Search Results (6,495)

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has revealed a complex interplay between respiratory and neurological manifestations. This study utilized K18-hACE2 transgenic mice to investigate the morphological, ultrastructural, and transcriptomic changes induced by SARS-CoV-2 infection in both lungs and brain tissues. Histopathological analysis at seven days post-infection revealed significant pulmonary damage characterized by interstitial pneumonia, alveolar septal thickening, with a marked inflammatory infiltrate predominantly consisting of neutrophils and lymphocytes, and an abnormal profile of type II pneumocytes. Concurrently, in the brain, we observed vasculitis, gliosis, and edema, indicating an inflammatory response and vascular compromise that can disturb the blood–brain barrier. In addition, gene expression in lung tissue presented increased CCL2, IL10, and GDDA45D in infected mice and the downregulation of proinflammatory genes. However, in brain tissue, the increased expression of CCL2, CASP1, IL6, IFNB1, and GDDA45G inflammatory genes was observed in infected K18-hACE2 mice. Full article

The safe and precise regulation of therapeutic gene expression remains a major challenge for mammalian synthetic biology and cell-based therapies. Many existing inducible systems rely on non-mammalian regulatory components or ligands with limited clinical compatibility. Designer receptors exclusively activated by designer drugs (DREADDs) offer a human G protein-coupled receptor (GPCR)-based framework for pharmacological control of intracellular signaling, yet their application as clinically relevant gene-regulation platforms remains underexplored. Here, we report a clozapine-responsive gene switch that couples a designer GPCR to signaling-dependent transcriptional control. By linking clozapine-activated receptors to cyclic adenosine monophosphate (cAMP)- or calcium-responsive synthetic promoters, receptor activation is converted into robust transgene expression across a broad dynamic range, with sensitivity to sub-nanomolar to low-nanomolar clozapine concentrations. In vivo, alginate-encapsulated reporter cells implanted in C57BL/6J mice responded to systemic or local clozapine administration with efficient secretion of a reporter protein, achieving robust induction at low daily doses (0.3 mg/kg) following either oral administration or local delivery. Together, these results establish a human GPCR-based clozapine-responsive gene switch that integrates regulation by a clinically used small molecule with modular transcriptional outputs, providing an additional approach for pharmacologically controllable gene expression in mammalian cells and in vivo. Full article

A quartz crystal microbalance-based biosensor for the specific detection of the first transgenic common bean (L.) cultivar (BRS FC401 RMD) with resistance to Bean golden mosaic virus (BGMV) was developed. The immobilization chemistry relies on the strong bond between the thiolated probe and the gold electrode surface. The probe sequence is internal to a region of the BGMV rep gene that was introduced into the common bean genome. The sensor’s analytical performance was determined using synthetic oligonucleotides. Real samples of transgenic and wild-type bean seeds were also tested. Sample pretreatment consisted only of enzymatic fragmentation, followed by a thermal denaturation step combined with blocking oligonucleotides. Different biosensor regeneration approaches were studied. Immobilization showed good reproducibility (CV% of 5.8%). The biosensor proved specific for both synthetic oligonucleotides and non-amplified genomic DNA. A linear detection range of 0–1.4 ng/µL was observed, with a detection limit of 0.18 ng/µL. Three sequential detections were performed without loss of surface activity. The results demonstrate the biosensor’s potential for direct, real-time, label-free detection of DNA samples for field screening of transgenic common bean cultivars. Full article

Cunninghamia lanceolata (C. lanceolata), a pivotal economic timber species in southern China, faces increasing threats from global warming and heat stress. Due to limited knowledge regarding its stress response mechanisms, uncovering the molecular basis of heat tolerance is crucial for breeding resilient varieties. Therefore, the objective of this study was to elucidate the physiological and molecular mechanisms of C. lanceolata in response to heat stress. In this study, we performed a time-series transcriptomic analysis on leaves of C. lanceolata ‘6421’ seedlings exposed to heat stress (39 °C) for 0, 1, 4, 8, 12, and 16 h. A total of 1130 differentially expressed genes (DEGs) were identified, with functions primarily enriched in signal transduction, protein folding, and the MAPK and NF-kappa B signaling pathways. Weighted gene co-expression network analysis (WGCNA) revealed a complex regulatory network, identifying ClHsf8 as a central hub transcription factor. To validate its function, ClHsf8 was cloned and overexpressed in tobacco (Nicotiana benthamiana). Under heat stress conditions, transgenic plants exhibited enhanced thermotolerance compared to wild-type controls, characterized by significantly higher activities of antioxidant enzymes (SOD, POD, and CAT) and reduced accumulation of MDA and H₂O₂. Our findings elucidate the molecular regulatory mechanisms of C. lanceolata in response to high temperatures and demonstrate the functional role of ClHsf8 in conferring heat tolerance, providing a theoretical foundation for the genetic improvement of heat-resilient cultivars. Full article

Genetically modified (GM) plants have been commercially grown for 30 years, and their acceptance depends on a thorough risk assessment. Environmental Risk Assessment (ERA) evaluates potential impacts of releasing GM plants into the environment, whether through cultivation or import for food, feed, and processing. A key component is assessing potential gene flow to crop wild relatives or non-GM crops. For gene flow to significantly affect the environment, transferred genes must provide a selective advantage. Since most GM plants are engineered for herbicide tolerance, insect resistance, or stacked traits, evaluating such advantages is relatively straightforward. New genomic techniques (NGTs) can generate plants with a wider range of traits, including tolerance to biotic and abiotic stress. Although still considered GM in the EU, their genomic changes can complicate detection, identification, and ERA, especially when such traits may offer advantages under stress conditions. This scoping review focuses on gene flow in two crops: oilseed rape (canola) (Brassica napus L.) and potato (Solanum tuberosum L.). In canola, transgene movement can increase weediness, fitness, herbicide resistance, or genetic diversity in feral or related populations. Gene flow in potato is less studied, with concerns centered on contamination risks in the Andean diversity center. Limited data exist for NGT plants, though many are expected to resemble conventionally bred varieties, suggesting comparable environmental impacts. Full article

Exosomes (EXs) mediate intercellular communication in the tissue microenvironment. We previously demonstrated that endothelial progenitor cell-derived exosomes (EPC-EXs) from exercised mice protect neurons and cerebral endothelial cells from hypoxia- and hypertension- induced injury ex vivo, suggesting their therapeutic potential in hypertensive ischemic injury. Here, we investigated whether exercise-conditioned EPC-EXs (ET-EPC-EXs) confer protection against acute ischemic injury. Hypertensive transgenic mice were divided into donor and recipient groups. Donor mice underwent treadmill exercise to generate ET-EPC-EXs. Recipient mice was subjected to middle cerebral artery occlusion and received ET-EPC-EXs via tail vein injection (2 × 10⁸/100 μL saline) two hours after stroke onset. Cerebral blood flow (CBF) was assessed, and brains were collected on day two for histological and molecular analyses. Our data showed that ET-EPC-EXs were robustly taken up by cerebral cells, predominantly in the penumbra in the ipsilateral hemisphere. ET-EPC-EXs reduced cell death and microglia activation and restored tight-junction proteins. Moreover, ET-EPC-EX treatment preserved CBF and improved sensorimotor function on day two post-stroke. Mechanistically, ET-EPC-EXs suppressed p38 activation, accompanied by reduced matrix metalloproteinase-3 and cytochrome c levels in the ipsilateral brain. Collectively, these findings demonstrate that EPC-EXs from exercise mice improve sensorimotor functions and confer protection in hypertensive ischemic brain injury, likely through attenuation of neuroinflammation and preservation of vascular integrity via modulation of the p38 signaling. Full article

Pinoresinol diglucoside (PDG), one of the major lignans isolated from E. ulmoides Oliver bark, has various pharmacological functions, including antihypertension and prevention of osteoporosis. However, the glycosyltransferase-encoding gene (GT) involved in regulating the glycosylation of pinoresinol to form PDG has not been reported in E. ulmoides. In this study, we screened and cloned the EuGT8 gene from E. ulmoides based on our transcriptome data. The expression pattern of the EuGT8 gene exhibited a strong positive correlation with dynamic changes in the PDG contents in three different organs of E. ulmoides. The expression level of the EuGT8 gene and PDG content were significantly decreased in asODN-EuGT8-treated shoot tips in comparison with the control group. Prokaryotic expression of the EuGT8 gene revealed that the purified EuGT8 protein could catalyze the conversion of pinoresinol into PDG. In addition, we performed transcriptional and metabolomic analyses to compare the differences between transgenic Arabidopsis and WT plants. A total of 1799 DEGs and 294 DEMs were identified in transgenic and WT plants. KEGG enrichment analysis showed that the DEGs were mainly enriched in phenylpropanoid biosynthesis, secondary metabolite biosynthesis, and starch/sucrose metabolism pathways. The DEMs were mainly enriched in ABC transporters, aminoacyl-tRNA biosynthesis, biosynthesis of amino acids, phenylpropanoid biosynthesis, and flavone and flavonol biosynthesis pathways. Correlation analysis between DEGs and DEMs identified a total of 231 DEGs associated with 38 DEMs, which were mainly distributed in multiple metabolic pathways. This finding provides both theoretical insights and genetic resources for breeding high-PDG E. ulmoides varieties, facilitating marker-assisted selection (MAS) and promoting sustainable E. ulmoides production in Guizhou. Full article

Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterized by progressive synaptic dysfunction, axonal pathology, and cognitive decline, with the hippocampal circuits showing particular vulnerability during disease progression. However, early-life nutritional interventions may influence long-term synaptic resilience. In this study, we investigated the long-term effects of prenatal and lactational supplementation with choline, UMP, and fish oil in the 5XFAD mouse model. To this end, hippocampal synaptic and axonal pathology was assessed at 3, 6, and 9 months using Western blotting and immunofluorescence to measure synaptophysin, PSD-95, and neurofilament medium chain (NF-M), alongside a multidimensional behavioral battery that evaluated cognitive, affective, motor, and sensory outcomes. Results showed that early-life supplementation did not significantly improve the learning performance decline, increase nociception, or reverse changes in anxiety behavior in transgenic mice. However, it attenuated synaptic decline in transgenic animals by partially preserving synaptophysin and PSD-95 levels and reducing NF-M elevations. These molecular effects were accompanied by selective behavioral modulation, including preserved learning dynamics, altered anxiety-like behavior, and delayed nociceptive hypersensitivity, while late-stage motor impairments remained largely unaffected. Overall, prenatal and lactational supplementation produced modest, age-dependent effects on synaptic markers and partially prevented neurodegenerative progression in the 5XFAD model. Full article

Stevia rebaudiana Bertoni is a strategically important perennial crop because it is the main botanical source of steviol glycosides, a group of high-intensity, non-caloric sweeteners increasingly demanded by the global food and beverage industry. Despite the rapid expansion of stevia cultivation, commercial production remains strongly dependent on a narrow genetic base, particularly on clonally propagated cultivars such as ‘Morita II’, which has long served as the industrial benchmark because of its favourable rebaudioside A profile and processing consistency. This dependence has raised concerns about limited adaptive capacity, genetic erosion and restricted long-term breeding progress. In this review, we provide an integrated and critical synthesis of current knowledge on the genetic diversity of S. rebaudiana, the biosynthetic and regulatory architecture of steviol glycosides, and the conventional and emerging strategies available for crop improvement. Unlike previous reviews, this article explicitly connects domestication-driven genetic bottlenecks, wild germplasm mobilisation, metabolic pathway regulation, advanced analytical phenotyping and precision breeding into a single systems-oriented framework. We examine the roles of wild germplasm, somaclonal variation, polyploidy, molecular markers, omics-assisted approaches and transgene-free genome editing as complementary tools to broaden the stevia breeding base while preserving industrial quality standards. We finally propose an integrative roadmap for the sustainable genetic improvement of stevia, positioning ‘Morita II’ not as an endpoint, but as a benchmark within a broader diversification strategy. Full article

DREB (Dehydration-Responsive Element-Binding Protein) transcription factors are a subfamily of the AP2/ERF transcription factor family and play a crucial role in the regulation of plant responses to abiotic stress. In this study, we successfully cloned the IbDREB1d gene from the leafy sweet potato cultivar Fucaishu18. The open reading frame (ORF) of the IbDREB1d gene comprises 792 base pairs and encodes a protein consisting of 263 amino acids. Protein sequence analysis indicates that IbDREB1d is characterized by acidic, hydrophilic, and unstable properties, with its closest phylogenetic relationships to Ipomoea trifida and Ipomoea triloba. Quantitative real-time PCR (RT-qPCR) analysis revealed that IbDREB1d is expressed in the roots, stems, and leaves of sweet potato, with increased expression under low temperature, hydrogen peroxide (H₂O₂), and drought conditions. Overexpression of IbDREB1d in sweet potato resulted in transgenic plants exhibiting dwarfism, shortened internode lengths, smaller leaf size, and microscopic evidence of impaired vascular tissue development. Hormonal analysis indicated significant reductions in the levels of indole-3-acetic acid, indole-3-butyric acid, salicylic acid, and zeatin in these transgenic plants. These decreases may explain the observed phenotypic changes, such as inhibited growth and reduced leaf size. This study provides novel theoretical insights into the role of IbDREB1d in stress-responsive expression and modulating plant growth in sweet potato. 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

Neurodegenerative diseases such as Alzheimer’s (AD) and Huntington’s (HD) remain major therapeutic challenges due to limited treatment efficacy. Imidazoline I2 receptor (I2-IR) ligands have recently emerged as promising neuroprotective agents, with reported roles in modulating oxidative stress, neuroinflammation, and protein aggregation. This study evaluates the therapeutic potential of several I2-IR ligands, including Idazoxan, CR4056, and novel compounds, using Caenorhabditis elegans (C. elegans) models of AD and HD. Transgenic strains CL2006 (expressing human Aβ1-42) and EAK103 (expressing Ht513) were employed to assess locomotor activity, oxidative stress tolerance, Aβ and Ht aggregation, and sod-1 gene expression. Several ligands significantly improved movement, reduced Aβ and Ht aggregates, and enhanced antioxidant gene expression, particularly Idazoxan, LSL42, and PIP01. Notably, some compounds exhibited prooxidant effects, highlighting the utility of C. elegans for early in vivo toxicity screening. Importantly, this study provides the first in vivo evidence of the efficacy of I2-IR ligands in HD models and reinforces their potential as therapeutic candidates for HD. Overall, these findings suggest a potential role for modulation of I2-IR-related pathways in neurodegeneration and support the utility of C. elegans as a rapid, cost-effective platform for preclinical drug evaluation. Full article

Puccinia graminis f. sp. tritici (Pgt) is responsible for stem rust in wheat, a disease with worldwide occurrence. Ethylene response factors (ERFs), a group of transcription factors (TFs) responsive to ethylene, are essential for managing stress signaling under biotic and abiotic challenges. However, our understanding of ERF TFs’ function in wheat (Triticum aestivum L.) resistance against the obligate biotrophic Puccinia graminis f. sp. tritici remains limited. In this work, we report our findings of the TaERF109 gene, which is transcriptionally up-regulated by ethylene or Pgt infection. TaERF109 is localized in the nucleus of rice protoplasts. Results obtained using the yeast one-hybrid (Y1H) assay support the conclusion that TaERF109 interacts with the AGCCGCC sequence (GCC-box). Transient knockdown of TaERF109 via virus-induced gene silencing (VIGS) increased wheat susceptibility to Pgt, accompanied by the down-regulation of three pathogenesis-related (PR) genes, TaPR1, TaPR2, and TaPR10, as confirmed via real-time quantitative PCR. In contrast, the Agrobacterium-mediated overexpression of TaERF109 potentiated resistance of transgenic wheat against Pgt. Overall, these results expand the current understanding of the TaERF109 gene’s function in wheat resistance to Pgt. Full article

Granule-bound starch synthase (GBSS) is primarily recognized for its role in amylose production and starch granule formation in plant plastids. While its biochemical function in storage organs has been well documented, its broader contribution to plant growth and stress adaptation remains less defined. To explore these aspects, the maize gene ZmGBSS1 was ectopically expressed in Arabidopsis thaliana and its physiological effects were examined. Subcellular localization assays confirmed that ZmGBSS1 is specifically localized to chloroplasts. Phenotypic analysis of transgenic lines revealed that overexpression of ZmGBSS1 significantly altered early seedling development, promoted root elongation, and accelerated flowering, with flowering occurring approximately four days earlier than in wild-type plants. Changes in development were accompanied by increased starch accumulation, elevated amylose levels, and a higher abundance of enlarged starch granules within chloroplasts. Under drought and PEG-induced osmotic stress, transgenic plants maintained improved growth performance and recovery capacity, together with greater proline accumulation and chlorophyll retention. These physiological advantages coincided with more rapid starch utilization and clear rises in transcripts for proline synthesis enzymes (AtP5CS1, AtP5CS2) and starch-degrading proteins (AtBAM1, AtBAM3, AtDPE1). Collectively, these findings suggest that ZmGBSS1 not only regulates starch biosynthesis but also plays a crucial role in coordinating plant development and drought stress responses, highlighting its potential for improving stress tolerance through metabolic regulation. Full article

Salt stress severely restricts grape (Vitis vinifera L.) production. Serine/arginine-rich (SR) proteins, as a class of RNA-binding proteins, play important roles in plant growth, development and stress responses. However, the function and regulatory mechanism of VvSR34a in grape salt tolerance remain unclear. In this study, grape callus and cutting seedlings were used as materials to explore the role and molecular mechanism of VvSR34a in grape salt stress response. The results showed that, under 100 mM NaCl treatment, the relative level of VvSR34a in grape callus exhibited a ‘first increase and then decrease’ pattern, reaching a peak at 2 h, and the gene was localized in the nucleus. Transgenic experiments confirmed that the overexpression of VvSR34a significantly enhanced salt tolerance in grape callus and cuttings, as evidenced by better growth status, higher chlorophyll content and root activity, as well as lower electrolyte leakage and malondialdehyde (MDA) content under salt stress. In contrast, the silencing of VvSR34a significantly increased salt sensitivity in grapes. Y2H and LCI assays verified that VvSR34a physically interacts with VvCOP9. VvCOP9 may play a negative regulatory role in the salt stress response of the grapevine, and through the loss of the high salt-tolerant phenotype in the VvSR34a/VvCOP9-RNAi lines, it demonstrated that VvCOP9 is genetically upstream of VvSR34a. Furthermore, the ubiquitination and degradation assay demonstrated that VvCOP9 can significantly promote the degradation of VvSR34a. RNA-seq analysis showed that a total of 2834 differentially expressed genes and 202 alternative splicing events were detected in VvSR34a overexpression lines. These differentially expressed genes were significantly enriched in ATPase activity, redox and hormone signaling pathways. This study demonstrates that VvSR34a positively regulates salt tolerance in grapes, providing an important theoretical basis for molecular breeding of salt-tolerant grapevines. Full article