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Zhao, Y.

Publications and source records attributed to Zhao, Y..

At least 361 records · Page 20Linked to original sources

The metabolic enzyme GYS1 condenses with NONO/p54nrb in the nucleus to spatiotemporally regulate glycogenesis and myogenic differentiation

Accumulating evidence indicates that metabolic enzymes can directly couple metabolic signals to transcriptional adaptation and cell differentiation. Glycogen synthase 1 (GYS1), the key metabolic enzyme for glycogenesis, is a nucleocytoplasmic shuttling protein compartmentalized in the cytosol and nucleus. However, the spatiotemporal regulation and biological function of nuclear GYS1 (nGYS1) microcompartments remain unclear. Here, we show that GYS1 dynamically reorganizes into nuclear condensates under conditions of glycogen depletion or transcription inhibition. nGYS1 complexes with the transcription factor NONO/p54nrb and undergoes liquid-liquid phase separation to form biomolecular condensates, leading to its nuclear retention and inhibition of glycogen biosynthesis. Compared to their wild-type littermates, Nono-deficient mice exhibit exercise intolerance, higher muscle glycogen content, and smaller myofibers. Additionally, Gys1 or Nono deficiency prevents C2C12 differentiation and cardiotoxin-induced muscle regeneration in mice. Mechanistically, nGYS1 and NONO co-condense with the myogenic transcription factor MyoD and preinitiation complex (PIC) proteins to form transcriptional condensates, driving myogenic gene expression during myoblast differentiation. These results reveal the spatiotemporal regulation and subcellular function of nuclear GYS1 condensates in glycogenesis and myogenesis, providing mechanistic insights into glycogenoses and muscular dystrophy.

cell biology↗

Follicular mural granulosa cells stockpile glycogen to fuel corpus luteum pre-vascularization

The corpus luteum (CL) arises from the luteinization of follicular granulosa cells (GCs) and theca cells, marked by rapid progesterone elevation and angiogenesis. Intriguingly, angiogenesis lags behind progesterone elevation, creating an avascular phase during which luteal cells must fuel intensive steroidogenesis without perfusion. How the avascular CL meets this energetic demand remains a mystery. Here, we reveal a novel cellular adaptive mechanism-GC energy storage (GCES)-that resolves this enigma. We demonstrate that upon luteinization initiation, GCs enter a metabolically quiescent state yet enhance glucose uptake via SLC2A1, converting the glucose into glycogen through the hCG (LH)-MAPK-RUNX1-Insulin signaling axis. Catabolism of this glycogen reserve supplies the energy required for the avascular CL, ensuring normal luteogenesis. GCES is evolutionarily conserved across species. Genetic or pharmacological disruption of GCES or glycogenolysis induces luteal insufficiency, whereas timely glucose administration enhances GCES, improving luteal function and optimize reproductive outcome in both mouse and ovine models. In human study, orally intake of glucose post-hCG significantly augments GCES and enhances progesterone production in women. These results advance luteal physiology by uncovering a universal reproductive principle with direct clinical implications.

developmental biology↗

Concurrent PIK3CA mutant drives cachexia through inflammatory signaling in EGFR mutant lung cancer

PIK3CA mutation is frequently concurrent with known oncogenic drivers such as EGFR mutation in lung cancer, raising an interesting question about its real function. Cachexia is a systemic disease involving complex interaction between primary tumors and distant organs, significantly contributing to cancer-related mortality. Through integrative study of genetically engineered mouse models (GEMMs) and clinical data, we find concurrent PIK3CA mutant preferentially drives cachexia in EGFR-mutant lung cancer, promoting malignant progression instead of cancer initiation. PIK3CA mutant-mediated cachexia could be overcome by osimertinib (Osi) treatment in Osi-sensitive GEMM. In contrast, chemotherapy, routinely used in clinic for those relapsed from Osi therapy, fails to ameliorate cachexia in Osi-resistant GEMM despite notable tumor suppression. PIK3CA mutant-driven cachexia is mediated through NF-{kappa}B activation and could be dampened by combined aspirin treatment. This work uncovers the biological function of PIK3CA mutant and mechanism behinds its clinical impacts, and proposes a potentially effective strategy for clinical management.

cancer biology↗

Autoantibody hotspots reveal origin and impact of immunogenic XIST ribonucleoprotein complex

Four out of five patients with autoimmune diseases are women. The XIST ribonucleoprotein (RNP) complex, comprising the female-specific long noncoding RNA XIST and over 100 associated proteins, may drive several autoimmune diseases that disproportionately affect women, who have elevated levels of autoantibodies against the XIST RNP. However, the structural distribution, potential origin, and clinical significance of XIST RNP autoantibodies remained unexplored. Here, we find that XIST RNP is associated with autoantigens associated with six female-biased autoimmune conditions. Mapping autoantibody targets to their occupancy sites on XIST shows that these autoantigens are concentrated at discrete "hotspots" along the XIST lncRNA, notably the A-repeat. Cell type-specific protein expression data nominated neutrophils as a predominant source of hotspot antigens, and we confirmed the presence of both XIST and hotspot antigens in neutrophil extracellular traps during NETosis, an immunogenic programmed cell death pathway triggered by neutrophil activation upon which neutrophils extrude their nuclear content. Furthermore, we found that levels of autoantibodies against a top hotspot antigen, SPEN, that binds the A-repeat, correlate with severe digital ischemia in systemic sclerosis in two independent cohorts. Together, these data show a plausible mechanism for the origin of AXA, guided by RNA structure and RNA-protein interactions, and show that antibodies to XIST RNP holds promise for disease endotyping and prognostication in female-biased autoimmune conditions. One Sentence SummaryNovel autoantibodies target hotspots on XIST ribonucleoprotein complex in female-biased autoimmune diseases.

immunology↗

circAβ-a RNA encoded Aβ175--the hidden driver of β-amyloid plaque formation and deposition in sporadic Alzheimer's disease.

Mechanisms that trigger A{beta} production in sporadic Alzheimers disease are still obscure. We recently reported the expression of a human circular RNA (circA{beta}-a) encoded A{beta} peptide precursor variant (A{beta}175). Presently, we demonstrated that AAV9 virus-expressed circA{beta}-a gave rise to extensive extracellular A{beta} plaque depositions and microglial activation in mouse brain; this recapitulates critical pathogenic hallmarks within a sporadic AD mouse model. Specifically developed antibodies detected robust endogenous A{beta}175 expression in HEK293 cells and hNSC-derived human neurons, underscoring the potential of A{beta}175 as a salient A{beta} precursor. Furthermore, we detected high levels of A{beta}175 oligomers in young-adult human brains. In intermediate and old-age human brain samples, accumulation of soluble A{beta}175 pentamers was reduced and A{beta}175 oligomers were components of most insoluble A{beta} plaques in older human brain. We propose a causal relationship between human circA{beta}-a RNA expression, dysregulation of A{beta}175 oligomer processing/aggregation and A{beta} plaque accumulation in sporadic AD.

neuroscience↗

Fast and accurate modeling of TCR-peptide-MHC complexes using tFold-TCR

Alpha-beta T cell receptor ({beta}TCR) recognition of peptide-major histocompatibility complexes (pMHCs) is a corner- stone of the adaptive immune system. Fast and accurate modeling of TCR-pMHC structures is crucial for understanding TCR recognition of pMHCs at the molecular level, which is essential for the development of TCR-based therapeutics and vaccines. Despite significant interest, this challenge remains unresolved due to the diversity of TCR-pMHC interactions and limited structural data. Here, we present tFold-TCR, a high-throughput, end-to-end universal model for predicting three-dimensional (3D) atomic-level structures of TCR-pMHC complexes, capable of predicting TCRs of different classes and MHC structures from diverse systems. tFold-TCR leverages a specially trained, protein-protein interaction-sensitive large protein language model to extract intra- and inter-chain residue contact information and evolutionary relationships, bypassing the need for multiple sequence alignment (MSA) searches. It also features innovative structure prediction and flexible docking modules to enhance accuracy, particularly for interacting contacts. Compared to existing methods, including AlphaFold-3, tFold-TCR demonstrates a 30.7% increase in prediction success rate evaluated by DockQ and is over 25 times faster. These advancements enable large-scale structural characterization of TCRs and their interactions with pMHCs. Utilizing this capability, we constructed TCRStructDB, the largest database of TCR-pMHC structures to date, encompassing 2.2 million TCRs, 0.8 million pMHCs, and 45,000 TCR-pMHC complexes. TCRStructDB provides unprecedented insights into one of the most diverse receptor-ligand interactions in biology.

bioinformatics↗

VZV gE Promotes STING Degradation via Midnolin-Proteasome Pathway to Inhibit cGAS-STING Signaling

Varicella-zoster virus (VZV) infects 85 million individuals annually and it is known for its intricate interplay with host cellular mechanisms, significantly impacting antiviral immune responses. Previous studies have highlighted the critical role of VZV glycoprotein E (gE) in virus-host interactions, but the precise mechanisms remain to be elucidated. Our results demonstrate that VZV gE interacts with STING, specifically through the gE (350-480aa) and STING (151-160aa) regions. This interaction predominantly involves incompletely glycosylated gE. Functional assays revealed that gE inhibits the cGAS-STING signaling pathway. gE enhances VZV proliferation and promotes STING degradation via the proteasome pathway, without affecting STING ubiquitination. We identified Midnolin as a mediator in this degradation process, with gE facilitating the interaction between STING and Midnolin. In vivo, gE expression in mice led to diminished antiviral responses upon HSV-1 infection, highlighting gEs role in modulating immune signaling. Our findings provide significant insights into VZVs evasion of host immune responses. By promoting STING degradation through an unconventional Midnolin-proteasome pathway, VZV gE effectively suppresses antiviral signaling, facilitating enhanced viral proliferation. The findings contribute significantly to the understanding of VZV pathogenesis and provide new therapeutic strategies against VZV.

microbiology↗

Identification and classification of abundant RNA-binding proteins in the mouse lens and interactions of Carhsp1, Igf2bp1/ZBP1, and Ybx1 with crystallin and β-actin mRNAs

RNA-binding proteins (RBPs) are critical regulators of mRNAs controlling all processes such as RNA transcription, transport, localization, translation, mRNA:ncRNA interactions, and decay. Cellular differentiation is driven by tissue-specific and/or tissue-preferred expression of proteins needed for the optimal function of mature cells, tissues and organs. Lens fiber cell differentiation is marked by high levels of expression of crystallin genes encoding critical proteins for lens transparency and light refraction. Herein we performed proteomic and transcriptomic analyses of RBPs in differentiating mouse lenses to identify the most abundant RBPs and establish dynamic changes of their expression in differentiating lens. Expression analyses include highly abundant RBPs, including Carhsp1, Igf2bp1/ZBP1, Ybx1, Pabpc1, Ddx39, and Rbm38. Binding sites of Carhsp1, Ybx1, and Igf2bp1/ZBP1 were predicted in various crystallin and {beta}-actin mRNAs. Immunoprecipitations using antibodies against Carhsp1, Igf2bp1/ZBP1, and Ybx1 confirmed their interactions with A-, B-, and {gamma}A-crystallin mRNAs. A combination of single molecule RNA FISH (smFISH) and immunofluorescence was used to probe in vivo interactions of these RBPs with A-, B-crystallin, and {beta}-actin mRNAs in cytoplasm and nucleoplasm of cultured mouse lens epithelial cells. Together, these results open new avenues to perform comprehensive genetic, cell, and molecular biology studies of individual RBPs in the lens.

developmental biology↗

VISTA-induced tumor suppression by a four amino acid intracellular motif

VISTA is a key immune checkpoint receptor under investigation for cancer immunotherapy; however, its signaling mechanisms remain unclear. Here we identify a conserved four amino acid (NPGF) intracellular motif in VISTA that suppresses cell proliferation by constraining cell-intrinsic growth receptor signaling. The NPGF motif binds to the adapter protein NUMB and recruits Rab11 endosomal recycling machinery. We identify and characterize a class of triple-negative breast cancers with high VISTA expression and low proliferative index. In tumor cells with high VISTA levels, the NPGF motif sequesters NUMB at endosomes, which interferes with epidermal growth factor receptor (EGFR) trafficking and signaling to suppress tumor growth. These effects do not require canonical VISTA ligands, nor a functioning immune system. As a consequence of VISTA expression, EGFR receptor remains abnormally phosphorylated and cannot propagate ligand-induced signaling. Mutation of the VISTA NPGF domain reverts VISTA-induced growth suppression in multiple breast cancer mouse models. These results define a mechanism by which VISTA represses NUMB to control malignant epithelial cell growth and signaling. They also define distinct intracellular residues that are critical for VISTA-induced cell-intrinsic signaling that could be exploited to improve immunotherapy.

cancer biology↗

In vitro evolution of caspofungin resistance in Candidozyma auris via FKS1 hotspot I mutations results in moderate fitness trade-offs but no reduction in virulence

Resistance to echinocandins in the recently emerged pathogen Candidozyma auris (previously known as Candida auris) poses significant clinical challenges. This study reports the in vitro evolution of a caspofungin-sensitive C. auris clade II isolate to acquire caspofungin resistance. We sequenced the whole genome of the parental strain and its drug-resistant progeny. The resistant isolates harboured mutations in the FKS1 gene altering a conserved residue (S639) also mutated in caspofungin-resistant clinical isolates; demonstrating that FKS1-S639 mutations are sufficient to confer resistance to caspofungin. Using these resistant strains, we examined cross-resistance & collateral sensitivity to other antifungal drugs and to cell wall stress, cell wall ultrastructure, biofilm formation, and virulence. As expected, both FKS1-S639P and FKS1-S639Y variants exhibited resistance not only to caspofungin but also to other echinocandins. Interestingly, these resistant strains showed moderate collateral sensitivity to certain azole antifungals and increased susceptibility to cell wall stress. While cell wall chitin content was slightly elevated in resistant isolates compared to sensitive ones, overall cell wall structure and phosphomannan levels remained unchanged. Biofilm formation capabilities were similar across all strains, and virulence in invertebrate models was unaffected by the FKS1 mutations. These findings indicate that while the evolution of caspofungin resistance through FKS1 mutations does incur fitness trade-offs, it does not substantially compromise the pathogenic potential of C. auris. This underscores the complexities of evolution of antifungal resistance mechanisms in this pathogen and the impact on its biology.

microbiology↗

ORP2 regulates free cholesterol accumulation in hepatocytes during MASH

BackgroundCholesterol crystals in hepatocytes are known to strongly associate with human Metabolic Dysfunction-Associated Steatohepatitis (MASH). However, it remains unclear which molecular pathway(s) regulates free cholesterol accumulation, and therefore the formation of cholesterol crystals in hepatocytes. In cultured cell lines, oxysterol-binding protein-related protein 2 (ORP2) functions to deliver cholesterol to the plasma membrane from internal organelles. MethodsHere, we generated liver-specific ORP2 knockout (ORP2-LKO) mice and characterized their metabolic phenotypes on chow and high fat diet. ResultsThe ORP2-LKO mice developed much more severe hepatic steatosis than wild type mice after high-fat diet feeding. They also demonstrated more severe liver inflammation and damage. Notably, free but not esterified cholesterol, as well as cholesterol crystals accumulated in ORP2-LKO liver. The expression of Cyp7a1 was significantly upregulated in ORP2-LKO liver, accompanied with accumulation of taurocholic acid. Our results thus unveil an important in vivo function of ORP2 in preventing free cholesterol from accumulating in mouse liver. Conclusionsour results suggest that impaired cholesterol trafficking may enhance the deposition of cholesterol crystals in hepatocytes, promoting the development of MASH.

cell biology↗

DNA supercoiling modulates eukaryotic transcription in a gene-orientation dependent manner

DNA supercoiling is an intrinsic consequence of transcription that must be resolved to maintain proper gene expression. How DNA supercoiling shapes transcription dynamics in chromatinized animal genomes remains unclear. Here, we acutely depleted topoisomerases I and II in Caenorhabditis elegans and applied nascent transcription profiling, nuclear and total RNA-seq, histone modification mapping, and long-read sequencing to capture the immediate transcriptional and chromatin responses to topological stress. We show that the genomic context influences the effect of supercoiling on transcription initiation, elongation and coordinated expression of adjacent genes. The impact of supercoiling on transcription initiation is not uniformly repressive but instead depends on the orientation and proximity of neighboring genes. We find that negative supercoiling promotes coordinated expression of divergent gene pairs, while positive supercoiling inhibits and uncouples expression of convergent genes. DNA supercoiling hinders transcription elongation globally resulting in reduced production of longer transcripts and overall shortening of poly(A) tails. While DNA supercoiling generated by neighboring transcription impacts initiation, elongation defects are driven by local supercoiling generated by the genes own transcription. These elongation effects are not accompanied by global changes in elongation-associated histone modifications but coincide with modest reductions in promoter and enhancer marks. Our findings reveal a directional mechanism by which genome architecture shapes transcriptional responses to DNA supercoiling, uncovering a DNA topological basis for coordinated gene expression in a multicellular organism.

molecular biology↗

Single-base m6A epitranscriptomics reveals novel HIV-1 host interaction targets in primary CD4+ T cells

N6-methyladenosine (m6A) is the most prevalent cellular mRNA modification and plays a critical role in regulating RNA stability, localization, and gene expression. m6A modification plays a vital role in modulating the expression of viral and cellular genes during HIV-1 infection. HIV-1 infection increases cellular RNA m6A levels in many cell types, which facilitates HIV-1 replication and infectivity in target cells. However, the function of m6A modification in regulating HIV-1 infection of primary CD4+ T cells remains unclear. Here, we demonstrate that HIV-1 infection of Jurkat CD4+ T cells and primary CD4+ T cells promotes the interaction between the m6A writer complex subunits methyltransferase-like 3 and 14 (METTL3/METTL14). Using single-base m6A-specific RNA sequencing, we identified several differentially m6A-modified cellular mRNAs, including perilipin 3 (PLIN3), during HIV-1 infection in primary CD4+ T cells. Interestingly, HIV-1 infection increased PLIN3 mRNA level by enhancing its stability, but PLIN3 protein level was decreased. Knocking down PLIN3 in primary CD4+ T cells reduced HIV-1 production but enhanced virion infectivity. In contrast, in Jurkat cells, PLIN3 mRNA and protein expression levels were unaffected by HIV-1 infection, and knocking out PLIN3 did not impact HIV-1 production or infectivity. These results indicate that the interplay between HIV-1 and PLIN3 is cell-type specific and only observed in primary CD4+ T cells. Overall, our results highlight the importance of m6A RNA modification in HIV-1-infected primary CD4+ T cells and suggest its significance as a regulatory mechanism in HIV-1 infection. Author SummaryN6-methyladenosine (m6A) is a common chemical modification on mRNA that helps control RNA stability, localization, and gene expression. m6A modification of viral and cellular RNA is important for HIV-1 infection. In this study, we found that HIV-1 infection of CD4+ T cells enhanced the interaction between two proteins, METTL3 and METTL14, which are responsible for adding m6A modifications to RNA. Using m6A-specific RNA sequencing, we identified several mRNAs with altered m6A modifications during HIV-1 infection, including one called PLIN3. Interestingly, HIV-1 infection stabilized and increased PLIN3 mRNA levels, but reduced PLIN3 protein expression in primary CD4+ T cells. When we knocked down PLIN3 in primary CD4+ T cells, it decreased HIV-1 production but made the HIV-1 particles more infectious. In contrast, in the Jurkat CD4+ T cell line, HIV-1 infection did not affect PLIN3 expression and knockout of PLIN3 did not alter HIV-1 production or infectivity, suggesting that the effect is specific to primary CD4+ T cells. Our findings show the importance of m6A RNA modification in HIV-1 infection by regulating host genes like PLIN3 and suggest a unique regulatory mechanism in HIV-1 infected primary CD4+ T cells.

microbiology↗

Nde1 Promotes Lis1 Binding to Full-Length Autoinhibited Human Dynein-1

Cytoplasmic dynein-1 (dynein) is the primary motor for the retrograde transport of intracellular cargoes along microtubules. The activation of the dynein transport machinery requires the opening of its autoinhibited Phi conformation by Lis1 and Nde1/Ndel1, but the underlying mechanism remains unclear. Using biochemical reconstitution and cryo-electron microscopy, we show that Nde1 significantly enhances Lis1 binding to autoinhibited dynein and facilitates the opening of Phi. We discover a key intermediate step in the dynein activation pathway where a single Lis1 dimer binds between the Phi-like (PhiL) motor rings of dynein. In this "PhiL-Lis1", Lis1 interacts with one of the motor domains through its canonical interaction sites at the AAA+ ring and stalk and binds to the newly identified AAA5, AAA6, and linker regions of the other motor domain. Mutagenesis and motility assays confirm the critical role of the PhiL-Lis1 interface. This intermediate state is instantly and efficiently formed in the presence of Nde1, but Nde1 is not part of the PhiL-Lis1. These findings provide key insights into the mechanism of how Nde1 promotes the Lis1-mediated opening of Phi dynein.

biophysics↗

McsB regulates CtsR thermosensing through periphery arginine phosphorylation

When cells sense an elevated temperature in the environment, the bacterial master transcription repressor CtsR becomes phosphorylated and inactivated by the arginine kinase McsB to initiate the expression of heat-shock genes. Here, we utilize a fluorescence intensity shift assay (FISA) based on the protein-induced fluorescence enhancement (PIFE) effect to monitor the DNA-CtsR-McsB interactions in real time. Our single-molecule analysis reveals that CtsR binds rapidly and stably to the cognate DNA, and that McsB is able to transiently interact with CtsR in situ of the target DNA. We determine the binding kinetics between McsB and the DNA-bound CtsR by single-molecule real-time binding assays, with kon and koff of 0.75 M-1 s-1 and 0.34 s-1, respectively. This interaction with McsB does not remove CtsR from the DNA, but lowers the temperature threshold for CtsR dissociation and alters its thermosensing behavior. Mass spectrometry, mutational analysis and structural simulation results together suggest that the phosphorylation of several periphery arginine residues on CtsR, which reduces the binding energy of the CtsR-DNA interaction, underlies a plausible molecular mechanism for this effect. Taken together, these results provide insights into how McsB regulates the CtsR-DNA complex and highlight the functional importance of CtsR periphery arginine residues in the bacterial heat-shock response.

biophysics↗

Systematic Benchmarking of High-Throughput Subcellular Spatial Transcriptomics Platforms

Recent advancements in spatial transcriptomics technologies have significantly enhanced resolution and throughput, underscoring an urgent need for systematic benchmarking. To address this, we collected clinical samples from three cancer types - colon adenocarcinoma, hepatocellular carcinoma, and ovarian cancer - and generated serial tissue sections for systematic evaluation. Using these uniformly processed samples, we generated spatial transcriptomics data across five high-throughput platforms with subcellular resolution: Stereo-seq v1.3, Visium HD FFPE, Visium HD FF, CosMx 6K, and Xenium 5K. To establish ground truth datasets, we profiled proteins from adjacent tissue sections corresponding to all five platforms using CODEX and performed single-cell RNA sequencing on the same samples. Leveraging manual cell segmentation and detailed annotations, we systematically assessed each platforms performance across key metrics, including capture sensitivity, specificity, diffusion control, cell segmentation, cell annotation, spatial clustering, and transcript-protein alignment with adjacent CODEX. The uniformly generated, processed, and annotated multi-omics dataset is valuable for advancing computational method development and biological discoveries. The dataset is accessible via SPATCH, a user-friendly web server for visualization and download (http://spatch.pku-genomics.org/).

genomics↗

Electron-density informed effective and reliable de novo molecular design and lead optimization with ED2Mol

Generative drug design opens new avenues for discovering novel compounds within the vast chemical space rather than conventional screening against limited compound libraries. However, the practical utility of the generated molecules is frequently constrained, as many designs prioritize a narrow range of pharmacological properties while neglecting physical reliability, which hinders the success rate of subsequent wet-lab evaluations. To address this, we propose ED2Mol, a deep learning-based approach that leverages fundamental electron density information to improve de novo molecular generation and lead optimization. The extensive evaluations across multiple benchmarks demonstrate that ED2Mol surpasses existing methods in terms of generation success rate and >97% physical reliability. It also facilitates automated lead optimization that is not fully implemented by other methods using fragment-based strategies. Furthermore, ED2Mol exhibits generalizability to more challenging, unseen allosteric pocket benchmarks, attaining consistent performance in both de novo molecule generation and lead optimization. More importantly, ED2Mol has been applied to various real-world essential targets, successfully identifying wet-lab validated bioactive compounds, ranging from FGFR3 orthosteric inhibitors to CDC42 allosteric inhibitors and GCK allosteric activators. The directly generated binding modes of these compounds with target proteins are close to predictions through molecular docking and further validated via the X-ray co-crystal structure. All these results highlight ED2Mols potential as a useful tool in realistic drug design with enhanced effectiveness, physical reliability, and practical applicability.

bioinformatics↗

Cortical connectivity, local dynamics and stability correlates of global conscious states

Consciousness emerges from complex neural processes, yet its precise neurobiological correlates remain uncertain. Here a space-time-resolved inference-based framework is applied to estimate the neurophysiological variables of a wholecortex model and analyze the neural mechanism correlates of global consciousness by way of a correlation analysis between behavioural and neural variable time-series. Using magnetoencephalography (MEG) data from 15 participants under Xenon-induced anesthesia, interconnected neural mass models (NMMs) were developed and time-evolving regional neurophysiological variables and inter-regional connectivity strengths were inferred from the data. Analyses revealed significant correlations between consciousness levels and inter-regional connectivity, particularly in posterior parietal, occipital, and prefrontal regions. Moreover, results support a parietal, rather than frontal, network backbone to facilitate global consciousness. Regional-level analyses further identified correlates of consciousness within the posterior parietal and occipital regions. Lastly, reductions in consciousness were linked to stabilized cortical dynamics, reflected by changes in the eigenmodes of the system. This framework provides a novel, inference-based approach to investigating consciousness, offering a time-resolved perspective on neural mechanism correlates during altered states.

neuroscience↗