Search Results (2,505)

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) regulates diverse aspects of plant growth and secondary metabolism, yet its concentration-dependent effects on rhizomatous spice crops remain poorly understood at the systems level. Here, we investigated the phenotypic, physiological, hormonal, and multi-omics responses of ginger (Zingiber officinale) to foliar-applied ABA across a concentration gradient. Exogenous ABA modulated ginger growth in a distinctly non-linear manner. Low-to-moderate concentrations (5–15 mg/L) significantly enhanced aboveground branching and belowground rhizome yield, whereas high concentration (35 mg/L) inhibited branching while promoting structural carbohydrate accumulation, revealing a concentration-dependent trade-off between growth and secondary wall deposition. Hormone profiling uncovered global reprogramming of the endogenous hormonal network, with optimal ABA (15 mg/L) coordinately elevating growth-promoting hormones and defense-related signals, while high concentrations suppressed multiple hormone pathways and triggered negative feedback inhibition of endogenous ABA biosynthesis. Integrated metabolomic and transcriptomic analyses identified convergent enrichment on phenylpropanoid biosynthesis, gingerol biosynthesis, and plant hormone signal transduction. Co-expression network analysis revealed a highly interconnected module of 583 genes linking hormone signaling to secondary metabolism, with coordinated up-regulation of key enzymes from phenylalanine ammonia-lyase (PAL) to polyketide synthase under 15 mg/L ABA explaining the 64% increase in 6-gingerol content. This study establishes a mechanistic chain from ABA perception to improved ginger yield and quality, mediated by hormonal crosstalk and transcriptional activation of the phenylpropanoid-gingerol network. We propose an “ABA optimization window” of 5–15 mg/L for precision cultivation of high-quality ginger, providing a systems-level framework for understanding hormone-mediated regulation of secondary metabolism in medicinal and spice crops. Full article

Shoot tip cryopreservation is essential for the long-term conservation of plant genetic resources. It provides the only reliable method for establishing a long-term, readily available gene pool of clonally propagated crops and elite in vitro clones used in the pharmaceutical, food, and cosmetic industries. Still, its success is often limited by the inherent sensitivity of many species to the osmotic and chemical stresses imposed by concentrated cryoprotectant (vitrification) solutions and severe dehydration. The optimization of modern cryopreservation protocols primarily focuses on modifying shoot tip preculture, cryoprotectant treatments, or regrowth conditions, while frequently overlooking donor plant preconditioning or relegating it to a secondary role. However, the physiological state of in vitro plants from which apical or axillary shoot tips are extracted may hold the key to successful post-cryopreservation recovery, especially in cryo-sensitive taxa. This review revisits the critical role of donor plant vigor and induced stress tolerance in the cryopreservation of clonal crops by systematically evaluating preconditioning strategies, including cold acclimation, sucrose pretreatment, and the use of growth regulators and signaling molecules such as abscisic, jasmonic, and salicylic acids, involved in stress signaling and tolerance development. The beneficial physiological changes induced by donor plant pretreatment, such as reduced freezable water content and the accumulation of protective compounds, are discussed in the context of contemporary cryopreservation methods. The effects of culture conditions, including the roles of ammonium and nitrates, light quality, culture density and aeration, medium strength, culture age, and subculture duration, are also considered. We analyze how different treatments of in vitro donor plants improve shoot tip tolerance to osmotic and/or chemical toxicity imposed by specific cryopreservation methods to support a material-centered selection of a cryopreservation procedure. Future directions and potential approaches for integrating target donor plant preconditioning into modern cryopreservation protocols for shoot tips, particularly in stress-sensitive species, are discussed. 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

Axillary bud germination in sugarcane is a critical agronomic trait that directly determines seedling emergence and tillering capacity; however, its molecular regulatory mechanisms remain poorly understood. In this study, we systematically investigated the hormonal dynamics and transcriptomic profiles of the sugarcane cultivar XTT22 across five developmental stages (from dormancy to the first new leaf stage). Our results revealed that abscisic acid (ABA) content fluctuated during germination, whereas indole-3-acetic acid (IAA) and gibberellin (GA) levels decreased significantly, suggesting their negative regulatory roles. In contrast, cytokinin (CTK) and ethylene (ETH) contents increased at the initiation stage, indicating positive promoting functions. Transcriptome analysis identified 31,513 differentially expressed genes (DEGs), which were significantly enriched in pathways related to hormone signal transduction, starch/sucrose metabolism, and photosynthesis. Weighted gene co-expression network analysis (WGCNA) constructed 12 co-expression modules, among which the antiquewhite4 module (negatively correlated with IAA, GA, and ABA contents) and the darkorange2 module (positively correlated with cytokinin content) were identified as key regulatory modules. From these modules, seven core hub transcription factors (e.g., ScTCP5, ScSCR, and ScSHR1) were screened, and their expression patterns were validated by RT-qPCR. Furthermore, the expression trends of six hormone-related DEGs were highly consistent with the RNA-seq data. Collectively, this study elucidates the hormonal dynamics and gene regulatory networks underlying axillary bud germination in sugarcane, providing candidate gene resources for breeding high-yield varieties with enhanced emergence and tillering capacity. Full article

The coordinated development of achenes and receptacles in strawberry is critical for seed dispersal and fruit quality, yet the underlying molecular mechanisms remain poorly characterized. Utilizing RNA-seq analysis during the ripening transition stage, we identified pronounced transcriptomic divergence between achenes and receptacles, with receptacles exhibiting more dynamic gene expression shifts. Intriguingly, a substantial subset of differentially expressed genes (DEGs) displayed antagonistic expression patterns between these tissues, including the cytokinin degradation gene cytokinin oxidase/dehydrogenase 1 (FvCKX1), which was highly expressed in both tissues but with opposing temporal trends. Functional interrogation via transient silencing and overexpression revealed a tissue-specific regulatory role for FvCKX1. RNA interference (RNAi) suppression of FvCKX1 significantly enhanced receptacle expansion but delayed achene maturation, whereas overexpression inhibited receptacle growth while accelerating achene ripening. Abscisic acid (ABA), which positively regulates fruit enlargement, was elevated in FvCKX1 RNAi receptacles and notably reduced in overexpression fruits, indicating that FvCKX1 might negatively modulate ABA synthesis during strawberry fruit development. Our results demonstrate that FvCKX1 may function as a key regulator mediating the coordinated development between achenes and receptacles in strawberry. Full article

Corolla movement is a typical plant movement behavior that enables plants to optimize pollination and adapt to environmental changes. Nevertheless, its molecular mechanism remains poorly understood. In the present study, we conduct a comprehensive transcriptome analysis of Mirabilis jalapa (Nyctaginaceae) corolla at five stages (AG-EG) to elucidate the regulatory networks underlying movement. The results showed that the differentially expressed genes (DEGs) were mainly associated with cellular processes, catalytic activity, MAPK signaling, plant hormone signal transduction, and photosynthesis-related pathways, highlighting their involvement in corolla dynamics. Transcriptome profiling further demonstrated that auxin, ethylene, and abscisic acid signaling pathways were key hormonal regulators of corolla movement. Moreover, Ca²⁺ transport genes (CNGCs and CMLs) and respiratory burst oxidase homologs (RBOHs) were significantly enriched, indicating that Ca²⁺–ROS signaling oscillations also play an important role in driving differential cell expansion and turgor changes. Transcription factor analysis also revealed the upregulation of WRKY2, WRKY22, and WRKY33, suggesting that WRKYs act as the critical transcriptional regulators linking ROS–Ca²⁺ signals with downstream gene expression. The reliability of RNA-Seq data was confirmed by RT-qPCR, which showed high consistency with transcriptome profiles. These findings suggested that corolla movement in M. jalapa is carried through the integration of hormonal pathways, Ca²⁺–ROS signaling, and WRKY-mediated transcriptional regulation. This research provided novel insights into the molecular basis of plant movement and established a foundation for further study on floral dynamics and adaptive strategies in angiosperms. Full article

Caladium bicolor is an important ornamental foliage plant; however, its tropical origin makes it highly sensitive to environmental stresses such as drought and low temperature, which limits its cultivation and industrial development. Basic helix–loop–helix (bHLH) transcription factors play key roles in plant responses to abiotic stresses, but their functions in C. bicolor remain largely unknown. Here, a bHLH transcription factor gene, CbbHLH35, was cloned from C. bicolor, and its sequence characteristics, subcellular localization, expression patterns, and potential roles in stress responses were analyzed. The results showed that CbbHLH35 contains a conserved bHLH domain and is localized in the nucleus. qRT-PCR analysis revealed that CbbHLH35 is expressed in different tissues, with the highest expression in tubers, and is significantly induced by methyl jasmonate (MeJA), abscisic acid (ABA), drought, and low-temperature treatments. Transgenic C. bicolor plants overexpressing CbbHLH35 were generated and subjected to drought and cold stress. Compared with control plants, the overexpression lines showed higher chlorophyll content and POD activity but lower electrolyte leakage and MDA content, indicating enhanced drought and cold tolerance. These results suggest that CbbHLH35 plays a positive role in regulating drought and cold tolerance in C. bicolor and represents a promising candidate gene for the molecular breeding of stress-resistant cultivars. Full article

Drought severely limits maize production. Basic helix-loop-helix (bHLH) transcription factors act as key regulators of plant drought responses; however, the precise regulatory networks they coordinate in maize remain largely unclear. Here, we functionally characterized ZmbHLH81, a drought- and abscisic acid (ABA)-responsive bHLH transcription factor in maize. Subcellular localization confirmed that ZmbHLH81 is a nuclear protein. Overexpression of ZmbHLH81 in Arabidopsis enhanced drought tolerance, whereas CRISPR/Cas9-mediated targeted mutagenesis in maize significantly increased plant sensitivity to drought stress. Physiologically, these mutant lines exhibited accelerated water loss, delayed stomatal closure, compromised antioxidant enzyme activities and elevated malondialdehyde (MDA) accumulation under drought stress. DAP-seq analysis demonstrated that ZmbHLH81 specifically recognizes the conserved G-box motif (CACGTG). Furthermore, integrating DAP-seq and transcriptomic data successfully identified the key downstream targets governed by ZmbHLH81. Molecular assays confirmed that ZmbHLH81 directly targets and transactivates the core ABA signaling kinase gene ZmSnRK2.9 and stress-responsive transcription factor genes ZmNAC20 and ZmHDZ4. Taken together, ZmbHLH81 positively regulates maize drought tolerance by directly activating a specific regulatory module that orchestrates ABA-mediated stomatal closure and reactive oxygen species (ROS) scavenging, providing a promising genetic target for breeding climate-resilient crops. Full article

Sulfated peptides, such as PSK, PSY, CIF, and RGF, are crucial regulators of plant growth, development, and stress responses, with their activity dependent on post-translational tyrosine sulfation by tyrosylprotein sulfotransferase (TPST). This study explores the evolutionary history and the interaction mechanisms between TPST and sulfated peptides in plants. Systematic analyses of multi-species genomes show that TPST can be traced back to the chlorophyte lineage, whereas PSK, a sulfated peptide, appears to have emerged in gymnosperms. TPST is evolutionarily conserved, typically present in low copy numbers across plant lineages, while its peptide substrates have expanded in angiosperms. In Liriodendron chinense, TPST-sulfated peptide gene promoters are enriched with cis-regulatory elements linked to abscisic acid, gibberellin responsiveness, and anaerobic induction. Synteny analyses revealed collinearity between sulfated peptide genes in L. chinense, Magnolia biondii, Arabidopsis thaliana, and Populus trichocarpa, but not with Oryza sativa. Molecular docking identified key TPST-PSK interaction sites in the sulfotransferase domain, with several critical residues facilitating binding. Transcriptomic and co-expression network analyses revealed that LcTPST was expressed at lower levels than its peptide precursor genes, while LcPSK2 remained highly expressed after the torpedo stage of somatic embryogenesis. Stress conditions significantly increased PSK-associated module connectivity, enriched in transcription factors such as WRKY, bHLH, bZIP, and MADS. This study provides insights into the evolutionary, structural, and regulatory aspects of the TPST-sulfated peptide system in plants. Full article

Background: PYR/PYL/RCAR proteins are core abscisic acid (ABA) receptors that play essential roles in ABA signal transduction, plant growth and development, and abiotic stress responses. However, the PYL gene family in watermelon (Citrullus lanatus) has not been systematically characterized, limiting our understanding of ABA-mediated stress adaptation in this economically important crop. Methods: A genome-wide analysis was performed to identify ClPYL genes in watermelon using a hidden Markov model search. Phylogenetic relationships were reconstructed using the maximum likelihood method. Segmental duplication events were analyzed using synteny analysis. Conserved motifs, gene structures, and promoter cis-acting elements were characterized using MEME and PlantCARE. Expression profiles under drought, salt, and cold stresses were examined by quantitative real-time PCR (qRT-PCR) with three biological replicates. Results: In this study, 15 ClPYL genes were identified in watermelon through genome-wide analysis. Phylogenetic reconstruction classified these genes into four subfamilies, with subfamily II being exclusively present in cucurbits—a lineage-specific feature not observed in Arabidopsis. Synteny analysis revealed eight segmental duplication events involving members of subfamilies I, III, and IV, while subfamily II members were not associated with these duplications. Members within the same subfamily share similar exon-intron structures and conserved motifs. Promoter analysis revealed that ClPYL genes are enriched with various cis-acting elements associated with hormone signaling and abiotic stress responses. Expression profiling demonstrated that ClPYL genes exhibit diverse and dynamic expression patterns under drought, high-salinity, and cold stresses. Notably, genes such as ClPYL5 under drought, ClPYL02 under salt, and ClPYL15 under cold stress displayed persistent stress-responsive expression. Conclusions: These findings reveal the evolutionary conservation and diversification of the PYL family in watermelon and provide a set of candidate genes for functional studies aimed at dissecting ABA-mediated stress adaptation. This work establishes a genomic framework for developing stress-resilient watermelon varieties through molecular breeding. Full article

Salt, drought and freezing stress were major abiotic factors limiting plant growth, development and yield. Halostachys caspica (Amaranthaceae), a halophyte native to saline-arid desert regions, tolerated multiple abiotic stresses, but its molecular mechanisms of stress tolerance remain unclear. By integrating the small RNA library and transcriptome data of H. caspica under high salinity, HcmiR172e was identified as a differentially expressed miRNA and selected for the study of multiple abiotic stress responses. Using its mature sequence (20 nt) to align with upregulated genes from the transcriptome, HcTOE3 (AP2 subfamily transcription factor belonging to the AP2/ERF family) was preliminarily predicted as its target gene through bioinformatic analysis. Our previous work demonstrated that HcTOE3 was strongly upregulated by multiple abiotic stresses, including salinity, drought, heat and low temperature. Furthermore, overexpression of HcTOE3 conferred freezing tolerance to Arabidopsis throughout the entire growth period. In this study, miRNA expression analyses showed that HcmiR172e was significantly downregulated in the assimilating branches of H. caspica under low temperature, heat, salt, drought, oxidative stress and abscisic acid (ABA) application. Tobacco transient expression assays and 5′RLM-RACE confirmed that HcmiR172e directly cleaved HcTOE3 transcripts in the region close to the 5′end of the ORF. HcmiR172e-overexpressing Arabidopsis displayed increased sensitivity to salt, drought, freezing stresses and ABA treatment, along with enhanced growth inhibition, elevated reactive oxygen species (ROS) accumulation, decreased osmolyte content and downregulation of stress-responsive genes. In contrast, HcTOE3-overexpressing Arabidopsis exhibited the opposite phenotypes, physiological responses and corresponding gene expression patterns under multiple stress treatments. These findings collectively elucidated the antagonistic regulatory roles of HcmiR172e and HcTOE3 in plant abiotic stress responses, providing novel molecular targets for engineering stress-tolerant crops for saline, arid, freezing environments. Full article

While “survival of the fittest” implies that competition is the main driver of evolution, cooperation and altruism are also widespread in nature, even among plants. This suggests that natural selection favors regulatory systems that balance competitive growth with restraint, depending on context. We propose that plant hormones are key mediators of this balance, acting along a spectrum from competition to cooperation. Based on evidence from developmental, ecological, and evolutionary studies, we classify major plant hormones by their roles in competitive behavior: auxin, gibberellins, and brassinosteroids drive competitive foraging and resource acquisition, while cytokinins, abscisic acid, strigolactones, ethylene, salicylic acid, and jasmonate are linked to growth restraint, resource conservation, and communal defense. This functional partitioning reflects a modular hormonal architecture that allows plants to adapt flexibly to their environment and social context. We explore how this classification could inform the use of plant hormones in agriculture and advance research in plant kin selection and inclusive fitness. Full article

To explore the application potential of insect-derived functional microorganisms in short-cycle leafy vegetable production, we evaluated the effects of Serratia marcescens BRC-CXG2, isolated from larvae of Monochamus alternatus, on romaine lettuce in a pot experiment. Plant growth traits, biomass accumulation, nutritional quality, endogenous hormones, and rhizosphere microbial communities were systematically evaluated. The results demonstrated that inoculation significantly promoted seedling development. Plant height and root length increased by 48.7% and 29.1%, respectively, while shoot and root dry weights were 1.78- and 1.85-fold higher than those of the control. Vitamin C and total sugar contents increased by 76.4% and 98%, respectively. The levels of gibberellins (GA₃)-, indole-3-acetic acid (IAA)-, and abscisic acid (ABA)-immunoreactive equivalents increased by 1.5-, 1.29-, and 1.75-fold. High-throughput 16S rDNA gene and ITS amplicon sequencing further revealed that inoculation reshaped the composition of bacterial and fungal communities in the rhizosphere. Collectively, these findings demonstrate that insect-derived S. marcescens exhibits significant growth-promoting potential in short-cycle leafy vegetable systems, with effects associated with hormone regulation, enhanced total sugar accumulation, and shifts in rhizosphere microbial community structure. Full article

The modulation of plant responses to abscisic acid (ABA) and/or abiotic stresses can be manipulated by the expression of ABA-responsive genes, which is affected by phytohormone ABA. While some ABA-responsive genes have been shown to regulate plant responses to ABA and/or abiotic stresses, the functions of numerous ABA-responsive genes remain unknown. Therefore, characterizing these unstudied genes would provide a practical way to identify novel regulators of plant adaptations to ABA and/or abiotic stresses. Here, we characterized four closely related unstudied ABA-responsive genes in Arabidopsis thaliana, named Arabidopsis thaliana ABA-up regulated genes (AtAUGs). We found that ABA treatment induces AtAUGs expression level, and our results in transfected protoplasts show that AtAUGs exhibit nucleus localization and downregulate the co-transfected reporter expression level. The results of ABA sensitivity assays, including seed germination, cotyledon greening, and root extension assay show that transgenic plants overexpressing AtAUGs had increased sensitivity, but ataugs mutants generated by isolating T-DNA insertion lines or through CRISPR/Cas9 gene-editing of AtAUGs had decreased sensitivity; in addition, the greatest decrease in ABA sensitivity was observed in the ataug1 ataug2 ataug3 ataug4 (ataug1234) quadruple mutants. The qRT-PCR results show that the expression levels of several Type 2C Protein Phosphatase (PP2C) genes, the key negative regulator genes of ABA signaling including PP2CA, Hypersensitive to ABA 1 (HAB1), HAB2, Highly ABA-Induced PP2C protein 3 (HAI3), ABA-Hypersensitive Germination 1 (AHG1), and ABA Insensitive 2 (ABI2) decreased in 35S:AtAUGs transgenic plants, but increased in the ataug1234 quadruple mutants. Taken together, these results suggest that AtAUGs are ABA-responsive genes, and AtAUGs positively regulate ABA responses in a redundant manner, by downregulating the expression of crucial negative regulator genes in ABA signaling. Full article