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Biology subjects

Wang, Y.-J.

Publications and source records attributed to Wang, Y.-J..

At least 19 recordsLinked to original sources

Mechanical confinement drives monocyte-to-macrophage differentiation

Cells in vivo experience mechanically diverse microenvironments in which physical confinement is a pervasive but poorly understood regulator of their behavior and fate. Whether and how mechanical confinement governs immune cell differentiation remains unknown. Here, we reveal that a mechanical cue -- long-term confinement is sufficient to drive monocyte-to-macrophage differentiation through a mechanoepigenetic pathway. In vivo, differentiating monocytes exhibited flattened nuclei in the liver capsule, indicative of confinement by surrounding stromal and parenchymal structures. Using a custom cell confiner to recapitulate this confined niche, we found that confinement induces macrophage-like protrusive architectures, enhances motility, and upregulates macrophage-associated genes in RAW264.7 and THP-1 monocyte-lineage cells. Notably, extending this paradigm to primary murine bone-marrow, human umbilical-cord, and tissue-derived hepatic-associated monocytes yielded similar outcomes, thus enhancing phagocytic capacity, directly demonstrating that mechanical confinement can program monocytes into macrophages. Mechanistically, we found that confinement activates KDM6B, leading to H3K27me3 demethylation, which derepresses macrophage-specific transcriptional programs. Pharmacological inhibition of KDM6B with GSK-J4 restored H3K27me3 and blocked macrophage differentiation both in vitro and in vivo. These findings define a KDM6B-H3K27me3 axis that links nuclear mechanics to transcriptional reprogramming, positioning mechanical confinement as a "super-enhancer-like" cue for engineer macrophage function in therapeutic and bioengineering contexts.

cell biology↗

Exploring multi-level microbial interactions from individual 3D genomes to community networks

Microbial communities interact with their hosts through complex genomic networks that influence ecosystem stability and disease progression. Here, we present FindMeta3D, a computational framework that simultaneously identifies microbial three-dimensional (3D) genome structures and cross-domain interaction networks. Applying this approach to 528 Hi-C samples, we resolved 3D genome structures of 344 microbial species, revealing five evolutionarily conserved chromatin folding patterns linked to intrinsic sequence features. Further analyses demonstrated distinct microbial-host interaction preferences and identified functional interaction hotspots that are critical for infection. Experimental deletion of such hotspots in the EBV genome resulted in significant infection defects, demonstrating their essential role in viral infectivity. Additionally, we constructed the first Cross-domain Microbial Interaction Network (CMIN), which uncovered pathogen-specific subnetworks and demonstrate dramatic restructuring of gut microbial communities in neutropenic patients, including enhanced Klebsiella-phage interactions. Subnetwork analysis identified potential phage therapy targets, such as Klebsiella phage ST16-OXA48phi5.4. These findings provide fundamental insights into microbial 3D genomics and establish FindMeta3D as a powerful platform for studying microbial genome structure and communities and developing antimicrobial strategies.

microbiology↗

A non-canonical top-down pathway regulating relapse to opioid

The high relapse rates are major challenges in treating opioid addiction. However, it remains poorly understood the mechanisms underlying long-lasting vulnerability to relapse. Here, we identify the cortico-subthalamic projection from the granular retrosplenial cortex (RSG) to the zona incerta (ZI) as a key circuit for controlling relapse to opioid. We uncover that an ensemble of RSG glutamatergic neurons that locate in layer 5 and express B subtype cholecystokinin receptor (RSGGlu-Cckbr ensemble) are critically implicated in the encoding and retrieval of opioid-associated memories, leading to relapse to opioid via innervating ZI GABAergic (ZIGABA) rather than dopaminergic neurons. We further identify that the Cckergic neurons from anterodorsal nucleus of thalamus (AD thalamus) orchestrates RSGGlu-Cckbr-ZIGABA circuit function via release of cholecystokinin (Cck) in RSG. These results elucidate a previously unknown non-canonical top-down pathway regulating relapse to opioid and shed new light on the development of new therapeutic strategies to treat relapse to opioids.

neuroscience↗

The structure of pairwise competition is responsible for sudden regime shifts in a microbe-plasmid model

Plasmids play a crucial role in bacterial communities by facilitating the horizontal transfer of genetic material, particularly genes that confer resistance to different stressor agents. In this work, we introduce a microbe-plasmid model to study the conditions under which a plasmid-carrying bacterial strain can invade its corresponding plasmid-free counterpart, as well as those under which it can be eradicated from the population through potential intervention strategies. We reveal the variety of dynamic regimes of the model depending on the parameter values. In particular, we show that a heterogeneous structure of the competition between the two strains drives the possibility of coexistence of stationary states (i.e. bistability) which creates conditions for sudden regime shifts and hysteresis. We explore the implications of our results for the potential eradication of plasmid-mediated antibiotic resistance.

ecology↗

Composition of Carotid Plaques Differs Between Chinese and United States Patients: A Histology Study

BackgroundThe clinical manifestations of cerebrovascular disease are known to differ between the Chinese and United States (U.S.) populations as do the plaque features on imaging. ObjectivesThe aim of this study was to investigate and compare the histological features of excised carotid plaques from Chinese and U.S. patients. MethodsCarotid endarterectomy specimens collected from two prospective studies were included. The entire plaque was serially sectioned (10 {micro}m thickness) at 0.5-1 mm intervals. Hematoxylin and eosin staining and Mallorys trichrome staining were performed. The morphology and components of the plaques were measured and compared between the two groups. ResultsA total of 1,152 histological sections from 75 Chinese patients and 1,843 sections from 111 U.S. patients were analyzed. The Chinese group had significantly smaller minimum lumen diameters (median: 1.1 vs. 1.3 mm, p=0.046) and a larger percent wall volume (median: 74% vs. 70%, p=0.018) than the U.S. group. After adjusting for confounding factors, carotid plaques in the Chinese population were more likely to have more lipid pools ({beta}=10.0%, 95%CI: 4.9 to 15.9%), more recent intraplaque hemorrhage (IPH; {beta}=8.4%, 95%CI: 4.5 to 12.7%), and less late IPH ({beta}=-8.2%, 95%CI: -11.3 to -5.4), and fewer fibrous cap disruptions (45% vs. 67%, p=0.061). Chinese plaques were more homogeneous and had a higher percentage of plaques with features of xanthomas than did U.S. plaques (20% vs 2.7%, p<0.001). ConclusionsThe histology of Chinese plaques differs significantly from that of U.S. plaques, suggesting substantial differences in the pathophysiology of atherosclerotic cerebrovascular disease between Chinese and North American populations, which could enhance the gap in racial pathology comparison, indicating a need for a different management approach. Central illustration O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/658993v1_ufig1.gif" ALT="Figure 1"> View larger version (83K): org.highwire.dtl.DTLVardef@14f16corg.highwire.dtl.DTLVardef@f60d66org.highwire.dtl.DTLVardef@1e9a822org.highwire.dtl.DTLVardef@11d7a31_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

Species interactions determine plasmid persistence in a 3-member bacterial community

Microbial communities are shaped by multiple forces, including interspecies interactions and the effects of mobile genetic elements such as plasmids. How these forces interact to affect community responses to environmental perturbations remains unclear, particularly considering the qualitatively different natures and the complexity of competitive and plasmid transfer interactions. We investigated the role of bacterial and plasmid interaction networks in community responses to single and multiple environmental perturbations, using a model community of three bacteria and two plasmids grown in rich media over five 2-day transfers. Bacterial interactions were the primary driver of community response, to the extent that plasmids were not always retained in the community even when they carried relevant resistance genes. Overall, our results indicate that while bacterial and plasmid interactions both shape community responses to environmental perturbations, bacteria-bacteria interactions may be the primary driver of community dynamics and their response to perturbations.

ecology↗

Missense variants in GABAA receptor beta2 subunit disrupt receptor biogenesis and cause loss of function

Gamma-aminobutyric acid type A receptors (GABAARs) are the major inhibitory neurotransmitter-gated channel in the mammalian central nervous system. GABAARs function as heteropentamers, typically composed of two 1, two {beta}2, and one {gamma}2 subunits. Protein homeostasis between GABAAR folding, trafficking, assembly, and degradation is critical to ensure normal physiological functions. Variants in genes encoded for GABAARs lead to numerous neurological disorders, such as genetic epilepsy with or without neurodevelopmental delay. While these variants are associated with severe clinical presentations of epilepsy, the molecular mechanisms driving the disease remain to be elucidated. In this study, we focused on four missense epilepsy-associated variants (EAVs) in the GABRB2 gene: Q209F210delinsH (c. 627_629del), R240T (c. 719G>C), I246T (c. 737T>C), and I299S (c. 896T>G). HEK293T cells exogenously expressing these {beta}2 variants exhibited significantly reduced GABA-induced peak chloride current, indicating their loss of function. However, the four {beta}2 EAVs differed in the degree of proteostasis deficiencies, including increased ER retention, compromised assembly, decreased protein stability, and reduced trafficking and surface expression, with Q209F210delinsH and R240T variants leading to the most severe degradation. Collectively, these results indicate that these epilepsy-linked variants have debilitating effects on the early biogenesis of the {beta}2 subunit, causing misfolding, aggregation, and rapid degradation before it can be assembled with other subunits and transported to the plasma membrane. Overall, our work offers crucial mechanistic insight into how specific {beta}2 missense variants impact the proteostasis maintenance of GABAARs, which could facilitate the development of effective therapeutics for genetic epilepsy by targeting trafficking-deficient GABAAR variants.

cell biology↗

GABRA1 frameshift variants impair GABAA receptor proteostasis

The gamma-aminobutyric acid type A receptor (GABAAR) is the most common inhibitory neurotransmitter-gated ion channel in the central nervous system. Pathogenic variants in genes encoding GABAAR subunits can cause receptor dysfunction and lead to genetic epilepsy. Frameshift variants in these genes can result in a premature termination codon, producing truncated receptor subunit variants. However, the pathogenic molecular mechanism as well as functional implications of these frameshift variants remains inadequately characterized. This study focused on four clinical frameshift variants of the 1 subunit of GABAAR (encoded by the GABRA1 gene): K401fs (c.1200del), S326fs (c.975del), V290fs (c.869_888del), and F272fs (c.813del). These variants result in the loss of one to three transmembrane helices, whereas wild type 1 has four transmembrane helices. Therefore, these variants serve as valuable models to evaluate membrane protein biogenesis and proteostasis deficiencies of GABAARs. In HEK293T cells, all four frameshift variants exhibit significantly reduced trafficking to the cell surface, resulting in essentially non-functional ion channels. However, the severity of proteostasis deficiency varied among these four frameshift variants, presumably due to their specific transmembrane domain deletions. The variant 1subunits exhibited endoplasmic reticulum (ER) retention and activated the unfolded protein response (UPR) to varying extents. Our findings revealed that these frameshift variants of GABRA1 utilize overlapping yet distinct molecular mechanisms to impair proteostasis, providing insights into the pathogenesis of GABAAR-associated epilepsy.

cell biology↗

CellPatch: a Highly Efficient Foundation Model for Single-Cell Transcriptomics with Heuristic Patching

The rapid advancement of foundation models has significantly enhanced the analysis of single-cell omics data, enabling researchers to gain deeper insights into the complex interactions between cells and genes across diverse tissues. However, existing foundation models often exhibit excessive complexity, hindering their practical utility for downstream tasks. Here, we present CellPatch, a lightweight foundation model that leverages the strengths of the cross-attention mechanism and patch tokenization to reduce model complexity while extracting efficient biological representations. Comprehensive evaluations conducted on single-cell RNA-sequencing datasets across multiple organs and tissue states demonstrate that CellPatch achieves state-of-the-art performance in downstream analytical tasks while maintaining ultra-low computational costs during both pretraining and finetuning phases. Moreover, the flexibility and scalability of CellPatch allow it to serve as a general framework that can be incorporated with other well established single-cell analysis software, thereby enhancing their performance through transfer learning on diverse downstream tasks.

bioinformatics↗

Structural insights into terminal arabinosylation biosynthesis of the mycobacterial cell wall arabinan

The emergence of drug-resistant strains exacerbates the global challenge of tuberculosis caused by Mycobacterium tuberculosis (Mtb). Central to the pathogenicity of Mtb is its complex cell envelope, which serves as a barrier against both immune system and pharmacological attacks. Two key components of this envelope, arabinogalactan (AG) and lipoarabinomannan (LAM) are complex polysaccharides that contain integral arabinan domains important for cell wall structural and functional integrity. The arabinofuranosyltransferase AftB terminates the synthesis of these arabinan domains by catalyzing the addition of {beta}-(1[->]2)-linked terminal arabinofuranose residues. Here, we present the cryo-EM structures of Mycobacterium chubuense AftB in its apo and donor substrate analog-bound form, determined to 2.9 [A] and 3.4 [A] resolution, respectively. Our structures reveal that AftB has a GT-C fold transmembrane (TM) domain comprised of eleven TM helices and a periplasmic cap domain. AftB has an irregular tube-shaped cavity that bridges the two proposed substrate binding sites. By integrating structural analysis, biochemical assays, and molecular dynamics simulations, we elucidate the molecular basis of the reaction mechanism of AftB and propose a model for catalysis.

biochemistry↗

A computational and multi-brain signature for aberrant social coordination in schizophrenia

Social functioning impairment is a core symptom of schizophrenia (SCZ). Yet, the computational and neural mechanisms of social coordination in SCZ under real-time and naturalistic settings are poorly understood. Here, we instructed patients with SCZ to coordinate with a healthy control (HC) in a joint finger-tapping task, during which their brain activity was measured by functional near-infrared spectroscopy simultaneously. The results showed that patients with SCZ exhibited poor rhythm control ability and unstable tapping behaviour, which weakened their interpersonal synchronization when coordinating with HCs. Moreover, the dynamical systems modelling revealed disrupted between-participant coupling when SCZ patients coordinated with HCs. Importantly, increased inter-brain synchronization was identified within SCZ-HC dyads, which positively correlated with behavioural synchronization and successfully predicted dimensions of psychopathology. Our study suggests that SCZ individuals may require stronger neural alignment to compensate for deficiency in their coordination ability. This hyperalignment may be relevant for developing inter-personalized treatment strategies.

neuroscience↗

Single-cell RNA sequencing of iPSC-derived brain organoids reveals Treponema pallidum infection inhibiting neurodevelopment

Congenital syphilis is a vertically transmitted bacterial infection caused by Treponema pallidum, often causing multidomain neurodevelopmental disabilities. However, little is known about the pathogenesis of this disease. Brain organoids platform derived from the induced pluripotent stem cell (iPSC) is exposed to T. pallidum infection for modelling congenital neurodevelopmental impairment. Single-cell RNA sequencing is used for identifying the subpopulations of differentially expressed genes and cellular heterogeneity and reconstructing differentiation trajectories following T. pallidum infection. The results reveal that T. pallidum infection influences the formation of neural rosette structures, reduces the cell number of the neural progenitor cell subcluster 1B (subNPC1B) and hindbrain neurons, and affects the neurodevelopment of the brain organoid. Moreover, it is speculated that T. pallidum inhibits the hindbrain neuron cell number through the suppression of subNPC1B subgroup in the organoids and inhibits transcription factor 3 activity in the subNPC1B-hindbrain neuronal axis. This is the first report on the inhibited effects of T. pallidum on the neurodevelopment of the iPSC-derived brain organoid model. T. pallidum could inhibit the differentiation of subNPC1B in brain organoids, thereby reducing the differentiation from subNPC1B to hindbrain neurons, and ultimately affecting the development and maturation of hindbrain neurons.

neuroscience↗

Pathogenicity Prediction of GABAA Receptor Missense Variants

Variants in the genes encoding the subunits of gamma-aminobutyric acid type A (GABAA) receptors are associated with epilepsy. To date, over 1000 clinical variants have been identified in these genes. However, the majority of these variants lack functional studies and their clinical significance is uncertain although accumulating evidence indicates that proteostasis deficiency is the major disease-causing mechanism for GABAA receptor variants. Here, we apply two state-of-the-art modeling tools, namely AlphaMissense, which uses an artificial intelligence-based approach based on AlphaFold structures, and Rhapsody, which integrates sequence evolution and known structure-based data, to predict the pathogenicity of saturating missense variants in genes that encode the major subunits of GABAA receptors in the central nervous system, including GABRA1, GABRB2, GABRB3, and GABRG2. Our results demonstrate that the predicted pathogenicity correlates well between AlphaMissense and Rhapsody although AlphaMissense tends to generate higher pathogenic probability. Furthermore, almost all annotated pathogenic variants in the ClinVar clinical database are successfully identified from the prediction, whereas uncertain variants from ClinVar partially due to the lack of experimental data are differentiated into different pathogenicity groups. The pathogenicity prediction of GABAA receptor missense variants provides a resource to the community as well as guidance for future experimental and clinical investigations.

biochemistry↗

Pharmacological chaperones restore proteostasis of epilepsy-associated GABAA receptor variants

Recent advances in genetic diagnosis identified variants in genes encoding GABAA receptors as causative for genetic epilepsy. Here, we selected eight disease-associated variants in the 1 subunit of GABAA receptors causing mild to severe clinical phenotypes and showed that they are loss of function, mainly by reducing the folding and surface trafficking of the 1 protein. Furthermore, we sought client protein-specific pharmacological chaperones to restore the function of pathogenic receptors. Applications of positive allosteric modulators, including Hispidulin and TP003, increase the functional surface expression of the 1 variants. Mechanism of action study demonstrated that they enhance the folding and assembly and reduce the degradation of GABAA variants without activating the unfolded protein response in HEK293T cells and human iPSC-derived neurons. Since these compounds cross the blood-brain barrier, such a pharmacological chaperoning strategy holds great promise to treat genetic epilepsy in a GABAA receptor-specific manner.

cell biology↗

Adapting the endoplasmic reticulum proteostasis rescues epilepsy-associated NMDA receptor variants

The GRIN genes encoding N-methyl-D-aspartate receptor (NMDAR) subunits are remarkably intolerant to variation. Many pathogenic NMDAR variants result in their protein misfolding, inefficient assembly, reduced surface expression, and impaired functionality at the plasma membrane, causing neurological disorders including epilepsy and intellectual disability. Here, we concentrate on the proteostasis maintenance of NMDARs containing epilepsy-associated variations in the GluN2A (or NR2A) subunit, including M705V and A727T. We showed that these two variants are targeted to the proteasome for degradation and have reduced functional surface expression. We demonstrated that the application of BIX, a known small molecule activator of an HSP70 family chaperone BiP (Binding immunoglobulin Protein) in the endoplasmic reticulum (ER), significantly increases total and surface protein levels, and thus the function of the M705V and A727T variants in HEK293T cells. Mechanistic studies revealed that BIX promotes folding, inhibits degradation, and enhances anterograde trafficking of the M705V variant by modest activation of the IRE1 pathway of the unfolded protein response. Our results showed that adapting the ER proteostasis network restores the folding, trafficking, and function of pathogenic NMDAR variants, representing a potential treatment for neurological disorders resulting from NMDAR dysfunction.

cell biology↗

Vaccinia virus induces EMT-like transformation and RhoA-mediated mesenchymal migration

The emerging outbreak of monkeypox is closely associated with the viral infection and spreading, threatening global public health. Virus-induced cell migration facilitates viral transmission. However, high-resolution dynamics and mechanisms underlying this type of cell migration remain unclear. Here, we investigate the motility of cells infected by vaccinia virus (VACV), a close relative of monkeypox, through combining multi-omics analyses and high-resolution live-cell imaging. We find that, upon VACV infection, the epithelial cells undergo EMT-like transformation, during which they lose intercellular junctions and acquire the migratory capacity to promote viral spreading. After transformation, VACV-induced mesenchymal migration is highly dependent on the actin cytoskeleton and RhoA signaling, which is responsible for the depolymerization of robust actin stress fibers, the leading-edge protrusion formation, and the rear-edge recontraction. Our study reveals how poxviruses alter the epithelial phenotype and regulate RhoA signaling to induce fast migration, providing a unique perspective to understand the pathogenesis of poxviruses.

cell biology↗

Hsp47 Promotes Biogenesis of Multi-subunit Neuroreceptors in the Endoplasmic Reticulum

Protein homeostasis (proteostasis) deficiency is an important contributing factor to neurodegenerative, neurological, and metabolic diseases. However, how the proteostasis network orchestrates the folding and assembly of multi-subunit membrane proteins is not well understood. Previous proteomics studies identified Hsp47 (Gene: SERPINH1), a heat shock protein in the endoplasmic reticulum lumen, as the most enriched interacting chaperone for gamma-aminobutyric type A (GABAA) receptors. Here, we show that Hsp47 enhances neuronal GABAA receptor functional surface expression, acting after Binding immunoglobulin Protein (BiP) to preferentially bind the folded conformation of GABAA receptors. Therefore, Hsp47 promotes the subunit-subunit interaction, the receptor assembly process, and the anterograde trafficking of GABAA receptors. These Hsp47 properties are also extended to other Cys-loop receptors, including nicotinic acetylcholine receptors. Therefore, in addition to its known function as a collagen chaperone, this work establishes that Hsp47 also plays a critical and general role in the maturation of multi-subunit neuroreceptors. HighlightsO_LIHsp47 positively regulates the functional surface expression of endogenous GABAA receptors. C_LIO_LIHsp47 acts after BiP and preferentially binds the folded conformation of GABAA receptors. C_LIO_LIHsp47 promotes the subunit-subunit assembly of GABAA receptors. C_LIO_LIHsp47 plays a critical and general role in the maturation of multi-subunit neuroreceptors. C_LI

cell biology↗

Microsecond pulse electrical stimulation modulates cell migration

Wound healing is a complicated process for maintaining skin integrity after injury, for which electrical stimulations (ES) are ascribed to promote wound healing by facilitating cell migration. Time-shortening of the stimulation treatment from current hours to minutes for efficient wound healing but free of cell damage in return, is however rather a challenge. Here, a novel mechanism of ultrashort pulse electric field (PEF), microsecond PEF at higher voltage, is proposed and realized to promote wound healing under a much short time (seconds) for the total treatment. We revealed that microsecond PEF regulated actin cytoskeleton reorganization and focal adhesion turnover, promoting fibroblasts migration in 2D cell cultures under the pulse stimulation. This accelerated fibroblast migration was accompanied by the mutual promotion with extracellular matrix (ECM) alignment in 3D microenvironments, which cooperatively benefit the eventual wound healing, and these findings were further confirmed by the enhanced skin wound healing in a classic mouse model. Additionally, we coined an actin- and collagen-dependent mechanism of microsecond PEF-mediated wound healing. The quantitative mechanism proposed here for our novel microsecond pulse electric filed (sPEF) methodology orients the new practical electric treatment in a wide range of biomedical applications, such as wound healing, regenerative medicine, and tissue engineering.

bioengineering↗