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Biology subjects

Pan, G.

Publications and source records attributed to Pan, G..

At least 19 recordsLinked to original sources

From sensation to action: distributed mesoscale dynamics in the primate brain

Perceptual decisions engage distributed brain networks, yet how decision-related signals are organized across and within brain areas remains unclear. Mesoscale functional domains are established in visual cortex, but whether spatially distinct domains organize perceptual decisions across the brain is unknown. Here we used 7-T functional MRI at 1-mm isotropic resolution in two awake macaques performing a contrast-discrimination task to map brain-wide activity during sensation, decision formation and saccadic report. Voxel timecourses separated into three groups with distinct temporal profiles, associated with sensory, decision-related and action-related activity. Their spatial distributions formed a broad progression from visual cortex to parietal, prefrontal and motor regions, while revealing distinct response domains within these regions. Choice-related signals were distributed across sensory, associative, and motor systems before movement, including in visual cortex responses to physically identical stimuli that differed according to the animal's eventual choice. Moreover, within the intraparietal sulcus and other regions, mesoscale domains preferentially responsive to near-threshold conditions carried choice information under uncertainty, whereas domains responsive to high-contrast conditions carried choice information when evidence was strong. These findings reveal that perceptual decisions are organized across the brain through spatially differentiated mesoscale networks whose activity varies with task phase and sensory certainty. This spatial organization provides a framework for investigating how distributed neural signals support flexible choice.

neuroscience↗

Regulatory-scale stripe analysis from single-cell Hi-C with scStripe

Chromatin stripes are a directional architectural feature of three-dimensional genome organization, but their analysis in single-cell Hi-C (scHi-C) at regulatory resolution is hindered by extreme sparsity. We developed scStripe, an imputation-free two-stage statistical framework that detects stripes from sparse cell-type--aggregated scHi-C maps and directly quantifies the resulting aggregate-defined stripes in raw individual-cell contact maps using per-cell stripe scores. Across three complementary benchmark settings, scStripe achieved the highest F1 scores and showed strong aggregate stripe enrichment, while the detected stripes recapitulated characteristic structural and regulatory features reported in bulk data. Per-cell stripe scores resolved recurrent configurations of the EBF1-anchored stripe, captured genome-wide variation associated with cell type, cell-cycle phase, and developmental stage, and identified positively associated gene--stripe pairs with pronounced cell-type specificity using matched scRNA-seq. Together, scStripe provides a practical, scalable framework for regulatory-scale stripe analysis across single cells without requiring single-cell enhancement or 3D reconstruction.

genetics↗

Decoding the oxytocinergic and behavioral signatures of milk ejection

Oxytocin-mediated milk ejection (ME) is pivotal to effective breastfeeding and productive health, yet behaviorally decoding and revealing neural mechanisms of ME remains challenging. Here, we combined in vivo calcium imaging and intramammary pressure recording to uncover the temporal connections between episodic activity of oxytocin neurons and ME in conscious lactating rats. Leveraging the association and behavioral responses in dam and pup, we developed a supervised machine learning framework (ME Decoder) to enable automated analyses of ME. Inspired by its interpretable features, we defined the activity-coupled dam-pup interactions (ADPI), manifested by high kyphosis of the dam followed by pup treading and stretch, as the behavioral signatures of ME. By ME Decoder and ADPI analyses, we detected reduced ME but unaffected activity of oxytocinergic neurons after systemic blockade of oxytocin receptor. Our study uncovers the oxytocinergic and behavioral signatures of ME and provides a generalizable approach for further investigation.

neuroscience↗

Most inhibitors with defined yeast targets have limited activity against the microsporidian Nematocida parisii

Microsporidia are obligate intracellular parasites that infect diverse animals. Budding yeast has long been used to define core molecular pathways and inhibitors that target them. To test whether these compounds can target conserved pathways in the microsporidian Nematocida parisii, we assessed 15 inhibitors with defined yeast targets that had not previously been tested for effects on infection of Caenorhabditis elegans. Most showed little activity against N. parisii, except tunicamycin. These results identify tunicamycin as a potential tool for studying endoplasmic reticulum stress in microsporidia, while indicating that most yeast-targeted inhibitors are largely ineffective in this system.

microbiology↗

Candida albicans reprograms host inosine metabolism to drive immunosuppressive macrophage polarization and gastric cancer carcinogenesis

Gastric cancer (GC) is strongly associated with changes in the gastric microbiome. However, the direct contribution of individual pathogenic species to tumor initiation and progression remains poorly defined. Here, we identified Candida albicans (C. albicans), a fungus that ranks as the most significantly enriched taxon in GC tissues, can directly promote gastric carcinogenesis. We found that when C. albicans alone was colonized into the gastric mucosa of mice, it induced the complete sequence of GC-associated preneoplastic lesions, including chronic gastritis, mucinous metaplasia, and atypical hyperplasia, with 16% of colonized animals progressing to low-grade intraepithelial dysplasia. In K19-C2mE transgenic mice, a model of spontaneous GC formation, infection with C. albicans significantly accelerated GC formation, with synergistic effects observed upon co-infection with the well-known gastric carcinogen, Helicobacter pylori. Mechanistically, C. albicans upregulated inosine levels in both gastric tissues and circulation. This inosine promoted polarization of macrophages toward an M2-like phenotype by activating the adenosine A2a receptor (A2aR), creats an immunosuppressive microenvironment that protects GC cells from the tumoricidal effects of anti-tumor immunity. Depletion of M2 macrophages or pharmacological inhibition of A2aR attenuated C. albicans-mediated tumorigenesis. Clinically, elevated inosine levels correlated with prior C. albicans exposure and poorer outcomes of GC patients. Our findings establish C. albicans as a direct pro-tumorigenic pathogen in GC and highlight the inosine-A2aR-M2 macrophage axis as a promising target for therapeutic intervention.

cancer biology↗

Forward genetics reveals microsporidian drug targets and recombination-based resistance

Microsporidia are a diverse group of intracellular fungal parasites that infect humans and many agriculturally important animals. Several microsporidia inhibitors have been characterized, but the targets of these inhibitors in microsporidia have not been confirmed, and the mechanisms by which microsporidia evolve resistance are unknown. Using the model organism Caenorhabditis elegans and its naturally occurring microsporidian parasite Nematocida parisii, we developed a technique to continually passage infected animals for multiple generations under increasing inhibitor concentrations. We obtained multiple independent N. parisii strains that are specifically resistant to the microsporidia inhibitors albendazole or dexrazoxane. The albendazole-resistant strains all contained either heterozygous or homozygous mutations in beta-tubulin, with several strains containing beta-tubulin variants that have been observed in other albendazole-resistant organisms. Strains containing homozygous variants are resistant to several albendazole analogs, whereas the heterozygous variant-containing strains are only resistant to albendazole. Several of the albendazole-resistant strains also contain mutations in alpha-tubulin. The dexrazoxane-resistant strains all contain heterozygous mutations in topoisomerase II and several of these mutations occur in the binding site of this inhibitor. By mapping heterozygosity of the resistant strains across the N. parisii genome, we observed loss of heterozygosity spanning the beta-tubulin locus in the albendazole-resistant strains containing homozygous beta-tubulin variants. Our study demonstrates the utility of forward genetics for identifying microsporidian drug targets. We also find that drug resistance arises through de novo heterozygous mutations that can subsequently become homozygous, likely via mitotic recombination.

microbiology↗

Cross-task, explainable, and real-time decoding of human emotion states by integrating grey and white matter intracranial neural activity

Decoding human emotion states from intracranial neural activity is key in developing brain-computer interfaces and new therapies for affective disorders. However, real-world application of decoding requires high performance that integrates neural activity from both grey and white matter, stable generalization across different contexts, sufficient neural encoding explainability, and robust real-time implementation, all of which remain elusive. Here, we simultaneously recorded intracranial electroencephalogram (iEEG) and abundant self-rated valence and arousal scores across two emotion-eliciting tasks in eighteen subjects, forming the largest intracranial neural dataset for emotion decoding. We then developed personalized decoding models within a hybrid deep learning framework involving both self-supervised and supervised components. The models achieved high-performance decoding of continuous valence/arousal states, doubling the R-squared performance of prior EEG/iEEG decoding. Critically, the models significantly improved performance by integrating grey and white matter signals and demonstrated cross-task generalization. The models further revealed shared and preferred mesolimbic-thalamo-cortical subnetworks encoding valence and arousal, showing neurophysiological explainability. Finally, the models realized robust real-time decoding in four new subjects. Our results have implications for advancing emotion decoding neurotechnology toward deployable affective brain-computer interfaces and closed-loop therapeutic systems for affective disorders.

neuroscience↗

Identification of natural products and synthetic analogs which inhibit microsporidia spores and prevent infection

Microsporidiosis, a disease caused by microsporidia, affects many animals, with symptoms ranging from diarrhea to death, especially in immunocompromised individuals. Current treatments, such as albendazole and fumagillin, are limited in efficacy. To address this problem, we utilized Caenorhabditis elegans infected with its natural microsporidian Nematocida parisii to evaluate 4,080 structurally diverse compounds from the Boston University Center for Molecular Discovery (BU-CMD) chemical library. From this screen we identified 34 compounds that effectively inhibited N. parisii infection and restored the reproductive capacity of C. elegans. All 17 compounds we validated prevented N. parisii infection in C. elegans, and 10 were capable of suppressing microsporidia invasion by inactivating mature spores. Additionally, five of the identified compounds were also effective against Pancytospora epiphaga, a species related to human-infecting microsporidia. Together this work identifies and characterizes compounds which inhibit microsporidia infection. ImportanceMicrosporidia are a large group of microbial parasites that infect many animals, including humans. Many agriculturally important animals such as honey bees, shrimp, crabs, and fish are infected by microsporidia, and these infections often result in smaller animals, fewer offspring, and death. Only two drugs are commonly used to treat microsporidia infections; due to some species being resistant and host toxicity there is a need to identify other microsporidia inhibitors. In this study, we screened over 4000 small molecules using a model round worm infected with microsporidia. We identified several dozen inhibitors and characterized how these compounds prevented infection by determining which stage of the parasite they act upon. Together our work identified and characterized compounds that could be used as a starting point to design better microsporidia inhibitors.

microbiology↗

Molecular dynamics driving phenotypic divergence among KRAS mutants in pancreatic tumorigenesis

Inflammation in the pancreas drives acinar-to-ductal metaplasia (ADM), a progenitor-like state that can be hijacked by mutant Kras in the formation of pancreatic cancer (PDAC). How these cell fate decisions vary according to KRAS mutation remains poorly understood. To define mutation-specific lineage reversion and tumor initiation, we implement novel Ptf1a-TdTomato mice and multiple KRAS mutants across an array of genetic, pharmacologic, and inflammatory perturbations in vivo. Whereas KRASG12D co-opts injury to enable lineage reversion, enhancer reprogramming, and tumor initiation, KRASG12R/V can initiate but not sustain dedifferentiated and neoplastic transcriptional and epigenetic programs. We find the KRASG12R/V defects consist of a failure to invoke robust EGFR signaling and activate Rac1/Vav1, with constitutive Akt activation in vivo sufficient to rescue the tumorigenic potential of KRASG12R. As the marked heterogeneity among KRAS variants begins early in tumorigenesis, these data are crucial to understanding mutation-specific oncogenic trajectories and directing the implementation of KRAS-directed therapeutics. SIGNIFICANCEDefining how KRAS mutants drive distinct outcomes in human pancreatic cancer is critical for developing allele-specific therapeutic approaches. This study unveils a hierarchy among KRASG12D, KRASG12V, and KRASG12R to drive tumor initiation, owing to heterogeneous activation of EGFR, PI3K/AKT, and RAC1 signaling, thus revealing mutation-specific evolutionary paths in pancreatic tumorigenesis.

cancer biology↗

RIP2 inhibits DOCK8-mediated platelet dense granule release and alleviates experimental myocardial infarction

ObjectiveReceptor-interacting protein 2 (RIP2) is an essential mediator of inflammation and innate immunity downstream of pattern recognition receptors (PRRs). Platelets express RIP2, while its role in platelet activation, thrombosis, and myocardial infarction (MI) is unknown. Approach and ResultsHere we show that RIP2 deficiency enhances platelet dense granule secretion in response to GPIb and GPVI activation; platelet aggregation in whole blood and adhesion under arterial shear are also increased. Consistently, RIP2 inhibitor WEHI-345 potentiates human platelet dense granule secretion and inhibits RIP2 phosphorylation induced by thrombin and collagen. These phenotypes are translated into shorter bleeding time, accelerated FeCl3-induced arterial thrombosis. Importantly, platelets from patients with coronary artery disease and mice with atherosclerosis express lower RIP2, and RIP2 deficiency deteriorates MI and cardiac function in a mouse ischemia/reperfusion model. Mechanistically, we found that platelets express dedicator of cytogenesis protein 8 (DOCK8), which is sequestered by phosphorylated RIP2 (p-RIP2), causing inhibition of Cdc42 activation and subsequent dense granule release. ConclusionsIn conclusion, RIP2 inhibits platelet activation, thrombosis, and ameliorates MI. Our results also suggest that a novel PRR-independent pathway, p-RIP2-DOCK8-Cdc42, negatively regulates platelet activation downstream of GPIb and GPVI. Platelet RIP2 pathway may be promising for therapeutic intervention of atherothrombotic diseases from early atherosclerosis stage to arterial thrombosis and MI. HighlightsO_LIRIP2 inhibits platelet dense granule release NOD2-independenly via pRIP2-DOCK8-Cdc42. C_LIO_LIThe negative regulation of RIP2 on platelet activation is translated into enhanced thrombosis, exacerbated myocardial infarction (MI). C_LIO_LIRIP2 pathway booster may be an approach for therapeutic intervention of atherothrombotic diseases. C_LI

molecular biology↗

Small-molecule screen in C. elegans identifies benzenesulfonamides as inhibitors of microsporidia spores

Microsporidia, a large group of fungal-related intracellular parasites, infect several economically significant animals, leading to substantial economic losses. As currently available anti-microsporidia therapies are either ineffective or come with numerous adverse effects, there is a need for alternative microsporidia inhibitors. Here we screen a subset of the ChemBridge DIVERset library, comprising 2500 diverse compounds, using Caenorhabditis elegans infected with its natural microsporidian parasite, Nematocida parisii. By testing these compounds at 60 M in 96-well assay plates, we identified 26 hits that restored the ability of C. elegans to produce progeny in the presence of N. parisii. We confirmed that out of 20 tested compounds, 18 ChemBridge compounds effectively inhibit N. parisii infection in C. elegans. Of these 18, 10 were benzenesulfonamide derivatives which inhibit microsporidia infection by inactivating spores. We screened an additional 475-compound benzenesulfonamide library, successfully identifying three compounds that are effective at a lower concentration than the initial hits. We further show that one benzenesulfonamide compound displays inhibitory activity against several species of microsporidia, inhibiting infection of species belonging to the Nematocida, Enterocytozoon, and Encephalitozoon genera. Together our results suggest that benzenesulfonamides are a potential scaffold for the development of microsporidia antiseptics.

microbiology↗

ldentify potential feature genes and immune cell infiltration of HIRI based on branched-chain amino acid-related genes by machine learning and experimental validation

BackgroundBranched-chain amino acid metabolism is involved in the pathogenesis of various liver diseases. In this study, we investigate the potential role of branched-chain amino acid metabolism-related genes in the pathogenesis of hepatic ischemia reperfusion (HIRI). MethodsThe gene Expression profiles of HIRI were obtained from the Gene Expression Omnibu database. To determine the differential expression of branched-chain amino acid metabolism-related genes between HIRI and normal tissues. Then, the GO and KEGG analyses were performed, and the protein-protein interaction network was constructed. Next, the random forest and LASSO algorithms were used to screen hub genes, and machine learning techniques were used to build diagnostic models. immunoinfiltration was analyzed in both HIRI patients and controls and the ceRNA network was established. Finally, quantitative real-time PCR was used to verify the expression of hub gene. ResultsBased on data set GSE23649, three central DEGs (SLC7A5, SLC1A5, SLC43A2) were determined by the intersection of three machine learning algorithms and used to establish a nomogram that yielded a high predictive performance (area under the curve 0.733-0.922). In the external GSE15480 dataset, AUC value for three key genes is as high as 1.000. Further analysis of nomogram, decision curve and calibration curve also confirme the predictive efficacy of diagnosis. GSEA and GSVA suggest that these three marker genes were involved in multiple pathways associated with HIRI progression. Immunoinfiltration analysis suggest that the proportion of macrophages, neutrophils, aDCs, Treg, and Th1 cells in HIRI group is higher than that in control group, with statistical significance(P<0.05). The ceRNA network demonstrates the complex regulatory relationships among the three hub genes and these mRNA levels were further confirmed in mouse HIRI liver samples. ConclusionsOur study have provided a comprehensive understanding of the association between branched-chain amino acid and HIRI, may provide potential target for HIRI treatment and diagnosis. And provide new insights into the mechanisms of HIRI. Graphical Abstract

bioinformatics↗

TRAIT: A Comprehensive Database for T-cell Receptor-Antigen Interactions

Comprehensive and integrated resources on interactions between T-cell receptors and antigens are still lacking for adoptive T-cell-based immunotherapies, highlighting a significant gap that must be addressed to fully comprehend the mechanisms of antigen recognition by T-cells. In this study, we present TRAIT, a comprehensive database that profiles the interactions between T-cell receptors (TCRs) and antigens. TRAIT stands out due to its comprehensive description of TCR-antigen interactions by integrating sequences, structures and affinities. It provides nearly 8 million experimentally validated TCR-antigen pairs, resulting in an exhaustive landscape of antigen-specific TCRs. Notably, TRAIT emphasizes single-cell omics as a major reliable data source for TCR-antigen interactions and includes millions of reliable non-interactive TCRs. Additionally, it thoroughly demonstrates the interactions between mutations of TCRs and antigens, thereby benefiting affinity maturation of engineered TCRs as well as vaccine design. TCRs on clinical trials were innovatively provided. With the significant efforts made towards elucidating the complex interactions between TCRs and antigens, TRAIT is expected to ultimately contribute superior algorithms and substantial advancements in the field of T-cell-based immunotherapies. TRAIT is freely accessible at https://pgx.zju.edu.cn/traitdb.

immunology↗

ER stress-induced TREM2 downregulation exacerbates platelet activation and myocardial infarction in patients with coronary artery disease

Coronary artery disease (CAD) is characterized by the chronic immune-inflammation, excessive endoplasmic reticulum (ER) stress, and platelet hyperactivity; however, whether there is a signaling hub linking these events remains unclear. Here, we identified that triggering receptor expressed on myeloid cells 2 (TREM2), an important pattern recognition receptor of the innate immune system, may serve as one such hub. We found that platelets expressed TREM2 and platelets from CAD patients had decreased TREM2 expression compared to healthy subjects. Decreased TREM2 is associated with platelet hyperactivity in CAD patients. This decrease could be due to excessive ER stress, which downregulated TREM2 through the CHOP-C/EBP axis. Loss of TREM2 not only enhanced platelet activation in response to ADP, collagen, and collagen-related peptide (CRP), but also amplified the platelet inflammatory response. Loss of TREM2 exacerbated mouse mesenteric arterial thrombosis and aggravated experimental myocardial infarction (MI). Moreover, a TREM2-activating antibody inhibited platelet activation, alleviated arterial thrombosis and pulmonary embolism. In addition, TREM2-activating antibody exhibited cardioprotective roles against experimental MI and reduced the inflammatory burden. Mechanistically, TREM2/DAP12/SHIP1 axis negatively regulated platelet activation through reducing PIP3 levels and inhibiting Akt phosphorylation. We also provided evidence supporting sphingosine-1-phospage (S1P) as a physiological agonist of TREM2. In summary, we find that TREM2 connects chronic immune-inflammation, excessive ER stress, and platelet hyperactivity in CAD patients. Downregulating TREM2 by ER stress exacerbates platelet activation and amplifies inflammation response in patients with CAD. TREM2-activating antibodies may have therapeutic potential for CAD patients. Key PointsO_LIPlatelets from CAD patients have decreased TREM2 expression, which is caused by ER stress and associated with platelet hyperactivity. C_LIO_LIS1P-TREM2-SHIP1 pathway inhibits platelet activation, alleviates arterial thrombosis, and exhibits cardioprotective roles against experimental myocardial infarction. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=88 SRC="FIGDIR/small/608887v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@1e21f2eorg.highwire.dtl.DTLVardef@6d427forg.highwire.dtl.DTLVardef@128af74org.highwire.dtl.DTLVardef@16f48c_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOVisual Abstract.C_FLOATNO Downregulation of platelet TREM2 caused by ER stress in CAD patients leads to platelet hyperactivity and aggravates myocardial ischemia, which is rescued by TREM2-activating antibody. Excessive ER stress in CAD upregulates CHOP, which dimerizes with C/EBP, a transcription factor of TREM2, decreases TREM2 transcription and expression in megakaryocytes and further in platelets. TREM2/DAP12/SHIP1/Akt pathway negatively regulates platelet activation; decreased TREM2 thus aggravates platelet hyperactivity, inflammation, and myocardial infarction, which can be rescued by TREM2 activation including antibody or the small molecule agonist. Physiologically, S1P released from platelet granules is an endogenous agonist of TREM2. C_FIG

pharmacology and toxicology↗

Microsporidian Nosema bombycis secretes serine protease inhibitor to suppress host cell apoptosis via caspase BmICE

Microsporidia are a group of intracellular pathogens that actively manipulate host cell biological processes to facilitate their intracellular niche. Apoptosis is an important defense mechanism by which host cell control intracellular pathogens. Microsporidia modulating host cell apoptosis has been reported previously, however the molecular mechanism is not yet clear. In this report, we describe that the microsporidia Nosema bombycis inhibits apoptosis of Bombyx mori cells through a secreted protein NbSPN14, which is a serine protease inhibitor (Serpin). An immunofluorescent assay demonstrated that upon infection with N. bombycis, NbSPN14 was initially found in the B. mori cell cytoplasm and then became enriched in the host cell nucleus. Overexpression and RNA-interference (RNAi) of NbSPN14 in B. mori embryo cells confirmed that NbSPN14 inhibited host cell apoptosis. Immunofluorescent and Co-IP assays verified the co-localization and interaction of NbSPN14 with the BmICE, the caspase 3 homolog in B. mori. Knocking out of BmICE or mutating the BmICE-interacting P1 site of NbSPN14, eliminated the localization of NbSPN14 into the host nucleus and prevented the apoptosis-inhibiting effect of NbSPN14, which also proved that the interaction between BmICE and NbSPN14 occurred in host cytoplasm and the NbSPN14 translocation into host cell nucleus is dependent on BmICE. These data elucidate that N. bombycis secretory protein NbSPN14 inhibits host cell apoptosis by directly inhibiting the caspase protease BmICE, which provides an important insight for understanding pathogen-host interactions and a potential therapeutic target for N. bombycis proliferation. Author SummaryMicrosporidia constitute a class of eukaryotic pathogens that exclusively reside within host cells. The species Nosema bombycis is the first microsporidian identified as the pathogen of silkworm Pebrine disease. In our research, we discovered how N. bombycis cleverly evades the hosts defenses. It has developed a strategy to survive inside host cells by manipulating host cell apoptosis, disarming the host cells self-destruct mechanism. In this study, we discovered that the N. bombycis secretes a serine protease inhibitor named NbSPN14, which infiltrates the cytoplasm of the host cell. The NbSPN14 interacts with the executioner Caspase protease BmICE within the silkworms apoptotic pathway, effectively neutralizing its apoptoic activity and thus curbing the apoptosis of the host cells.

microbiology↗

Tri-omic mapping revealed concerted dynamics of 3D epigenome and transcriptome in brain cells

Exploring the genomic basis of transcriptional programs has been a longstanding research focus. Here, we report a high-throughput single-cell tri-omic method to capture chromatin accessibility, interaction, and RNA simultaneously (ChAIR). After validating in cultured cells, we applied ChAIR to brain cells across mouse lifespan and delineated the concerted dynamics of 3D-epigenomic architecture and transcription during maturation and aging. Particularly, ultra-long chromatin megacontacts and promoter-associated 3D-epigenomic states are effective in defining cell identity and revealing spatially-resolved anatomic specificity. Importantly, we found that neurons in different brain regions and non-neuronal cells may undergo divergent genomic mechanisms during differentiation and aging. Our results demonstrated ChAIRs robustness of connecting chromatin folding architecture with cellular property and its potential applications to address complex questions in single-cell resolution and spatial specificity.

genomics↗

CTCF mutation at R567 causes developmental disorders via 3D genome rearrangement and abnormal neurodevelopment

The three-dimensional genome structure organized by CTCF is required for development. Clinically identified mutations in CTCF have been linked to adverse developmental outcomes. Nevertheless, the underlying mechanism remains elusive. In this investigation, we explored the regulatory roles of a clinically relevant R567W point mutation, located within the 11th zinc finger of CTCF, by introducing this mutation into both murine models and human embryonic stem cell-derived cortical organoid models. Mice with homozygous CTCFR567W mutation exhibited growth impediments, resulting in postnatal mortality, and deviations in brain, heart, and lung development at the pathological and single- cell transcriptome levels. This mutation induced premature stem-like cell exhaustion, accelerated the maturation of GABAergic neurons, and disrupted neurodevelopmental and synaptic pathways. Additionally, it specifically hindered CTCF binding to peripheral motifs upstream to the core consensus site, causing alterations in local chromatin structure and gene expression, particularly at the clustered protocadherin locus. Comparative analysis using human cortical organoids mirrored the consequences induced by this mutation. In summary, this study elucidates the influence of the CTCFR567W mutation on human neurodevelopmental disorders, paving the way for potential therapeutic interventions.

molecular biology↗

Unveiling interactions of spatial-temporal information in tactile motion perception

The intricate interplay of spatial and temporal information in tactile-motion perception remains elusive. Despite strides in decoding neural signals for direction, speed and texture in tactile perception, nuanced interactions persist as challenges. Addressing this, we investigated direction and speed tactile perception, exploring the intricate spatial-temporal dynamics. Psychophysical experiments manipulated direction and speed parameters using a laboratory-designed fingerpad ball-stimulator. A pivotal discovery includes quadrant-dependent anisotropic distortion in perceived motion direction, expanding the well-known notion of a specific preferred orientation. Spatial features primarily influence inherent responses, while temporal features impact stimulus-specific responses, shedding light on dynamic directional perception. The introduction of a psychometric function improved the modeling of tactile-motion speed perception, incorporating both linear and nonlinear components for a more accurate representation. This study provides intriguing insights into the neural mechanisms in tactile-motion perception, with potential applications for somatosensation in brain-machine interfaces. TeaserThis study unveils the intricate interplay of perceiving tactile motion, shedding light on the mysteries of tactile sensations.

neuroscience↗