Search Results (185)

Sorghum is an important cereal crop. The maintenance of leaf color significantly influences sorghum growth and development. Although the mechanisms of leaf color mutation have been well studied in many plants, those in sorghum remain largely unclear. Here, we identified a sorghum gradient-pale-green leaf mutant (sbgpgl1) from the ethyl methanesulfonate (EMS) mutagenesis mutant library. Phenotypic, photosynthesis-related parameter, ion content, transcriptome, and metabolome analyses were performed on wild-type BTx623 and the sbgpgl1 mutant at the heading stage, revealing changes in several agronomic traits and physiological indicators. Compared with BTx623, sbgpgl1 showed less height, with a smaller length and width of leaf and panicle. The overall Chl a and Chl b contents in sbgpgl1 were lower than those in BTx623. The net photosynthetic rate, stomatal conductance, and transpiration rate were significantly reduced in sbgpgl1 compared to BTx623. The content of copper (Cu), zinc (Zn), and manganese (Mn) was considerably lower in sbgpgl1 leaves than in BTx623. A total of 4469 differentially expressed genes (DEGs) and 775 differentially accumulated metabolites (DAMs) were identified by RNA-seq and UPLC-MS/MS. The results showed that sbgpgl1 primarily influenced sorghum metabolism by regulating metabolic pathways and the biosynthesis of secondary metabolites, especially flavonoids and phenolic acids, resulting in the gradient-pale-green leaf phenotype. These findings reveal key genes and metabolites involved on a molecular basis in physiological variations of the sorghum leaf color mutant. Full article

The functional role of MAPKK genes in potato (Solanum tuberosum L.) under high-temperature stress remains unexplored, despite their critical importance in stress signaling and yield protection. We characterized StMAPKK1, a novel group D MAPKK localized to plasma membrane/cytoplasm. Quantitative real-time polymerase chain reaction (qRT-PCR) revealed cultivar-specific upregulation in potato (‘Atlantic’ and ‘Desiree’) leaves under heat stress (25 °C, 30 °C, and 35 °C). Transgenic lines overexpressing (OE) StMAPKK1 exhibited elevated antioxidant enzyme activity, including ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), mitigating oxidative damage. Increased proline and chlorophyll accumulation and reduced oxidative stress markers, hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), indicate improved cellular redox homeostasis. The upregulation of key antioxidant and heat stress-responsive genes (StAPX, StCAT1/2, StPOD12/47, StFeSOD2/3, StMnSOD, StCuZnSOD1/2, StHSFA3 and StHSP20/70/90) strengthened the enzymatic defense system, enhanced thermotolerance, and improved photosynthetic efficiency, with significant improvements in net photosynthetic rate (Pn), transpiration rate (E), and stomatal conductance (Gs) under heat stress (35 °C) in StMAPKK1-OE plants. Superior growth and biomass (plant height, plant and its root fresh and dry weights, and tuber yield) accumulation, confirming the positive role of StMAPKK1 in thermotolerance. Conversely, RNA interference (RNAi)-mediated suppression of StMAPKK1 led to a reduction in enzymatic activity, proline content, and chlorophyll levels, exacerbating oxidative stress. Downregulation of antioxidant-related genes impaired ROS scavenging capacity and declines in photosynthetic efficiency, growth, and biomass, accompanied by elevated H₂O₂ and MDA accumulation, highlighting the essential role of StMAPKK1 in heat stress adaptation. These findings highlight StMAPKK1’s potential as a key genetic target for breeding heat-tolerant potato varieties, offering a foundation for improving crop resilience in warming climates. Full article

Copper pyrithione (CuPT), an emerging biocide used in ship antifouling coatings, may accumulate in marine sediments and pose risks to non-target organisms. However, current research on CuPT toxicity remains limited. Litopenaeus vannamei, one of the world’s most important aquaculture shrimp species, relies heavily on its hepatopancreas for energy metabolism, detoxification, and immune responses. Due to their benthic habitat, these shrimps are highly vulnerable to contamination in sediment environments. This study investigated the toxicological response in the hepatopancreas of L. vannamei exposed to CuPT (128 μg/L) for 3 and 48 h. Terminal deoxynucleotidyl transferase dUTP Nick-End Labeling (TUNEL) fluorescence staining revealed increased apoptosis, deformation of hepatic tubule lumens, and the loss of stellate structures in the hepatopancreas after CuPT 48 h exposure. A large number of differentially expressed genes (DEGs) were identified by transcriptomics analysis at 3 and 48 h, respectively. Most of these DEGs were related to detoxification, glucose transport, and immunity. Metabolomic analysis identified numerous significantly different metabolites (SDMs) at both 3 and 48 h post-exposure, with most SDMs associated with energy metabolism, fatty acid metabolism, and related pathways. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of metabolomics and transcriptome revealed that both DEGs and SDMs were enriched in arachidonic acid metabolism, fatty acid biosynthesis, and glycolysis/gluconeogenesis pathways at 3 h, while at 48 h they were enriched in the starch and sucrose metabolism, amino sugar and nucleotide sugar metabolism, and galactose metabolism pathways. These results suggested that CuPT disrupts the energy and lipid homeostasis of L. vannamei. This disruption compelled L. vannamei to allocate additional energy toward sustaining basal physiological functions and consequently caused the accumulation of large amounts of reactive oxygen species (ROS) in the body, leading to apoptosis and subsequent tissue damage, and ultimately suppressed the immune system and impaired the health of L. vannamei. Our study elucidates the molecular mechanisms of CuPT-induced metabolic disruption and immunotoxicity in L. vannamei through integrated multi-omics analyses, providing new insights for ecological risk assessment of this emerging antifoulant. Full article

Glaciers are significant sources of fresh water on planet Earth. The Hindukush–Karakoram–Himalayan (HKH) glaciers provide the water supply to more than half of the human population of the globe, for agricultural activities, biodiversity survival, and ecosystem services. In recent years, the loss of glacial ice has been forecasted to cause problems such as sea level rise, changes in water availability, and release of contaminants that reside in the surfaces of glaciers or within them. In this regard, mineralogical sediments play a significant role in the geochemistry of glaciers and element cycling. This study analyzed elemental pollutants found in the glaciers of Pakistan and investigated the diverse bacterial communities residing therein. Samples of ice and sediments were collected from the Gilgit, Hunza, and Swat glaciers in northern Pakistan. Nine elements, including co-factors, heavy metals, and nutrients, were assessed using atomic absorption spectrophotometry. The research findings indicate higher concentrations of the elements K, Fe, Cu, and Cr in Hunza glacier ice (Hgi) and Ni, Zn, As, and Cd in Gilgit glacier ice (Ggi). In terms of glacier sediments, Swat (Sgs), Gilgit (Ggs), and Hunza (Hgs) samples showed the highest concentrations of K, Cu, Ni, Zn, As, Pb, Cd, and, respectively, of Fe, and Cr. The amount of Cu and Cr is the same in Swat glacier ice and Swat glacier foot. However, the concentration of some elements (As, K, Pb, Zn) is higher in Swat glacier ice, while the amount of some elements (Cd, Ni) is greater in Swat glacier foot. Furthermore, microbial cultivation techniques revealed diverse bacterial communities inhabiting the sampled glaciers. Phylogenetic analysis of the bacterial isolates, based on 16S rRNA gene sequences, showed high homology (99–100%) with previously reported species. The resultant phylogenetic tree grouped the bacterial isolates, such as Serratia marcescens, Cupriavidus sp., and Bacillus cereus, with closely related species known for their roles in nutrient cycling, environmental resilience, and metal tolerance. These findings highlight the ecological significance and adaptive potential of microbial communities in glacier environments, emphasizing their role in elemental cycling and environmental resilience. Full article

Potato (Solanum tuberosum L.) is a major staple crop globally, yet its production is severely impacted by common scab, a disease caused by Streptomyces spp., leading to substantial economic losses. This study evaluated copper sulfate (CuSO₄) and zinc sulfate (ZnSO₄) as potential control agents for common scab, focusing on their antimicrobial properties and effects on potato resistance mechanisms. Both CuSO₄ and ZnSO₄ exhibited dose-dependent inhibition of Streptomyces spp., significantly reducing the production of the pathogenic toxin Thaxtomin A by 57.02% and 41.29%, respectively. Electrical conductivity assays indicated their disruptive effects on cell membrane integrity, and HPLC confirmed their suppression of toxin production. Pot experiments showed that these treatments enhanced plant growth, chlorophyll content, and defense enzyme activities (SOD, POD, CAT, PPO), while reducing malondialdehyde (MDA) levels. qPCR analysis revealed upregulation of defense-related genes (PR1, PR3, PR9, SOD1, HSF1). Field trials demonstrated disease control efficiencies of 56.58% and 59.06% for CuSO₄ and ZnSO₄, respectively, with ZnSO₄ increasing yield by 19.29%. These findings highlight CuSO₄ and ZnSO₄ as effective agents for suppressing Streptomyces spp. and enhancing potato resistance, offering practical value for sustainable potato production systems. Full article

The auxin efflux transporter PIN protein plays a crucial role in the asymmetric distribution of auxin on the plasma membrane, influencing the growth and development of plant organs. In this study, we identified nine members of the PIN gene family in the cucumber genome, which could be classified into five phylogenetic groups. These genes have diverse structures but conserved transmembrane domains. Analysis of cis-acting elements in the promoters revealed that CsPINs contain 48 types of cis-acting elements, predominantly light-responsive elements and plant hormone response elements. In addition, PIN proteins may interact with a variety of auxin-related proteins (including auxin response factor, auxin binding protein, mitogen-activated protein kinase PINOID, etc.) to jointly regulate the auxin synthesis and metabolic pathways. We analyzed the expression profiles of PIN genes in 23 tissues of cucumber using the CuGenDB database, and further investigated the expression levels of PIN genes in leaves and roots in response to different abiotic stresses and hormone treatments by qRT-PCR. This study provides a theoretical basis for clarifying the regulatory mechanism of the cucumber PIN gene family during environmental stress processes. Full article

Background: Soil heavy metal pollution by chromium (Cr) and copper (Cu) is a global environmental concern. Methods: This study evaluated Cr/Cu accumulation in Paulownia fortunei tissues and analyzed its root transcriptome under Cr and Cu stress to elucidate molecular response mechanisms. Results: Findings revealed significantly higher Cr and Cu accumulation capacity in roots compared to stems and leaves. Transcriptome sequencing identified 6017 and 2265 differentially expressed genes (DEGs) under Cr and Cu stress, respectively. These DEGs were primarily involved in redox reactions, stress responses, transcriptional regulation, transmembrane transport, and metabolism. Quantitative PCR of 20 selected genes validated dynamic expression changes under stress. Weighted Gene Co-expression Network Analysis (WGCNA) identified distinct co-expression modules associated with Cr and Cu. Hub gene analysis implicated Pfo_020668 and Pfo_019190 in Cr response, while Pfo_010312 and Pfo_000197 may enhance Cu tolerance via cell wall polysaccharide synthesis regulation. Pathways related to pyruvate metabolism and proteasome were significantly enriched under Cr stress, whereas amino acid metabolism pathways were prominent under Cu stress. Conclusions: Differentially expressed transporter genes suggest potential roles in heavy metal uptake and transport. This transcriptomic analysis provides novel insights into P. fortunei’s molecular responses to Cr and Cu stress, offering a foundation for utilizing this species in soil phytoremediation efforts. Full article

Post-traumatic stress disorder (PTSD) is a complex psychiatric condition characterized by persistent behavioral and neurobiological alterations following trauma. Although rodent models are commonly used to study PTSD, zebrafish (Danio rerio) have emerged as a promising alternative due to their genetic similarity to humans, conserved stress response systems, and high-throughput capabilities. This systematic review evaluates 33 experimental studies on zebrafish PTSD models, focusing on behavioral, neurochemical, and molecular outcomes. Chronic unpredictable stress (CUS/UCS) paradigms of 14–15 days were identified as the most reliable for inducing PTSD-like phenotypes, consistently resulting in anxiety-like behaviors, cortisol dysregulation, and gene expression changes. In contrast, acute stress models produced transient effects, and social defeat paradigms showed methodological variability. Chronic models frequently demonstrated neurotransmitter imbalances, oxidative stress, and upregulation of inflammatory and neuroplasticity-related genes. However, the literature revealed challenges, including protocol heterogeneity, limited sex-specific analyses, and constraints in longitudinal biomarker tracking. Future directions include epigenetic profiling, environmental standardization, and cross-species validation. When used with methodological rigor, zebrafish offer a powerful and translationally relevant platform to study PTSD mechanisms and screen novel interventions. Full article

Theanine, a unique non-protein amino acid, is specifically accumulated in tea plants during winter. This study explored the theanine accumulation patterns in ‘Longjing 43’ and ‘Huangjinya’ under different N supply conditions and analyzed the expression of genes involved in theanine biosynthesis during winter dormancy. We found that the two tea plant cultivars shared similar theanine accumulation patterns in winter. After 30 d of cultivation with various N forms and N deficiency, the theanine content in the tissues of both cultivars was highest in the control group, followed by NH₄⁺ treatment. Furthermore, we noted that root growth of tea plants was inhibited to varying degrees under different N sources and N-deficient conditions. Gene expression analysis revealed that both N forms can induce the transcription of key genes, including CsADC, CsALT, CsCuAO, CsGDH2, CsPAO, CsNiR, CsNR, and CsTS1 in ‘Longjing 43’ and ‘Huangjinya’. The expression of these genes was strongly correlated with theanine levels under the N treatments. The winter theanine accumulation was finely tuned by the interplay of multiple related genes, with expression levels varying across different cultivars and tissues. Full article

Zizyphus jujuba Mill. cv. Goutou is an edible and medicinal fruit whose development significantly impacts the metabolism and accumulation of nutrients and is regulated by plant hormones. In this study, the metal element and triterpene acid content were investigated and transcriptomic analyses were conducted to evaluate changes in seven ripening stages (Stages I–VII) of Z. jujuba Mill. cv. Goutou. We first analyzed seven metal elements and found that the concentrations of Magnesium (Mg), Aluminum (Al), Calcium (Ca), Manganese (Mn), and Cuprum (Cu) were highest at Stage I; in comparison, the concentrations of Zinc (Zn) and Ferrum (Fe) were highest at Stage IV. Additionally, three triterpene acids were detected in the fruits, with the contents of betulinic acid and oleanolic acid being highest at Stage VII and that of ursolic acid being highest at Stage I. Subsequently, through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations, we identified 40, 18, 9, 6, and 11 differentially expressed genes involved in the auxin, abscisic acid (ABA), ethylene, gibberellic acid (GA), and jasmonic acid (JA) signaling pathways, respectively. Notably, genes associated with ABA, including ZjABA3, ZjABA4, ZjABA6, ZjABA7, ZjABA10, ZjABA11, ZjABA15-ZjABA19, ZjABA22-ZjABA25, and ZjABA27-ZjABA33, were downregulated from Stage I to Stage VII. Conversely, the expression of ZjACO in the ethylene signaling pathway was the highest at Stage VII. ZjMYC2-1, a JA signaling pathway gene, was significantly induced at Stage I compared to in the other stages. The genes ZjGID-1 and ZjTF-1, related to GA, exhibited the highest expression levels at Stage VI. Full article

Imidacloprid (IMI), a widely used neonicotinoid insecticide, has raised environmental concerns due to its potential impact on non-target aquatic organisms. This study investigates the effects of IMI exposure on the intestinal immune function of red swamp crayfish (Procambarus clarkii, P. clarkii), focusing on oxidative stress, inflammatory response, and autophagy. The P. clarkii was exposed to different doses of IMI (0, 10.93, 21.86, 43.73, 87.45 μg/L) for 96 h. Our findings reveal that IMI exposure leads to a survival rate of less than 70% when the concentration was 87.45 μg/L at 96 h. Hemolymph LZM and AKP contents were significantly decreased at the medium and high concentrations, and the expressions of hsp70 and nf-κb genes were significantly up-regulated. The expression of the lysozyme gene was significantly down-regulated. Additionally, the activities of SOD, CAT, and GPX were significantly decreased, the contents of MDA were significantly increased, and the gene expressions of CuZnsod, mMnsod, cat, and gpx in the gut were significantly down-regulated after exposure to medium-high IMI. The expression of autophagy-related genes showed that the expressions of beclin1, atg5, atg13, and lc3c genes in the medium- and high-concentration groups were significantly up-regulated. In summary, this study elucidates that medium-high levels of IMI exposure impair intestinal immune function in P. clarkii through mechanisms involving oxidative stress, inflammatory response, and autophagy. Full article

Chromium (Cr) is a toxic heavy metal that affects the food chain and poses a severe threat to food safety. Nonetheless, the N6-methyladenosine (m6A) transcriptomic regulation mechanisms of Cr tolerance genes in rice are not well understood. This study found that rice roots exhibit competitive and synergistic interactions with trace elements under Cr stress. Through a comprehensive transcriptome analysis of m6A methylation profiles under Cr stress, differentially methylated genes (DMGs) closely related to the plasma membrane, oxidoreductase activity, and protein phosphorylation were identified. A significant number of differentially expressed genes (DEGs) associated with heavy metal transporter domains, metalloproteases, metal ion transporters, and other cation transporters were strongly induced by Cr. Additionally, OsHMT9.1 exhibited extensive hypomethylation and up-regulation in Cr-exposed roots and was confirmed to be a regulatory factor for Cr tolerance. Enhanced plant resistance to Cr in oshmt9.1 was accompanied by increased levels of P, K, S, and Ca and decreased levels of Mn and Cu. These results suggest that knocking out OsHMT9.1 can promote Cr detoxification in rice by modulating the balance between Cr and other trace elements. These findings provide new insights into the molecular regulation and stress response of rice under Cr stress through transcriptome m6A methylation patterns. Full article

Heavy metals such as Cu and Cd are important pollutants. Quillay (Quillaja saponaria) is a tree species endemic to Chile that is of worldwide commercial interest due to its saponins. It can grow on contaminated sites. However, the biological mechanisms underlying its defensive responses remain elusive. This study aimed to characterize Quillay plants under Cu and Cd stress and identify mechanisms controlling their interaction with these metals. We subjected six-month-old plants to Cu (75, 150, and 300 μM) and Cd (20, 40, and 80 μM) in hydroponics for a week and assessed growth, metal accumulation, saponin production, and the expression of a suite of stress-induced genes. Those genes are related to phytochelatins (PCS) and metallothioneins (MT), the antioxidant system (GS and GR), and metal transporters (COPT1). The results indicated that both metals were accumulated mainly in roots, with 339.9 and 433.8 mg/kg DW, for Cd and Cu, respectively, exhibiting a metal excluder pattern. Cd increased the length of the principal root. Higher doses of Cd and Cu augmented the saponin content (62.8% and 41.2% compared to control, respectively). The genes GS, GR, and COPT1 modified their transcriptional levels depending on the metal and organ evaluated. These results provide evidence of specific defensive responses of this species against heavy metal stress, which is helpful to guide new research efforts and support the development of strategies for using Quillay for phytoremediation. Full article

Prenatal exposure to metals can influence fetal programming via DNA methylation and has been linked to adverse birth outcomes and long-term consequences. Epigenetic clocks estimate the biological age of a given tissue based on DNA methylation and are potential health biomarkers. This study leveraged the Extremely Low Gestational Age Newborn (ELGAN) study (n = 265) to evaluate associations between umbilical cord tissue concentrations of 11 metals as single exposures as well as mixtures in relation to (1) placental epigenetic gestational age acceleration (eGAA) and the (2) methylation status of the Robust Placental Clock (RPC) CpGs. Linear mixed effect regression models were stratified by infant sex. Both copper (Cu) and manganese (Mn) were significantly associated with a decelerated placental eGA of −0.98 (95% confidence interval (CI): −1.89, −0.07) and −0.90 weeks (95% CI: −1.78, −0.01), respectively, in male infants. Cu and Mn levels were also associated with methylation at RPC CpGs within genes related to processes including energy homeostasis and inflammatory response in placenta. Overall, these findings suggest that prenatal exposures to Cu and Mn impact placental eGAA in a sex-dependent manner in ELGANs, and future work could examine eGAA as a potential mechanism mediating in utero metal exposures and later life consequences. Full article

Brassinosteroids (BRs) are crucial plant hormones that play a significant role in regulating various physiological processes, including micronutrient homeostasis. This review delves into the complex roles of BRs in the uptake, distribution, and utilization of essential micronutrients such as iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and boron (B). BRs influence the expression of key transporter genes responsible for the absorption and internal distribution of these micronutrients. For iron, BRs enhance the expression of genes related to iron reduction and transport, improve root architecture, and strengthen stress tolerance mechanisms. Regarding zinc, BRs regulate the expression of zinc transporters and support root development, thereby optimizing zinc uptake. Manganese homeostasis is managed through the BR-mediated regulation of manganese transporter genes and chlorophyll production, essential for photosynthesis. For copper, BRs influence the expression of copper transporters and maintain copper-dependent enzyme activities crucial for metabolic functions. Finally, BRs contribute to boron homeostasis by regulating its metabolism, which is vital for cell wall integrity and overall plant development. This review synthesizes recent findings on the mechanistic pathways through which BRs affect micronutrient homeostasis and discusses their implications for enhancing plant nutrition and stress resilience. Understanding these interactions offers valuable insights into strategies for improving micronutrient efficiency in crops, which is essential for sustainable agriculture. This comprehensive analysis highlights the significance of BRs in micronutrient management and provides a framework for future research aimed at optimizing nutrient use and boosting plant productivity. Full article