Novel Gemini surfactant-polyglutamic acid composite system enhances DNA delivery via a "Dual-Engine" uptake strategy.

Vascular endothelial growth factor receptor interacts with AP2-σ2 subunit to mediate the internalization of Vibrio parahaemolyticus into Eriocheir sinensis hemocytes.

Proteomics and metabolomics biomarkers for predicting the onset and progression of diabetic complications: A systematic review and bioinformatics integration.

This review comprehensively summarizes the interaction mechanisms between Megalin and several key ligands, including calcium ions, gentamicin, ApoE, ANKRA2, FVIII, TTR, STC1, RAP, and MMP-9, focusing on the specific amino acid binding sites involved. The analysis highlights the structural basis of these interactions and their clinical relevance, particularly concerning diseases such as nephrotoxicity, Alzheimer's disease, metabolic disorders, and renal pathologies. This review comprehensively summarizes the specific binding sites of Megalin with its ligands and explores the mechanisms, including protein reabsorption, blood coagulation, and neuroprotection, by integrating the results of animal studies and human clinical studies. This review proposes a theoretical framework for designing therapeutic strategies that target the binding sites of Megalin with its ligands. Gene editing technology and monoclonal antibody therapy aim to regulate Megalin receptor-ligand interactions to achieve therapeutic effects on related diseases.

Conformational dynamics study of TfR1 upon transferrin binding via NMA and MD simulations.

Abstract T cells are critically important to many diseases but are traditionally difficult to transfect. We hypothesise that the delivery of therapeutic cargo to T cells can be improved by targeting nanoparticles to surface receptors that undergo rapid receptor-mediated endocytosis. Using an internalisation assay that labelled intracellular and surface proteins with different fluorophores, we find that CD2 and CD7 exhibit significantly higher internalisation than other T cell receptors, such as CD3 or CD4. Targeting CD2 and CD7 improves nanoparticle internalisation by non-stimulated, primary CD4 + T cells and enhances the specificity of association to CD4 + T cells. Similarly, functionalising mRNA-lipid nanoparticles with antibodies targeting CD2 or CD7 enhances mRNA delivery to CD4 + T cells in vitro. Importantly, targeting CD2 or CD7 enables efficient lipid nanoparticle-mediated delivery of mRNA to T cells in blood and lymphoid tissue in vivo, demonstrating that targeting T cell receptor endocytosis can enhance nanoparticle-mediated drug delivery to T cells.

Size- and morphology-dependent cytotoxicity of metal-organic frameworks: Deciphering the structure-toxicity relationship.

Traumatic brain injury (TBI) remains a leading cause of death and disability worldwide in intensive care units, yet no targeted neuroprotective therapies exist despite over 300 clinical trials. This therapeutic failure stems partly from biological heterogeneity and the limitations of single-biomarker approaches that cannot capture the multifaceted pathophysiology of secondary brain injury. Systems biology approaches examining dysregulated pathways rather than isolated proteins may reveal candidate endotypes suitable for patient stratification and identify potential therapeutic targets. We conducted an exploratory, case-control study, in adult critically-ill patients comparing 10 severe TBI (sTBI) patients (median GCS 5.5) with 10 age-and sex-matched healthy controls. Plasma samples were collected upon admission to the ICU, within 24h of injury. High-throughput proximity extension assays quantified 1196 plasma proteins, identifying multiple differentially expressed proteins. Gene set enrichment analysis interrogated Reactome pathways and Gene Ontology terms. Protein-protein interaction networks were constructed using the STRING database, and associations between enriched pathways and clinical variables were examined. We identified 348 significantly differentially abundant proteins between groups. Gene set enrichment analysis revealed 19 enriched Reactome pathways and 12 Gene Ontology terms, predominantly reflecting immune activation, inflammation, cellular stress responses, and intracellular trafficking. Strikingly, membrane trafficking pathways, including clathrin-mediated endocytosis and Golgi transport, emerged as significantly enriched, representing an underrecognized mechanism in sTBI pathophysiology. Protein-protein interaction analysis identified four functional clusters, with IL6 and IL10 as densely connected hub proteins coordinating inflammatory responses. Membrane trafficking pathways were associated with clinical outcomes including both length of hospital and intensive care unit stay, as well as need for neurosurgical intervention, in sTBI patients. By profiling the expression of 1196 plasma proteins in parallel, this study provides one of the most comprehensive proteomic characterizations of critically-ill adults with severe traumatic brain injury to date. Systems biology analyses suggest that sTBI may trigger coordinated pathway-level dysregulation extending beyond inflammation to include subcellular trafficking machinery. The association between membrane trafficking pathways and clinical outcomes suggests these may represent a candidate molecular endotype with prognostic relevance. These hypothesis-generating findings support pathway-based approaches for patient stratification and therapeutic targeting in sTBI, though validation in larger cohorts is required.

Accelerated CHRN/AChR/nicotinic acetylcholine receptor internalization induced by auto-antibodies impairs neuromuscular junction transmission and contributes to myasthenia gravis (MG), a typical autoimmune disease. Although CHRN internalization is well established in MG pathogenesis, the downstream cellular events, especially those related to autophagy, remain poorly described. Here, we report that RAPSN/rapsyn, an intracellular CHRN-binding protein essential for its clustering, accumulates as aggregates in experimental autoimmune myasthenia gravis (EAMG) mice. In CHRN antibody-treated myotubes, RAPSN dissociates from internalized CHRN and forms aggregates due to exposure of its hydrophobic domains. These aggregates in turn impair the trafficking and membrane incorporation of newly synthesized CHRN, thereby exacerbating CHRN loss. Notably, the accumulation of RAPSN aggregates facilitates formation of HSPA/HSP70-BAG3 complex, which recognizes and transports the aggregates along microtubules to form perinuclear aggresomes for subsequent lysosomal degradation. Accordingly, pharmacological inhibition or knockdown of HSPA-BAG3 complex increases RAPSN aggregation, which participates in enhanced CHRN loss and worsened muscle weakness in EAMG mice. This study identifies HSPA-BAG3 aggrephagy as a protective mechanism that clears RAPSN aggregates to maintain CHRN integrity and suggests a potential therapeutic strategy for MG.Abbreviation: 3-MA: 3-methyladenine; AAV: adeno-associated virus; CASA: chaperone-assisted selective autophagy; CHRN/nicotinic acetylcholine receptor: cholinergic receptor nicotinic; CHRN-ab: CHRN antibodies; CHX: cycloheximide; CMAP: compound muscle action potential; CQ: chloroquine; EAMG: experimental autoimmune myasthenia gravis; ER: endoplasmic reticulum; GAS: gastrocnemius; MAP1LC3A/B: microtubule associated protein 1 light chain 3 alpha/beta; MG: myasthenia gravis; NMJ: neuromuscular junction; Rapa: rapamycin; RAPSN/rapsyn: receptor associated protein of the synapse; SQSTM1: sequestosome 1; TA: tibialis anterior; αBTX-A594: α-bungarotoxin-Alexa-594.

Apolipoprotein E in Alzheimer's disease: A review of APOE receptors, signalling pathways and therapeutic opportunities.

Rice has developed an efficient system for manganese (Mn) uptake, mediated by two distinct transporters, OsNramp5 and OsMTP9. These transporters exhibit polar localization at the root exodermis and endodermis; however, the mechanisms underlying their polar localization and their role in Mn uptake remain unclear. Here, we identified key amino acid residues critical for the polar localization of OsNramp5 at the distal side. Through analysis of chimeric proteins between OsNramp5 and its non-polar homologues, we found that the C-terminal cytosolic region of OsNramp5 is essential for its polar localization. Site-directed mutagenesis further revealed that aspartate 500 and four valine residues at positions 494, 495, 498 and 506 are crucial for polarity. Substitution of these valine residues with isoleucine, leucine, phenylalanine, or threonine partially or fully maintained polar localization, whereas substitution with alanine, serine, or asparagine resulted in loss of polarity. These findings suggest that β-branching and high hydrophobicity of amino acid side chains are likely required for OsNramp5 polarity. Furthermore, we found that adaptor protein 2-dependent clathrin-mediated endocytosis is not involved in the polar localization of OsNramp5. Finally, we provided experimental evidence showing the significant role of OsNramp5 polarity in efficient Mn uptake in rice; plants expressing non-polarly localized OsNramp5 exhibited reduced Mn uptake compared to those with polarly localized OsNramp5. In addition, we found that cadmium accumulation in shoots could be reduced by manipulating OsNramp5 polarity in combination with its overexpression, without a growth penalty.

Convergent imaging and genetic signatures of gray matter atrophy in Parkinson's disease.

pH-responsive folate-targeted catalase conjugate for enhanced cellular uptake and oxidative stress protection in triple-negative breast cancer.

Donnai-Barrow syndrome (DBS) arises from loss-of-function (LoF) variants in the endocytic receptor low-density lipoprotein receptor-related protein 2 (LRP2; or megalin) and is characterized by low-molecular weight proteinuria and developmental abnormalities. Urinary proteomics of 9 patients with DBS revealed that the urinary proteome of a DBS patient with the missense variant LRP2 p.C1400R was indistinguishable from that of patients with splice site, nonsense, or frameshift mutations. A CRISPR mouse model of the variant was generated to determine the mechanism of LoF and proteinuria. The mutant LRP2 was expressed and observed to dimerize and localize to the proximal tubule apical membrane. However, both fluid-phase and receptor-mediated endocytosis was impaired in the context of a general perturbation of endocytic flux. Immunofluorescence revealed aberrant endocytic recycling with mislocalized RAB11+ and TFR1+ compartments and enlarged lysosomes. Structural modeling showed that the LRP2 assembly likely tolerates the cysteine-to-arginine substitution at the cell surface, but at endosomal pH the variant introduced steric clashes that may disrupt intramolecular interfaces and disturb receptor recycling. These findings point to the importance of LRP2 recycling for global endocytic flux and offer a blueprint for leveraging patient-specific alleles to dissect proximal tubule function.

Cataract remains the most prevalent cause of visual impairment and irreversible blindness worldwide. It is characterized by lens opacification arising from crystallin denaturation, leading to variable degrees of vision loss and poor quality of life. Although crystallin denaturation is the primary pathological basis of cataract, oxidative stress and inflammation also play significant roles. It was first confirmed that nattokinase (NK) could degrade cataractous tissue and alleviate the opacification using human cataract phacoemulsification fluid, thus supporting the in vivo anti-cataract efficacy of NK-based nanocomposites (NNs). Herein, we developed minimalist NNs as eye drops, through electrostatic self-assembly between NK and natural macromolecules. The NNs exert three-pronged therapeutic effects (antioxidant, anti-inflammatory, and anti-crystallin denaturation) that disrupt the pathological cycle in cataract. The in vitro cellular studies demonstrated that the NNs were internalized via receptor-mediated endocytosis and micropinocytosis, and efficiently achieved a synergistic scavenging effect of reactive oxygen species (ROS). In ultraviolet B (UVB)-induced cataract mice, the NNs successfully suppressed oxidative stress and inflammation, while protecting crystallins through enhanced intracorneal retention, ultimately ameliorating lens opacity index. Moreover, further analysis revealed that NNs effectively inhibited ROS accumulation by up to 15.78-fold, along with the ROS/NLRP3/pyroptosis axis and the denaturation of crystallins, thereby offering new insights into therapeutic regimens for cataract. Consequently, the NNs alleviated lens opacification by breaking the cataract vicious cycle through a three-pronged inhibition of oxidative stress, inflammation, and crystallin denaturation. Our findings pave the way for utilizing NNs as a novel strategy for reversing cataract, as well as associated ocular disorders.

Amivantamab induces immune-mediated cytotoxicity in mesothelioma via EGFR and MET engagement.

OptoH3R is an artificial fusion protein that combines the photosensitive elements of rhodopsin with the signaling domain of the histamine H3 receptor (H3R), enabling light-controlled activation of downstream H3R pathways. Although our previous study demonstrated that OptoH3R mimics the acute effects of H3R activation on neuronal activity, whether this tool can also recapitulate the long-term receptor desensitization and internalization processes associated with prolonged H3R activation remains unclear. In this study, primary cortical neurons and HeLa cells were employed to investigate the alterations in subcellular localization of OptoH3R upon sustained photoactivation, with histamine-stimulated wild-type (WT) H3R serving as a control. Furthermore, the role of β-arrestin in this process was explored. Time-lapse fluorescence imaging revealed that the number of puncta progressively increased over time following laser stimulation. Subsequent co-staining experiments with endosome marker EEA1 showed that 75.5% of light‑induced puncta were EEA1‑positive. Notably, the increase in OptoH3R-positive vesicles within neuronal cells was attenuated by the β-arrestin inhibitor barbadin, a pattern consistent with the internalization observed in histamine-stimulated WT H3R. Collectively, our findings demonstrate that OptoH3R recruits β-arrestin signaling upon sustained optical stimulation, thereby recapitulating H3R desensitization dynamics. This establishes OptoH3R as a useful tool for dissecting the spatiotemporally specific functions of H3R, including both its acute signaling and long-term β-arrestin-related mechanisms.

Cytotoxicity of silica micro/nano particles with amine surface modifications to 6-3 murine microglial cell line.

ABSTRACT Bovine coronavirus (BCoV) is an important pathogen that exhibits dual tropism for the respiratory and intestinal tracts, causing winter dysentery in adult cattle, diarrhea and respiratory infections in calves, thus imposing considerable economic losses on the global cattle industry. Our previous studies demonstrated that BCoV gains entry into susceptible HRT-18 cells through membrane fusion and clathrin-mediated endocytosis (CME). However, the precise mechanisms by which BCoV enters host cells remain incompletely elucidated, particularly in primary bovine intestinal epithelial cells (PBIECs). Importantly, as primary cells derived from the natural host, PBIECs more closely recapitulate the in vivo infection microenvironment than HRT-18 cell lines. In the present study, chemical inhibitors, RNA interference, and fluorescently labeled BCoV particles were used to define distinct entry pathways. Our data demonstrated that BCoV enters PBIECs via membrane fusion and three distinct endocytic pathways, including CME, caveolin-mediated endocytosis (CavME), and macropinocytosis. Dynamin, microtubules, cathepsins, and an acidic environment are essential for mediating endocytic entry, whereas cholesterol and TMPRSS2 are dispensable for this process. Furthermore, targeted interference with Rab5, Rab7, and Rab11 suppressed BCoV entry into PBIECs. Consistently, co-localization of fluorescently labeled BCoV with Rab5, Rab7, and Rab11 was observed by confocal microscopy, indicating that these Rab GTPases are involved in BCoV entry into PBIECs. These findings elucidate the entry mechanisms of BCoV and provide novel perspectives to enhance a more comprehensive understanding of the BCoV life cycle.

AMPA receptors, members of the ionotropic glutamate receptor family, are the principal mediators of fast excitatory synaptic transmission in the brain, and their trafficking to and from synapses is critical for neuronal communication. AMPA receptor trafficking is primarily regulated by posttranslational modifications. These receptors undergo diverse site-specific posttranslational modifications, including phosphorylation, palmitoylation, ubiquitination, S-nitrosylation, N-glycosylation, O-GlcNAcylation, and SUMOylation. Crosstalk among these modifications further adds to the complexity of AMPA receptor regulation. Accumulating evidence indicates that posttranslational modifications not only govern receptor trafficking and synaptic retention but also regulate synaptic strength during both Hebbian and non-Hebbian forms of synaptic plasticity, as well as memory function. Long-term potentiation induces site-specific modifications that promote synaptic incorporation of AMPA receptors, whereas long-term depression is associated with modifications that drive receptor internalization. Mutations affecting posttranslational modification sites disrupt AMPA receptor trafficking, impair synaptic plasticity, and alter memory function. Moreover, aberrant regulation of AMPA receptor posttranslational modifications has been linked to memory dysfunction during aging and in several neurological disorders. This review summarizes current understanding of how posttranslational modifications of AMPA receptors regulate synaptic plasticity, contribute to memory function, and are implicated in cognitive decline in aging and in disorders such as Alzheimer's disease and schizophrenia.