination protocol. By screening individual and combined treatments of hydrogen peroxide (H₂O₂, 1%), gibberellin (GA₃, 20 μM), and varying concentrations of abscisic acid (ABA) synthesis inhibitor sodium tungstate (Na₂WO₄), alongside transcriptome analysis, we identified the optimal reagent combination and gained preliminary insight into its molecular basis. The triple reagent combination of 0.5 mM Na₂WO₄ + 20 μM GA₃ + 1% H₂O₂ exhibited the highest germination rate of 80%, approximately sevenfold higher than single reagent treatments, with germination rate peaking after 4 days. Transcriptome profiling revealed that this combination modulated the expression of key genes related to dormancy release and germination, including upregulation of GA biosynthesis gene GA3ox2 and ABA catabolism gene TaCYP707A2, and downregulation of ABA biosynthesis and signaling genes (ABI5, TaNCED1, etc.). Additionally, genes associated with energy metabolism and transport pathways were enhanced. This optimized reagent combination significantly improves immature grain germination, shortens the breeding cycle, and provides a practical tool for achieving “five generations per year” speed breeding in winter wheat. Our findings contribute to seed biology by offering a chemical strategy to overcome dormancy in immature cereal grains. Full article

Background: Tartary buckwheat (Fagopyrum tataricum) serves as an excellent model for studying plant water adaptation mechanisms due to its exceptional drought tolerance. While aquaporins (AQPs) mediate the transmembrane transport of water and solutes in plants, their fine-tuned regulatory networks underlying stress resilience in Tartary buckwheat remain largely elusive. Methods: Here, we combined bioinformatics and transcriptomics to systematically identify 30 highly conserved FtAQP genes at the genome-wide level. Results: Cross-validated by qRT-PCR, our analysis revealed their distinct expression patterns across different organs. Based on our transcriptomic data, we hypothesize that FtAQP family members potentially participate in a coordinated whole-plant water management network through differential spatiotemporal expression. Specifically, the robust transcription of FtAQP8, FtAQP12, and FtAQP28 in roots is associated with the initial water uptake process. As water undergoes long-distance transport, the synergistic upregulation of FtAQP13, FtAQP17, FtAQP20, and FtAQP29 in the stem suggests a potential role in facilitating critical lateral water flow. Furthermore, during reproductive development, FtAQP27 exhibits extreme tissue specificity in floral organs, implying its possible involvement in maintaining local osmotic homeostasis. Furthermore, the promoter regions of FtAQPs are highly enriched with cis-acting elements responsive to light, abscisic acid (ABA), and cold stress, suggesting they are intimately regulated by a coupling of endogenous phytohormones and environmental cues. Conclusions: Ultimately, this study provides valuable insights into the potential molecular basis of multidimensional water regulation in Tartary buckwheat, and identifies candidate genetic targets for improving water use efficiency in dryland agriculture through the precise manipulation of aquaporins. Collectively, while these observational findings provide valuable predictive models, future in vivo experimental validations are required to confirm their exact biological functions. Full article

Abscisic acid (ABA) is a major phytohormone regulating plant growth and stress responses. Subclass III SnRK2 kinases and clade A type 2C protein phosphatases (PP2Cs) are core components of ABA signaling. Despite advances from phosphoproteomics, major gaps remain, particularly in mapping PP2C dephosphorylation targets and SnRK2-dependent phosphorylation dynamics under non-stress conditions. Here, we performed large-scale LC–MS/MS phosphoproteomic analyses using the subclass III SnRK2 triple mutant srk2dei and the constitutively active PP2C mutant abi1–1C, with and without ABA treatment in Arabidopsis thaliana. We identified 2757 and 2886 differentially regulated phosphopeptides in srk2dei and abi1–1C, respectively. Beyond known ABA signaling components, these datasets revealed numerous previously uncharacterized candidate proteins involved in metabolism, membrane transport, transcription, and cytoskeletal regulation. Integrative analysis uncovered a core set of candidate proteins oppositely regulated by SnRK2-mediated phosphorylation and ABI1-mediated dephosphorylation, defining a coordinated hierarchical network. These results indicate that the SnRK2–PP2C module functions not only in stress-induced ABA responses but also as a central regulator of phosphorylation homeostasis under basal conditions. This study provides a systematic framework for the global SnRK2–PP2C phosphorylation network and reframes ABA signaling as a dynamic homeostatic system. Full article

Toxic aluminum (Al) and iron (Fe) alter the hormonal balance of plants, leading to metabolic disorders and growth inhibition. Plants adapt to abiotic stress by optimizing phytohormone biosynthesis. However, the impact of toxic Al and Fe on plant hormonal status is poorly understood. Pea cultivar Sparkle and its mutant E107 (brz), accumulating Al and Fe due to disfunction of metal transporter gene OPT3, were cultivated in hydroponics supplemented or not with 80 µM of AlCl₃ or 300 µM of FeCl₃. Root and shoot biomass of E107 decreased due to Al or Fe treatments approximately by 30%, whereas growth of Sparkle was not affected. The Al and Fe content in the roots and shoots of the metal-treated mutant was circa twice that of Sparkle. Treatment with Al and Fe reduced the content of nutrients (Ca, K, Mg, S) in roots and/or shoots in both genotypes. Compared with Sparkle, untreated E107 possessed lower IAA and higher ethylene and tZR contents in roots but lower GA3, DHZ and tZ content in shoots. Mutant E107 had: lower GA3 and ethylene but higher DHZ, tZ and tZR contents in Al-treated roots; higher ABA, SA, IAA, GA3, DHZ, and tZ contents in Al-treated shoots; lower ABA and SA but higher JA, GA3, DHZ and ethylene contents in Fe-treated roots; higher ABA, SA, IAA, GA3, DHZ, and tZ contents in Al-treated shoots; higher ABA, JA, and GA3 but lower ethylene and tZR contents in Fe-treated shoots. Metal toxicity mainly reduced the content of phytohormones in roots and increased it in shoots. Hormonal disturbances were more significant in E107 than in Sparkle, and the effect of Al was stronger than Fe. Thus, toxic Al and Fe lead to complex, metal- and organ-specific changes in the hormonal status of E107. Hormonal changes might be associated with both defense reactions and the toxic effects of metals on plants. Full article

Drought significantly disrupts rice productivity under increasing climate volatility. Identifying robust molecular determinants for resilience remains a critical priority for crop improvement. Following the PRISMA guidelines, we performed a large-scale, dual-platform meta-analysis of RNA-Seq and microarray datasets to elucidate the robust transcriptomic landscape of Oryza sativa underwater deficit. Tissue-specific regulatory pathways were identified using STRING, g:Profiler, and PANTHER. Our analysis resolved distinct functional divergence, where shoots prioritize photosynthetic adjustment while roots emphasize transcriptional and chromatin reprogramming. Beyond validating core ABA signaling, we uncover a novel metabolic pivot: the activation of glyoxylate and dicarboxylate metabolism to mitigate drought-induced carbon starvation. We further identify specialized transport systems for ions and electrons across organelle membranes, alongside cellular reorganization driven by autophagy and actin-dependent cytoskeleton remodeling. These findings highlight a sophisticated network of survival strategies governing energy conservation and structural adaptation. By synthesizing heterogeneous transcriptomics, this study reveals robust pathways that are overlooked in single-platform investigations. This work provides a prioritized roadmap for utilizing functional validation and precision breeding to accelerate the development of climate-resilient rice cultivars. Full article

Winter oilseed rape achieves frost tolerance through cold acclimation, which develops naturally in autumn in response to low but non-freezing temperatures. However, ongoing climate change has led to an increasing instability in winter temperatures, with more frequent warm breaks. Such temperature fluctuations can induce deacclimation, resulting in a partial or complete loss of frost tolerance and reduced winter survival. Water management is a critical determinant of plant survival under such conditions, yet its regulation during the acclimation–deacclimation transition remains incompletely understood. This study investigated tissue-specific changes in key components of water management in winter oilseed rape subjected to non-acclimated, cold-acclimated, and deacclimated conditions. Proline accumulation, abscisic acid content in plant tissue and cell sap, and the expression of aquaporin genes BnPIP2 and BnTIP1 were analyzed in leaves, root necks, and roots. Cold acclimation induced a strong accumulation of proline and ABA, accompanied by marked downregulation of aquaporin expression in all tested tissue. Deacclimation resulted in partial reverse of proline and ABA. Aquaporins expression demonstrated tissue-specific recovery, showing increases in all tissue compared to cold-acclimated plants. Our findings demonstrate that coordinated actions of integrated water transport, osmotic adjustment, and hormonal signaling in regulating water balance and frost tolerance during winter temperature fluctuations. Full article

As both an energy source and a signaling cue, light quality regulates graft healing by modulating endogenous phytohormone homeostasis, callus formation, and vascular reconnection. To elucidate the regulatory roles of red/blue (R/B) light ratios and green light supplementation on healing and seedling quality of grafted tomato (Solanum lycopersicum L.), a controlled-environment experiment was conducted in a plant factory using ‘Zhongza 105’ as the scion and ‘Zhezhen No. 1’ as the rootstock. LED lighting treatments were established with different R/B ratios (1.0, 2.5, 4.0, 5.5 and 7.0) with or without supplemental green light. The results show that moderate R/B ratios (4.0–5.5) significantly increased scion elongation, the stem diameter of both scion and rootstock, the mechanical strength of the graft union, and sap flow, while also enhancing leaf chlorophyll content, photosynthetic rate, and root activity. Under optimal R/B conditions, indole-3-acetic acid (IAA) and gibberellin (GA) levels were elevated, whereas abscisic acid (ABA) was reduced, favoring callus proliferation and vascular reconnection. Green light supplementation under moderate R/B further promoted stem thickening, leaf area expansion, water transport across the graft union, and total biomass accumulation. Overall, an R/B ratio of 4.0–5.5 combined with appropriate green light supplementation optimized the morphology, structure, and physiological performance of grafted tomato seedlings during the healing stage. The results aim to provide a scientific basis for optimizing light environments in a controlled environment, thus enhancing the stability and quality of grafted tomato seedlings. Full article

In the process of maize production, extreme meteorological conditions such as drought and high temperature are often the main environmental stress factors affecting pollination efficiency. Previous studies have shown that, under adversity, the germination rate of pollen grains on the filaments of female spikes directly affects the success rate of reproduction and ultimately determines the grain yield. This study focuses on a cysteine protease named ZmPCP. The expression of this protease in maize pollen is significantly higher than in other tissues, and its specific function has not been clearly defined. Its localization in the cell membrane or apoplast was further confirmed by transient transfection experiments and plasmolysis. The interaction between ZmPCP and ZmSNAP33 was verified by yeast two-hybrid technology and a GST pull-down experiment, indicating that ZmPCP may affect pollen germination and stress resistance by regulating vesicle transport. Secondly, by analyzing the pollen germination rate of maize inbred lines B104, ZmPCP-KO and ZmPCP-OE transgenic maize plants, we found that ZmPCP overexpression could significantly enhance pollen viability and pollen tube growth under drought stress. After 1 h of short-term drying treatment, the pollen germination rate of the ZmPCP-OE line was maintained at 44%, which was significantly higher than that of the other lines. In addition, the observation of pollen tube growth showed that ZmPCP overexpression could promote the extension of pollen tubes in the filament. Moreover, a transcriptome sequencing analysis revealed the regulatory effects of ZmPCP on pollen in multiple biological processes, including stress response, carbohydrate metabolism, growth and development, cell wall material metabolism, signal transduction, etc. The involved pathways of these differential genes indicate that ZmPCP enhances pollen drought tolerance and promotes pollen tube growth through a “metabolism signal structure”. In the germination experiment on the seventh day, the germination rate of ZmPCP-OE maize seeds was the lowest, indicating that its overexpression inhibited seed germination. At the same time, ZmPCP-overexpressing Arabidopsis showed a significant advantage in taproot growth under high-concentration ABA stress. ZmPCP provides an important theoretical basis for regulating the pollination process and improving the pollination efficiency of maize varieties through interaction with ZmSNAP33. Full article

Cadmium (Cd) is a highly toxic heavy metal that severely impairs plant growth and poses ecological and health risks. Chrysanthemum indicum (L.), a dominant species in Cd-contaminated regions, represents a valuable germplasm for phytoremediation. In this study, we cloned and characterized CiWRKY50, a WRKY transcription factor containing a conserved WRKY domain and C2H2-type zinc finger. CiWRKY50 was localized to the nucleus but lacked intrinsic transcriptional activation activity. Overexpression of CiWRKY50 in Arabidopsis thaliana and C. indicum significantly enhanced Cd tolerance, as shown by reduced root Cd accumulation, improved transport efficiency, lower ROS and MDA levels, and increased chlorophyll, proline, and soluble protein contents. Antioxidant enzyme activities and Cd-chelating compounds (GSH, NPT, PCs) were also upregulated. Furthermore, combined Cd and ABA treatments promoted Cd sequestration in roots and activated ABA-responsive genes (CiABF1, CiABF2, CiABF4), alleviating shoot toxicity. These findings indicate that CiWRKY50 enhances Cd tolerance in association with enhanced ABA-mediated signaling and redox homeostasis, providing new insights for breeding Cd-resistant plants and improving phytoremediation strategies. Full article

The circadian clock genes in tomato are key regulators of cold stress adaptation. However, the low-temperature regulatory mechanism of the circadian clock gene SlPCL1 remains unclear. In this study, we evaluated the role of SlPCL1 in cold tolerance through low-temperature treatment of transgenic plants. Downstream target genes were identified using RNA-seq, RT-qPCR, yeast-one-hybrid (Y1H), dual-luciferase assays, and electrophoretic mobility shift assay (EMSA), while interacting proteins were characterized using yeast-two-hybrid (Y2H), luciferase complementation imaging (LCI), and pull-down assays, thereby elucidating the molecular mechanism underlying SlPCL1-mediated low-temperature regulation. We identified SlPCL1 as a nuclear-localized circadian clock gene with transcriptional repressor activity. Overexpression of SlPCL1 resulted in a cold-sensitive phenotype, whereas virus-induced gene silencing (VIGS)-mediated silencing of SlPCL1 enhanced cold tolerance. SlNPF4.6 functions as an abscisic acid (ABA) transporter involved in ABA transport. RNA-seq and RT-qPCR identified the ABA transporter SlNPF4.6 as a downstream target. Functional assays confirmed that SlPCL1 binds to the MYB element in the SlNPF4.6 promoter to repress its expression. Meanwhile, VIGS-mediated silencing of SlNPF4.6 decreased cold tolerance. Furthermore, the expression levels of the ABA receptor SlPYLs in the silenced lines were significantly reduced, confirming the decrease in intracellular ABA content. SlSUMO1, a ubiquitin-like protein, can influence gene transcription through noncovalent interactions. In addition, SlSUMO1 was found to interact with the SlPCL1 protein, attenuating SlPCL1 transcriptional repression activity. Together, these findings establish an SlSUMO1-mediated fine control mechanism of the SlPCL1-SlNPF4.6 regulatory module. This integration of circadian clock regulation uncovers new molecular mechanisms of cold tolerance and supports the development of cold-resistant breeding materials. Full article

Drought severely limits plant productivity, and understanding its regulatory mechanisms remains essential. Here, we characterize Lipid Transport Superfamily-Polyketide cyclase/dehydrase (LTS-PYL), a PYR/PYL/RCAR-domain gene, using Arabidopsis overexpression and CRISPR-Cas9 genome-edited lines to elucidate its role in drought adaptation. LTS-PYL overexpression enhanced early seedling growth, increasing root length (RL) by 40% and 31%, whereas genome-edited lines exhibited severe defects, including 42%, 28% reductions in fresh weight and 63%, 50% decreases in root length relative to WT-T. Under drought stress, overexpression lines displayed strong growth and reproductive resilience, with shoot length (SL) increased by up to 80%, silique length (Sil L) by 61%, and seed number doubled compared with WT-T. In contrast, genome-edited lines showed marked reductions in these traits, confirming their drought sensitivity. LTS-PYL overexpression strongly suppressed oxidative stress, reducing H₂O₂ by 74% and 68% and O₂⁻· by 39% and 38%, while increasing relative water content (RWC) by 42% and 39%. Genome-edited lines exhibited elevated (H₂O₂, O₂⁻·) and up to 33% lower RWC. Antioxidant capacity was also strengthened in overexpression plants, with catalase (CAT) and peroxidase (POD) activities increasing by 138%, 168% and 62%, 148%, and malondialdehyde (MDA) and electrolyte leakage (EL) reduced by 23%, 37%, relative to WT-T. Conversely, genome-edited lines showed weakened antioxidant defenses and higher membrane damage. Transcriptionally, overexpression activated drought-responsive genes, elevating LTS-PYL (604%, 472%), DREB2A (227%, 200%), and ABA levels (48%, 34%), whereas genome-edited lines showed strongly reduced expression and ABA decreases of 66%, 62%. Additionally, LTS-PYL enhanced osmotic adjustment, increasing proline (58%, 53%), sugars (37%, 46%), and sucrose (111%, 100%), while limiting chlorophyll (Chl) loss to 9%, 20%. Genome-edited lines exhibited reduced osmolytes and severe chlorophyll decline. Overall, LTS-PYL acts as a strong positive regulator of drought tolerance, integrating ABA signaling, osmotic adjustment, ROS detoxification, and transcriptional activation. Full article

Vacuolar H⁺-ATPases play crucial roles in plant ion homeostasis and stress adaptation, yet the functional characterization of their subunit genes in purslane remains limited. In this study, PoVHA-a3, encoding a tonoplast-localized V-ATPase a3 subunit, was identified as a key salt-responsive gene through transcriptomic analysis. Integrated bioinformatic analysis and molecular docking simulations predicted specific binding of NAC3, MYB1, and bHLH62 to the PoVHA-a3 promoter, suggesting their synergistic role in regulating PoVHA-a3 expression. Under salt stress, PoVHA-a3 transgenic Arabidopsis lines exhibited elevated endogenous abscisic acid levels and upregulation of signaling genes (AtNCED3, AtRD29A, AtCOR15A), while the brassinosteroid signaling pathway was suppressed, as indicated by the reduced expression of AtBZR1 and AtEXPA8. Meanwhile, the transgenic lines demonstrated enhanced ATP levels, respiratory rate, and V-ATPase activity. In addition, PoVHA-a3 expression led to greater accumulation of osmoprotectants (proline, soluble sugars and proteins), higher activities of antioxidant enzymes, and reduced levels of oxidative stress indices. Furthermore, a significantly lower shoot Na⁺/K⁺ ratio was observed in transgenic plants, indicating improved ion homeostasis. In conclusion, this study demonstrates that PoVHA-a3 acts as a pivotal positive regulator of salt tolerance in purslane, providing a valuable genetic resource for enhancing salt tolerance in crops through genetic engineering. Full article

The plant NAC (NAM, ATAF1/2, and CUC2) transcription factor family plays an important regulatory role in stress response. In this study, we analyzed the rice transcription factor OsNAC113 and elucidated its tissue-specific characteristics and stress response regulatory mechanisms. qRT-PCR results showed that under laboratory-simulated drought, high salt, temperature stress, and hormone treatments, such as abscisic acid (ABA) and gibberellic acid (GA₃), the expression level of OsNAC113 significantly changed, indicating that OsNAC113 responds to various stress conditions. Targeted creation of the rice (Oryza sativa L. spp. japonica) OsNAC113 (LOC_os08g10080.1) mutant based on the CRISPR-Cas9 genome editing strategy revealed its response to salt stress (200 mM). The growth status and survival rate of the mutant under high-salt stress were significantly higher than those of the wild type. Testing showed that the mutant exhibited increased relative water, chlorophyll, and soluble sugar contents under salt stress than the wild type. The malondialdehyde content in the mutant was lower, and the activities of superoxide dismutase, peroxidase, and catalase were higher than those in the wild type, indicating that the mutant with functional loss caused by knocking out OsNAC113 had a significantly enhanced tolerance to salt treatment. Using RNA-seq to detect genome-wide changes in OsNAC113 mutant materials under stress, KEGG annotation showed that knocking out OsNAC113 resulted in regulatory changes in “plant hormone signaling pathway” and “MAPK signaling pathway,” and GO and KEGG annotations showed significant changes in “amino acid transport and metabolism,” “carbohydrate transport and metabolism,” “lipid transport and metabolism,” and “replication, recombination, and repair.” OsNAC113 may be involved in the response to salt stress by regulating these signaling pathways. Using comparative metabolomic analysis, we further elucidated the function of OsNAC113 in physiological metabolic pathways. The knockout of OsNAC113 resulted in changes in various important metabolic pathways in plants, including flavonoid biosynthesis and ABC transporters. Therefore, it is suggested that OsNAC113 is involved in these metabolic processes and affects their regulation in high-salt environments. These results provide a theoretical foundation and reliable material for the molecular breeding of rice. Full article