Search Results (24,063)

Voltage-gated Na⁺ channels (Nav) are the molecular determinants of action potential initiation and propagation. Among the nine voltage-gated Na⁺ channel isoforms (Nav1.1–Nav1.9), Nav1.2 and Nav1.6 are of particular interest because of their developmental expression profile throughout the central nervous system (CNS) and their association with channelopathies. Although the α-subunit coded by each of the nine isoforms can sufficiently confer transient Na⁺ currents (I_Na), in vivo these channels are modulated by auxiliary proteins like intracellular fibroblast growth factor (iFGFs) through protein–protein interaction (PPI), and probes developed from iFGF/Nav PPI complexes have been shown to precisely modulate Nav channels. Previous studies identified ZL0177, a peptidomimetic derived from a short peptide sequence at the FGF14/Nav1.6 PPI interface, as a functional modulator of Nav1.6-mediated I_Na⁺. However, the isoform specificity, binding sites, and putative physiological impact of ZL0177 on neuronal excitability remain unexplored. Here, we used automated planar patch-clamp electrophysiology to assess ZL0177’s functional activity in cells stably expressing Nav1.2 or Nav1.6. While ZL0177 was found to suppress I_Na in both Nav1.2- and Nav1.6-expressing cells, ZL0177 elicited functionally divergent effects on channel kinetics that were isoform-specific and supported by differential docking of the compound to AlphaFold structures of the two channel isoforms. Computational modeling predicts that ZL0177 modulates Nav1.2 and Nav1.6 in an isoform-specific manner, eliciting phenotypically divergent effects on action potential discharge. Taken together, these results highlight the potential of PPI derivatives for isoform-specific regulation of Nav channels and the development of therapeutics for channelopathies. Full article

MRGPRX2 (Mas-related G protein-coupled receptor member X2) is implicated in mast cell (MC)-driven disorders due to its ability to bind diverse ligands, which may be G-protein-biased or balanced, with the latter activating both G-proteins and the β-arrestin pathway. Icatibant, a peptide drug, produces injection-site reactions in most patients and is used experimentally to probe MRGPRX2 function in skin tests. While reported to be G-protein-biased, it is unknown how skin MCs respond to icatibant, although these are the primary target cells during therapy. We therefore compared responses to icatibant with those induced by the balanced agonist substance P (SP) in skin MCs. Degranulation and desensitization were assessed via β-hexosaminidase release, receptor internalization by flow cytometry, and downstream signaling by immunoblotting. Skin MCs degranulated in response to SP and icatibant, relying on Gi proteins and calcium channels; Gq and PI3K (Phosphoinositide 3-kinase) contributed more strongly to exocytosis following icatibant, while JNK (c-Jun n-terminal kinase) was more relevant for SP. Both agonists activated ERK, PI3K/AKT, and (weakly) p38. Surprisingly, and in contrast to the LAD2 (Laboratory of Allergic Diseases 2 mast cell line) MC line, icatibant was at least as potent as SP in eliciting MRGPRX2 internalization and (cross-)desensitization in skin MCs. These findings suggest that icatibant functions differently in primary versus transformed MCs, acting as a fully balanced ligand in the former by triggering not only degranulation but also receptor internalization and desensitization. Therefore, not only the ligand but also the MRGPRX2-expressing cell plays a decisive role in whether a ligand is balanced or biased. These findings are relevant to our understanding of icatibant’s clinical effects on edema and itch. Full article

Background/Objectives: Non-Hodgkin lymphoma (NHL) is a group of blood cancers that arise in the lymphatic nodes and other tissues after an injury to the DNA of B/T lineage and NK lymphocytes. Recently, we reported that incomptine A (IA) has in vivo antilymphoma properties. This research aimed to evaluate the effects of IA in the treatment of NHL using antilymphoma activity, Tandem Mass Tag (TMT), and bioinformatics approaches. Methods: The antilymphoma activity of IA was tested on male Balb/c mice inoculated with U-937 cells. Also, TMT, gene ontology enrichment, Reactome pathway, Kyoto Encyclopedia of Gene and Genomes pathway, molecular docking, toxicoinformatic, and pharmaceutical analyses were performed. Results: By TMT analysis of the altered levels of proteins present in the lymph nodes of Balb/c mice with NHL and treated with IA, we identified 106 significantly differentially expressed proteins (DEPs), including Il1rap, Ifi44, Timd4, Apoa4, and Fabp3 as well as Myh3, Eno 2, and H4c11. Among these, the Fhl1 result was the most important cluster altered and a potential core target of IA for the treatment of NHL. Network pharmacology studies have revealed that DEPs are associated with processes such as muscle contraction, glycolysis, hemostasis, epigenetic regulation of gene expression, transport of small molecules, neutrophil extracellular trap formation, adrenergic signaling in cardiomyocytes, systemic lupus erythematosus, alcoholism, and platelet activation, signaling, and aggregation. Computational studies revealed strong binding affinities with six proteins associated with cancer, positive pharmacokinetic properties, and no toxicity. Conclusions: Our contribution suggests that IA may be a compound with potential therapeutic effects against NHL. Full article

The hyaluronidase enzyme derived from Vespa tropica (VesT2a) venom contains two putative catalytic residues. Herein, a double mutation was introduced into VesT2a at its catalytic sites by substituting Asp107 and Glu109 with Asn and Gln, respectively, to assess their essential roles in enzymatic function. We used Pichia pastoris to produce the mutated version of the VesT2a (mVesT2a) protein, and the process was more efficient when employing the methanol-inducible promoter (P_AOX1) compared to the constitutive promoter (P_GAP). In bioreactor scale-up, P. pastoris harboring the pAOX1-αMF-mVesT2a plasmid secreted 34.03 ± 2.31 mg/L of mVesT2a, with an apparent molecular mass of 46.6 kDa, retaining only 2.9% of hyaluronidase activity, thus indicating successful mutation. The newly developed indirect ELISA-based method using mVesT2a demonstrated its potential as an alternative approach for measuring hyaluronic acid (HA) at low concentrations and was also used to confirm HA-binding capacity. In silico docking and molecular dynamics simulations further supported the stable interaction of the mVesT2a–HA complex while suggested other surrounded acidic amino acid residues, which may play a minor role in HA degradation, supporting the remaining activity observed in the in vitro experiments. Full article

Excessive stress disrupts cardiac homeostasis via complex and multifactorial mechanisms, resulting in cardiac dysfunction, cardiovascular disease, or even sudden cardiac death, yet the underlying molecular mechanisms remain poorly understood. Accordingly, we aimed to elucidate how stress induces calcium dysregulation and contributes to cardiac dysfunction and injury through the nuclear receptor subfamily 3 group c member 1 (NR3C1)/Glomulin (GLMN)/FK506-binding protein 12.6 (FKBP12.6) signaling pathway. Using mouse models of acute and chronic restraint stress, we observed that stress-exposed mice exhibited reduced left ventricular ejection fraction, ventricular wall thickening, elevated serum and myocardial cTnI levels, along with pathological features of myocardial ischemia and hypoxia, through morphological, functional, and hormonal assessments. Using transmission electron microscopy and Western blotting, we found that stress disrupted mitochondrial quality control in cardiomyocytes, evidenced by progressive mitochondrial swelling, cristae rupture, decreased expression of fusion proteins (MFN1/OPA1) and biogenesis regulator PGC-1α, along with aberrant accumulation of fission protein (FIS1) and autophagy marker LC3. At the cellular level, ChIP-qPCR and siRNA knockdown confirmed that stress activates the glucocorticoid receptor NR3C1 to repress its downstream target GLMN, thereby preventing FKBP12.6 ubiquitination and degradation, resulting in calcium leakage and overload, which ultimately impairs mitochondrial quality control and damages cardiomyocytes. In conclusion, our findings reveal that stress induces myocardial damage through NR3C1/GLMN-mediated FKBP12.6 ubiquitination, disrupting calcium homeostasis and mitochondrial quality control, and lay a theoretical foundation for dissecting the intricate molecular network of stress-induced cardiomyopathy. Full article

Phytoglobins (Pgbs) are plant hemoglobin-like proteins with key roles in nitric oxide (NO) scavenging, oxygen sensing, and hypoxic stress responses. Their typical hexacoordination results in unusually high affinities for gaseous ligands such as NO and carbon monoxide (CO), complicating measurement using conventional methods. Standard assays often require large sample volumes and lack sensitivity for high-affinity, low-abundance proteins like hexacoordinated Pgbs. Here, we present a microscale capillary-based fluorescence assay for the high-precision measurement of protein–gas binding. Fluorophore-labeled proteins are loaded into gas-saturated capillaries and analyzed via dual-wavelength fluorescence to monitor isothermal spectral shifts upon ligand binding. Phosphate-buffered saline with Tween20 (PBS-T20) ensures gas stability and minimizes nonspecific adsorption. Using this approach, we characterized CO and NO binding to the recombinant wildtype (rWT) of Beta vulgaris Pgb 1.2 (BvPgb 1.2) and its C86A mutant. CO titrations revealed biphasic binding, with EC₅₀ ~400 nM and ~700 μM (rWT) and ~500 nM and ~400 μM (C86A). NO binding showed K_D values of ~1600 nM (rWT) and ~400 nM (C86A), implicating Cys86 in ligand affinity. This assay provides a robust, low-volume method for high-affinity protein–gas studies and shows biphasic dynamics in BvPgbs. Full article

Drought is the single largest abiotic threat to soybean yield, yet the lectin genes that mediate drought perception and signaling in this crop have never been systematically mapped. We reanalyzed the public RNA-seq dataset GSE237798 (Williams 82 leaves, 7-day water withdrawal) with an updated fastp–HISAT2–featureCounts–DESeq2 pipeline and a curated catalog of 359 soybean lectin loci. Of the 127 lectin transcripts showing any drought-dependent shift, only 15 were stringently differentially expressed with substantial fold changes: 7 were upregulated and 8 downregulated. These genes span four families, GNA, legume, LysM and Nictaba-related lectins, and are heavily biased toward lectin receptor-like kinases (11 of 15), pinpointing the plasma membrane as the main control node. Gene Ontology enrichment highlights protein autophosphorylation and signal-transduction terms, and the inspection of AlphaFold models together with established lectin knowledge indicates that G- and L-type lectin domains have largely lost canonical carbohydrate-binding residues, whereas LysM and Nictaba proteins retain conserved folds compatible with ligand binding. The data expose a focused, modular lectin program rather than the broad activation often assumed: most soybean lectins stay silent under drought conditions, and only a defined subset toggles their expression, albeit mildly. Full article

Adoxophyes orana (Lepidoptera: Tortricidae) is a significant polyphagous leafroller that damages trees and shrubs in Rosaceae and other families. However, the molecular mechanisms by which this pest recognizes sex pheromones and host plant volatiles remain largely unknown. Tissue expression profiles indicated that two general odorant-binding proteins (AoraGOBP1 and AoraGOBP2) were more abundant in the antennae and wings of both sexes, with AoraGOBP1 being rich in the female head and abdomen. Temporal expression profiles showed that AoraGOBP1 was expressed at the highest level in 5 day-nmated adults, while AoraGOBP2 exhibited high expression in 5 day-unmated, 7 day-unmated, and mated female adults. Fluorescence competitive binding assays of heterologous expressed AoraGOBPs demonstrated that AoraGOBP2 strongly bound to the primary sex pheromone Z9-14:Ac, and two minor sex pheromones Z9-14:OH and Z11-14:OH, whereas AoraGOBP1 only showed a high binding affinity to Z9-14:Ac. What is more, AoraGOBP1 exhibited a broader binding spectrum for host plant volatiles than AoraGOBP2. Molecular dockings, molecular dynamic simulations, and per-residue binding free decompositions indicated that the van der Waals interaction was the predominant contributor to the binding free energy. Electrostatic interactions between aldehydes, or alcohols and AoraGOBPs stabilized the conformational structures. Phe12 from AoraGOBP1, and Phe13 from AoraGOBP2 were identified as the most important residues that contributed to bind free energy. Our findings provide a comprehensive insight into the molecular mechanisms of olfactory recognition in A. orana, facilitating the development of chemical ecology-based approaches for the control. Full article

This study investigated the molecular mechanisms by which phthalates induce depression, utilizing network toxicology and molecular docking techniques. By integrating the TargetNet, GeneCards, and PharmMapper databases, 658 potential target genes of phthalates were identified. Additionally, 5433 depression-related targets were retrieved from the GeneCards and OMIM databases. Comparative analysis revealed 360 common targets implicated in both phthalate action and depression. A Protein-Protein Interaction (PPI) network was constructed using the STRING database. Subsequently, the CytoHubba plugin (employing the MCC algorithm) within Cytoscape was used to screen the network, identifying the top 20 hub genes. These core genes include AKT1, CASP3, TNF, TP53, BCL2, and IL6, among others. Validation on the GEO dataset (GSE23848) revealed that the expression of multiple core genes was significantly upregulated in patients with depression (p < 0.05). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that phthalates mainly regulate biological processes such as extracellular stimulus response, lipopolysaccharide metabolism, and chemical synaptic transmission. Depression is mediated by the AGE-RAGE signaling pathway (a complication of diabetes), lipids and atherosclerosis, Endocrine resistance, and the PI3K-Akt signaling pathway. Molecular docking confirmed that phthalates have strong binding activity with key targets (CASP3, TNF, TP53, BCL2, IL6). These findings present a novel paradigm for evaluating the health risks posed by environmental pollutants. Full article

Linezolid (LNZ) is a synthetic oxazolidinone antibiotic that inhibits bacterial protein synthesis through binding to ribosomal RNA, also preventing the assembly of the initiation complex during translation. It is one of the last-line therapeutic options for serious infections caused by problematic Gram-positive pathogens, including vancomycin-resistant and multidrug-resistant Enterococcus species. Data from recent large-scale studies show a 2.5-fold increase in the prevalence of clinical LNZ-resistant enterococci (LRE) over the past decade with a global detection rate of 1.1% for LNZ-resistant E. faecium (LREfm) and 2.2% for LNZ-resistant E. faecalis (LREfs). Most reported cases have originated from China, followed by South Korea and the United States. LREfm typically belongs to the high-risk clonal complex 17, whereas LREfs demonstrates a heterogeneous population structure. Mutations in the 23S rRNA and ribosomal proteins, as well as acquired resistance genes such as cfr, optrA, and poxtA are involved in the development of LNZ resistance among enterococci. Whole-genome sequencing (WGS) has been recognized as a gold standard for identifying the underlying molecular mechanisms. It exposes that numerous LRE isolates possess multiple LNZ resistance determinants and mutations, further complicating the treatment strategies. The present review article summarizes all known mutational and non-mutational LNZ resistance mechanisms and presents a global overview of WGS-based studies with emphasis on resistome analysis of clinical LREfs and LREfm isolates published in the literature during the period 2014–2025. Full article

Background: Trimetazidine is a clinically established cardioprotective agent with anti-ischemic and antioxidant properties, widely used in the management of coronary artery disease. Combining its metabolic and cytoprotective effects with the potent anti-inflammatory activity of profens presents a promising therapeutic strategy. Methods: Five novel trimetazidine–profen hybrid compounds were synthesized using N,N′-dicyclohexylcarbodiimide-mediated coupling and structurally characterized by NMR and high-resolution mass spectrometry. Their antioxidant activity was evaluated by hydroxyl radical scavenging assays (HRSA), and the anti-inflammatory potential was assessed via the inhibition of albumin denaturation (IAD). Lipophilicity was determined chromatographically. Molecular docking and 100 ns molecular dynamics simulations were performed to investigate the binding modes and stability in human serum albumin (HSA) binding sites. The acute toxicity of the hybrid molecules was predicted in silico using GUSAR software. Results: All synthesized hybrids demonstrated varying degrees of biological activity, with compound 3c exhibiting the most potent antioxidant (HRSA IC₅₀ = 71.13 µg/mL) and anti-inflammatory (IAD IC₅₀ = 108.58 µg/mL) effects. Lipophilicity assays indicated moderate membrane permeability, with compounds 3c and 3d showing favorable profiles. Docking studies revealed stronger binding affinities of S-enantiomers, particularly 3c and 3d, to Sudlow sites II and III in HSA. Molecular dynamics simulations confirmed stable ligand–protein complexes, highlighting compound 3c as maintaining consistent and robust interactions. The toxicity results indicate that most hybrids, particularly compounds 3b–3d, exhibit a favorable safety profile compared to the parent trimetazidine. Conclusion: The hybrid trimetazidine–profen compounds synthesized herein, especially compound 3c, demonstrate promising dual antioxidant and anti-inflammatory therapeutic potential. Their stable interaction with serum albumin and balanced physicochemical properties support further development as novel agents for managing ischemic heart disease and associated inflammatory conditions. Full article

SSB proteins play essential roles in DNA replication, recombination, and repair in bacteria, archaea, and eukarya. This study investigates the transcript levels, identification, expression and purification, subcellular localization, and immune protective potential of the SSB-like proteins of Eimeria necatrix (EnSSB), exploring its role in the development of E. necatrix and its potential as a candidate antigen for a subunit vaccine against avian coccidiosis. The level of EnSSB gene transcription was highest in unsporulated oocysts (UO), followed by gametocytes (GAM) (p < 0.05). The gene consisted of an open reading frame of 1488 nucleotides encoding a protein of 495 amino acid residues with a predicted molecular weight of 53.31 kDa. EnSSB contained a SSB domain with a conserved OB (oligonucleotide/oligosaccharide binding) fold. The molecular mass of the native protein, as determined by Western blot analysis, was ~58 kDa in second-generation merozoites (MZ-2) and UO. In addition to the 58 kDa band, four other bands (~98 kDa, ~82 kDa, ~36 kDa and ~28 kDa) were detected in GAM. No bands were detected in MZ-3. Indirect immunofluorescence and immuno-electron microscopy localized EnSSB in the cytoplasm of macrogametocytes but not in wall-forming bodies and oocyst wall. Animal challenge experiments demonstrated that rEnSSB elicited robust IgY responses, increased splenic T lymphocytes and body weight gain, reduced intestinal lesion scores and oocyst shedding, and presented anticoccidial index (ACI) more than 160. These findings not only offer a foundation for understanding the role of EnSSB protein in regulating the development of E. necatrix, but also present a potential protective antigen of E. necatrix for the development of a subunit vaccine against avian coccidiosis. Full article

:Solvents represent the quiet majority in biomolecular systems, yet modeling their influence with both speed and ri:gor remains a central challenge. This study maps the state of the art in implicit solvent theory and practice, spanning classical continuum electrostatics (PB/GB; DelPhi, APBS), modern nonpolar and cavity/dispersion treatments, and quantum–continuum models (PCM, COSMO/COSMO-RS, SMx/SMD). We highlight where these methods excel and where they falter, namely, around ion specificity, heterogeneous interfaces, entropic effects, and parameter sensitivity. We then spotlight two fast-moving frontiers that raise both accuracy and throughput: machine learning-augmented approaches that serve as PB-accurate surrogates, learn solvent-averaged potentials for MD, or supply residual corrections to GB/PB baselines, and quantum-centric workflows that couple continuum solvation methods, such as IEF-PCM, to sampling on real quantum hardware, pointing toward realistic solution-phase electronic structures at emerging scales. Applications across protein–ligand binding, nucleic acids, and intrinsically disordered proteins illustrate how implicit models enable rapid hypothesis testing, large design sweeps, and long-time sampling. Our perspective argues for hybridization as a best practice, meaning continuum cores refined by improved physics, such as multipolar water, ML correctors with uncertainty quantification and active learning, and quantum–continuum modules for chemically demanding steps. Full article

Sulforaphane (SFN) is a bioactive compound belonging to the isothiocyanate family, known for its neuroprotective properties. While transcriptomic studies have highlighted SFN’s role in regulating gene expression, its impact on alternative splicing (AS), a key regulatory mechanism in neuronal metabolism, remains underexplored. In this study, we investigated whether SFN pre-treatment influences mRNA splicing patterns in an in vitro neuronal model using retinoic acid (RA)-differentiated SH-SY5Y cells. Using a dedicated RNA-seq-based splicing analysis pipeline, we identified 194 differential alternative splicing events (DASEs) associated with SFN treatment. Gene Ontology enrichment revealed significant over-representation of DNA repair processes. To better understand the functional implications, we integrated in silico predictions of premature stop codons, DASE/miRNA hybridizations, and DASE/RNA-binding protein (RBP) motif occurrences. Our findings suggest that SFN may modulate splicing of key DNA repair genes, contributing to protecting neurons against DNA damage. These preliminary results underscore a novel layer of SFN’s molecular effects and propose it as a valuable adjuvant in physiological conditions to enhance cellular health. Further studies are warranted to dissect the mechanistic underpinnings of SFN-mediated AS and its relevance in DNA-damage-related disorders. Full article

Drought stress poses a significant threat to tree growth, making the development of drought-resistant species essential for ecological restoration. WRKY transcription factors are critical regulators of plant drought responses; however, the role of WRKY22 in the woody species Populus ussuriensis K. remains unclear. In this study, the PuWRKY22 gene was cloned from P. ussuriensis via homologous cloning and was found to be highly expressed in leaves and responsive to abscisic acid (ABA) signaling. Subcellular localization confirmed that PuWRKY22 is a nuclear protein. Using fluorescein enzyme complementation assays, PuWRKY22 was shown to bind specifically to W-box cis-elements, indicating its function as a transcriptional regulator. Under ABA and osmotic (sorbitol) stress, the seed germination rate, root growth, and biomass of tobacco and Populus davidiana × Populus bolleana strains overexpressing PuWRKY22 were significantly increased. Additionally, these overexpressed strains exhibited a reduction in reactive oxygen species (ROS) accumulation and a decrease in membrane lipid peroxidation. Transcriptomic analyses revealed that PuWRKY22 activates expression of the ABA receptor gene Ptr.PYL4 (Potri.006G104100.v4.1), which regulates stomatal closure to minimize water loss. Consistent with this, stomatal observations and photosynthetic measurements demonstrated that PuWRKY22 enhances drought tolerance by protecting photosystem II and preserving chlorophyll content. Collectively, this study elucidates the molecular mechanism by which PuWRKY22 enhances drought resistance in woody plants through ABA signaling, providing a foundation for breeding drought-tolerant forest species. Full article