Search Results (12,901)

The sycamore lace bug, Corythucha ciliata, a globally invasive pest that damages Platanus spp., harbors a bacterial microbiome that may help it adapt to different geographical environments. However, the geographical differentiation patterns of its bacterial community and the underlying driving mechanisms remain unclear. In this study, we standardized rearing of three C. ciliata populations (collected from Beijing, Lianyungang, and Nanjing) for three generations to reduce immediate environmental interference, then analyzed their bacterial communities via 16S rRNA gene amplicon sequencing. The principal coordinate analysis revealed a significant separation of the bacterial community in the Nanjing population, while the Beijing and Lianyungang populations were more similar. Bacterial alpha diversity followed the gradient of “Nanjing > Lianyungang > Beijing”, with the Nanjing population exhibiting significantly higher species richness and evenness than the Beijing population. All three populations shared core bacterial taxa (e.g., phyla Proteobacteria, Bacteroidota; genera Cardinium, Serratia), but their relative abundances differed significantly: Cardinium dominated the Beijing population (50.1%), Serratia dominated the Lianyungang population (45.86%), and the Nanjing population harbored unique dominant genera such as Sphingomonas. For the three target populations, monthly average temperature and wind speed were positively correlated with bacterial diversity, while latitude was negatively correlated (Pearson correlation coefficient: 0.6564 < |r| < 0.7010, p < 0.05). Core bacterial functions (e.g., substance transport) were conserved across populations, whereas differential functions (e.g., detoxification, lipid metabolism) were linked to geographical adaptation. This study confirms the climate-driven geographical differentiation of the C. ciliata bacterial community provides insights into the “insect–microbiome” interactive invasion mechanism that is present here. Full article

Rotavirus alphagastroenteritidis (rotavirus) infects a broad range of hosts, including humans and various animal species. Its genome comprises 11 segments of double-stranded RNA, making it highly prone to genetic diversity through gene reassortment. Although rotavirus strains are typically host-specific, novel human strains with global impact often originate from interspecies transmission of animal rotaviruses. This review explores the critical role of interspecies transmission coupled with genetic reassortment in rotavirus adaptation to humans, contextualizing key studies and methodological advances. Central to this progress was the development of tools to analyse entire genomes and distinguish homologous from heterologous strains. We trace the evolution from RNA-RNA hybridisation to whole-genome sequencing, which underpins genotype constellation and sub-genotype phylogeny. A decade-long surveillance of the bovine-like G8 rotavirus in Vietnam offers a compelling model: for an animal rotavirus to become a successful human pathogen, it must replace its animal-derived genes with human-derived counterparts through reassortment. Retaining the animal-origin G8 VP7 gene is enabled by acquiring a compatible human VP4 gene (specifically P[8]) and DS-1-like backbone genes. Building on this model of reassortment-driven adaptation, our investigation into the unusual G1P[6] strain AU19, of wholly porcine origin, supports the hypothesis that the predominant human G1 rotavirus also evolved from a successful interspecies transmission event. Phylogenetic analysis suggests the ancestral human G1 gene emerged from a porcine rotavirus between 1915 and 1948, later reassorting with human strains to acquire Wa-like backbone genes, ultimately becoming a stable and dominant part of the human rotavirus population. In conclusion, genetic reassortment is a key mechanism transforming sporadic zoonotic events into sustained human-pathogens, although other factors remain to be fully defined. We conclude by highlighting key areas for further research. Full article

Transcription factors (TFs) orchestrate plant growth and development, yet the functional landscape of many TF gene families remains incomplete. Here, we systematically characterize OsWRKY7, an unannotated WRKY TF in rice. Phylogenomic analyses revealed that the WRKY7 subfamily originated in basal angiosperms and evolved under strong purifying selection. We demonstrate OsWRKY7 functions as a WRKY transcriptional activator, with its activity uniquely encoded within the N-terminal domain—a distinctive mechanism among WRKY proteins. The promoter is enriched with cis-elements responsive to hormone and stress signaling, and the gene shows predominant expression in seeds. Strikingly, haplotype analysis revealed exceptionally low genetic diversity at the OsWRKY7 locus, suggesting evolutionary constraint or a recent selective sweep. Our findings establish OsWRKY7 as a conserved regulator with unique molecular features, specifically the WRKY domain, providing a strategic target for both fundamental research and crop improvement. Full article

Microplastics derived from biodegradable PBAT film, widely used in agriculture, pose ecological and biological hazards. This study explores how Trichoderma harzianum T4 mitigates this microplastic-induced stress in Nicotiana benthamiana. Using five experimental setup-control (CK), low/high-dose aged microplastics (MP80/MP320), and their co-treatments with T. harzianum T4 (MP80+T4/MP320+T4), multi-omics analyses reveal the microplastic stress-alleviating mechanisms of T. harzianum T4. Aged microplastics significantly inhibit plant growth, promote reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation, and disrupt metabolic homeostasis. Conversely, T. harzianum T4 activates the plant antioxidant defense system, reducing ROS/MDA levels and upregulating superoxide dismutase (SOD)/peroxidase (POD) activities, and promotes biomass. Transcriptomic analysis shows T. harzianum T4 reverses gene expression patterns disrupted by microplastics, particularly in DNA replication and pentose–glucuronic acid pathways. Metagenomic sequencing indicates T. harzianum T4 restores soil microbial diversity, increases the abundance of Bacteroidota and Myxococcota, downregulates antibiotic resistance genes (e.g., tetA5, MDR), and upregulates carbohydrate-active enzymes (CAZys), thereby enhancing carbon metabolism. In conclusion, T. harzianum T4 alleviates microplastic stress through a tripartite mechanism: activating plant stress-response gene networks, reshaping soil microbial communities, and modulating functional gene expression, offering a promising bioremediation strategy. Full article

Enzymes are indispensable in fields such as biotechnology, medicine, and industrial manufacturing due to their high catalytic specificity and efficiency under mild conditions. However, their natural versions often suffer from limitations, including low activity toward non-natural substrates, poor stability under extreme conditions, and narrow substrate spectra. Directed evolution, a key protein engineering strategy that optimizes protein function via genetic diversity introduction and directed selection, has become the primary solution to these limitations. Among its mature methodological systems, in vivo evolution platforms (advanced by synthetic biology) are particularly efficient, as they integrate in-cell mutation, translation, selection, and replication into an automated process, significantly improving experimental efficiency. This review will focus on two core strategies that enhance these platforms: in vivo targeted gene hypermutation and heterologous polymerase-mediated targeted hypermutation. These techniques enable the rapid optimization of enzymes to acquire novel functions, as well as the comprehensive engineering of microbial strains to enhance their performance and stress tolerance. Analyzing these strategies provides a robust technical framework for enzyme engineering and promises to drive future innovations across multiple fields. Full article

Background: Dihydromyricetin (DHM), a natural dihydroflavonol, exhibits diverse pharmacological properties, including anti-inflammatory, antioxidant, and anti-tumor effects. However, its potential mechanism of action in the individualized therapy of hepatocellular carcinoma (HCC) remains unclear. Methods: Potential therapeutic targets of DHM were identified using the Swiss Target Prediction database. The overlap between these targets and differentially expressed genes in HCC was analyzed to determine therapeutic targets. A prognostic model was constructed based on these genes, and patients were stratified into high- and low-risk groups. The associations between risk scores, clinical pathological characteristics, and overall survival were analyzed using Cox regression and Kaplan–Meier survival curves. The relationships between risk score and immune cell infiltration, immunosuppressive factors, and anticancer drug susceptibility were evaluated. Results: A three-gene prognostic model was established, comprising DTYMK, MAPT, and UCK2, designated as DHM-target genes (DHMGs). Patients in the high-risk group had significantly shorter overall survival than those in the low-risk group (p < 0.001; HR [95% CI] = 4.953 [2.544, 9.645]). Higher risk scores were correlated with more advanced tumor stages and grades. Comprehensive analysis of the tumor immune microenvironment revealed that high-risk patients exhibited significantly elevated TIDE scores, increased Treg cell infiltration, and markedly reduced stromal scores. Conclusions: This study developed a prognostic model based on the potential target genes of DHM in HCC. This model effectively stratifies HCC patients, identifying a high-risk subgroup characterized by an immunosuppressive microenvironment. These findings provide a theoretical foundation for exploring DHM as a promising natural adjuvant for cancer immunotherapy. Full article

Quinoa (Chenopodium quinoa Willd.), an Andean crop with exceptional nutritional value, thrives in ecosystems exposed to intense ultraviolet-B (UV-B) radiation; yet the molecular mechanisms underlying its photoreception remain largely unknown. The UV Resistance locus 8 (UVR8) protein, a member of the Regulator of Chromosome Condensation 1 (RCC1) family, is the primary UV-B photoreceptor in plants. Here, we report the first in silico characterization of the RCC1 gene family in C. quinoa, aimed at identifying and structurally analyzing UVR8 homologs. Genomic analysis uncovered 40 CqRCC1 genes, exhibiting extensive structural diversity. Phylogenetic reconstruction identified two proteins, CqRCC1_20 and CqRCC1_23, as the closest homologs of AtUVR8 from Arabidopsis thaliana. Homology modeling revealed that CqRCC1_20 maintains the canonical seven-bladed β-propeller architecture of UVR8, whereas CqRCC1_23 carries a deletion leading to a six-bladed structure. Both isoforms retain the critical tryptophan residues (W233, W285, W337) and the C-terminal Valine-Proline (VP) motif required for photoperception and Constitutive Photomorphogenic 1 (COP1) interaction. Notably, the CqRCC1_23 model predicts fewer hydrogen bonds at the dimer interface and structural alterations at key regulatory interaction sites. Collectively, these results indicate that quinoa harbors functionally conserved UVR8 isoforms with structural divergence, such as CqRCC1_23, which may influence photoreceptor stability and enable a sustained UV-B response, potentially conferring an adaptive advantage in high-radiation environments. Full article

Toll-like receptors (TLRs) are central to pathogen recognition in teleost innate immunity. In this study, we surveyed 41 genomes from four representative teleost orders (i.e., Cypriniformes, Siluriformes, Perciformes, and Pleuronectiformes) for 15 TLR genes (TLR1–9, 12, 13, 18, 20–22) revealed a conserved core (TLR2/3/7 in nearly all examined species) alongside lineage-specific losses (TLR4/9/18/20/21/22), indicating both strong conservation and dynamic diversification of the TLR repertoire. We further identified and characterized 12 TLR genes in economically important darkbarbel catfish (Pelteobagrus vachellii). Corresponding cDNAs span 2089–4456 bp and encode proteins of 789–1,087 aa, with canonical extracellular LRR arrays and C-terminal TIR domains but notable “non-classical” features (such as absence of signal peptides in TLR1/13; no transmembrane segment in TLR7; multiple transmembranes in TLR3/8/13/18/22), suggesting subcellular and functional heterogeneity of various TLR genes. Subsequent gene-structure comparisons uncovered gene-specific exon–intron organizations and variable UTR lengths, implicating differential post-transcriptional regulation. Predicted 3D structures retain the traditional hallmark LRR horseshoe fold with subtle variations potentially tuning ligand specificity. Genomic synteny with Pseudobagrus ussuriensi and Pangasianodon hypophthalmus reveals conserved chromosomal organization, and phylogeny construction resolves each TLR subtype into well-supported monophyletic clades, which underscore evolutionary stability. Functionally, exogenous Aeromonas hydrophila challenge triggered rapid, tissue-dependent TLR up-regulation in the kidney, liver, and especially gill (with some transcripts > 1000-fold), highlighting coordinated mucosal and systemic surveillance in darkbarbel catfish. Taken together, these valuable data provide a comprehensive framework for the structural, evolutionary, and inducible expression landscape of catfish TLRs and establish a foundation for in-depth studies on antibacterial immunity in diverse teleost species. Full article

Lichens are complex symbiotic systems known for synthesizing diverse secondary metabolites with documented antimicrobial, antioxidant, and antiproliferative activities. The present study focused on Pseudevernia furfuracea, a species widely distributed across Moroccan habitats. Two hydrodistillation-derived extracts (HE1 and HE2) were analyzed through ultra-high-Performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) to characterize their metabolite composition, and their effects were evaluated on Jurkat cells, a representative human cell line of the immune system. As the results of the characterization, the main compounds identified were Caprolactam, N,N-Diethylaniline, Erucamide, and 4-Isopropylaniline. Cytotoxicity assessment revealed that both HE1 and HE2 decreased the viability of Jurkat cells in a concentration-dependent manner. The mean effective concentrations (EC₅₀) after 24 h of treatment were 53.79 ± 2.92 µg/mL for HE1 and 59.76 ± 2.01 µg/mL for HE2. Cell death mechanisms were further examined by flow cytometry, revealing that apoptosis predominated after 24 h of treatment, progressing mainly to late apoptotic stages after 48 h. In parallel, the expression levels of key cytokine genes, including IL-2, TNF-α, and IFN-γ, were quantified at the mRNA level to evaluate potential immunomodulatory effects. Up-regulation was observed in IL-2 after exposure to both extracts for 24 and 48 h, and in the case of IFN-γ after exposure to HE2 for 24 h; in contrast, HE1 and HE2 produced down-regulation in TNF-α at 24 h. These findings suggest that HE1 and HE2 have immunomodulatory activity in Jurkat cells. Further investigations are needed to elucidate the underlying mechanisms and to clarify how HE1 and HE2 influence immune responses in human systems. Full article

Lysosomal storage disorders (LSDs) represent a diverse group of inherited metabolic diseases in which impaired lysosomal function leads to progressive accumulation of undegraded substrates and widespread cellular dysfunction. Although traditionally classified according to the type of stored macromolecule, this substrate-based approach often fails to reflect the underlying molecular mechanisms. Recent advances in genetics and cell biology have prompted a shift toward functional classifications that group disorders by the lysosomal pathway disrupted—namely, enzymatic hydrolytic defects, transporter-related defects, biogenesis and signaling defects, and cross-organelle interaction abnormalities. This framework better captures disease complexity and provides a translational roadmap for precision medicine. The neurological system, with its high metabolic demands and vulnerability to impaired clearance mechanisms, is particularly affected, leading to clinical phenotypes ranging from developmental delay to severe neurodegeneration. Genomic technologies and multi-omics platforms have facilitated earlier diagnoses, revealed atypical variants, and informed the development of tailored therapies such as enzyme replacement, substrate reduction, chaperone-based approaches, and gene therapy. The current review proposes a cellular-pathway-oriented framework for classifying LSDs with neurological features and underscores how such an approach can assist in the development of personalized therapeutic strategies. Full article

Toxin–antitoxin (TA) modules represent sophisticated regulatory networks that have evolved from simple plasmid maintenance factors into multifunctional genetic modules orchestrating bacterial stress responses, pathogenesis, and ecological adaptation. This review highlights a compelling correlation between the abundance of toxin–antitoxin (TA) modules and bacterial pathogenicity, as exemplified by Mycobacterium tuberculosis (M.tb), which encodes 118 TA loci—significantly more than the fewer than 10 found in closely related saprophytic species. The clinical significance of TA modules extends beyond traditional stress response roles to encompass antimicrobial persistence, where systems like VapBC and MazEF facilitate dormant subpopulations that survive antibiotic therapy while maintaining chronic infections. Recent discoveries have revealed TA modules as sophisticated bacterial defense mechanisms against bacteriophage infection, with DarTG and ToxIN systems representing novel antiviral immunity components that complement CRISPR-Cas and restriction–modification systems. The immunomodulatory capacity of TA modules demonstrates their role in host–pathogen interactions, where systems such as VapC12 in M.tb promote macrophage polarization toward permissive M2 phenotypes while inducing anti-inflammatory cytokine production. Large-scale genomic analyses reveal that TA modules function as drivers of horizontal gene transfer networks, with their signatures enabling accurate prediction of plasmid community membership and serving as determinants of microbial community structure. The biotechnological applications of TA modules have expanded to include genetic circuit stabilization, biocontainment device construction, and multi-species microbial community engineering, while therapeutic strategies focus on developing multi-target inhibitors against conserved TA protein families as promising approaches for combating drug-resistant bacterial infections. The evolutionary conservation of TA modules across diverse bacterial lineages underscores their fundamental importance as central organizing principles in bacterial adaptation strategies, where their multifunctional nature reflects complex selective pressures operating across environmental niches and host-associated ecosystems. This review provides an integrated perspective on TA modules as dynamic regulatory elements that support bacterial persistence, immune evasion, and ecological versatility, establishing them as genetic elements with truly “many faces and functions” in prokaryotic biology. Full article

Background/Objectives: Protein-calorie malnutrition (PCM) is common among patients with inflammatory bowel disease (IBD). However, the relationship between PCM and the gut microbiota in patients with IBD remains unclear. This study aimed to investigate the association between PCM and the colonic mucosal microbiota in patients with IBD. Methods: Colonic mucosal samples were obtained from 24 IBD patients with PCM and 24 IBD type-matched patients without PCM. PCM was defined as a body mass index (BMI) < 18.5 kg/m² and/or weight loss of ≥10% within the preceding 6 months. The full-length bacterial 16S ribosomal RNA gene (V1–V9) was sequenced using the PacBio Sequel IIe. Alpha and beta diversity and species-level differential abundance were analyzed, adjusting for age, sex, BMI, and disease type. Results: Among 48 patients (36 Crohn’s disease and 12 ulcerative colitis), diversity indices (Chao1, p = 0.474; Shannon, p = 0.931) and overall composition (Bray–Curtis, p = 0.719) did not differ by PCM status, although microbial composition was associated with age (p = 0.011) and biopsy-site inflammation (p = 0.001). PCM was associated with 12 differentially abundant taxa, including enrichment of Intestinibacter bartlettii and depletion of Bifidobacterium longum, Sphingomonas leidyi, and Clostridium innocuum, along with changes in several previously unclassified species. Conclusions: IBD patients with PCM exhibited shifts in the colonic mucosal microbiota including reduction in Bifidobacterium longum, a well-known probiotic. Further investigations into the role of the microbiota in PCM in IBD patients and the potential beneficial effects of probiotics are warranted. Full article

Polyextremophilic microbial communities of Baikal Rift Zone hot springs have been studied fragmentarily, and these studies have typically focused on either phototrophic microbial mats or on the whole microbial community from one or a few sites. In our work, we conducted the first large-scale screening of microbial communities from seven hot spring groups in the Baikal Rift Zone, using metabarcoding of the V3-V4 regions of the 16S rRNA gene. Analysis of alpha and beta diversity, as well as co-occurrence network analysis, revealed that the microbial diversity of the studied springs is highly dependent on temperature values. This approach allowed classifying microbial communities into four distinct groups, characterized by significantly different taxa representing the key functional roles of primary producers, heterotrophic consumers, and terminal destructors of organic matter. Sulfate-reducing bacteria constituted a major metabolic group driving the final stage of organic matter mineralization. Moreover, the presence of alkalithermophilic dissimilatory iron reducers, whose existence was debatable, was proved in the studied samples by cultural methods. The phylotypes that gained an advantage on selective media with synthesized ferrihydrite and hydrogen or acetate added as an electron donor belonged to the genus Parvivirga of the order Anaerosomatales and several unknown representatives of the phylum Bacillota. Full article

Watermelon chlorotic stunt virus (WmCSV), a bipartite begomovirus, poses a severe and expanding threat to global cucurbit and watermelon production, driving an urgent need to unravel its genetic diversity indices and evolutionary complexities. To elucidate its evolutionary history, this study investigated the genetic diversity, evolutionary dynamics, and global dispersal of its genomic components, DNA-A (WmA) and DNA-B (WmB). The analyses uncovered striking contrasts between the components. WmB exhibited markedly greater genetic diversity (π = 0.0508 vs. 0.0119 for WmA), a slightly faster evolutionary rate (1.26 × 10⁻⁴ vs. 1.44 × 10⁻³ substitutions/site/year), and a far more complex recombination profile, with 34 events detected compared to only one in WmA. The abundance of recombination breakpoints in WmB underscores its central role in shaping genomic variability and adaptive potential. Phylogenetic analyses of both components unveil eight robustly supported clades per segment, predominantly shaped by geographical boundaries, hinting at localized evolutionary trajectories with constrained long-distance gene flow, with the exception of Oman. Bayesian time-scaled phylogenies and phylogeographic reconstructions further illuminate distinct dissemination pathways, suggesting an intriguing origin, with WmA likely emerging from the United States and WmB tracing back to Saudi Arabia, while the Middle East emerges as a dynamic epicenter for regional spread and subsequent incursions into the Americas. Together, these findings reveal contrasting evolutionary forces driving WmCSV diversification and provide critical insights into its origins and ongoing global emergence. Full article

Cronobacter sakazakii is a foodborne pathogen of major concern due to its link with severe neonatal infections through powdered infant formula (PIF). However, its genomic epidemiology in Bangladesh remains uncharacterized. We report the first whole-genome analysis of three isolates from PIF. Two isolates (S41_PIFM and S44_RUTF) belonged to ST83, a lineage repeatedly associated with neonatal meningitis, septicemia, and persistence in PIF production environments, while the third (S43_TF) represented ST789, a recently described and rare lineage of unknown pathogenic potential. Pan-genome and comparative analyses identified 39 virulence determinants, 19 antimicrobial-resistance genes, and diverse mobile genetic elements. ST83 isolates harbored plasmid replicons IncFII(pCTU2) and pESA2, while the ST789 isolate carried insertion sequence ISKpn34, indicating horizontal gene transfer potential. All strains encoded I-E CRISPR-Cas systems. The detection of globally recognized high-risk ST83 clones alongside the novel ST789 lineage highlights emerging public health risks. This study provides the first genomic insights into C. sakazakii in Bangladesh and underscores the urgent need for genomic surveillance and strengthened food safety monitoring to protect infant health in low- and middle-income countries. Full article