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Ye, L.

Publications and source records attributed to Ye, L..

At least 19 recordsLinked to original sources

Multi-resolution humanness scoring of antibodies via a region-isolated language model

Antibodies recognized as foreign can elicit anti-drug antibodies that compromise efficacy and safety, making humanness scoring, estimating how human-like a sequence appears, an early, repeated step in antibody development. Widely used scores reduce a variable domain to a single framework-dominated number, leaving the complementarity-determining regions (CDRs) grafted during humanization, diversified by generative models weakly supervised and rarely audited. Here we introduce IgScope, a 23-million-parameter antibody language model trained from scratch that scores humanness at chain, IMGT-region, and residue resolution; a region-isolated attention module confines attention to within-region pairs, and chimeric-sequence training supplies region-level supervision. On 2.38 million held-out chains, masking all framework tokens leaves CDR accuracy unchanged, and back-mutated murine residues in human frameworks are detected at 93.4% accuracy. At chain level, IgScope matches the strongest published correlation with clinical anti-drug-antibody incidence (r = 0.567, n = 217) and outperforms a same-protocol recomputation. Region-level scoring exposes what chain-level scoring conceals: antibodies designed de novo by four generative models pass whole-chain humanness (0.966-0.988), while their CDRs score far below natural (P < 1e-30) in every chain class. Quality control turns the same resolution to the mirror-image question: in humanized-mouse platforms, whose domains are human by design, IgScope scores the domain as human and, in HUGO-Nano chimeric VHHs, isolates only the FR2 signal of four camelid hallmark residues deliberately retained to stabilize the VHH. IgScope gives antibody humanization a verified foundation and generative design an audit.

bioinformatics↗

A gut-brain microbial sensing pathway mediates host defense and bacterial clearance

The digestive tract is a major site of nutrient absorption. It also harbors the densest microbial communities in our body. It is well known that the brain perceives ingested nutrient information through the intestinal epithelium enteroendocrine cell (EEC)-vagal pathway. Little is known about how the brain senses gut bacteria that reside in the intestinal lumen. In this study, we combined novel in vivo EEC calcium imaging, EEC optochemical stimulation, and vagal sensory neuron calcium imaging in the zebrafish model, and revealed that segregated pathways mediated by different EEC and vagal sensory neuron subtypes differentially perceive beneficial nutrient information and harmful irritant pathogenic bacterial information. Our study revealed that a group of EECs that express the nociceptive receptor Transient receptor potential ankyrin A1 (Trpa1) can be activated by the pathogenic bacterium Edwardsiella tarda (E. tarda) or E. tarda-produced irritant metabolites. These Trpa1+EECs do not sense nutrients. Trpa1+EECs, but not other EECs, uniquely and highly express both Serotonin and the neuronal peptide Pituitary adenylate cyclase-activating polypeptide (Pacap). Using pharmaceutical and genetic approaches, our data showed that Pacap synergizes with Serotonin and is required for Trpa1+EEC-induced vagal activation. Stimulating the Trpa1+EEC-vagal sensory pathway potently inhibits a group of vagal motor neurons that innervate visceral organs in the caudal dorsal motor nucleus of the vagus (cDMV). However, the same group of cDMV neurons is activated by nutrients. Microbially induced cDMV inhibition enhances liver gluconeogenesis and promotes intestinal neutrophil recruitment. Inhibiting glucose metabolism, disrupting Trpa1+EEC-vagal sensory pathway, or optogenetically activating cDMV neurons in E. tarda colonized zebrafish induces intestinal E. tarda to switch from an aggregated phenotype to a diffused phenotype and hinders E. tarda clearance. Furthermore, our data show that disrupting the Trpa1+EEC-vagal sensory pathway impairs intestinal neutrophil recruitment and hinders survival, suggesting a protective role of the Trpa1+EEC-vagal microbial sensing pathway in pathogen defense. Together, our data revealed that a distinct non-nutrient-sensing Trpa1+EEC-vagal circuit senses gut microbial irritants, coordinating neuronal, metabolic, and immune responses to enhance host defense and pathogen clearance.

neuroscience↗

Lactation Remodels the Maternal Lung to Promote Preemptive Innate Defense

Lactation is a hallmark of mammalian evolution, imposing extraordinary physiological demands on mothers to nourish their offspring. Yet how mothers maintain their own health while meeting these demands remains poorly understood. Here, we discover that lactation establishes a preemptive innate defense program in the maternal lung through enhanced epithelial production of surfactant proteins and mucin, vascular remodeling that supports granulocyte recruitment and accumulation of activated intravascular neutrophils. These tissue-wide adaptations safeguard lactating dams against diverse respiratory pathogens. We further identify prolactin and CGRP as neuroendocrine signals contributing to pulmonary remodeling and uncover parallel lactation-associated granulocyte adaptations in marsupial and non-human primate models. Together, our findings expand the framework of reproductive immunology, revealing that reproduction couples systemic fetal tolerance with tissue-specific immune adaptations that safeguard maternal health during lactation.

immunology↗

An Excelled Trifluorinated Probe for GPCR Conformational Quantification

G protein-coupled receptors (GPCRs) represent the largest membrane protein family in the human body and the major targets of FDA-approved medications. Unlike some other physiological proteins, GPCRs are highly plastic and often exist as collections of conformational ensembles in the environment to exert their function. Therefore, understanding how a GPCR adopts different conformational ensembles in response to ligands and signaling partners is essential for drug development. 19F-NMR has emerged as one of the most promising tools in this regard; however, a well-established 19F-labeling system is still lacking, including an effective 19F probe that meets both environmental susceptibility and NMR sensitivity requirements, even though progress has been made dramatically in recent years. Thus, this manuscript reports a novel conformational probe (4-(bromomethyl)-ethoxy-2-(trifluoromethyl)benzene, BTMB) that offers paramount benefits for future GPCR conformational dynamics studies. To rationalize the mechanism behind BTMB's superiority for future probe development, we performed MD simulations, referenced to the current state-of-the-art probe, BTFMA. Our study suggests that the spatial proximity of aromatic residues significantly influences the chemical shift dispersion and linewidths of related 19F-probe-profiled conformational states, as well as the rigidity and compactness of -CF3 in the target protein.

biophysics↗

Ligand-Specified Signaling Efficacy Defined by Unique Transitions in G Protein Conformations

Despite decades of research into the signaling efficacy of G protein-coupled receptors (GPCRs), including the resolution of numerous receptor structures in complex with nucleotide-free G proteins1,2, mini-G proteins3,4, and G protein carboxyl-terminal peptides5-7, our understanding of the underlying mechanisms remains elusive, because a fluidic, dynamic view of the conformational transitions during GPCR activation is still missing. Benefiting from its supersensitization to microenvironmental changes, recent advances in 19F-quantitative NMR (19F-qNMR)8 enable the dissection and quantification of the conformational energy landscape and dynamics of receptors and their signaling partners, offering new perspectives for deciphering the signaling machinery through a novel lens. Herein, we first established a 3-state model of Gs conformational landscape and then quantitatively investigated the conformational transitions and dynamics of Gs proteins in response to different ligand-bound receptors. Our research demonstrated that Gs substates are not only differentially populated in a ligand-dependent manner but also undergo distinct conformational-cycling kinetics across sub-states in response to different ligand bindings. These discoveries enable us to propose a novel GPCR model that integrates quantitative G protein conformational dynamics at the atomic level to explain GPCR pharmacological efficacy, emphasizing that unique equilibrium and transitions of G protein conformational states in response to ligands are critical determinants of signaling specificity.

biophysics↗

Ventral tegmental area acetylcholine generates appetitive and aversive incentive motivation

Ventral tegmental area neurons participate in reward learning, motivation, and movement but also have an emerging role in the regulation of aversive behaviors. While these diverse contributions have been attributed to distinct projections of ventral tegmental area neurons, it remains unresolved how these neurons inherit their array of behavioral functions. The ventral tegmental area is rich with acetylcholine receptors and receives dense cholinergic input from the mesopontine tegmentum. While it is known that acetylcholine release in the ventral tegmental area can increase dopamine output we lack an understanding of the scenarios which necessitate ventral tegmental area acetylcholine release. We sought to provide a comprehensive overview of the participation of ventral tegmental area acetylcholine signaling across valence to motivated behavior. Rats were trained on a diverse array of tasks that allowed for the isolation of the contribution of acetylcholine release in the ventral tegmental area to cue- and context-driven behavior. We used intracranial pharmacology to determine the receptor mechanisms that contribute to acetylcholines effects. Ultimately, we found that acetylcholine release in the ventral tegmental area is necessary for appetitive and aversive states to become motivationally relevant and spur reward-seeking and threat-avoidance. We propose that this state-dependent contribution allows ventral tegmental area acetylcholine to act as a motivational gate for behavior across valence. This work expands our view of the interaction between neuromodulatory systems in the brain and opens new directions to the understanding of ventral tegmental area neurons in health and disease.

neuroscience↗

Learning Shapes the Energy Cost of Neural Tasks

The stark difference in energy use between AI systems and biological brains highlights both the remarkable efficiency of the brain and our limited understanding of the energetics underlying neural computation. Although efficiency is widely cited as a principle of neural design, direct measurement of the energy cost of specific neural tasks within their corresponding circuits has remained limited. Here, by simultaneously measuring intracellular glucose and calcium dynamics in the same behaving mice in vivo, we use neuronal glucose consumption to define circuit-level energy costs associated with learning-based behavioral tasks. We found that the post-learning fuel cost per task was significantly lower than pre-learning levels across multiple hippocampus- and cortex-dependent learning models, with or without changes in bulk calcium dynamics. This change in fuel cost was not mediated by extracellular glucose transport but instead reflected a reduction in intracellular glucose consumption and depended on canonical plasticity mechanisms, including NMDAR signaling and protein synthesis. Together, these findings suggest that attenuation of task-specific energy cost may represent a general bioenergetic trajectory of learning and plasticity. This "energy minimization" hypothesis provides insight into how the biological brain achieves efficiency and offers an orthogonal, complementary perspective to neural activity-centered frameworks.

neuroscience↗

ARID4 Modulates Stomatal ABA Signaling and Stress-Responsive Gene Expression to Confer Drought Tolerance in Arabidopsis

To identify novel regulators of plant drought tolerance, we performed a forward genetic screen using thermal infrared imaging to detect alterations in leaf temperature, a proxy for transpiration. This screen identified AT-rich Interacting Domain Protein 4 (ARID4), a protein involved in chromatin remodeling, as a modulator of transpiration. arid4 loss-of-function mutants exhibited cooler leaves, increased water loss from detached leaves, and heightened susceptibility to drought relative to wild-type plants. Stomata of arid4 mutants were hyposensitive to abscisic acid (ABA), displaying reduced ABA-induced reactive oxygen species (ROS) production and impaired stomatal closure. Transcriptome profiling under drought revealed extensive misregulation of genes involved in stress-responses, redox homeostasis, iron acquisition, and photosynthesis. These findings indicate that ARID4 modulates the expression of key regulatory genes to maintain redox homeostasis and photosynthetic efficiency, thereby conferring drought stress tolerance.

Plant Biology↗

Targeting cancer-associated cell surface RNAs with oligonucleotide-drug conjugates enables broad antitumor activity

Recent studies have revealed the presence of RNAs on mammalian cell surfaces, yet the linkage of cell surface RNAs (csRNAs) to cellular states and their potential as extracellular accessible drug targets remains unexplored. Here we develop Cell-surface and Intracellular RNAs Co-mapping (CIRCmap), a highly multiplexed in situ profiling approach that simultaneously detects thousands of cell-surface and intracellular RNAs at single-cell resolution. Using CIRCmap, we uncover that csRNA distributions are correlated with cellular states and identified cancer-associated csRNAs. Integrative analysis of cell-surface and intracellular RNAs within the same cells implies that the csRNAs undergo endocytosis and endolysosomal trafficking, which is further supported by perturbation experiments and co-localization visualization. We design oligonucleotide-drug conjugates (ODCs) that target cancer-associated csRNAs for endocytic delivery of cytotoxic payloads selectively to cancer cells. ODCs exhibit broad antitumor activity in cell lines and an in vivo mouse tumor model, opening a promising new avenue for targeted cancer therapy.

cell biology↗

Top-down regulation of ingestive behavior fragmentation

AbstractIn natural environments, animals rarely feed continuously to satiation; instead, feeding occurs in brief bouts separated by pauses. This fragmentation is thought to balance internal drives with external demands, yet its underlying neural mechanisms remain unclear. By combining bidirectional neural activity mapping and behavioral phenotyping, we identify a projection from the dorsal subiculum (dSub) of the hippocampus to the mammillary body (MB) as a key regulator of this fragmentation. Activity along the dSub-MB pathway tracks and gates the duration of individual feeding bouts, independent of homeostatic state. A simple bistable attractor model captures both dSub-MB neural dynamics and associated behaviors across optogenetic and behavioral perturbations. Together, these findings identify a top-down circuit mechanism that implements action selection in a naturalistic setting.

neuroscience↗

Digital Twin Brain simulation and manipulation of a functional brain network underlying mental illness

Linking synaptic-level perturbations to distributed brain-network dynamics remains a central challenge for understanding and treating mental illness. Although recent whole-brain models can reproduce individual brain activity patterns, they largely function as descriptive simulators rather than mechanistic, intervention-capable systems. Here we present an intervention-capable digital twin of the human brain, integrating individual neuroanatomy and task-evoked dynamics within a neuronal-scale framework. Individualised digital twin brains recapitulate a participant-specific compact cortico-subcortical network phenotype that captures transdiagnostic psychopathology across population and clinical cohorts. In silico modulation of excitatory and inhibitory synaptic conductance produces bidirectional, heterogeneous network responses across individuals. Population-scale simulations stratify individuals and predict longitudinal symptom trajectories from DTB-derived response profiles. Independent pharmacological functional MRI data further validate the predicted baseline-dependent network responses in vivo. Together, these findings establish digital brain models as experimental platforms for mechanistic perturbation, behavioural prediction and stratification, providing a foundation for precision neuroscience and psychiatry.

neuroscience↗

Metformin Stabilizes the Abdominal Aorta in Aneurysm by Restoring VSMC Mitochondrial Homeostasis via the AMPK-SIRT1-PGC-1α Axis

BACKGROUNDAbdominal aortic aneurysm (AAA) is a life-threatening condition with >80% mortality upon rupture and no effective pharmacotherapy available. Despite epidemiological evidence linking metformin use to reduced AAA progression, its mechanism remains elusive. Notably, peroxisome proliferator-activated receptor {gamma} coactivator 1 (PGC-1, encoded by Ppargc1a) is downregulated in human AAA, yet its functional role in metformins protection is unknown. METHODSWe employed porcine pancreatic elastase (PPE)-induced murine AAA, VSMC-specific Ppargc1a knockout (Ppargc1aVSMC-KO), primary VSMC senescence models, and pharmacological inhibition (Compound C for AMPK; Ex-527 for SIRT1) to define the AMPK-SIRT1-PGC-1 axis. RESULTSMetformin significantly inhibited AAA expansion, suppressed VSMC senescence (p53/p21{downarrow}, SA-{beta}-gal{downarrow}), and preserved contractile phenotype (SMTN{uparrow}, IL-6/TNF-{downarrow}). Crucially, all benefits were abrogated in Ppargc1aVSMC-KO mice, which exhibited accelerated aneurysm growth, mitochondrial fragmentation, ATP depletion, and ROS accumulation. Mechanistically, metformin activated AMPK/SIRT1 to upregulate PGC-1; AMPK or SIRT1 inhibition blocked this cascade and reversed protection. CONCLUSIONMetformin restrains AAA by restoring VSMC mitochondrial homeostasis via the AMPK/SIRT1[->]PGC-1 axis, positioning PGC-1 as a non-redundant, cell-autonomous guardian against vascular degeneration. These findings provide a mechanistic foundation for repurposing metformin and developing PGC-1-targeted therapies in AAA.

cell biology↗

Endothelial PTBP1 Deletion in Transplanted Cardiac Tissue Limits Cardiac Allograft Vasculopathy

BackgroundCardiac allograft vasculopathy (CAV) is a leading cause of late graft failure and mortality following heart transplantation, with limited therapeutic options. Endothelial cells (ECs), at the interface between the donor graft and host immune system, play a central role in CAV development. However, the molecular mechanisms driving endothelial dysfunction and vascular remodeling in chronic heart transplant rejection remain poorly understood. MethodsTo characterize endothelial alterations associated with CAV, we isolated nuclei from cardiac tissues of four human donor groups: (1) early post-transplant CAV-negative surveillance biopsies, (2) CAV-negative explanted grafts with acute cellular rejection (ACR), (3) late-stage CAV-positive explanted grafts, and (4) naive non-transplanted control hearts. We applied intranuclear cellular indexing of transcriptomes and epitopes (inCITE-seq) to profile endothelial gene expression together with nuclear protein levels of splice factor polypyrimidine tract-binding protein 1 (PTBP1), a key post-transcriptional regulator of endothelial inflammatory responses. Functional relevance of PTBP1 was assessed using endothelial-specific deletion of Ptbp1 in an F1 hybrid murine model of CAV. ResultsIn human CAV, endothelial cells exhibited increased transforming growth factor-{beta} (TGF-{beta}) signaling and reduced oxidative phosphorylation (OxPhos) transcripts. Nuclear PTBP1 protein levels were markedly elevated in CAV endothelium and were associated with TGF-{beta}-responsive transcriptional programs and correlated with clinical indices of cardiac dysfunction. In murine heart transplants, endothelial-specific deletion of Ptbp1 markedly reduced hallmarks of CAV, including neointimal hyperplasia, fibrosis, and lymphocyte activation. At the molecular level, endothelial Ptbp1 deletion prevented suppression of mitochondrial transcripts and preserved mitochondrial content and integrity under hypoxic stress, attenuating interferon signaling in endothelial cells. ConclusionThese findings identify PTBP1 as a central endothelial regulator linking pro-fibrotic stress to mitochondrial dysfunction and immune activation in chronic cardiac allograft rejection. Targeting endothelial PTBP1 may represent a strategy to limit chronic graft injury while minimizing systemic immunosuppression.

immunology↗

SMECT: a framework for benchmarking post-GWAS methods for spatial mapping of cells associated with human complex traits

Spatially resolving the cellular basis of complex human traits is essential for elucidating disease mechanisms, yet the comparative performance of computational methods for this task has not been systematically evaluated. Here, we present SMECT (Spatial Mapping Evaluation of Complex Traits), the first comprehensive framework for systematically evaluating methods that integrate genetic data with spatial transcriptomics. SMECT combines a biologically realistic simulation engine, a curated resource of 21 diverse real-world datasets, and a multi-faceted assessment toolkit. Using this framework, we benchmarked three state-of-the-art methods--DESE, S-LDSC, and scDRS--across 19 complex traits. Our analysis reveals a fundamental trade-off between detection sensitivity and biological specificity. We demonstrate that while S-LDSC identifies extensive spatial signals, it suffers from inflated non-specific significant associations. Conversely, scDRS is highly specific but conservative, performing well only in tissues with strong biological signals while missing subtle associations in sparser datasets. DESE overcomes these limitations, consistently achieving high power and robust specificity across both simulated and real-world scenarios. SMECT provides critical guidelines for method selection and serves as a foundational resource for developing robust spatial analyses of human complex traits. The framework is publicly available at https://github.com/pmglab/smect.

bioinformatics↗

3D Visualization and Proteomic Analysis of Human Cardiac Transthyretin Amyloidosis Tissue Reveals Microangiopathy and Capillary Occlusion

AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSBackgroundC_ST_ABSTransthyretin amyloidosis (ATTR) is a progressive, degenerative disease affecting the heart and other organ systems, as well as the peripheral, autonomic, and central nervous systems. Although pharmacological and genetic evidence establishes aggregation as a driver of ATTR pathology, the mechanism by which aggregation compromises post-mitotic tissue function is poorly understood. We utilized bottom-up proteomics on wild-type (WT) human cardiac (WT/WT genotype) and V122I human cardiac (V122I/WT genotype) tissue, combined with tissue clearing technology to create an optically transparent tissue architecture to visualize three-dimensional relationships, to better understand TTR cardiomyopathy (CM). MethodsFlash-frozen 0.5 mm cardiac tissue slices from human subjects with end-stage WT-TTR CM, end-stage V122I CM, and slices from an age-matched human control were used for these experiments. Fibril extraction from diseased tissue followed published protocols. Strong denaturant-mediated proteome tissue extraction on samples from each subject facilitated bottom-up proteomics by using liquid chromatography (LC)-mass spectrometry (MS)/MS. Tissue clearing was performed on 0.5 mm cardiac slices utilizing a lauryl sulfate-based lipid removal strategy. Slices were stained using indirect immunofluorescence with antibodies to protein targets identified by proteomics. We used an antibody to non-native TTR and AmyTracker 480 (an oligothiophene dye that binds to amyloid fibrils) to image TTR deposits. ATTR fibrils were characterized structurally using cryogenic electron microscopy (cryo-EM) followed by helical reconstruction. ResultsProteomic cardiac analysis afforded high spectral counts for transthyretin (TTR) and proteins typically associated with amyloid fibrils, e.g. serum amyloid P (APCS). Fibril and cardiac homogenate proteomics revealed high levels of angiogenic and hemostatic proteins, including those composing the complement and coagulation cascades. 3D imaging revealed loss of normal microvascular architecture in CM samples with regions of hyper- and hypovascularization. Microvascular obstruction by capillary thrombosis was also observed in CM. ATTR fibrils adopted the common spearhead fold and were decorated with collagen VI (COLVI), an extracellular matrix component. ConclusionsWe hypothesize that ATTR CM is a microangiopathy driven by capillary bed thrombo-inflammation and dysregulated angiogenic revascularization. Phenotypic convergence of WT ATTR CM and V122I ATTR CM was observed via proteomics, 3D imaging, and ex vivo fibril characterization by cryo-EM. We provide evidence of capillary thrombosis in ex vivo ATTR CM tissue. Vasodilation and increased capillary permeability expose components of the vascular basement membrane (VBM) to misfolded TTR. These components are known to promote TTR aggregation and stabilize amyloid fibrils in the extracellular space. Congestion of the VBM prevents appropriate revascularization, reducing cardiac exertional capacity over time, leading to heart failure. Our ATTR CM heart tissue proteomics data shows significant overlap with the proteomic profiles of human AD brain tissues, revealing key amyloid, coagulation, complement, and angiogenesis proteins being changed in amyloidoses.

pathology↗

Intermittent AP-1 activation in muscles contributes to exercise-induced health benefits

Regular physical exercise extends healthspan, yet the molecular mechanisms that translate intermittent contractile stress into lasting benefit remain incompletely understood. Using global nuclear run-on (GRO-seq) in mouse skeletal muscle after treadmill running, we profiled enhancer RNA (eRNA), a sensitive marker of enhancer activity. Activation protein-1 (AP-1), a family of pioneering factors for senescence, emerged as the top transcription factor with motif enrichment in exercise-activated enhancers. Our screen in the contracting C2C12 myotubes pinpointed cFos/JunD as the primary AP-1 factor responsible for contraction-induced transcriptional changes. Muscle-specific overexpression of A-Fos, a dominant-negative mutant of cFos, disrupted transcriptomic responses to exercise and attenuated exercise-mediated improvement in muscle functions. Interestingly, intermittent but not continuous overexpression of cFos/JunD in mouse muscles mimicked exercise-induced transcriptomic changes, increased mitochondrial volume density, enhanced muscle strength and fatigue resistance, and improved glucose tolerance. These results define a transcriptional regulatory signaling pathway linking exercise intermittency to beneficial adaptations and highlight the necessary recovery cycles in training. The paradoxical anti- and pro-aging roles of AP-1 offer insights into the timing and dynamics of stressors and stress responses in shaping senescence and healthspan.

molecular biology↗

Thalamic Interictal Epileptic and Non-Epileptic Events during NREM Sleep in Patients with Focal Epilepsy: a Stereo-EEG Study

BackgroundThalamic recordings are increasingly incorporated into stereo-electroencephalography (SEEG) evaluations of drug-resistant focal epilepsy to guide neuromodulation targeting. Human thalamic electrophysiology, however, is poorly defined, limiting the distinction between pathological and physiological activity. Here, we characterized interictal epileptic and non-epileptic events during non-rapid eye movement (NREM) sleep across multiple thalamic nuclei and examined their relationship to seizure outcomes. MethodsWe analyzed NREM sleep SEEG recordings from 64 patients with drug-resistant focal epilepsy. Electrodes sampled four thalamic nuclei: centromedian (CM), pulvinar (Pu), ventral lateral (VL), and ventral posterolateral (VPL). Patients were classified into three outcome groups: favorable, unfavorable, and surgically non-remediable. Rates of thalamic spikes, high-frequency oscillations (HFOs), spike-fast activity, and sleep spindles were analyzed and compared across nuclei and outcomes. FindingsRecordings of the thalamus revealed both pathological and physiological interictal events. Interictal epileptic events were infrequent. Only [~]0.2% of seizure-onset zone spikes propagated to the thalamus. Thalamic spike-fast activity was indicative of unfavorable surgical outcomes (CM: p = 0.047, d = 0.46) or surgically non-remediable epilepsy (VL: p = 0.002, d = 0.84). In contrast, thalamic sleep spindles were ubiquitous but reduced in surgically non-remediable patients (CM: p = 0.031, d = -0.58; VL: p = 0.005, d = -0.79). Finally, unique thalamic SEEG patterns were identified, including spikes concomitant with spindles, isolated spikes, and physiological fast ripples. InterpretationThis study provides a comprehensive characterization of thalamic interictal events during NREM sleep, enriching our understanding of thalamic pathophysiology and highlighting the value of thalamic recordings in presurgical evaluation.

neuroscience↗

Functional Characterization of Hsp110 in Drosophila Reveals its Essential and Dosage-Sensitive Role in Nervous System Integrity

The Hsp70 molecular chaperone system is the front line of defense in maintaining cellular proteostasis. In eukaryotes, ATP/ADP nucleotide exchange in the Hsp70 chaperone cycle is stimulated by Hsp110, a divergent member of the Hsp70 chaperone superfamily and co-chaperone of Hsp70. Hsp110 is also a known modifier of neurodegenerative and other protein misfolding-related disorders. Biochemical aspects of Hsp110 chaperone functions have been characterized in vitro, and pathway interactions have been extensively characterized genetically in yeast model systems; however, a detailed understanding of its physiological roles in metazoans, particularly in the nervous system has not been carried out. Taking advantage of the single Hsp110-encoding gene in the Drosophila genome, we conducted a comprehensive investigation of its expression and function in this animal model. Notably, Drosophila and human Hsp110 share significant similarity in their sequence, structure, and splicing variants. At the protein level, Hsp110 is ubiquitously expressed, with both cytosolic and nuclear distribution in a tissue-dependent manner. Functionally, while Hsp110 is dispensable for cell proliferation in developing larvae, it is essential for long-term cell survival and normal development of the nervous system, including non-autonomous effects on neuronal differentiation and glial cell migration. Furthermore, despite being identified as a potent suppressor of protein aggregation and neurotoxicity in multiple neurodegenerative diseases, higher levels of Hsp110 are detrimental in flies. Overexpression of Hsp40, another key co-chaperone of Hsp70, can mimic this effect. However, simultaneous overexpression of both Hsp40 and Hsp110 does not further exacerbate their detrimental effect. Together, these results demonstrate a critical role of Hsp110 in neuronal development and cell survival, and further suggest that in vivo, the levels and activities of Hsp110 and Hsp40 co-chaperones need to be properly balanced. Furthermore, this work supports the contention that the Hsp70 chaperone network must be considered as a whole when targeted for potential therapeutic purposes to meet the complex pathophysiological demands in multicellular organisms.

developmental biology↗