Search Results (158)

Increasingly frequent and severe drought events restrict global agricultural productivity. As sessile organisms, cereal crops have evolved phenotypic plasticity, drawing on drought escape (DE) and drought avoidance (DA) strategies to balance survival and reproduction. While the mechanisms governing photoperiodic flowering and drought responses are well characterized individually, their molecular intersection remains poorly understood. This review summarizes recent advances in the crosstalk between these two pathways. We highlight the divergent roles of core genetic hubs, such as florigen regulation, GIGANTEA (GI), DELLA proteins, and dual-function transcription factors (e.g., ZmCCT, Ghd7, Ppd-H1), and the breeding-selected alleles, including Green Revolution variants, that can partly uncouple stress tolerance from developmental penalties, though trade-offs often remain. Furthermore, we examine the internal networks driving this crosstalk, including circadian clock phase shifts, sugar and energy signaling through the trehalose-6-phosphate (T6P)-SNF1-related protein kinase 1 (SnRK1) module, and the antagonistic balance within phytohormone networks centered on abscisic acid (ABA). Finally, we propose that integrating epigenetic stress memory, systemic root-to-shoot signaling, and targeted CRISPR/Cas promoter engineering provides a useful conceptual framework for breeding climate-resilient, yield-stable crops. Full article

Alternative splicing (AS) coupled with nonsense-mediated decay (NMD) is an important post-transcriptional mechanism that regulates the expression of many genes, including serine/arginine-rich (SR) proteins across eukaryotes. In plants, SR proteins participate in diverse developmental processes and stress responses, particularly in abscisic acid (ABA) signaling. However, the functional differences among individual splice isoforms of SR proteins remain poorly understood. Here, we investigated SCL30a, a plant-specific SR protein in Arabidopsis thaliana. By integrating third-generation long-read transcriptome sequencing, NMD stability assays, and subcellular localization analyses, we identified five alternatively spliced SCL30a transcripts. Among them, SCL30a.2 and SCL30a.3 contain premature termination codons (PTCs), display nucleocytoplasmic localization, and are rapidly degraded through the NMD pathway. In contrast, the other three isoforms, SCL30a.1, SCL30a.4, and SCL30a.5, retain an intact RS domain and localize exclusively to the nucleus. Functional analyses showed that SCL30a acts as a positive regulator of ABA signaling. Loss-of-function mutants of SCL30a displayed reduced ABA sensitivity in both root growth and seed germination assays, whereas complementation or overexpression of three stable isoforms of SCL30a (SCL30a.1, SCL30a.4, and SCL30a.5) enhanced ABA responsiveness. Transcriptome analysis further showed that the expression of a subset of ABA-related genes, particularly SnRK2.6, was significantly altered in ABA-treated scl30a mutants and SCL30a.1-OE lines compared with WT plants. In addition, genetic evidence showed that overexpression of SnRK2.6 rescued the ABA-insensitive phenotype of the scl30a mutant. Together, these findings suggest that SnRK2.6 may function as a candidate downstream component associated with SCL30a-mediated ABA responses. Full article

Sucrose non-fermenting 1-related kinase (SNRK) is an understudied serine/threonine kinase of the CAMKL family, known for its role in metabolic regulation and cell signaling. Despite its emerging relevance in various biological processes and diseases, the phosphoregulatory landscape of human SNRK (valid substrates or role of its phosphosites) remains unexplored and demands robust, large-scale, data-oriented approaches to predict the potential substrates. A comprehensive analysis of global human phosphoproteomics datasets was performed to systematically identify class I phosphosites on SNRK, along with their predicted upstream kinases, potential downstream substrates, and coregulated phosphoproteins. Our analysis resulted in the identification of 33 dark SNRK phosphosites, of which 19 were differentially regulated across an array of experimental conditions. Among them, S518 and S569, outside their kinase domain, were the most frequently regulated and co-occurred phosphosites under diverse conditions. Notably, S569 is predicted as a candidate autophosphorylation site of SNRK. In these contexts, coregulation analysis of proteins and their phosphorylation sites suggested associations of phospho-SNRK in cell cycle progression, chromatin organization, and DNA replication. Uncovering candidate upstream kinases and potential substrates for prioritized validation, this study provides the first comprehensive phosphoproteomic map of SNRK, serving as a foundation for future investigations into its signaling network associations and therapeutic approaches. Full article

Capsicum annuum is a Solanaceae crop that is sensitive to cold, which affects its growth and development upon prolonged exposure and ultimately reduces yield. In response, a complex regulatory network of cold-responsive genes is activated. Earlier studies have shown that SnRKs play a positive role in enhancing cold tolerance in different crops, including peppers; however, the underlying molecular mechanisms and downstream targets have yet to be fully elucidated. In this study, yeast hybrid screening using CaSnRK2.4 identified a potential interacting partner CaPDX1. The interaction between CaPDX1 and CaSnRK2.4 was further confirmed through Y2H, luciferase complementation, and bimolecular fluorescence complementation assays. Subcellular localization showed that CaPDX1 and CaSnRK2.4 are localized in the nucleus as well as in the cell membrane. Silencing of CaPDX1 through VIGS showed increased susceptibility of peppers to cold stress, negatively influenced antioxidant enzymatic activities, and increased relative electrolyte leakage and malondialdehyde levels. Conversely, transient overexpression of CaPDX1 in peppers enhanced cold tolerance by reducing the accumulation of REL and MDA. Ectopic expression of CaPDX1 in Arabidopsis thaliana significantly improved its cold tolerance, accompanied by enhanced activity of antioxidant enzymes and increased chlorophyll content. In summary, these results indicate that CaPDX1 is a positive regulator of cold tolerance in pepper, and its mechanism of action involves interaction with CaSnRK2.4 and the regulation of physiological and molecular responses in pepper under cold stress. 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

Soil salinization is a major threat to global crop production. Tartary buckwheat (Fagopyrum tataricum), valued for its hardiness in marginal environments, provides an excellent system for studying plant salt tolerance. Using an integrated multi-omics approach, we deciphered the physiological, metabolic, and transcriptional responses of Tartary buckwheat to prolonged NaCl stress. Physiological profiling confirmed membrane damage alongside osmotic adjustment via proline accumulation and a phased antioxidant response. Metabolomics revealed extensive reprogramming, with dynamic enrichment in pathways of flavonoid biosynthesis, lipid metabolism, and the TCA cycle. Transcriptomics delineated a time-specific cascade from early signaling to late defense activation. Critical regulators within ABA and MAPK signaling pathways showed fine-tuned, divergent expression; for instance, SnRK2.3 was suppressed while specific PP2Cs were induced, and FtMAPK10 was dramatically up-regulated. Integrated analysis demonstrated coordinated induction of osmoprotectant synthesis (e.g., galactinol and betaine pathways) and a rewiring of central carbon metabolism. Our findings reveal a sophisticated, multi-layered adaptation strategy in Tartary buckwheat, integrating enhanced osmolyte production, antioxidant defense, membrane remodeling, and metabolic reprogramming, orchestrated by key signaling networks. This study provides a comprehensive molecular framework for salt tolerance and identifies valuable genetic targets for improving crop resilience. Full article

Drought stress severely constrains plant growth and productivity. To mitigate water loss, plants primarily regulate stomatal aperture through the Abscisic acid (ABA) signaling pathway, where the Sucrose Nonfermenting 1-Related Protein Kinase 2 (SnRK2) family kinase Open Stomata 1 (OST1) acts as a central positive regulator. However, the upstream regulators that fine-tune OST1 activity remain incompletely characterized. Aliphatic Suberin Feruloyl Transferase (ASFT), a BAHD acyltransferase essential for suberin aromatic monomer biosynthesis, was previously uncharacterized regarding its function in leaves. Here, we report that ASFT negatively regulates drought tolerance in Arabidopsis thaliana by directly interacting with OST1 and inhibiting its autophosphorylation, thereby restricting stomatal aperture. Consistent with this, the asft mutant exhibited decreased water loss and enhanced survival under drought, whereas ASFT-overexpressing lines showed opposite phenotypes. BiFC, Co-IP and in vitro kinase assays confirmed that ASFT directly interacts with OST1 and suppresses its autophosphorylation, while dehydration-induced OST1 phosphorylation was elevated in the asft mutant. Genetic evidence confirmed that ASFT functions upstream of OST1. This study reveals a moonlighting role for this suberin biosynthetic enzyme in ABA signaling and provides a potential target for breeding drought-resistant crops. Full article

Aquaporins are key membrane proteins that mediate water transport in plants and are indispensable for maintaining cellular water homeostasis and normal physiological processes. This study investigated the function of SbPIP1-3, an aquaporin gene isolated from drought-tolerant Sorghum bicolor. Bioinformatics analysis, subcellular localization, and heterologous expression of SbPIP1-3 were performed in Saccharomyces cerevisiae, Arabidopsis thaliana, and rapeseed. Sequence analysis revealed that SbPIP1-3 encodes a basic hydrophobic protein targeted to the plasma membrane, a finding further corroborated by subcellular localization assays. In yeast expression assays, SbPIP1-3-transformed strains retained viability under osmotic stress induced by 1.2 M mannitol, whereas non-transgenic control strains failed to survive. In Arabidopsis and rapeseed experiments, the SbPIP1-3 overexpression enhanced drought tolerance (improved germination, root growth, antioxidant enzyme activity, proline content, PSII repair capacity, and survival after drought–rewatering) and reduced intracellular H₂O₂ accumulation. Transcriptome profiling of drought-stressed transgenic Arabidopsis and control plants demonstrated significant upregulation of mostly stress-responsive pathways (e.g., MAPK signaling pathway and hormone signaling pathways) and key drought-tolerance genes (e.g., SNRK2-2, SOD1, APX3, GPX3, P5CS1). Collectively, these findings suggest that SbPIP1-3 enhances plant drought tolerance through the following mechanisms: improving transmembrane water transport efficiency to sustain cellular osmotic balance; activating the antioxidant defense system to increase enzyme activity and mitigate reactive oxygen species (ROS) accumulation; optimizing photosynthetic protection mechanisms to preserve the structural and functional integrity of PSII; and regulating the expression of stress-responsive signaling pathways and associated functional genes. Full article

The Xinjiang wheat variety ‘Xindong 22’ was used as experimental material. Two soil moisture treatments were established: control (CK, 70–75% field capacity), drought (X1, 60–65%). The photosynthetic characteristics and resistance physiological indexes of wheat leaves under different stress levels were analyzed, and RNA-Seq technology was used to conduct transcriptome sequencing and analysis were performed on wheat leaves. The results showed that under drought stress, superoxide dismutase (SOD) activity was significantly enhanced, while peroxidase (POD) activity decreased. Soluble sugar and proline contents also increased. These changes likely enhanced reactive oxygen species scavenging, thereby reducing the content of malondialdehyde in the leaves. Meanwhile, under the X1 treatment, stomatal conductance and transpiration rate of wheat leaves showed a slow decreasing trend, the intercellular CO₂ concentration decreased slightly, the decline in Fv/Fm was relatively small, and the value of the non-photochemical quenching coefficient gradually increased. Transcriptome analysis identified 1881 differentially expressed genes (DEGs). Notably, drought stress induced the up-regulation of key genes involved in the ABA signaling pathway (e.g., SnRK2 and ABF) and the MAPK cascade, suggesting their crucial roles in mediating drought responses in this wheat variety. In the jasmonic acid signaling pathway, MYC2 functions as a positive regulator by interacting with JAZ proteins. These findings demonstrate that Xinjiang wheat employs integrated physiological and molecular strategies to cope with drought stress. Full article

Under global climate change, cabbage (Brassica oleracea var. capitata), a major vegetable crop, is increasingly exposed to intermittent and fluctuating drought stress. A multi-level investigation of its adaptive strategies under water-deficit conditions is therefore essential for a comprehensive understanding of drought tolerance and for accelerating genetic breeding programs. In this study, the drought-resistant cultivar ‘ZG-628’ and the drought-sensitive cultivar ‘ZG-21’ were selected based on seed germination indices. Integrated physiological measurements, transcriptomic profiling, and metabolomic analyses were conducted to systematically compare their responses to drought stress. The results showed that the drought-resistant genotype ‘ZG-628’ maintained better water status, exhibited higher antioxidant enzyme activities, and accumulated greater levels of osmotic regulators under drought conditions. In addition, ‘ZG-628’ preserved higher chlorophyll content and photosynthetic efficiency than the sensitive genotype. At the molecular level, ‘ZG-628’ primarily responded to drought through key components of the abscisic acid (ABA) signaling pathway, including PYL, PP2C, and SnRK2. Metabolomic analysis further revealed preferential accumulation of flavonoids and ABA-related metabolites ‘ZG-628’, accompanied by specific activation of the “flavonoid and flavonol biosynthesis” pathway. Integrated multi-omics analysis indicated that plant hormone signal transduction was the most significantly enriched pathway among drought-responsive differentially expressed genes. Overall, this study systematically elucidates the coordinated multi-omics mechanisms underlying drought resistance in cabbage and provides both a theoretical basis and potential molecular targets for breeding drought-tolerant cabbage varieties. Full article

With the intensification of global climate change and the frequent occurrence of extreme drought events, forest production is facing severe challenges. This study imposed drought stress and exogenous abscisic acid (ABA) treatment on Larix gmelini seedlings, evaluated their physiological characteristics, and analyzed the transcriptional response mechanism using transcriptome sequencing. The results showed that drought stress induced organ-specific changes in superoxide dismutase (SOD) and peroxidase (POD) activities, malondialdehyde (MDA) accumulation, and soluble protein content. SOD activity in leaves significantly increased, while POD activity, MDA content, and soluble protein levels in roots exhibited more dynamic changes. After ABA application, SOD activity in leaves reached its peak at 24 h, which was opposite to the situation in roots and stems, where POD activity was highest at 24 h. At 48 h, MDA accumulation was most significant in roots, while the early response in leaves was minimal. At 24 h, the soluble protein increase was most significant in stems. In addition, at this time point, ABA application significantly increased the soluble protein content in all three organs. Transcriptome sequencing analysis further identified core response genes involved in the MAPK signaling pathway, plant hormone signal transduction, starch and sucrose metabolism, and flavonoid biosynthesis pathways, including SNRK2, MAPKKK17, PYL, PP2C, XRN4, TMEM, TIR1, and TGA. In summary, Larix gmelini seedlings alleviate the inhibitory effect of drought stress on growth through a synergistic mechanism, specifically by activating the antioxidant system, initiating the MAPK signaling pathway, regulating plant hormone signal transduction, and reshaping carbon metabolism pathways, thereby enhancing stress resistance. Full article

Tomato spotted wilt virus (TSWV) is one of the most important plants segmented negative-strand RNA viruses (NSVs). Plants employ the ubiquitin–proteasome system (UPS) and autophagy pathways to degrade viral effector proteins, forming a key antiviral defense layer. SnRK1 functions as a central energy sensor and plays pivotal roles in plant growth and development, as well as immune defense. However, whether SnRK1 modulates the infection of plant segmented NSVs and the underlying regulatory mechanisms remains elusive. In this study, we found that nonstructural protein NSs, a viral suppressor of RNA silencing (VSR) encoded by TSWV, specifically interacts with the catalytic α subunit of host SnRK1 (SnRK1α). NbSnRK1α promotes the degradation of NSs via the 26S proteasome pathway, independently of autophagy. Transient silencing of NbSnRK1α led to increased accumulation of the NSs protein. Furthermore, we found that NbSnRK1α significantly impairs the VSR activity of NSs by promoting its degradation, thereby restoring the host’s RNAi-mediated antiviral defense. Subsequent viral infection assays confirmed that NbSnRK1α inhibits TSWV replication, whereas silencing NbSnRK1α enhances the susceptibility of Nicotiana benthamiana to TSWV infection and facilitates systemic viral spread and disease symptom development. Our study uncovers a new antiviral defense case by which NbSnRK1α enhances host antiviral immunity through targeting a segmented negative-strand RNA viral effector for 26S proteasomal degradation, broadening the understanding of the NbSnRK1’s role in broad-spectrum antiviral defense. Full article

Drought severely limits plant growth, threatening global food security and biodiversity. This review provides a comprehensive overview of the recent advances in plant responses to drought, ranging from initial sensing to physiological adaptation, as well as guidelines for experimental design. We focus on key regulatory components, specifically the ABA signaling core (PYR/PYL/RCARs, PP2C phosphatases, and SnRK2 kinases) and ROS signaling. We provide a detailed description of transcriptional networks, highlighting the pivotal roles of DREB, NAC, and MYB transcription factors in coordinating gene expression. Furthermore, we explore downstream tolerance strategies, including osmoprotectant (e.g., proline) accumulation, cell wall remodeling involving expansins and pectin methylesterases, as well as stomatal regulation. We also discuss how combining genetics with multi-omics and high-throughput phenotyping bridges the gap between molecular mechanisms and whole-plant physiological performance. Ultimately, these insights provide a foundation for refining research approaches and accelerating the development of drought-resilient crops to sustain agricultural productivity and ecosystem stability in increasingly arid environments. Full article

Leaf abscission is a cell separation process that occurs throughout the entire plant life cycle, leading to the detachment of tissues or organs. The application of chemical defoliants to induce cotton leaf abscission not only saves the energy required for maintaining life processes but also facilitates mechanical harvesting. However, the molecular mechanisms underlying cotton leaf abscission remain poorly understood. In this study, multiple comparative analyses of gene expression differences were conducted between two cotton cultivars with different sensitivities to chemical defoliant Thidiazuron (TDZ) after TDZ application, resulting in 1,505,720,260 clean reads together with the average 92.77% of Q30 base percentage and 43.13% of GC content. A total of 35,739 differentially expressed genes (DEGs) were identified and these DEGs were mainly enriched in pathways of zeatin biosynthesis, secondary metabolite biosynthesis, and hormone metabolic processes. Integration of temporal expression pattern analysis and weighted gene co-expression network analysis (WGCNA) revealed that plant hormone signal transduction and MAPK signaling pathways might play important roles in TDZ-induced leaf abscission. Among them, a sucrose non-fermenting 1 (SNF1)-related protein kinase 2 gene (SnRK2, GH_A11G1981 and GH_D11G2017) in the abscisic acid (ABA) signaling pathway might be a potential key regulatory factor in defoliant induced leaf abscission. These findings provide novel insights into understanding the molecular mechanisms of chemical defoliant-induced leaf abscission in cotton and lay a foundation for future breeding programs and practical applications in cotton production. Full article

Protein post-translational modifications (PTMs), as an important biological process of plants responding to environmental stimuli, can regulate the chemical decoration and properties of translated proteins by altering amino acid side chains or protein terminal structures, thereby affecting the synthesis, assembly, localization, function, and degradation of proteins. Notably, PTMs regulate protein function without changing protein expression levels. Two dozen types of PTMs have been identified. This review summarizes the molecular mechanisms of major types of PTMs, including phosphorylation, ubiquitination, SUMOylation, glycosylation, methylation, and acetylation, with a focus on their regulatory roles in plant responses to abiotic stresses. Under heat stress, phosphorylation activates transcription factors such as HSFA1 (heat shock transcription factor 1), while SUMOylation regulates the activity of HSFA1/HSFA2 in the heat stress signaling pathway. Upon cold stress, phosphorylation, ubiquitination, and S-acylation collectively regulate the expression of cold tolerance-related genes. The drought stress response relies on SnRK2s (Sucrose 321 non-Fermenting 1-related protein kinase 2s) -mediated phosphorylation, regulation of ARF7 (auxin response factor 7) by SUMOylation, and ubiquitination. In salt stress, the coupling of phosphorylation of SOS (salt overly sensitive) pathway-related proteins, ubiquitination, and phospholipid metabolism maintains ion homeostasis. Additionally, PTMs play a key role in ABA-mediated abiotic stress responses by regulating core components of signal transduction, such as PYR (pyrabactin resistance)/PYL (PYR1-LIKE)/RCAR (regulatory components of ABA receptor) receptors, PP2Cs (protein phosphatases type 2C), and SnRK2s. On the basis of the synthesis of the regulatory mechanisms of PTMs, we discuss how PTMs can be manipulated to breed abiotic stress resilient crops and the issues to be addressed to achieve the goal, such as crosstalk between PTMs, technical challenges in investigating PTMs and identifying PTM substrates. Full article