Search Results (10,016)

Soil salinization has become a major global constraint threatening ecosystem stability and agricultural production. As a prominent salt-tolerant turfgrass, Paspalum vaginatum (seashore paspalum) serves as an excellent material for exploring salt tolerance mechanisms. In this study, PvHAK12, a high-affinity K⁺ transporter (HAK) family gene isolated from seashore paspalum, was functionally characterized. PvHAK12 encodes a 788 amino acid protein with 13 transmembrane domains, belonging to the plasma membrane-localized ion transporters. It exhibits high sequence conservation with other HAK transporters and is predominantly expressed in roots and stems, with distinct tissue- and time-specific induction under salt stress. Yeast complementation assays revealed that PvHAK12 has no obvious K⁺ transport capacity but may mediate Na⁺ transport. Overexpression of PvHAK12 in Arabidopsis thaliana significantly reduced salt tolerance at germination, seedling and rosette stages, as reflected by lower germination rate, fresh weight, survival rate, the maximum quantum yield of photosystem II (Fv/Fm) value and chlorophyll content, accompanied by higher ion leakage. Under salt stress, transgenic plants accumulated more Na⁺ and less K⁺, leading to an elevated Na⁺/K⁺ ratio. Moreover, transgenic lines displayed weaker antioxidant enzyme activities and higher reactive oxygen species (ROS) accumulation. Transcript analysis further demonstrated that PvHAK12 overexpression suppressed the induction of multiple ion-transport and stress-responsive genes under salt conditions. These results indicate that PvHAK12 negatively regulates plant salt tolerance by disrupting ion homeostasis, antioxidant capacity and stress-related gene expression. Full article

Carbon dots offer excellent physico-chemical properties and biocompatibility for cancer theranostics systems, either as therapeutic agents themselves, or as potential drug carriers. It is, however, postulated that the drug carrier affects the mechanism of action and intracellular target molecules of a drug. Therefore, in the present study, we systematically evaluated protein alterations in HeLa cervical cancer cells after treatment with sulfur-doped carbon dots (S-CDs). Synchrotron Radiation μFTIR spectroscopy and label-free LC–MS/MS proteomics integrated with bioinformatics were used to assess molecular changes. μFTIR revealed a shift and increased intensity of α-helices, indicating structural changes in proteins as a result of the interaction between S-CDs and cells. Proteomic analysis identified 122 statistically significant (p ≤ 0.05) proteins with increased abundance and 61 with decreased abundance following S-CD exposure, many of which possess high α-helix content, consistent with μFTIR findings. Functional analyses showed that up-regulated proteins were enriched in molecular adaptor, transporter, and transcription regulator activities, particularly those involved in RNA metabolism and translation. Down-regulated proteins were dominated by protein-modifying enzymes and cytoskeletal components. Pathway enrichment analysis indicated alterations in mRNA processing, ribosomal pathways, translation factors, aminoacyl-tRNA biosynthesis, and proteasome degradation. Key hub proteins included ribosomal proteins and translation initiation factors. S-CD treatment led to opposite regulation of many proteins compared to their regulation in untreated HeLa cells including down-regulation of ribosomal proteins (RPS27L, RPS19, and RPS5), aminoacyl-tRNA biosynthesis proteins (IARS1, LARS1, and MARS1), and proteasome degradation proteins (PSMD2, PSMD3, and PSMD11), which aligns with the observed cytotoxic effect of S-CDs on cervical cancer cells. Overall, these results highlight significant proteomic and structural protein changes induced by S-CDs and support their potential for cervical cancer treatment, warranting further investigation of this nanomaterial’s biological applications. Full article

Flower senescence is a key physiological constraint on the ornamental and commercial longevity of cut roses. Although abscisic acid (ABA) is recognized as a promoter of this process, the molecular circuitry through which ABA operates, particularly the specific contributions of MYB transcription factors, remains largely unexplored. In this study, we identify RcMYB002 as a negative regulator of rose flower senescence. Transient overexpression of RcMYB002 significantly delays senescence, preserves anthocyanin accumulation, and modulates antioxidant enzyme activities in a time-dependent manner, consequently attenuating ABA-triggered oxidative stress. In contrast, silencing RcMYB002 accelerates senescence-associated phenotypes. At the molecular level, ABA suppresses RcMYB002 transcript accumulation, while yeast one-hybrid (Y1H) assays indicate that RcMYB002 interacts with the promoter regions of senescence-associated genes SAG12 and SAG21, consistent with a role in their transcriptional regulation. Taken together, our results support a model in which ABA promotes flower senescence by downregulating RcMYB002, thereby derepressing downstream senescence-executing genes. This work provides a molecular basis for understanding flower senescence and offers a potential target for extending rose vase life. Full article

Winter rapeseed (Brassica rapa L.) is an important crop for vegetable oil production in China. However, its productivity is frequently threatened by severe cold waves during winter. To investigate the role of the microtubule cytoskeleton in cold adaptation of winter rapeseed, a microtubule stabilizer paclitaxel (Tax) and a microtubule depolymerizer colchicine (Col) were sprayed on winter rapeseed and transgenic proBrAFP1 Arabidopsis, respectively. The mRNA levels of cold-induced genes, along with cell membrane stability, antioxidant enzyme activities, and hormone levels were assessed under cold stresses of 4 °C and −4 °C. The results showed that low temperature significantly activated the proBrAFP1 promoter activity and increased the mRNA levels of core cold signaling pathway genes, such as C-REPEAT BINDING FACTORS (CBFs), Cyclic Nucleotide-Gated Channel (CNGC), OPEN STOMATA 1 (OST1) and Inducer of CBF EXPRESSION 1 (ICE1). Notably, under low-temperature stress, exogenous application of the microtubule stabilizer Tax markedly suppressed proBrAFP1-driven reporter activity in transgenic Arabidopsis, with consistent inhibition observed across both stem and leaf tissues; meanwhile, the Tax application alleviated reactive oxygen species (ROS) accumulation and mitigated membrane damage. In contrast, under the same low-temperature stress, the Col treatment exacerbated oxidative stress, enhanced lipid peroxidation, and elevated membrane damage. Collectively, these findings establish that microtubule regulators play indispensable roles in the cold stress response of winter rapeseed. It provides new insights into the mechanism by which plant microtubule cytoskeleton regulators mediate the cold response. Full article

Secondary salinization in mulched drip-irrigated cotton fields of arid oasis–desert transition zones in Xinjiang imposes coupled root-zone constraints, including salt-induced aggregate structural degradation and ionic stress. However, field evidence remains limited on whether integrating a structure-oriented soil conditioner with humic acid can generate stable improvements across growing seasons. A two-year field experiment with a randomized block design (three replicates) was conducted to evaluate four treatments: control (CK), polyacrylamide (PAM, 30 kg ha⁻¹), humic acid (HA, 450 kg ha⁻¹), and PAM + HA. Soil physical and chemical properties and aggregate-size distribution were determined after harvest, while enzyme activities and root traits were assessed at the flowering–boll stage. Structural equation modeling (SEM) and random forest (RF) analysis were used to explore soil–root–yield linkages and identify key soil predictors associated with yield variation. Treatment effects were most evident in the 0–20 cm layer, with PAM + HA showing the greatest overall improvement. In the topsoil, PAM + HA lowered soil pH from 8.35 to 7.88 in 2024 (p < 0.05), increased soil organic carbon (SOC) to 4.29 g kg⁻¹ in 2025 (p < 0.01), and increased NO₃⁻–N to 25.51 and 30.27 mg kg⁻¹ in 2024 and 2025, respectively (both p < 0.05). PAM + HA also enhanced cellulase activity from 6.17 to 16.85 mg glucose g⁻¹ 72 h⁻¹ in 2024 and increased seed cotton yield to 6683.69 and 5996.89 kg ha⁻¹ in 2024 and 2025, with a 51.0% yield increase over CK in 2024. SEM showed that root development had the strongest direct positive effect on yield (β = 0.79, R² = 0.63; goodness of fit (GOF) = 0.74), while random forest identified alkaline phosphatase, cellulase, and NO₃⁻–N as the main yield predictors (out-of-bag R² (OOB R²) = 0.672, p = 0.01). This study elucidated the effects of the combined application of a structure-oriented soil conditioner and humic acid on the root-zone environment of mulched drip-irrigated cotton fields in arid regions, providing a theoretical basis for the coordinated regulation of soil structural improvement and nutrient activation in saline–sodic cotton fields. Full article

Multiple myeloma (MM) is an incurable plasma cell malignancy characterized by high metabolic activity, chronic endoplasmic reticulum stress, and persistent redox imbalance. Excessive immunoglobulin synthesis and adaptation to the hypoxic bone marrow microenvironment lead to sustained production of reactive oxygen species (ROS). Their excessive accumulation promotes genomic instability, disease progression, osteolytic bone disease, and resistance to therapy. Paradoxically, MM cells adapt to oxidative stress by activating antioxidant and metabolic defense mechanisms, including Nuclear factor erythroid 2-related factor 2 (NRF2)- and Heme Oxygenase 1 (HMOX1)-dependent pathways, metabolic reprogramming, and overexpression of ROS-scavenging enzymes such as peroxiredoxin 6 (PRDX6), allowing survival at the threshold of oxidative toxicity. Evidence indicates that biomarkers of oxidative stress—such as lipid and protein oxidation products, antioxidant enzyme activity, and the Oxidative Stress Score—correlate with disease stage, prognosis, and treatment response. Redox-modulating therapeutic strategies, including pharmacological ROS induction, inhibition of antioxidant defenses, and the use of natural pro-oxidant compounds, are emerging as promising adjuncts to standard MM therapies. Recent studies also highlight the gut microbiota as an indirect regulator of oxidative balance, immune modulation, and metabolic homeostasis in MM. This review summarizes current knowledge on oxidative stress in multiple myeloma, emphasizing its role in pathogenesis, drug resistance, biomarker development, and emerging therapeutic and supportive strategies. Full article

Immunosuppression is associated with impaired immune responses and increased susceptibility to disease, highlighting the need for safe and effective immunomodulatory strategies. Oligosaccharides derived from natural sources have attracted growing interest due to their bioactivity and regulatory effects on host immunity. The present study was designed to evaluate the immune-enhancing potential of Periplaneta americana oligosaccharides (PAOSs) and to explore their association with SCFA-producing gut microbiota and metabolic regulation in an immunosuppressed mouse model. PAOS administration significantly increased serum immunoglobulin levels (IgG and IgM), promoted the secretion of immunoregulatory cytokines (IFN-γ, IL-2, TNF-α, IL-10, and IL-4), and elevated the proportion of CD4⁺ T cells in the spleen. In addition, PAOSs alleviated oxidative stress by reducing malondialdehyde accumulation while promoting the activity of key antioxidant enzymes, such as superoxide dismutase, catalase, and glutathione peroxidase. Metabolomic analysis revealed that PAOSs altered host metabolic profiles, particularly enhancing pyrimidine metabolism. Furthermore, PAOSs markedly enriched short-chain fatty acid (SCFA)-producing bacteria, and elevated colonic short-chain fatty acid levels. These changes were closely associated with the observed improvement in immune function. Collectively, this study demonstrated that PAOSs exerted immunomodulatory effects through coordinated regulation of SCFA-producing gut microbiota and host metabolism, elucidating the mechanisms underlying the bioactivity of insect-derived oligosaccharides. Full article

Seed aging is a major constraint for plant establishment in arid and semi-arid ecosystems, where poor seed vigor directly limits species persistence and restoration success. Desert species are particularly vulnerable to storage- and stress-induced deterioration, yet practical strategies to recover germination capacity in aged seeds remain limited. This study aimed to quantify aging-induced losses in germination performance and to evaluate whether exogenous gibberellic acid (GA₃) can partially restore seed vigor through physiological, biochemical, and hormonal regulation. Fresh seeds (FS), naturally aged (NA), and artificially aged (AA) seeds of four desert species (Salsola affinis C.A.Mey., Trigonella arcuata C.A.Mey., Ceratocarpus arenarius L., and Alyssum desertorum Stapf) were exposed to graded GA₃ concentrations (0–500 mg L⁻¹). Germination indices (GP, GR, GI, VI), antioxidant enzymes (SOD, POD, CAT), lipid peroxidation (MDA), phytohormones (IAA, ABA, cytokinins), and multivariate trait relationships were assessed. Without GA₃, NA reduced germination potential by 22.8–33.6%, while AA caused more severe losses of 42.4–67.8%, depending on species. Germination rate declined by 15.7–32.5% under NA and 36.4–65.2% under AA. GA₃ application improved all germination indices up to 200 mg L⁻¹ (GA200), which increased GP by 22.8–32.0% and vitality index by 17.0–28.5% compared with GA₀, whereas GA500 showed diminishing returns. Aging suppressed antioxidant enzymes by 15–20% (NA) and 30–45% (AA) and increased MDA by up to 50%, while GA200 enhanced SOD, POD, and CAT and reduced MDA by 8–18%. Aging also reduced IAA and cytokinins (~28–50%) and increased ABA (27.7–77.4%), with GA200 partially restoring hormonal balance. In conclusion, GA₃ at an optimal dose (200 mg L⁻¹) partially reverses aging-induced physiological and hormonal constraints, improving germination and vigor, although recovery remains limited under advanced deterioration. Full article

White mold caused by Sclerotinia sclerotiorum (Lib.) de Bary continues to threaten yield and quality and remains a stubborn, sometimes unpredictable constraint in many cropping systems. The pathogen’s broad host range and its capacity to persist for years as sclerotia mean that fields can carry risk long after visible symptoms fade. Disease development is often driven by short windows of favorable temperature and moisture that promote germination and ascospore release and dispersal, while myceliogenic infection from soil-borne sclerotia can also initiate disease directly. Yet dependable control is still undermined by durable inoculum, limited stable host resistance, variable biocontrol performance, and shrinking chemical options together with fungicide resistance risk. Here we consolidate current understanding and ongoing uncertainties around sclerotial formation and germination cues, the environmental drivers that shape epidemic onset, and the processes governing host colonization, including the roles of cell wall-degrading enzymes, oxalic acid, and redox regulation, as well as the continuing debate over necrotrophic versus hemibiotrophic phases. Management is considered from a practical perspective, covering cultural risk reduction, forecasting-guided fungicide programmes supported by resistance-management principles, and biological control strategies targeting sclerotia. Across systems, the evidence points to the same lesson: single tactics rarely remain reliable under field variability, whereas integrated packages that reduce soil inoculum and align interventions with risk are more durable. Future priorities include resolving early infection events, improving prediction of carpogenic germination under changing climates, increasing the consistency of biocontrol, and accelerating resistance breeding supported by genomic resources. Full article

Human transglutaminases (hTGs) are Ca²⁺-dependent enzymes that catalyze protein crosslinking, deamidation and other post-translational modifications, thus acting as key stabilizers of tissue architecture and modulators of protein function across diverse physiological contexts. This family comprises eight catalytically active members, TG1-7, the blood coagulation factor FXIII, and the inactive structural protein Band 4.2 of the erythrocyte membrane. Recent structural and biochemical advances have refined our understanding of the molecular principles governing transglutaminase function. Thus, current evidence reveals how domain organization and catalytic architecture integrate calcium binding, nucleotide-dependent regulation in TG2 and proteolytic activation in selected isoforms to control enzymatic activity. In this review, we provide an updated and comprehensive overview of the active hTGs, combining structural, biochemical and functional data to explain how closely related enzymes achieve isoform-specific regulation and distinct biological roles. We further examine how disruption of these mechanisms contributes to human pathology, highlighting representative examples in autoimmunity, inherited disorders and complex diseases. By integrating recent biochemical and structural findings with disease-associated evidence, we aim to offer a coherent framework for understanding how TG regulation underlies their diverse biological functions and clinical relevance. Full article

Cotton, a globally vital cash crop, is severely constrained by V. dahliae. Lignin, a core structural component of plant cell walls, plays a crucial role in physical defense, with its biosynthesis regulated by hydroxycinnamoyltransferase (HCT)—a key enzyme in the phenylpropanoid pathway. However, the HCT gene family in upland cotton (Gossypium hirsutum) and its role in resistance to V. dahliae remain poorly understood. In this study, we performed a genome-wide identification of the HCT gene family in G. hirsutum, identifying 74 GhHCT genes that were classified into five evolutionary subfamilies. Bioinformatics analysis revealed that GhHCT proteins exhibit conserved functional domains but diverse gene structures, with promoter regions enriched in hormone-responsive and stress-responsive cis-acting elements. Expression profiling revealed that multiple GhHCT genes were significantly induced in response to V. dahliae infection. Three genes, GhHCT2, GhHCT35, and GhHCT47, showed significantly higher expression levels in resistant cultivars than in susceptible cultivars during early infection stages, suggesting pivotal roles in defense. These three candidate genes, which contain MeJA/SA-responsive elements in their promoters, may enhance resistance by regulating lignin synthesis to strengthen the cell wall barrier. In summary, this study provides the first comprehensive characterization of the HCT gene family in upland cotton. It identifies key candidates for improving resistance to V. dahliae, offering valuable genetic resources for molecular breeding. Full article

Seed coating technology is regarded as one of the optimal strategies to promote sustainable agricultural development. It can effectively optimize the physical and physiological characteristics of seeds, improve germplasm quality, and enhance crop resistance to abiotic and biotic stresses. Saline–alkali soils, characterized by high salinity and alkalinity, severely restrict plant growth and development. However, alfalfa, a high-quality leguminous forage, faces substantial challenges in large-scale popularization and cultivation in saline–alkali regions. At present, research on the application of microbial seed coating technology in alfalfa production under saline–alkali conditions remains insufficient, and relevant techniques and formulations still require optimization. Under field conditions, this study used a randomized complete block design with alfalfa as the research material. Different coating treatments combining plant growth-promoting rhizobacteria (PGPR), rhizobia, and extracellular polysaccharides (EPSs) were established to systematically investigate the effects of various coating formulations on alfalfa yield, nutritional quality, root system architecture, and rhizosphere soil properties. Meanwhile, high-throughput sequencing was employed to analyze shifts in rhizosphere soil microbial community structure. The results demonstrated that all microbial coating treatments exerted significant growth-promoting effects on alfalfa grown in saline–alkali soils, among which the T8 treatment (combined coating of rhizobia + PGPR + EPS) performed the best. This treatment not only significantly improved alfalfa yield and nutritional quality but also modified root system architecture and enhanced soil enzyme activities, soil nutrient contents, and soil physical structure, thereby creating a favorable growth environment for plants. Among the single microbial coating treatments, the combined coating of rhizobia and EPS outperformed other single treatments and exhibited favorable application potential. Sequencing results revealed that microbial seed coating treatments significantly increased the relative abundance of beneficial soil bacteria, decreased the abundance of harmful fungi, regulated rhizosphere microbial community structure, and consequently promoted improvements in alfalfa yield and quality by optimizing the plant growth microenvironment. The findings of this study provide important theoretical support for the popularization and application of microbial seed coating technology in crop cultivation in saline–alkali soils, offer a key reference for optimizing alfalfa-specific seed coating formulations for saline–alkali conditions, and are of great significance for promoting the efficient utilization of saline–alkali land resources and the development of ecological agriculture. Full article

To address the need for enhanced geotechnical performance in gravelly soil stabilization, this study investigated the synergistic effects of guar gum as an additive in enzyme-induced calcium carbonate precipitation (EICP) treatment. Through systematic experimentation combining unconfined compressive strength (UCS) tests, carbonate content quantification, and triaxial analysis, the mechanical behavior of treated soils was evaluated under varying EICP solution concentrations (0–2 mol/L) and curing durations. Results demonstrated that a 1.5 mol/L EICP solution achieved peak strength and carbonate precipitation before subsequent decline, while a 1% guar gum dosage optimized mechanical properties by balancing initial strength enhancement and precipitation efficiency. Scanning electron microscopy revealed microstructural mechanisms wherein guar gum provided heterogeneous nucleation sites for calcite crystals, while its interaction with EICP enabled dual-phase pore filling and interparticle bonding. This synergistic effect created a three-dimensionally reinforced matrix, significantly improving both UCS and unconsolidated undrained shear strength compared to native and EICP-only specimens. The findings establish a theoretical framework for regulating calcite precipitation patterns and enhancing cementation mechanisms in gravelly soil improvement, offering practical guidelines for foundation engineering applications through the combined use of guar gum and EICP. Full article

The effects of static magnetic field (SMF) treatment on the solid-state culture of Sanghuangporus vaninii (SV) were investigated to enhance metabolite production and bioactivity. SMF parameters including intensity, exposure duration, and temperature were optimized, and treatment at 4 mT for 2 h per day produced the most pronounced effects, increasing total flavonoid (TFC), polyphenol (TPC), and triterpenoid (TTC) contents by 61–438% compared with the control. Ultrasonic extraction and semi-preparative chromatography enabled the isolation of three key compounds: D-(+)-trehalose (1), 5,7-dihydroxy-3,4′-dimethoxyflavone (2), and pinolenic acid (3), all of which were elevated following SMF treatment. Importantly, SMF exposure was associated with enhanced inhibitory activities against enzymes relevant to chronic metabolic disorders. The overall inhibitory activities against α-amylase, α-glucosidase, pancreatic lipase, and xanthine oxidase increased by 6–28% compared with the control, reaching a maximum inhibition of 97.60 ± 0.17%. Preliminary in vitro screening at 100 μg/mL showed that compounds 1 and 2 inhibited both α-amylase and α-glucosidase, whereas compound 3 selectively inhibited pancreatic lipase. Subsequent IC₅₀ analysis confirmed that compound 2 under SMF treatment exhibited inhibitory activity comparable to acarbose against α-amylase (45.62 μg/mL vs. 52.18 μg/mL) and α-glucosidase (38.74 μg/mL vs. 35.42 μg/mL). In addition, compound 3 showed moderate inhibition of pancreatic lipase with an IC₅₀ value of 42.15 μg/mL. These findings suggest that SMF treatment may enhance metabolite production and in vitro enzyme inhibitory activity in S. vaninii. However, these results are limited to in vitro assays, and further studies including cellular and in vivo validation, toxicity assessment, and pharmacokinetic evaluation, are required before any therapeutic or industrial applications can be considered. Full article

Plant growth regulation is orchestrated by complex hormonal networks involving gibberellin and auxin signaling pathways. In this study, a comprehensive in silico approach was employed to comparatively evaluate the plant growth regulators (PGRs) forchlorfenuron (CPPU) and strigol (STG) against two key proteins from Arabidopsis thaliana: Gibberellin 3-beta-dioxygenase 2 (GA3Ox2), a rate-limiting enzyme in the biosynthesis of bioactive gibberellins, and the auxin signaling repressor IAA7. These targets were specifically selected because they represent critical regulatory nodes in two major hormonal pathways controlling plant growth: GA3Ox2 governs the final steps of gibberellin activation, while IAA7 modulates auxin-responsive gene expression through its interaction with Auxin Response Factors. Therefore, their combined analysis enables the evaluation of potential regulatory effects of PGRs on both gibberellin biosynthesis and auxin-mediated transcriptional control. Molecular docking analyses revealed that both ligands exhibited higher binding affinity toward GA3Ox2 than IAA7, with STG showing slightly more favorable binding energies (−7.91 kcal/mol for GA3Ox2 and −5.43 kcal/mol for IAA7) compared to CPPU (−7.18 and −4.79 kcal/mol, respectively). These results suggest a structural preference of both PGRs toward the gibberellin biosynthetic pathway. To further assess complex stability under near-physiological conditions, 100 ns molecular dynamics (MD) simulations were conducted using the CHARMM36m force field. Despite its slightly lower docking scores, CPPU demonstrated greater conformational stability, lower RMSD fluctuations, and more persistent hydrogen bonding patterns, particularly in complexes with IAA7. In contrast, STG induced more pronounced conformational rearrangements, although it promoted slightly more compact protein conformations in certain systems. Fourier-transform infrared (FTIR) spectroscopy supported the computational findings by confirming the presence of key functional groups responsible for hydrogen bonding and hydrophobic interactions. Collectively, the results indicate that although STG exhibits higher initial binding affinity, CPPU forms more dynamically stable complexes with both proteins. These findings suggest that CPPU may represent a more robust candidate for sustained modulation of auxin and gibberellin signaling pathways in plant growth regulation. Full article