Biology subjects

Yu, Y.

Publications and source records attributed to Yu, Y..

At least 73 records · Page 4Linked to original sources

bioRxiv2026

A Time-Sequenced Three-Drug-Loaded Microneedle Patch for the Prevention of Vein Graft Restenosis After Coronary Artery Bypass Grafting

Coronary artery bypass grafting (CABG) is the recommended treatment for severe coronary heart disease; however, restenosis of great saphenous vein grafts continues to limit long-term outcomes because of early thrombosis, mid-term intimal hyperplasia, and late atherosclerosis. To address these sequential pathological processes, this study develops a perivascular drug-loaded microneedle (MN) patch capable of controlled chronological release of tirofiban, rapamycin, and rosuvastatin. The MN patch exhibits uniform conical microneedles (height: 700-800 {micro}m), nanoparticle size of 125 nm, sufficient mechanical strength (1.07 N/needle) for venous intimal penetration, excellent biocompatibility, and no detectable cytotoxicity or hemolysis. In a mouse model of venous graft transplantation, the device significantly reduces early platelet thrombus formation (23.3% to 10%), alleviates mid-term intimal hyperplasia (intimal thickness: 0.84 mm to 0.45 mm at 4 weeks), and improves long-term graft patency with blood flow increasing from 13.1 to 65.8 mL/min at 32 weeks while reducing long-term mortality. Mechanistically, RNA sequencing and functional analyses demonstrate that excessive glycolysis-driven smooth muscle cell proliferation, coupled with abnormal endothelial cell apoptosis, constitutes the core mechanism underlying mid- to long-term restenosis, which the MN device effectively suppresses. This integrated MN patch provides a localised therapeutic strategy for preventing restenosis and improving long-term CABG outcomes. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=151 SRC="FIGDIR/small/726718v1_ufig1.gif" ALT="Figure 1"> View larger version (63K): org.highwire.dtl.DTLVardef@1de0e6borg.highwire.dtl.DTLVardef@184a846org.highwire.dtl.DTLVardef@43a50forg.highwire.dtl.DTLVardef@109bb85_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2026

Further evidence of much higher covariation with saccadic reaction time of superior colliculus than primary visual cortex visual responses

Visual response strength in the primate superior colliculus (SC) has recently been shown to inversely correlate with trial-by-trial saccadic reaction time in a much stronger way than visual response strength in the primary visual cortex (V1). However, for any given visual stimulus onset, populations of neurons in each brain area are concurrently activated, leaving open the question of how V1 visual response strength can predict trial-by-trial saccadic reaction time when multiple simultaneously recorded neurons are taken into account. Using a classic visually-guided saccade task, here we assessed the quality of predicting trial-by-trial saccadic reaction time from the visual response strengths of 1 to 10 simultaneously recorded neurons in each brain area. For each session, we modeled saccadic reaction time as a weighted linear combination of the visual response strengths of N simultaneously recorded neurons. Consistent with the prior work, the visual response strength of a single SC neuron was better than that of a single V1 neuron at predicting reaction time. By adding more simultaneously recorded neurons, the prediction got much better in the SC, but not in V1. Only for 100% contrast dark stimuli (darker in luminance than the surrounding gray background) did V1 show an increase in prediction quality with more simultaneously recorded neurons. This increase, which was still substantially weaker than in the SC, could reflect the ecological relevance of dark contrasts in scenes. These results suggest that despite qualitative similarities between SC and V1 visual responses, SC visual responses are functionally reformatted from their V1 counterparts. SignificanceThe superior colliculus (SC) is an important sensory-motor structure for controlling eye movements, and it receives a significant portion of its inputs directly from the primary visual cortex (V1). Despite this, SC visual responses are much better correlated with trial-by-trial variability in saccadic eye movement timing than V1 visual responses, and this effect is strongly amplified when considering simultaneously recorded neurons. Thus, SC and V1 visual responses serve fundamentally different functions from a motor perspective.

neuroscience↗

bioRxiv2026

Mapping the interactome of human tRNA methyltransferase TRMT1 using dual proximity labeling

Transfer RNA methyltransferase 1 (TRMT1) installs N2-methylguanosine and N2,N2-dimethylguanosine modifications at position 26 of mammalian tRNAs, supporting tRNA structure, translation, and cellular response to redox stress. However, the local environment and interactome of TRMT1 in the cell is poorly defined. Here, we use APEX2-based proximity labeling of the N- and C-terminus of TRMT1, coupled with label-free quantitative proteomics to map candidate TRMT1-proximal proteins in HEK293T cells. Mass spectrometry data was acquired using both data-independent acquisition (DIA) and data-dependent acquisition (DDA) methods, and it was found that DIA substantially increased proximity proteome coverage, reproducibility, and the number of significantly enriched candidate hits compared to the DDA method. N- and C-terminal APEX2-TRMT1 constructs captured largely overlapping proteomes, suggesting the dual-labeling strategy provides a robust map of proximal proteins. Analysis of the significant TRMT1-proximal proteins reveals enrichment in RNA processing and ribonucleoprotein-associated factors, in addition to hits connected to tRNA modification, tRNA biogenesis, and redox-associated biology. These data provide a proteome-scale view of TRMT1-associated cellular proteins and environments, and lay the groundwork for future validation of functional TRMT1 interaction networks. SignificanceO_LIFusing APEX2 enzyme to both N-terminal and C-terminal of the bait enhanced the sensitivity for identification of protein interactions. C_LIO_LICombining APEX2-based endogenous labeling with DIA mass spectrometry increases reproducibility and depth of proximity proteome. C_LIO_LIThe study provides a rich source of potential interacting or proximally close proteins to TRMT1, which warrants further validation studies. C_LI

biochemistry↗

bioRxiv2026

FTO separation-of-function mutations alter m6A versus m6Am demethylation selectivity on RNA

The RNA demethylase FTO erases N6-methyladenosine (m6A) and cap-associated N6,2'-O-dimethyladenosine (m6Am) modifications. However, the molecular basis of its substrate selectivity and the biological effects of m6A versus m6Am demethylation in cells remain poorly understood. Here we report two engineered FTO separation-of-function mutants to selectively demethylate either m6A or m6Am modifications on RNA. While investigating the propensity of FTO active site residues to undergo self-hydroxylation, we found that mutations of FTO residue L203 resulted in impaired m6A demethylation but retained wild-type levels of m6Am demethylation, and that FTO L203A could function as a selective m6Am demethylase. Conversely, building on our recent work that identified conserved aromatic residues on FTO involved in mRNA 5' cap recognition, we found that the FTO H232A/W278A double mutant efficiently demethylates m6A modifications while exhibiting substantially impaired m6Am demethylation, making it a selective m6A demethylase. Together, these complementary FTO variants represent the first set of engineered mutations that shift FTO demethylation selectivity between m6A and m6Am substrates. These tools enable selective enzymatic removal of m6A or m6Am modifications in vitro for sequencing applications, and may facilitate understanding of FTO-mediated m6A versus m6Am demethylation in cellular and disease model systems.

biochemistry↗

bioRxiv2026

Thoughts-as-Planning: Latent World Models for Chain-of-Thoughts Optimization via Reinforcement Planning

The success of large language models (LLMs) across diverse NLP tasks has elevated the importance of reasoning chain optimization as a critical step in aligning model behavior with task objectives. Existing reasoning chain tuning methods often rely on black-box heuristics or gradient-free search, which lack interpretability, generalization, and sample efficiency. In this work, we introduce Thoughts-as-Planning, a novel framework that formalizes reasoning chain optimization as a sequential decision-making process over a latent semantic space. We model the LLM as a partially observable environment and learn a latent world model that simulates the effect of reasoning chain edits on downstream outputs. A proximity-preserving embedding space is constructed to encode reasoning chain-response dynamics, enabling planning via gradient descent or reinforcement learning. Our method supports multi-scale abstraction, allowing reasoning chain edits at token, segment, and instruction levels to be integrated into a unified planner. Through extensive experiments on language understanding and generation tasks, we demonstrate that Thoughts-as-Planning outperforms state-of-the-art reasoning chain tuning baselines in efficiency, robustness, and generalization, while offering interpretability through its structured planning trajectory. Our code is available at https://github.com/FastLM/Thoughts-as-Planning.

neuroscience↗

bioRxiv2026

A Cherry-Flavoured E-Cigarette Adduct, BPGA, Reprograms Alveolar Epithelial Cell Fate Through Epithelial-to-Mesenchymal Transition and Evasion of Apoptosis

E-cigarettes have attracted significant attention as a safer substitute for conventional tobacco smoking. However, they have introduced new inhalable toxicants, including benzaldehyde-propylene glycol acetal (BPGA)--a chemical adduct produced by cherry-flavoured e-cigarettes. The health risks associated with such flavour-derived acetals remain insufficiently elucidated at the cellular level. This study investigated the role of BPGA in the progression of epithelial-to-mesenchymal transition (EMT)-like changes in alveolar epithelial cells (A549 cells). A549 cells exposed to various concentrations of BPGA were analysed for cell viability, morphology, mitochondrial function, lysosomal health, and cytoskeletal integrity using viability assays and fluorescence imaging. Intracellular reactive oxygen species (ROS) production was quantified using the 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) assay. Antioxidant enzyme expression, inflammatory responses, and EMT-associated phenotypic alterations were evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunofluorescence (IF) assays. Exposure of alveolar epithelial cells to BPGA caused a concentration-dependent decrease in cell viability. BPGA exposure resulted in mitochondrial membrane depolarisation, lysosomal damage, cytoskeletal changes, and stress fibre formation, which altered cell morphology. It significantly increased intracellular ROS production. As a result, antioxidant enzyme levels were upregulated as a protective response. However, during severe oxidative stress, this response was overwhelmed. Excess ROS disrupted cellular homeostasis and initiated apoptosis, though not completely. ROS also acted as a signalling molecule, promoting the upregulation of inflammatory mediators. These changes were associated with altered EMT marker expression, suggesting that BPGA might drive EMT-like remodelling. In conclusion, BPGA, a chemical adduct from e-cigarette vapour, induces alveolar injury by promoting oxidative stress, inflammation, and EMT-related changes, which may explain a mechanism by which e-cigarette exposure could lead to lung injury and pulmonary fibrosis. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=169 SRC="FIGDIR/small/724520v1_ufig1.gif" ALT="Figure 1"> View larger version (60K): org.highwire.dtl.DTLVardef@2e9797org.highwire.dtl.DTLVardef@e2543eorg.highwire.dtl.DTLVardef@108bb1aorg.highwire.dtl.DTLVardef@33e710_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstractC_FLOATNO C_FIG

pharmacology and toxicology↗

bioRxiv2026

Large-Scale Assessment of NF1 Single Amino Acid Variants as HLA Class I Neoantigens

Neoantigens are cancer-specific antigens arising from genomic alterations. Single Amino Acid Variants (SAAVs) represent a primary class of these neoantigens. To evaluate the therapeutic potential of Neurofibromin 1 (NF1)-derived SAAVs - given that NF1 is frequently mutated in malignant brain tumors - we prioritized the 40 NF1 SAAVs determined to be HLA-A*02:01 binders using computational prediction coupled with experimental validation. To validate these predicted neoepitopes, we employed a two-tiered experimental approach in HLA-A*02:01 homozygous U87-MG cells. We first synthesized minigene constructs encoding the predicted neoepitopes, introduced them via lentiviral transfection and confirmed their expression by mass spectrometry (MS). Subsequently, we performed endogenous validation using pan-HLA immunoprecipitation mass spectrometry (IP-MS), confirming 4 (10 neoepitopes) of the 40 candidate SAAVs. We observed a discrepancy between in silico predictions and the observed sequences. Our endogenous peptidomics further revealed conserved peptide motifs and demonstrated that peptide selection for HLA presentation is transient. While our study substantiates the therapeutic feasibility of T-cell immunotherapies targeting NF1 mutations, these results underscore a limitation in current computational prediction. Our study highlights the necessity of experimental validation to refine neoantigen prioritization strategies.

immunology↗

bioRxiv2026

Humanization of N-glycan-dependent protein quality control system in Kluyveromyces marxianus promotes glycoprotein secretion

Human N-glycoproteins constitute a market worth hundreds of billions of dollars. However, their production in yeast is often limited by misfolding and subsequent degradation, largely due to differences in N-glycan-dependent protein quality control (QC) systems between humans and yeast. Notably, yeast lacks the UGGT-mediated reglucosylation-refolding cycle that rescues misfolded glycoproteins, and its degradation pathway involves fewer rate-limiting steps. To address this, we engineer the glycoprotein QC system in Kluyveromyces marxianus, a promising host for protein production, by introducing key human components and modifying native pathways. Expression of human UGGT1 or UGGT2 enhances the soluble and secretory production of glycoproteins in an activity-dependent manner. This effect is further improved by co-expression of the UGGT cochaperone SEP15 and by reducing native glucosidase II trimming activity. In addition, introduction of human EDEM2, a rate-limiting enzyme in glycoprotein degradation, delays ER-associated degradation and increases secretion. Integration of these engineering strategies substantially enhances the production of several high-value human-derived glycoprotein therapeutics, including etanercept, dulaglutide, and abatacept, with up to a [~]12-fold increase. These findings demonstrate that engineering a human-like glycoprotein QC network in yeast is an effective strategy to improve glycoprotein folding and secretion.

bioengineering↗

bioRxiv2026

Multimodal profiling reveals the centromedian nucleus of thalamus as a dynamic hub orchestrating staged consciousness recovery

Consciousness recovery from general anesthesia represents a fundamental brain state transition. The absence of objective, continuous metrics to monitor the shift from unconsciousness to full awareness has left its dynamic, multidimensional nature unresolved, fracturing consciousness theoretical framework and posing clinical risks due to unreliable assessment of emergence. To address this, we developed a multiscale framework integrating AI-driven behavioral analysis, continuous neuro-physiology recording, and whole-brain functional imaging. This decodes recovery into three hierarchical stages, reflex restitution, level restoration, and content re-establishment, each with unique multimodal signatures. We identified heart rate stabilization as a potential noninvasive biomarker for the restoration of consciousness level. Crucially, the centromedian nucleus of thalamus acts as a dynamic hub, actively orchestrating staged whole-brain reconfiguration via stage-dependent network routing. These findings resolve the temporal orchestration of consciousness recovery, ground disparate theories within a unified mechanistic sequence, and open transformative paths for real-time monitoring and neuromodulation in anesthesiology. HighlightsA multimodal framework decodes consciousness recovery into three hierarchical stages Recovery stages span from reflex restitution, to level restoration, and finally to content re-establishment Heart rate stabilization serves as a noninvasive biomarker for consciousness level restoration The CM paces this staged reconfiguration as a dynamic network hub In BriefZhang et al. develop a multiscale framework that delineates consciousness recovery from anesthesia as a three-stage process, identifies heart rate stabilization as a biomarker for the restoration of consciousness level, and reveals the CM as a dynamic hub orchestrating this progression. These findings clarify the temporal orchestration of consciousness recovery, pave the way for real-time monitoring and neuromodulation in anesthesiology and other fields.

neuroscience↗

bioRxiv2026

A dataset of simultaneous two-photon calcium imaging and auditory discrimination behavior

The emerging field of artificial intelligence for neuroscience relies heavily on high-quality, standardized datasets. Data linking high-dimensional neural population dynamics with complex behavior is crucial for advancing the field of brain-computer interfaces. However, few existing datasets provide these paired modalities in a standardized, AI-ready format, limiting their immediate utility for computational modeling. Here, we present a large-scale dataset comprising simultaneous two-photon calcium imaging of the primary auditory cortex (A1) and detailed behavioral records in mice. The animals performed an auditory two-alternative forced-choice (2AFC) categorization task, classifying tones as low or high frequency by licking left or right water ports. The raw neural and behavioral data were preprocessed, synchronized, and formatted into trial-aligned multi-dimensional tensors. Comprehensive validation confirms that the recorded populations exhibit consistent, high-fidelity temporal dynamics and distinct frequency tuning across all experimental conditions. To evaluate the datasets capacity for neural decoding, we benchmarked it across diverse machine learning architectures and deep learning networks. By bridging biological recordings and behavior, this open-access dataset serves as a valuable benchmark for developing novel decoding algorithms and testing brain-inspired computational models.

neuroscience↗

bioRxiv2026

Holomycin from Yersinia ruckeri mediates fish infection at low temperature

Why microbes invest energy in producing structurally complex natural products at extremely low concentrations within hosts remains an important topic of interest in microbial ecology. This is because such compounds with potential "biomolecular activities" can reflect molecule-target interactions, thereby providing conceptual and mechanistic insights that inform the rational design of essential clinical agents. Here, we uncover the in situ ecological function of the dithiolopyrrolone antibiotic holomycin produced by the fish pathogen Yersinia ruckeri. We show that holomycins biosynthesis is strictly gated by low temperature and that trace amounts of holomycin accumulate in vivo during infection in rainbow trout. In addition, the holomycin-deficient mutant leads to markedly reduced virulence. Integrated multiomics, phenotypic analyses, and in vivo bioassay test reveal that holomycin is not a direct lethal factor but instead remodels host-associated microbiota and enhances Y. ruckeri biofilm formation. These coordinated effects promote pathogen colonization and infection progression. Our findings establish holomycin as a host-associated effector and illustrate how its existence and ecological function are mechanistically intertwined in the evolution of pathogenic bacterial chemical arsenals.

microbiology↗

bioRxiv2026

Laccase-mediated biotransformation potential for fluorinated compounds by geographically diverse human gut microbiota

The growing prevalence of synthetic organofluorine substances in agrochemicals, food packaging, and consumer products has led to increasing gastrointestinal exposure, with potential consequences for human health. Despite the extreme stability of fluorinated compounds, several microbial pathways for their transformation are known, including by laccases, a type of multicopper oxidase. However, the functionality of laccases in the gut microbiome, a natural contact point between food-associated chemicals and microbial biotransformation pathways, is poorly defined. Through a multi-study analysis of 1578 human gut metagenomes spanning a global gradient from hunter-gatherer societies to industrialized urban populations, we found that laccase-coding gene homologs are widely distributed in the human gut microbiome. We identified a significant association between both the abundance and phylogenetic diversity of laccase homologs with the degree of urbanization. As human gut microbial laccase activity has not been experimentally demonstrated, eight gut metagenome-derived laccases were heterologously expressed and screened for activity with a redox mediator system. Six of the eight laccases demonstrated activity. One of these gut microbial laccases and three previously characterized laccases were then tested for their capacity to deplete 11 different food-associated chemicals. All four effectively depleted the agrochemicals cyflumetofen and fluazinam, as well as the industrial chemical bisphenol AF to a lesser extent. By linking global gut metagenomes with activity assays, this work demonstrates the untapped potential of mining human gut metagenomes for laccases and other microbial enzymes that can actively modify various agricultural and industrial chemicals. ImportanceAs adverse effects of fluorinated compounds on human health are emerging, the responsible enzymes from the human gut microbiome of geographically diverse human cohorts mediating interactions with fluorinated compounds in the gastrointestinal tract remain poorly characterized. In a multi-study analysis of publicly available microbiome sequencing data, we linked the abundance, diversity, and phylogeny of laccases within the gut microbiome to the degree of urbanization of human cohorts, and experimentally demonstrated the ability of these laccases to deplete a range of food-associated fluorochemicals. Another significant contribution of our study is in the integration of rural catchment areas as a quantitative metric of urbanization in gut microbiome metagenomics and enzyme activity surveys.

microbiology↗

bioRxiv2026

Therapeutic Potential of Hypoxia-Preconditioned hiPSC-Epicardial Cell-Derived Exosomes in Mice with Myocardial Infarction

BackgroundIt has been demonstrated that stem cell transplantation promotes healing of the infarcted heart through paracrine effects. However, the therapeutic potential of exosomes secreted by hiPSC-derived epicardial cells (hEP-Exos) for treating infarcted hearts remains unclear. Myocardial infarction (MI) can trigger EP activation, increasing EP paracrine function. Therefore, this study aims to determine and compare the cardioprotective effects of exosomes secreted by hEPs under normoxic (Exo-N) and hypoxic (Exo-H) conditions in MI mice and to explore the underlying mechanisms. MethodsTwo types of exosomes were collected by ultracentrifugation and delivered via intramyocardial injection in a murine MI model. The protective effects of Exo-N and Exo-H on the infarcted heart were assessed using echocardiography, histological examination, and immunofluorescence analysis. Additionally, microRNA sequencing, luciferase activity assays, and miRNA gain-and loss-of-function experiments were performed to identify enriched miRNAs and investigate their roles in different exosome populations. ResultsIn vitro, both Exo-N and Exo-H enhanced the migration and tube-formation capacities in human umbilical vein endothelial cells (HUVECs) and reduced the apoptosis in hiPSC-derived cardiomyocytes (hCMs) under oxygen-glucose deprivation (OGD), with Exo-H exhibiting a stronger effect. In vivo, both Exo-N and Exo-H significantly improved contractile function, reduced infarct size, and mitigated adverse remodeling in mouse hearts with MI, accompanied by increased cardiomyocyte survival and angiogenesis, with Exo-H showing superior efficacy. Mechanistically, miRNA sequencing revealed distinct cargo profiles between Exo-N and Exo-H. miR-214-3p was identified as a key mediator of the enhanced therapeutic potency of Exo-H. miR-214-3p promoted EC angiogenesis by suppressing vasohibin-1 and attenuated cardiomyocyte mitochondrial fission and apoptosis by suppressing mitochondrial elongation factor 2 (MIEF2). ConclusionsThis study demonstrates that administration of hEP-Exos, particularly Exo-H, provides robust cardioprotection by enhancing cardiomyocyte survival and angiogenesis, potentially mediated by miR-214-3p. These findings suggest that conditioned hEP-Exos could be a promising and effective acellular therapeutic option for treating MI.

cell biology↗

bioRxiv2026

Expectation triggers a change-like EEG response without acoustic change

Predictive processing theories posit that the auditory system continuously generates expectations and updates internal models when incoming evidence violates those expectations. Whether such updating can be expressed as a temporally precise, change-like neural response at a context-defined moment during continuous stimulation--without any physical change--has remained unclear. Using a transitional click-train paradigm in human EEG, we show that listeners reliably detect subtle midpoint transitions when click timing is fixed, whereas temporal uncertainty markedly weakens this sensory-driven detection. Strikingly, even in a physically unchanged stimulus, variable click timing elicits a robust response time-locked to the nominal midpoint. This endogenous change-like signal is stimulus-statistics dependent--absent in the fixed-timing no-change control--temporally confined to the early post-change window, and strongly state dependent, being amplified during active change detection relative to passive listening. Moreover, within identical no-change trials, the response tracks subjective change reports. Together, these findings show that temporal uncertainty and task engagement jointly gate predictive updating in continuous auditory streams, providing a compact assay to dissociate sensory-driven change responses from context- and state-dependent predictive signals.

neuroscience↗

bioRxiv2026

Microbiota-induced fatty acid synthesis facilitates intestinal infection and immune-mediated damage in Drosophila

The role of the microbiota in facilitating infection is increasingly recognized, though the underlying mechanisms remain under investigation. In this study, we demonstrate that the gut microbiome, particularly Lactiplantibacillus plantarum, promotes enteric infection in Drosophila melanogaster by reshaping host physiology and immune responses. Upon gut colonization, L. plantarum enhances fatty acid (FA) production in the gut. Reducing FA synthesis improves host survival, and pathogen mutants deficient in FA utilization exhibit reduced virulence. FAs support pathogen growth, increase virulence, and enhance resistance to antimicrobial effectors, ultimately facilitating pathogen persistence in the gut. Persisting pathogens consequently overstimulate the immune system, leading to excessive production of antimicrobial peptides (AMPs). Flies lacking AMPs, particularly Metchnikowin and Attacin D mutants, show better survival during infection, implicating AMPs in immunopathology. Our findings identify a mechanism whereby microbiota-induced release of host FAs stimulates pathogen virulence and persistence, ultimately driving AMP-mediated immunopathology.

microbiology↗

bioRxiv2026

The native structure of the Trichonympha centriole cartwheel reveals a zigzag stacking pattern

Centrioles are essential cellular organelles with complex architectures. Their earliest assembly intermediate--the cartwheel--has a 9-fold symmetry established by Spindle assembly abnormal protein 6 (SAS-6). We used cryo-electron tomography and sub-tomogram averaging to resolve the native structure of the SAS-6 rings within the cartwheel of the exceptionally long Trichonympha proximal centriole. A 16-nm axial periodicity was formed by stacked rings of V-shaped SAS-6 tetramers, which formed the fundamental unit of the cartwheels central hub. SAS-6 head domains adopted a zigzag stacking pattern. Furthermore, the improved resolution provides new insights into the function of the previously observed central inner domain, which forms nine asymmetric densities that bridge adjacent tetramers, thereby imparting polarity and enhancing structural stability. Molecular dynamics simulations indicate increased rigidity in inter-tetramer interactions, supporting efficient ring formation and revealing how cartwheel architecture and polarity are established and stabilized.

cell biology↗

bioRxiv2026

Cryo-EM elucidation of stoichiometric plasticity, asymmetric ligand recognition and allosteric coupling in human P2X2/3 heterotrimeric channels

P2X receptors are trimeric ATP-gated ion channels that assemble as homo- or heterotrimers, with heteromeric forms exhibiting intrinsic asymmetry that influences function. Here, we report four high-resolution cryo-EM structures of human P2X2/3 heterotrimers representing distinct functional states, including ATP-bound assemblies (P2X332 and P2X223), the apo form, and a ligand/ATP-bound closed conformation. The three ATP-binding sites show asymmetric recognition of MgATP{superscript 2}- and ATP-, and channel activation requires occupancy of only two MgATP{superscript 2}- molecules. Gefapixant binds a single allosteric site and selectively inhibits MgATP{superscript 2}-, but not ATP-, binding, indicating orthosteric-allosteric coupling within the heterotrimer. Structural features of the transmembrane domain define ion permeation, particularly for Ca{superscript 2}. Despite asymmetric ligand interactions, gating remains largely symmetric, with minor differences in desensitization. These findings provide a structural framework linking asymmetry to coordinated channel function and open avenues for subtype-selective therapeutic intervention.

biophysics↗

bioRxiv2026

Midazolam suppresses glioma progression by attenuating neuronal activity and downregulating IGF1 signaling

Glioma is the most common primary malignant tumor of the brain, and accumulating evidence indicates that neuronal activity plays a pivotal role in tumor progression. In this study, neuronal activity is modulated in vitro using potassium chloride (KCl)-induced depolarization and midazolam (MDZ)-mediated suppression. MDZ is a neuronal activity modulation medication, commonly used for sedation, anxiolysis, and amnesia in clinics. After treatment, conditioned media derived from these neuronal cultures are subsequently co-cultured with glioma cells. EdU incorporation assays demonstrate that MDZ significantly inhibits glioma cell proliferation in vitro. Furthermore, an orthotopic xenograft glioma model is established to assess the anti-tumor efficacy of MDZ in vivo, as evaluated by tumor volume and Ki-67 immunostaining. Mechanistically, insulin-like growth factor 1 (IGF1) is identified as the neuronal-activity-regulated factor that promotes glioma growth through activation of the PI3K/AKT signaling pathway. Moreover, transcriptomic profiling of brain tissues reveals that MDZ attenuates neuronal activity and downregulates neuron-derived growth factors in both glioma and non-tumor regions, thereby exerting anti-tumor effects in vivo. Collectively, these findings demonstrate that MDZ suppresses glioma progression by suppressing neuronal activity and inhibiting neuron-derived trophic factors, providing new insights into the development of therapeutic strategies for glioma.

neuroscience↗