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Biology subjects

Zhao, S.

Publications and source records attributed to Zhao, S..

At least 55 records · Page 3Linked to original sources

In vivo-compatible spatial multi-omics via hydrogen peroxide-independent APEX2 labeling

Proximity labeling (PL) technologies like APEX2 have transformed spatial multi-omics in live cells, but their long-standing dependence on hydrogen peroxide (H2O2) disrupts redox signaling and prevents use in live animals. Here we introduce H2O2-independent APEX2 (Hi-APEX), which uses a clickable tetrazine-phenol probe, requiring no enzyme engineering. We show that APEX2 directly catalyzes TP radical formation without H2O2 via a mechanism requiring the probes tetrazine group and a key histidine residue. We benchmarked Hi-APEX-based spatial multi-omics by mapping the mitochondrial matrix and dynamic secretomes. Hi-APEX significantly outperforms traditional APEX in capturing redox-sensitive processes such as stress response and ferroptosis, enabling discovering authentic stress granule components and protein interaction networks for mitochondria-localized GPx4. One mGPx4 interactor TRMT61B--known to regulate mitochondrial m{superscript 1}A modifications--promotes ferroptosis. Crucially, Hi-APEX achieves full in vivo compatibility, enabling direct PL in tumor xenografts and hippocampal neurons, thereby expanding PL-based spatial multi-omics from cellular systems to living organisms.

biochemistry↗

Telomere-to-telomere gap-free genome assembly integrated with multi-omics uncovers shading mediated regulation of leaf aroma biosynthesis in aromatic crop Pandanus amaryllifolius

Pandanus amaryllifolius is a valuable aromatic crop widely cultivated in tropical forest understories. Here, A telomere-to-telomere, gap-free genome assembly of the Chinese cultivar Taishan Banlan was generated, and the molecular basis underlying shading-mediated regulation of leaf aroma biosynthesis was elucidated for the first time through integrated genomic, transcriptomic, and metabolomic analyses. Volatile metabolomics identified 1599 volatile organic compounds in leaf tissue, with terpenoids as the primary contributors to leaf aroma. Shading modulated the aroma quality of P. amaryllifolius primarily via terpenoid biosynthesis, yielding aroma profiles dominated by sweet, fruity, green, and woody notes. Integrated transcriptomic profiling revealed that terpenoid biosynthesis is co-regulated by structural genes in the MVA/MEP pathways, TPS family members, and key transcription factors, which collectively modulate the biosynthesis and accumulation of the three core differential terpenoids. Our findings provide valuable resources for the targeted genetic improvement and efficient cultivation optimization of P. amaryllifolius.

genomics↗

Multiscale Symbolic Morpho-Barcoding Reveals Region-Specific and Scale-Dependent Neuronal Organization

Neuronal morphology is a central determinant of circuit organization, yet its multiscale complexity has hindered systematic, brain-wide analysis and integration with anatomical context. Here we introduce Multiscale Morpho-Barcoding (MMB), a framework that encodes whole-brain neuronal morphology into symbolic representations spanning cellular geometry, axonal tract routing, arbor organization, and predicted synaptic distributions. Applying MMB to 1,876 fully reconstructed mouse neurons, comprising 3,776 arbors and 2.63 million predicted presynaptic sites, we identify distinct multiscale morpho-patterns that reveal region-specific and scale-dependent principles of neuronal organization across the brain. MMB robustly discriminates major anatomical divisions and resolves canonical thalamic circuit classes beyond what can be achieved using projection strength alone. By transforming complex neuronal geometry into interpretable multiscale representations, MMB provides a general framework for systematic comparison of neuronal structure and for integrating morphology with connectivity and function at whole-brain scale.

bioinformatics↗

MG53 Protects Against Intestinal Inflammation by Inhibiting NLRP3 Inflammasome Activation

Background and ObjectivesInflammatory bowel disease (IBD) involves dysregulated immune responses and chronic intestinal inflammation. The nod-like receptor pyrin domain-containing 3 (NLRP3) inflammasome plays a critical role in IBD pathogenesis, but regulatory mechanisms remain not fully understood. Mitsugumin 53 (MG53, also known as TRIM72), originally identified as a critical membrane repair protein, has emerged as a novel regulator of inflammatory processes. To investigate the protective role of MG53 in colitis and elucidate its mechanisms in regulating NLRP3 inflammasome activation in IBD. MethodsWe used dextran sodium sulfate (DSS)-induced colitis models comparing MG53 knockout (MG53-/-) and wild-type (WT) mice, assessing disease severity, MG53 tissue uptake, and therapeutic effects of recombinant human MG53 (rhMG53). In vitro studies examined rhMG53s effects on NLRP3 inflammasome activation, caspase-1 cleavage, interleukin-1{beta} (IL-1{beta}) secretion, and MG53-NLRP3 interactions. ResultsMG53-/- mice showed more severe colitis with increased weight loss, higher disease activity scores, shortened colons, and greater inflammation. DSS treatment induced the accumulation of circulating MG53 in inflamed colonic tissue. rhMG53 administration ameliorated colitis severity in MG53-/- mice and dose-dependently suppressed NLRP3 inflammasome activation in vitro. MG53 interacted with NLRP3 and reduced apoptosis-associated speck-like protein containing a CARD (ASC) speck formation and NLRP3 oligomerization without affecting upstream signaling or NLRP3 stability. ConclusionMG53 is a physiological regulator of NLRP3 inflammasome activation that protects against colitis, suggesting therapeutic potential for IBD.

immunology↗

Non-enzymatic ABHD6 interacts with Akt-FoxO1 axis to regulate selective hepatic insulin resistance

The enzymatic function of ABHD6 on insulin secretion and insulin resistance is well documented. However, its non-enzymatic function, especially its effects on selective hepatic insulin resistance and metabolic dysfunction-associated steatotic liver disease (MASLD) is completely unexplored. ABHD6 is elevated under conditions of diet-induced obesity and aging. To define the role of ABHD6 in liver physiology, we generated liver-specific ABHD6 knockout mice, as well as liver specific overexpression of native and enzymatic inactive mutant ABHD6 mouse models. We demonstrated that ABHD6 is an unidentified regulator of selective hepatic insulin resistance and contributes to MASLD and liver fibrosis. Furthermore, we found that non-enzymatic ABHD6, rather than its enzymatic form, contributes to this regulation. Mechanistically, we found that ABHD6 translocated into the nucleus and interacted with Akt/FoxO1 axis to regulate its function. In addition, knockdown of FoxO1 in primary hepatocytes or overexpression of constitutively active mutant FoxO1 by AAV approach could completely abolish the effects of ABHD6 on glucose tolerance and gluconeogenesis. Our study reveals an entirely different mechanism underlying selective hepatic insulin resistance that involves a previously unknown non-enzymatic function of ABHD6. This study opens an avenue for the development of a novel class of ABHD6 inhibitors to treat MASLD and liver fibrosis. HighlightsO_LIABHD6 expression in the liver is increased with obesity and aging. C_LIO_LIABHD6 manipulation affects selective hepatic insulin resistance, MASLD and liver fibrosis. C_LIO_LINon-enzymatic ABHD6 interacts with Akt/FoxO1 axis to regulate FoxO1 transcriptional activity. C_LIO_LIThe effects of ABHD6 on glucose tolerance and hepatic gluconeogenesis are completely dependent on FoxO1 activity. C_LI

physiology↗

Scattering-enabled epi-quantitative phase imaging reveals subcellular detail in organoids and deep mouse brains

Imaging subcellular structures deep within thick, turbid biological tissues remains fundamentally limited by light scattering, which distorts optical wavefronts and degrades contrast, resolution, and sensitivity. These limitations hinder quantitative interrogation of complex biological systems where resolving dynamic microenvironments at subcellular resolution is critical. Here, we introduce scattering-enabled epi-quantitative phase imaging (SEEQPI), a label-free method that leverages tissue scattering and provides subcellular spatial resolution, nanometer-scale spatiotemporal phase sensitivity, and millimeter-scale imaging depth in murine brains. SEEQPI is enabled by common-path phase-shifting confocal epi-interferometry with near-infrared illumination and the scattering-enabled phase reconstruction algorithm. SEEQPI requires low illumination power, minimizing tissue damage while enabling high-speed imaging of biological dynamics. We demonstrate simultaneous, colocalized imaging of subcellular structures with SEEQPI, third-harmonic generation, and three-photon fluorescence microscopy in liver cancer spheroids and in vivo mouse brains. SEEQPI enables quantitative, longitudinal studies of dry mass dynamics in intact, living biological systems.

bioengineering↗

Lysosomal Aspartylglucosaminidase Couples Glycoprotein Catabolism to Cell-Surface GlycoRNA Production

GlycoRNAs, small non-coding RNAs covalently linked to N-glycans, reveal an unexpected intersection between RNA biology and glycosylation, with potential roles in immunity and cell-cell communication. The origins and biogenesis of their glycans remain unclear. Using CRISPR-Cas9 screening, metabolic glycan labeling and lysosome-targeted proteomics, we reconfirm canonical N-glycosylation enzymes (STT3A/B) and identify components of the mannose-6-phosphate (M6P) lysosomal sorting pathway (GNPTAB, M6PR) as essential contributors. Strikingly, lysosomal aspartylglucosaminidase (AGA) acts as a rate-limiting regulator, linking glycoprotein catabolism to glycoRNA formation. Loss of AGA collapses both abundance and diversity of RNA-linked N-glycans, while pulse-chase tracing shows glycoprotein-derived glycans are repurposed for RNA glycosylation. These findings position lysosomes as active participants in RNA modification and redefine glycoRNA biogenesis as a metabolically integrated process.

cell biology↗

Cortical microglia promote noradrenergic signaling to maintain wakefulness

Microglia are essential for maintaining brain homeostasis, including the sleep-wake cycle, but the underlying mechanisms remain unclear. Here, using in vivo two-photon imaging in both head-fixed and freely moving mice with simultaneous electroencephalogram-electromyogram (EEG-EMG) recording, we investigated microglial process dynamics and their interactions with locus coeruleus (LC) noradrenergic (NE) axons in the frontal cortex across sleep-wake states. During sleep or chemogenetic suppression of LC neurons, microglia enhanced their surveillance and increased interactions with NE axons. Correlative electron microscopy at nanometer resolution identified structural contacts between microglial process endings and NE boutons. Mechanistically, microglia-bouton interaction is primed by NE-{beta}2-adrenergic receptor ({beta}2AR) signaling, leading to enhanced Ca{superscript 2} activity in NE axons. These findings suggest that microglial interactions with NE axons promote cortical norepinephrine transmission and maintain stable wakefulness.

neuroscience↗

Satellite microglia gate neuronal excitability by shielding inhibitory synapses in adult brain

Microglia, the primary immune cells of the central nervous system, are known for sculpting excitatory neural circuits via dynamic processes. However, their role in modulating inhibitory synaptic connections in adulthood remains largely unexplored. In this study, we identified an underappreciated microglia subpopulation, satellite microglia with physical soma-soma contact with neurons, that reshape inhibitory circuit connectivity and gate neuronal activity by shielding inhibitory synapses in the adult mouse brain. Using chronic in vivo two-photon imaging in adult mice, we observed in real time that satellite microglia associations displaced perisomatic inhibitory synapses whereas their dissociation permitted inhibitory synaptogenesis. Redistribution of satellite microglia reorganized inhibitory connectivity, altered local neural networks and changed behaviors. These findings establish satellite microglia as key architects of inhibitory circuitry and suggest their broader role in neural plasticity in health and disease.

neuroscience↗

Integrative Analysis of Spatial Transcriptome and Connectome by SpaCon

The brains structure and function arise from its complex molecular composition and neural connectivity, yet the relationship between cell-type-specific gene expression and brain-wide connectivity is not well understood. By integrating single-cell resolution spatial transcriptomics and connectomics, we reveal tight gene-connectivity coupling in the cortico-thalamic circuit. To uncover the latent factors associating connectivity with gene expression, we focused on the often-overlooked extrasomatic mRNAs in spatial transcriptomics and identified specific gene expression in axons of the corpus callosum that reflect their cortical origins. Building on these findings, we developed SpaCon, a deep-learning method that flexibly integrates global connectivity with local gene expression. SpaCon employs efficient neighbor-sampling to enable whole-brain analysis while preserving performance. This architecture allows the model to identify functionally relevant three-dimensional domains defined by transcriptome-connectome patterns, even when spatially distant. Validated across diverse datasets and species, SpaCon significantly enhances the prediction of connectivity from gene expression and improves the spatial classification of neuronal subtypes. SpaCon provides a powerful, scalable, and versatile framework for understanding transcriptome-connectome relationships.

neuroscience↗

Peri-Head Distance Coding in the Mouse Brainstem

Perceiving object distance in peri-personal space is essential for guiding movement and avoiding danger. During active sensation, distance information is often anchored to the body via touch; yet how early somatosensory circuits extract distance information from tactile inputs remains unclear. Here, we investigate how second-order neurons in the mouse whisker brainstem encode peri-head distance. Using in vivo extracellular recordings in awake mice in a naturalistic wall-passing paradigm, we find brainstem neurons employ two distance-coding schemes: a "proximity" code, where firing increases monotonically as objects approach the face; and a "map" code, where neurons exhibit peak tuning at specific distances to collectively tile peri-head space. The map code outperforms proximity code in population decoding of distance. Perturbation experiments reveal multi-whisker integration and internuclear inhibition contribute to the generation of map-like tuning. These findings highlight a previously underappreciated computational role for brainstem circuits, where inhibition acts as a neural comparator to transform proximity-based sensory inputs into a map-like representation of peri-personal space.

neuroscience↗

Multi-stem-loop constrained library enables accelerated SELEX for aptamers with superior kinetics and affinity

AbstractAptamers are single-stranded nucleic acids with ligand-binding capacity as cost-effective alternatives to antibodies. However, their utility is often undermined by the inherent conformational instability of single-stranded nucleic acids, which can compromise binding kinetics and final affinity. To overcome this critical limitation, we synthesized a novel primary library incorporating multiple inlaid stem-loop structures to enhance molecular stability and rigidity. This structural constraint dramatically accelerated the selection process, allowing us to isolate aptamer candidates with superior affinity in just three rounds of SELEX (Systematic Evolution of Ligands by EXponential enrichment), a significant reduction compared to conventional methodologies. Critically, the resulting aptamer demonstrated higher affinity and faster binding kinetics compared to previously reported sequences, which directly validate our hypothesis that structural stabilization leads to high-performance aptamers. This methodology, which integrated rational conformational constraint with a high-throughput selection process, offered a generalizable strategy to efficiently select aptamers with excellent kinetic and thermodynamic performance for demanding applications such as continuous, real-time ligand detection.

biochemistry↗

Motor Cortical Output Integrates Distorted Proprioceptive Feedback

Proprioceptive feedback from muscles is essential for continuous monitoring and precise control of limb movement, yet how such peripheral feedback is integrated into ongoing descending motor cortical dynamics remains largely unclear. Here we used precisely timed optogenetic stimulation of forelimb muscles to manipulate proprioceptive signals during a mouse reach-to-consume task. Mice were able to successfully reach and consume despite muscle stimulation-evoked forelimb deviations. Across the cortex, the caudal forelimb area (CFA) was preferentially activated by muscle-specific proprioceptive inputs and contributed to stabilizing perturbed forelimb movement. CFA extratelencephalic (ET) neurons encoded movement kinematics as well as proprioceptive feedback. At neuron population level, proprioceptive perturbations rapidly deflected CFA ET neural trajectories away from the task-relevant manifold yet exerted only limited effects on evolving task dynamics. These results reveal that descending cortical circuit implements activity subspace separation to encode and integrate distorted proprioceptive feedback while preserving task-relevant output.

neuroscience↗

Elevated Temperatures Representing Heatwave Conditions Shift Active Nitrifying Communities and Their Viruses in Tidal Flats and Agricultural Soils

Global heatwave intensification associated with climate change will impact the nitrogen cycle, yet its effect on specific nitrifier groups or their interactions with viruses remains unclear. Using 13CO2-DNA-based stable isotope probing (SIP) coupled with metagenomics, we show that elevated temperatures associated with heatwave conditions restructure active nitrifying communities and their viruses in Yangtze River estuary tidal flats and adjacent agricultural soils. In tidal flats, high temperatures shifted active ammonia-oxidizing archaea and bacteria (AOA and AOB), and nitrite-oxidizing bacteria (NOB) from marine to terrestrial ecotypes. In contrast, heatwave conditions stimulated terrestrial ecotypes of AOA but suppressed AOB in agricultural soils. 13C-labeled nitrifier-infecting viruses also showed temperature-driven shifts in activity, lifestyle, and auxiliary metabolic genes in concert with hosts. Notably, AOA viruses carried the plastocyanin gene, potentially augmenting host metabolism. These findings demonstrate heatwaves drive complex shifts in nitrifier communities and their interactions with viruses, impacting global nutrient cycling under climate extremes.

microbiology↗

Computer Vision Methods for Spatial Transcriptomics: A Survey

Spatial transcriptomics (ST) enables the simultaneous measurement of gene expression and spatial localization within tissue sections, providing unprecedented opportunities to dissect tissue architecture and functional organization. As a relatively new omics technology, bioinformatics has driven much of the innovation in ST. However, within these frameworks, "spatial" information is often reduced to locations and relationships between molecular profiles, without fully leveraging the wealth of submicron morphological detail and histological knowledge available. Advances in computer vision-based artificial intelligence (AI) are opening exciting new avenues beyond conventional bioinformatics approaches by modeling complex histological patterns and linking morphology to molecular states. More excitingly, they bring fresh perspectives to potentially address key limitations of ST, including its high cost, limited clinical applicability, and reliance on twodimensional (2D) analysis of inherently three-dimensional (3D) tissues. For instance, models that predict ST directly from histology images enable "virtual sequencing," drastically reducing costs while integrating morphological insights from pathology with molecular biomarkers, thus accelerating clinical translation. Moreover, computer vision techniques can reconstruct pixel-aligned 3D tissue models, overcoming the technical barriers of 2D acquisition and advancing 3D spatial omics analytics. In this paper, we present the first systematic survey of computer vision AI models for ST analytics, categorizing approaches across architectures, learning paradigms, tasks, and datasets, and tracing their technological evolution. We highlight key challenges and future directions, offering a panoramic perspective on vision-driven ST and its potential to transform both basic research and clinical practice. The curated collection of vision-driven spatial transcriptomics papers is available at https://github.com/hrlblab/computer_vision_spatial_omics.

bioinformatics↗

hpGRISZ: a high-performance fluorescent biosensor for in vivo imaging of synaptic zinc dynamics

Despite the crucial role of synaptic Zn2+ in neurotransmission and neural processing, direct in vivo measurement of Zn2+ transients has remained challenging due to the limited responsiveness of existing fluorescent indicators. Here we report hpGRISZ (high-performance green indicator for synaptic Zn2+), an ultraresponsive turn-on green fluorescent biosensor engineered through iterative linker optimization, mutagenesis, and directed evolution. hpGRISZ exhibits exceptional brightness, thermostability, and a large fluorescence response (F/F0 {approx} 25) with micromolar affinity suitable for detecting extracellular synaptic Zn2+ release. We comprehensively characterized hpGRISZ in vitro, in mammalian cells, and in vivo. A membrane-anchored version of hpGRISZ traffics robustly to the cell surface under physiological conditions, where it retains strong responsiveness and supports wide-field, two-photon, and fiber photometry recordings in awake mice. These assays revealed synaptic Zn2+ dynamics across distinct brain regions and neuronal circuits. Together, our findings establish hpGRISZ as a powerful tool for dissecting zinc signaling in neural circuits and as a prototype for next-generation genetically encoded biosensors for in vivo imaging.

neuroscience↗

ChromPolymerDB: A High-Resolution Database of Single-Cell 3D Chromatin Structures for Functional Genomics

The three-dimensional (3D) organization of chromatin plays a critical role in regulating gene expression and genomic processes like DNA replication, repair, and genome stability. Although these processes occur at the individual-cell level, most chromatin structure data are derived from population-averaged assays, such as Hi-C, obscuring the heterogeneity of single-cell conformations. To address this limitation, we developed a polymer physics-based modelling framework, the Sequential Bayesian Inference Framework (sBIF), that deconvolutes bulk Hi-C data to reconstruct single-cell 3D chromatin conformations. To support a broader use of sBIF, we created ChromPolymerDB, a publicly accessible, high-resolution database of single-cell chromatin structures inferred by sBIF. The database contains [~]108 reconstructed 5 kb-resolution single cell structures, spanning over 60,000 genomic loci across 50 human cell types and experimental conditions. ChromPolymerDB features an interactive web interface with tools for 3D structural analysis and multi-omics integration. Users can explore associations between chromatin conformation and gene expression, epigenetic modifications, and regulatory elements. The platform also supports comparative analyses to identify structural changes across cell types, developmental stages, or disease contexts. ChromPolymerDB offers a unique resource for researchers studying the relationship between genome architecture and gene regulation, and for advancing comparative 3D genomics. ChromPolymerDB is available online at https://chrompolymerdb.bme.uic.edu/. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/678816v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@110c807org.highwire.dtl.DTLVardef@bc713forg.highwire.dtl.DTLVardef@1af0ea9org.highwire.dtl.DTLVardef@1eba638_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗