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PubMed2026

High-affinity, structure-validated and selective macrocyclic peptide tools for chemical biology studies of Huntingtin.

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by a Cytosine-Adenosine-Guanine (CAG) repeat expansion in the Huntingtin (HTT) gene, with no disease-modifying therapies currently available. The precise molecular function of the HTT protein is unclear, and the lack of selective chemical tools has limited functional studies. We have identified and characterized macrocyclic peptide binders targeting HTT. These binders exhibit low-nanomolar affinity in vitro and engage distinct HTT and HTT-HAP40 interfaces, as revealed by hydrogen-deuterium exchange mass spectrometry and cryoelectron microscopy. Chemoproteomics confirmed selective binding in cell extracts from wildtype but not HTT-null cell lines. HAP40 consistently and stoichiometrically copurified with HTT across cell lines, including with HTT variants containing different CAG repeat lengths, highlighting the broad presence of the HTT-HAP40 complex.

Huntingtin Protein↗

PubMed2025

High-Affinity, Structure-Validated and Selective Macrocyclic Peptide Tools for Chemical Biology Studies of Huntingtin.

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by a CAG repeat expansion in the Huntingtin (HTT) gene, with no disease-modifying therapies currently available. The precise molecular function of the HTT protein is unclear, and the lack of selective chemical tools has limited functional studies. We have identified and characterized macrocyclic peptide binders targeting HTT. These binders exhibit low-nanomolar affinity in vitro and engage distinct HTT and HTT-HAP40 interfaces, as revealed by hydrogen-deuterium exchange mass spectrometry and cryo-electron microscopy. Chemoproteomics confirmed selective binding in cell extracts from wildtype but not HTT-null cell lines. HAP40 consistently and stoichiometrically co-purified with HTT across cell lines, including with HTT variants containing different CAG repeat lengths, highlighting the broad presence of the HTT-HAP40 complex.

HAP40↗

PubMed2026

Unlocking the molecular engineering of Geobacillus glycoside hydrolases as a source of industrial biocatalysts.

This review examines Geobacillus sensu stricto as a source of thermostable glycoside hydrolases (GH) for biomass conversion, food processing, and enzyme engineering. Recent peer-reviewed literature was assessed with emphasis on taxonomy, genome-based Carbohydrate-Active Enzymes (CAZyme) prediction, biochemical validation, structural data, and engineering case studies. Taxonomic boundaries were interpreted using current Anoxybacillaceae frameworks, with Parageobacillus treated as a related comparator rather than as Geobacillus. The strongest evidence supports GH13 alpha-amylases, xylan-active systems, beta-xylosidases, and selected accessory enzymes. Recent studies also show that genome mining must be coupled with enzymatic assays and product profiling because CAZyme annotation alone does not prove industrial function. Molecular engineering has improved relevant traits, including the longer thermal half-life of engineered G. stearothermophilus alpha-amylase variants, the increased catalytic efficiency of oligo-alpha-1,6-glucosidase variants, and improved AmyS expression in Bacillus subtilis. Geobacillus glycoside hydrolases are best interpreted as process-specific, engineerable biocatalytic templates. Their translation requires reliable taxonomy, functional validation, structural interpretation, scalable expression and testing on realistic substrates. This synthesis also recognises current limitations: many predicted CAZymes still lack biochemical validation, complete cellulolytic systems remain less mature than xylan- and starch-active systems, and scale-up data remain scarce.

Geobacillus↗

PubMed2026

Molecular Cloning, Recombinant Expression, and In Silico Structural Analysis of Cu/Zn-Superoxide Dismutase from Trachyspermum ammi.

Superoxide dismutase (SOD) is an essential antioxidant metalloenzyme that is critical for the cellular defense against oxidative damage, as it scavenges superoxide radicals and maintains the redox status. Cytosolic Cu/Zn-SOD is particularly important in the regulation of oxidative stress among different isoforms in higher plants. While Cu/Zn-SODs from several plant species have been characterized, molecular information is limited for Trachyspermum ammi, a medicinally important member of a family Apiaceae with antioxidant potential.In the present study, an integrated molecular and in silico approach has been taken to clone and analyze a Cu/Zn type SOD gene from T. ammi to get insight into its structural and evolutionary characteristics. PCR amplification yielded an open reading frame of 456 bp encoding a protein of 152 amino acids. Sequence analysis showed that plant Cu/Zn-SODs, especially those from Daucus carota, were highly similar to one another (about 90-95%).Multiple sequence alignment confirmed the presence of conserved catalytic motifs and metal-binding histidine residues, both of which are crucial for enzymatic function. Physicochemical analysis predicted the protein to be stable, hydrophilic and compatible with cytosolic localization. The analysis of secondary structure indicated a predominance of β-strands, consistent with the conserved β-barrel architecture of plant Cu/Zn-SODs.The three-dimensional structure was built by homology modeling using a closely related plant Cu/Zn-SOD template with high sequence identity. Structural validation demonstrated an acceptable stereochemical quality with 86.3% residues in the favored region of Ramachandran plot, satisfactory ERRAT and Verify3D scores, and a low RMSD value of 0.104 Å on structural superimposition. Phylogenetic analysis placed the enzyme in the Apiaceae lineage, suggesting evolutionary conservation among related plant species. In conclusion, this study presents the first molecular and structural characterization of Cu/Zn-SOD from T. ammi and confirms the existence of a conserved structural framework typical of plant Cu/Zn-SODs. These results provide a basis for further studies concerning recombinant expression, enzymatic validation and potential relevance in antioxidant and plant stress biology.

Cloning, Molecular↗

PubMed2026

Specific Instruments for Caregiving Competence Among Family Caregivers of Cancer Patients: A COSMIN Systematic Review of Psychometric Properties.

OBJECTIVE: To evaluate and summarize the psychometric properties of specific instruments for caregiving competence among family caregivers of cancer patients. METHODS: Systematically searched eight databases for studies published up to November 2025. The methodological quality and psychometric properties of the instruments were evaluated using COSMIN 2.0. Evidence grades were rated using the modified GRADE system (four grades: "High," "Moderate," "Low," and "Very Low"), and recommendations were formulated (Category A: recommended, Category B: potential with further validation, and Category C: not recommended). RESULTS: Seven studies were included, comprising three specific instruments: the Care Competency Scale for Family Caregivers in Home Palliative Care (CCSHPC) (n = 1), the Caregiver Caregiving Self-Efficacy Scale-Oral Cancer (CSES-OC) (n = 1), and the Caring Ability of Family Caregivers of Patients with Cancer Scale (CAFCPCS) (n = 5). Both the CCSHPC and CAFCPCS received Category B recommendations, demonstrating "adequate" content validity with evidence grades rated "very low" and "low," respectively. The CAFCPCS also shows good structural validity ("moderate") and internal consistency ("low") in some cultural contexts. The CSES-OC is a Category C recommendation, with high-quality evidence indicating "inadequate" criterion validity. CONCLUSION: Few specific instruments exist, and most did not strictly follow COSMIN guidelines. The CAFCPCS is provisionally recommended based on relative evidence superiority rather than complete psychometric validation. Further cross-cultural and localized instrument development is warranted. IMPLICATIONS FOR NURSING PRACTICE: Use well-validated specific instruments to identify strengths and weaknesses in the caregiving competencies of family caregivers of cancer patients, enabling them to deliver high-quality home-based cancer care.

Female↗

PubMed2026

Computational prediction of a multi-epitope Human Metapneumovirus vaccine candidate through integrated reverse vaccinology and pan-genomic approaches.

Human metapneumovirus (HMPV) is a primary cause of global respiratory infections yet no approved vaccine currently exists. This study computationally predicts a multi-epitope vaccine candidate using a diverse dataset of 65 HMPV sequences spanning five continents. Following the screening of lead proteins for antigenicity and virulence, fifteen highly conserved MHC-I, MHC-II and B-cell epitopes were prioritized. These were integrated with a putative L7/L12 adjuvant using optimized AAY, GPGPG, and KK linkers to design three constructs (HMPV_V1-V3). Structural validation identified HMPV-V2 as the lead candidate that exhibits a Z-score of-5.24 and 87.7% of residues in favored Ramachandran regions indicating excellent stereochemical quality and structural stability. In silico docking indicated a strong predicted binding affinity between HMPV-V2 and the TLR4 receptor (energy: -969.2). Immune simulations predicted a robust adaptive response characterized by high IgG1 titers, memory B-cell maturation, and a Th1-dominant cytokine profile. Furthermore, molecular dynamics simulations suggested exceptional structural integrity for HMPV-V2, maintaining a low RMSD of 8.213 and RMSF of 0.737 throughout the simulation. Optimized in silico cloning into the pET28a (+) vector indicated a high potential for protein expression in E. coli systems. While these findings provide a theoretically grounded blueprint for vaccine development, this study is entirely computational and lacks experimental validation. Further in vitro and in vivo testing is required to confirm the actual safety and immunogenicity of the proposed candidate.

Metapneumovirus↗

PubMed2025

Genomic prediction and genome-wide association study for liver abscesses in crossbred beef cattle.

Liver abscesses are a concern in feedlot cattle, and little is known about the role of genetics in their development. This study aimed to estimate genetic parameters and to identify single-nucleotide polymorphisms (SNPs) associated with liver abscesses. Crossbred cattle representing 18 breeds in the U.S. Meat Animal Research Center Germplasm Evaluation Program were phenotyped for liver abscesses at slaughter (n = 9,044). Seventeen percent of cattle had liver abscesses. These cattle had genotypes that were imputed to sequence variant genotypes. After filtering and quality control, 340,723 SNPs were used in the analysis. Liver abscess prevalence was modeled with a single-step genomic best linear unbiased prediction (ssGBLUP) threshold model using a Bayesian framework. The model included contemporary group (sex, treatment group, and slaughter date), additive genomic, and residual effects. Genomic heritability was 0.039 (95% highest posterior density = 0.005, 0.081), which was very small. To assess prediction quality, a 5-fold random cross-validation structure was used. Method Linear Regression was used to assess accuracy, bias, and dispersion by comparing estimated breeding values (EBV) from full and reduced analyses. Cross-validation metrics showed EBV based on genotypes had 0.05 reliability (SD < 0.01) with no bias relative to EBV based on genotypes and phenotypes. For the genome-wide association study, SNP effects were back calculated from the EBV solutions from ssGBLUP. No SNPs were associated with liver abscesses at a Benjamini-Hochberg adjusted 0.05 significance level. Although a large dataset was used, this result was because of the low genomic heritability and imprecise EBV used to calculate SNP effects. Based on these results, environmental factors contribute to most of the variation in liver abscesses. Genetic selection to reduce liver abscesses would be slow because of the low genomic heritability, measurement late in life, and inability to measure breeding animals. A faster approach would be finding additional environmental interventions that maintain animal performance.

Animals↗

PubMed2025

Leveraging chemical synthesis to discover metabolites from the gut microbiome.

The gut microbiome has the biosynthetic potential to make a variety of secondary metabolites or natural products, which serve as molecular messages between cells and organisms. These chemical signals are capable of affecting physiology and behavior in real time, and are, therefore, bioactive and can exhibit medicinal properties including anticancer, antimicrobial, or immunomodulating activities. It is clearly important to identify signaling molecules in the human gut, but elucidating their chemical structures can be challenging since traditional isolation methods are typically not available. The discovery of microbiome-related metabolites requires multidisciplinary collaboration, where chemical synthesis often plays an essential role. This review highlights examples where synthetic chemistry was used to study novel metabolites produced by the gut microbiota. In the first part, we describe examples where organic synthesis was utilized in traditional contexts, as a last step for validating structures and sourcing material for biological testing. The final section of this review discusses next-generation applications for chemical synthesis, where integration with metabolomic or genomic analysis simultaneously uncovers both structural and biological information about small molecules from the gut.

Gastrointestinal Microbiome↗

PubMed2026

Regional genomic analysis of lineage distribution and transferable multidrug resistance among chicken-associated Salmonella Kentucky isolates in China.

Salmonella enterica serovar Kentucky is an important multidrug-resistant foodborne pathogen in the poultry meat supply chain. Although recent broader genomic studies have elucidated the population structure and epidemiological significance of major lineages in China (e.g., ST198 and ST314), the regional dynamics within local poultry supply chains remain insufficiently characterized. In this study, 31 chicken meat-derived isolates from Shanghai and 39 publicly available genomes from China were analyzed using antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis, conjugation experiments, and complete sequencing of representative plasmids. This enabled a systematic characterization of the molecular epidemiological features of the population and the mechanisms underlying resistance dissemination. Population genomic analysis revealed a lineage composition markedly different from the global epidemiological pattern: ST314 was the predominant sequence type among the Shanghai chicken-derived isolates (74.2%), whereas the internationally recognized high-risk clone ST198 accounted for only 25.8% of the local isolates. However, risk stratification analysis indicated that although ST198 was detected less frequently, it carried a significantly greater burden of acquired resistance genes and therefore represented a higher-risk resistant lineage. Functional and structural validation further elucidated the molecular basis of resistance dissemination within this high-risk lineage. Conjugation experiments confirmed the co-transfer of a multidrug resistance module carrying blaTEM-1 and blaCTX-M-267 to the recipient strain Escherichia coli J53. Complete plasmid analysis revealed that these two β-lactam resistance genes were co-localized on a 242-kb transferable plasmid flanked by Tn1331, Tn3, and multiple transposase-associated elements, thereby providing a structural basis for their horizontal transfer. This study provides important molecular epidemiological evidence for lineage-specific surveillance and risk-stratified control of resistant Salmonella in the poultry meat supply chain and further underscores the need for continuous monitoring of mobile genetic elements within a One Health framework.

Animals↗

PubMed2026

Instruments for measuring body image in breast cancer patients: a systematic review of measurement properties.

PURPOSE: To evaluate the psychometric properties of PROMs for measuring body image in breast cancer patients. METHODS: In December 2024, a psychometric systematic review was performed in the nine databases. The COSMIN checklist was employed to evaluate the methodological quality and psychometric properties of the included body image measures. The level of evidence was assessed using the GRADE framework, and final recommendations were formulated for the scale. RESULTS: Thirty-eight articles evaluating fifteen PROMs were included in this review. Structural validity, internal consistency, and hypothesis testing had been most frequently evaluated. Measurement error had not been assessed for all PROMs. Twelve instruments show potential application value but require further research. The BAS-BC, PSPP, and ASI-R are not recommended for use, as these instruments do not meet the strict COSMIN thresholds for full recommendation. CONCLUSION: The BIS can be recommended as a temporary screening tool for assessing body image outcome in clinical practice. The BIRS can be tentatively advised for measuring specific postoperative body image changes. However, further comprehensive studies are required to validate the psychometric properties of existing PROMs.

Female↗

PubMed2026

Patient-reported outcome measures for depression or anxiety symptoms in patients with cardiovascular disease: A COSMIN systematic review.

BACKGROUND: Depression and anxiety are common in patients with cardiovascular disease (CVD), but the measurement quality of patient-reported outcome measures (PROMs) used in this population remains unclear. This review aimed to evaluate the methodological quality, measurement properties, and certainty of evidence for depression and anxiety PROMs in adults with CVD and to inform instrument selection. METHODS: Following COSMIN and PRISMA guidance, four databases were searched from inception to February 2026. Studies assessing measurement properties of PROMs in adults with CVD were included. Methodological quality was evaluated using the COSMIN Risk of Bias checklist, and certainty of evidence was graded using an adapted GRADE approach. RESULTS: Sixty-six studies assessing 38 PROMs were included, comprising 29 generic and 9 CVD-specific instruments. Six PROMs met COSMIN Category A criteria: Cardiac Depression Scale-Short Form, Patient Health Questionnaire-9, Beck Depression Inventory-II, Hospital Anxiety and Depression Scale, Generalized Anxiety Disorder-7, and Major Depression Inventory. Four instruments were classified as Category C because of insufficient structural validity. Content-validity evidence was largely indeterminate or of limited certainty. Only 24 studies used confirmatory factor analysis or Rasch analysis, and no study assessed measurement error or responsiveness. Cross-cultural validity evidence was scarce. CONCLUSIONS: Six PROMs met Category A criteria, but selection should remain purpose- and context-specific. Particular attention should be given to somatic symptom overlap and intended clinical use. Further validation should prioritize content validity, measurement invariance, responsiveness, measurement error, and clinimetric performance.

Humans↗

PubMed2026

Multitargeted comparative evaluation suggests 2-Aoeobenoxmide shows favourable in silico binding compared to Tucatinib against ERα, HER2, AKT1, EGFR, and PIK3CA in breast cancer.

Breast cancer is a leading cause of cancer-related morbidity and mortality globally, with the WHO reporting approximately 2.3 million new cases and 685,000 deaths annually. Drug resistance in breast cancer complicates treatment, with mutations in critical proteins contributing to therapy failure. Key oncogenic proteins involved in breast cancer progression-namely ERα (a ligand-activated nuclear receptor; PDB: 1A52) and the kinase domains of HER2 (PDB ID: 3PP0), AKT1 (PDB ID: 4EJN), EGFR (PDB ID: 4I23) and PIK3CA (PDB ID: 7R9V)-are pivotal in tumour progression and resistance mechanisms. Targeting these proteins using multitargeted therapeutic strategies may overcome resistance by disrupting key signalling pathways involved in cell proliferation, survival, and metastasis. Such combinatorial approaches promise to improve treatment efficacy and patient outcomes in cases of resistant breast cancer. In this study, we performed multitarget docking on prepared and validated protein structures against the ZINC natural compound library using HTVS, SP, and XP, with pose validation using MM-GBSA. We identified 2-Aoeobenoxmide (2-[1-(2-amino-2-oxo-ethoxy)-6-oxo-benzo[c]chromen-3-yl]oxyacetamide, ZINC134008) with docking and MM-GBSA scores ranging from -8.162 to -10.327 kcal/mol and from -47.18 to -57.62 kcal/mol, respectively, and compared the results with the FDA-approved drug Tucatinib, which exhibited lower binding affinity scores. We further evaluated pharmacokinetic properties using QikProp and electronic properties using DFT (Jaguar) and compared the descriptors of 2-Aoeobenoxmide with those of Tucatinib and with accepted reference ranges. We also performed the WaterMap for 5 nanoseconds (ns), computed various energies, interactions and hydration sites, and the comparison suggests that 2-Aoeobenoxmide shows more favourable hydration-site displacement and binding interactions than Tucatinib. Additionally, a 100 ns MD Simulation has resulted in far less deviation, fluctuations, and intermolecular interactions than Tucatinib, suggesting stable protein-ligand interactions, while the binding free energy and total complex energy computed across 0-1000 frames of the MD trajectories indicate that 2-Aoeobenoxmide is a promising in silico candidate. Importantly, because the entire study is computational, the findings should be interpreted as in silico hypotheses, and experimental validation through in vitro and in vivo assays is warranted before any clinical translation is considered.

Humans↗

PubMed2026

Phenotyping strategies for chronic overlapping pain conditions and internalizing disorders in Veterans: Prevalence, comorbidity, and latent structure as evidence for construct validity.

Chronic overlapping pain conditions (COPCs), internalizing (INT) disorders, and opioid use disorder (OUD) are common, comorbid, and difficult to phenotype at scale. Electronic health record (EHR) studies commonly define cases using Any Code (AC; ≥1 ICD-9/10 code) and Multiple Code (MC; ≥1 inpatient or ≥2 outpatient codes) phenotyping strategies, but it is unclear whether these thresholds change only case numbers or also the clinical relationships among conditions. This cross-sectional study included approximately 950,000 Million Veteran Program participants with ≥2 visits. AC and MC phenotypes for 17 conditions spanning COPCs, INT, and OUD were compared in prevalence, case characteristics, comorbidity, and latent structure. Random-thinning analysis compared AC-MC differences to case reduction alone. Construct validity was evaluated through correspondence with expected patterns of association and latent organization. Back pain (AC=58.1%; MC=48.1%), major depressive disorder (41.5%; 36.2%), and post-traumatic stress disorder (32.6%; 29.1%) were most prevalent. MC excluded 33.5% of AC cases on average, and MC cases had greater healthcare utilization, diagnostic burden, opioid exposure, and psychiatric medication use than AC-only cases. The observed mean absolute correlation change (mean |Δr|=0.014) was smaller than in all 1000 random-thinning replicates. Both strategies supported a correlated, four-factor model consistent with "Anxious Misery," "Fear," "Diffuse Pain," and "Head Pain" (AC: CFI=0.987, RMSEA=0.015; MC: CFI=0.987, RMSEA=0.014). The MC strategy reduced prevalence and altered case composition but maintained the expected comorbidity and latent organization patterns among conditions. Findings provide evidence of phenotype construct validity and inform selection of EHR phenotyping strategies for epidemiological and genomic research. PERSPECTIVE: Commonly used EHR phenotyping strategies tested in nearly one million Veterans produce broadly similar latent organization across comorbid and prevalent chronic overlapping pain conditions, internalizing disorders, and opioid use disorder. Findings support construct validity and clarify trade-offs involving case inclusion, recorded burden, and healthcare observation in large-scale research.

Chronic overlapping pain conditions↗

PubMed2026

Genomic and epigenetic regulatory mechanisms in exercise-based rehabilitation processes: Cellular and tissue remodeling, microvascular adaptation, and circulating biomarkers.

While exercise-based rehabilitation is known to positively impact functionally related parameters, the role of genomic and epigenomic responses coordinated with cellular, extracellular matrix (ECM), mitochondrial, and microvascular adaptations remains insufficiently investigated. This narrative review summarizes mechanistic evidence linking exercise-associated mechanical, metabolic, hypoxia-redox, inflammatory, and hemodynamic stimuli with tissue remodeling and clinically relevant biomarkers. Current findings indicate that integrin-focal adhesion kinase (FAK) signaling and Hippo YAP/TAZ pathways contribute to mechanical signal transduction, cytoskeletal regulation, and gene expression, whereas metabolic adaptation, ATP homeostasis, and protein synthesis are regulated through AMPK-PGC-1α, SIRT1, and mTOR-dependent pathways. Epigenetic mechanisms, including DNA methylation, histone modifications, chromatin remodeling, and noncoding RNA regulation, further influence cell-specific responses in myofibers, satellite cells, fibro-adipogenic progenitors, endothelial cells, pericytes, and immune cells. In addition, VEGF-VEGFR2, eNOS-NO, and KLF2/KLF4 signaling, together with extracellular matrix turnover and inflammation resolution, contribute to tissue repair and microvascular adaptation during rehabilitation. Importantly, acute exercise-induced molecular responses should not be interpreted as direct evidence of sustained tissue adaptation. Circulating microRNAs, extracellular vesicles, cell-free DNA, collagen-related markers, and vascular proteins represent promising approaches for monitoring rehabilitation-related changes; however, their clinical translation remains limited by challenges related to tissue specificity, biomarker kinetics, analytical variability, and the need for standardized validation alongside structural and functional outcomes.

AMPK–PGC-1α signaling↗

PubMed2024

Molecular basis for antibody recognition of multiple drug-peptide/MHC complexes.

The HapImmuneTM platform exploits covalent inhibitors as haptens for creating major histocompatibility complex (MHC)-presented tumor-specific neoantigens by design, combining targeted therapies with immunotherapy for the treatment of drug-resistant cancers. A HapImmune antibody, R023, recognizes multiple sotorasib-conjugated KRAS(G12C) peptides presented by different human leukocyte antigens (HLAs). This high specificity to sotorasib, coupled with broad HLA-binding capability, enables such antibodies, when reformatted as T cell engagers, to potently and selectively kill sotorasib-resistant KRAS(G12C) cancer cells expressing different HLAs upon sotorasib treatment. The loosening of HLA restriction could increase the patient population that can benefit from this therapeutic approach. To understand the molecular basis for its unconventional binding capability, we used single-particle cryogenic electron microscopy to determine the structures of R023 bound to multiple sotorasib-peptide conjugates presented by different HLAs. R023 forms a pocket for sotorasib between the VH and VL domains, binds HLAs in an unconventional, angled way, with VL making most contacts with them, and makes few contacts with the peptide moieties. This binding mode enables the antibody to accommodate different hapten-peptide conjugates and to adjust its conformation to different HLAs presenting hapten-peptides. Deep mutational scanning validated the structures and revealed distinct levels of mutation tolerance by sotorasib- and HLA-binding residues. Together, our structural information and sequence landscape analysis reveal key features for achieving MHC-restricted recognition of multiple hapten-peptide antigens, which will inform the development of next-generation therapeutic antibodies.

Humans↗

PubMed2026

Sperm subpopulations differing in mitochondrial abundance show divergent nuclear allele frequencies.

Mammalian ejaculates contain heterogeneous sperm subpopulations that differ in subcellular architecture and developmental history, despite appearing morphologically uniform. The extent to which this cellular heterogeneity reflects underlying nuclear genomic structure within a sire remains largely unexplored. Mitochondrial architecture in sperm is established during spermatogenesis, with final assembly and organization occurring during spermiogenesis under nuclear genomic control, positioning variation in mitochondrial abundance and organization as a potential phenomic indicator of within-sire allelic segregation. Here, we tested whether sperm subpopulations defined by differing mitochondrial abundance exhibit systematic differences in nuclear allele representation. Boar sperm were resolved into low and high mitochondrial subpopulations using fluorescence-activated cell sorting based on MitoTracker™ Green fluorescence while excluding debris, doublets, and non-viable cells. Epifluorescence microscopy confirmed that high MitoTracker™ Green fluorescence sperm possessed longer mitochondrial sheaths, validating a structural distinction between subpopulations. Whole-genome sequencing of paired mitochondrial subpopulations from three boars was performed, and allelic ratio distortion was evaluated relative to heterozygous baseline populations. Analyses across heterozygous loci genome-wide identified candidate allele frequency shifts between mitochondrial-defined subpopulations, suggesting non-random segregation of alleles within ejaculates. Using a minimum sequencing depth of 30 reads in both sorted fractions, 182 candidate SNPs were identified with evidence of allele-frequency differences between mitochondrial fluorescence-defined subpopulations. These findings suggest that sperm mitochondrial abundance can potentially serve as an indirect, high-throughput marker of nuclear genomic heterogeneity within sires. This proof-of-concept framework establishes a foundation for future studies integrating sperm phenotyping, genome-wide allele-frequency analysis and functional validation to better characterize gamete-level heterogeneity.

Male↗

PubMed2026

Genomic and Molecular Interaction Analysis of NodD1 in a Novel Bradyrhizobium yuanmingense sp. B64 Isolate for Nodulation and Symbiosis of Legume Plants.

Rhizobial bacteria are known for their ability to fix nitrogen for leguminous plants and their essential function for sustainable agriculture. This study characterizes the taxonomic status and functional potential of the Bradyrhizobium B64 isolate using integrated genomic and molecular approaches. The whole genome of the B64 isolate was sequenced via Illumina paired-end technology. Species delimitation was performed using average nucleotide identity (ANI) and digital DNA-DNA Hybridization (dDDH). The NodD1 protein structure was modeled using AlphaFold3 and validated by Ramachandran plot analysis. Molecular docking was then conducted to evaluate interactions between NodD1 and four signaling flavonoids: Apigenin, Daidzein, Genistein, and Naringenin. Genomic analysis revealed a maximum ANI of 94.4% and dDDH values between 51.4 and 62.4%. Since these values fall below the standard prokaryotic thresholds (ANI < 95%; dDDH < 70%), the B64 isolate is identified as a novel species. Physiological assays confirmed nitrogen fixation (1.97 ppm), IAA production (3.67 ppm), and phosphate solubilization (26.10 ppm). Structural validation showed 100% of NodD1 residues in allowed regions, ensuring high model reliability. Docking simulations demonstrated strong binding affinities across all flavonoids, with binding free energies ranging from - 8.8 to - 9.0 kcal/mol. Daidzein exhibited the highest thermodynamic stability (- 9.0 kcal/mol), whereas apigenin showed the most extensive residue interaction network. The B64 isolate is a novel Bradyrhizobium species with a high symbiotic capacity. The stable NodD1-flavonoid interactions provide a molecular basis for efficient nodulation, positioning B64 as a promising candidate for developing lipo-chitooligosaccharide (LCO)-based biofertilizers.

Bradyrhizobium↗

PubMed2026

Seawater immersion reshapes the temporal dynamics of traumatic brain injury and reveals mitochondrial oxidative stress as a modifiable therapeutic target.

Traumatic brain injury (TBI) evolves through time-dependent secondary injury, but whether seawater (SW) immersion merely amplifies pathology or reshapes the temporal trajectory of post-traumatic biology remains unclear. Here, we applied time-resolved proteomics to mouse brains after controlled cortical impact (CCI) with or without artificial SW immersion at 1, 3, 7, and 28 days post-injury. Trajectory-based proteomic analysis revealed that SW immersion altered the direction, magnitude, timing, persistence, and recovery of protein responses, rather than simply intensifying TBI-induced changes. This remodeled trajectory exhibited phase-specific patterns, including SW-dominant, synergistically enhanced, and attenuated responses, highlighting mitochondrial oxidative stress, inflammatory activation, complement/coagulation disturbance, and impaired structural repair. Phenotypic validation confirmed phase-specific deficits, including acute inflammatory-redox injury, impaired neuronal survival, chronic axon-myelin disruption, and incomplete behavioral recovery. SS-31 partially mitigated selected inflammatory, redox, neuronal, and white matter abnormalities, supporting mitochondrial oxidative stress as a modifiable node rather than the sole driver of trajectory remodeling. These findings identify seawater immersion as a temporal modifier of secondary injury and emphasize that environmental trauma may require trajectory-informed, phase-specific therapeutic interventions.

Animals↗