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Miura, Y.

Publications and source records attributed to Miura, Y..

16 recordsLinked to original sources

Purinergic signaling promotes gliomagenesis through nuclear calcium transients

Intracellular Ca2+ transients drive key developmental and physiological processes, yet their role in oncogenesis remains incompletely understood. In glioblastoma (GBM), an aggressive brain malignancy, tumor cellular networks exhibit self-sustaining Ca2+ transients that promote tumor growth through unclear mechanisms. Using patient-derived GBM models, we show that these transients depend primarily on intracellular Ca2+ stores and extend to the nucleus to drive tumorigenesis. A neuromodulator screen identified extracellular purines ATP and ADP as potent inducers of both nuclear and cytosolic Ca2+ transients via activation of metabotropic purinergic P2RY1 receptors, whose knockdown attenuates tumorigenicity in vitro and in vivo. Mechanistically, Ca2+ transients promote tumorigenesis via the nuclear Ca2+/calmodulin-dependent kinase CAMK4, which regulates transcriptional and epigenetic programs, as well as ribosomal DNA transcription. From the therapeutic perspective, pharmacologic P2RY1 inhibition suppresses tumor growth in vitro and in vivo. Collectively, these findings reveal a pharmacologically targetable oncogenic mechanism in GBM and possibly other malignancies.

cancer biology↗

Sequentially Self-Assembled Supramolecular Nanocomplexes Enable Systemic Cas9 RNP Delivery and In Vivo Tumor Genome Editing

In vivo genome editing with CRISPR-Cas9 ribonucleoproteins (RNPs) holds substantial therapeutic promise, yet rapid bloodstream clearance and the absence of delivery systems capable of systemic tumor targeting have hindered its clinical translation. Herein, a supramolecular ternary complex platform is reported in which Cas9/sgRNA RNPs are co-assembled with tannic acid (TA) and phenylboronic acid (PBA)-conjugated polymers through sequential self-assembly, producing [~]30 nm core-shell ternary complexes that protect RNPs from enzymatic degradation and dissociate selectively at endosomal pH. Upon intravenous administration in subcutaneous tumor-bearing mice, these ternary complexes exhibit prolonged blood circulation and preferential tumor accumulation, achieving 37.2% gene editing at tumor sites compared with only 1.5% for free RNPs. The platform successfully knocks out previously undruggable oncogenes including mutant KRAS and polo-like kinase 1 (PLK1), markedly suppressing tumor growth in vivo. By integrating sequential supramolecular self-assembly with stimuli-responsive cargo release, this strategy establishes a generalizable framework for systemically administered in vivo CRISPR therapeutics.

bioengineering↗

Non-viral in vivo electroporation-based chromosomal engineering and repair assessment in the murine uterine epithelium

Withdrawal StatementThis manuscript has been withdrawn owing to a duplicate posting of manuscript number BIORXIV/2025/640089. This was a technical error for which the authors are not responsible, and this DOI for the work should not be cited as reference. The record is retained here for purposes of transparency. If you have any questions, please contact the corresponding author. The correct preprint can be found at doi: 10.1101/2025.02.25.640089.

genomics↗

Ubiquilin-2 liquid droplets catalyze α-synuclein fibril formation

Liquid-liquid phase separation (LLPS) and subsequent liquid-gel/solid transition are considered common aggregation mechanisms of proteins linked to neurodegenerative diseases. -synuclein (-syn), the main component of Parkinsons disease pathology, has been reported to undergo LLPS, thereby accelerating aggregate formation. However, the precise molecular events involved in the early stages of -syn aggregation remain controversial. In this study, we show that -syn aggregation is promoted by droplets formed by ubiquilin-2 (UBQLN2), rather than by -syn LLPS itself. During the liquid-gel/solid transition of UBQLN2 droplets, -syn within the droplets transformed into pathogenic fibrils both in vitro and in cells. Immunohistochemistry of brain sections from sporadic Parkinsons disease patients revealed UBQLN2 in substantia nigra Lewy bodies, implicating UBQLN2 in -syn aggregation in vivo. Furthermore, the small compound SO286 inhibited both UBQLN2 self-association and its interaction with -syn by binding to the STI1 domain, thereby suppressing -syn aggregation. These findings demonstrate that UBQLN2 droplets catalyze -syn fibrillization and suggest that small molecules targeting fibril-catalyzing proteins such as UBQLN2 may represent a novel therapeutic approach for neurodegenerative diseases.

biochemistry↗

In vivo electroporation-based chromosomal engineering in murine uterine epithelium

Clustered regularly interspaced palindromic repeat (CRISPR)/CRISPR-associated protein (Cas)-based in vivo chromosomal rearrangements are a promising approach for generating model organisms with specific chromosomal abnormalities. However, conventional in vivo methods rely on viral vectors, which are expensive, require specialized equipment, and pose potential safety risks, thereby limiting their widespread application. To overcome the limitations above, we developed a novel, efficient, and cost-effective in vivo chromosomal engineering strategy using CRISPR ribonucleoprotein electroporation for the murine uterine epithelium. Our method successfully induced translocations at multiple loci and repaired a 57.8-Mb inversion. The findings of the present study establish in vivo electroporation as a practical alternative to traditional chromosomal engineering methods and provide a foundation for its broader application in genome editing technologies.

genomics↗

Assembloid model to study loop circuits of the human nervous system

Neural circuits connecting the cerebral cortex, the basal ganglia and the thalamus are fundamental networks for sensorimotor processing and their dysfunction has been consistently implicated in neuropsychiatric disorders1-9. These recursive, loop circuits have been investigated in animal models and by clinical neuroimaging, however, direct functional access to developing human neurons forming these networks has been limited. Here, we use human pluripotent stem cells to reconstruct an in vitro cortico-striatal-thalamic-cortical circuit by creating a four-part loop assembloid. More specifically, we generate regionalized neural organoids that resemble the key elements of the cortico-striatal-thalamic-cortical circuit, and functionally integrate them into loop assembloids using custom 3D-printed biocompatible wells. Volumetric and mesoscale calcium imaging, as well as extracellular recordings from individual parts of these assembloids reveal the emergence of synchronized patterns of neuronal activity. In addition, a multi-step rabies retrograde tracing approach demonstrate the formation of neuronal connectivity across the network in loop assembloids. Lastly, we apply this system to study heterozygous loss of ASH1L gene associated with autism spectrum disorder and Tourette syndrome and discover aberrant synchronized activity in disease model assembloids. Taken together, this human multi-cellular platform will facilitate functional investigations of the cortico-striatal-thalamic-cortical circuit in the context of early human development and in disease conditions.

neuroscience↗

Infralimbic projections to the basal forebrain mediate extinction learning

Fear extinction learning and retrieval are critical for decreasing fear responses to a stimulus that no longer poses a threat. While it is known that the infralimbic region (IL) of the medial prefrontal cortex mediates retrieval of an extinction memory through projections to the basolateral amygdala (BLA), the contribution of the IL to extinction learning is not well-understood. Given the strong projection from the IL to the basal forebrain (BF), a center of attentional processing, we investigated whether this pathway participates in extinction, and compared it to the IL-BLA pathway. Using retrograde tracing, we first demonstrate that projections from the IL to the BF originate from superficial (L2/3) and deep cortical layers (L5), and that they are denser than IL projections to the BLA. Next, combining retrograde tracing with labeling of the immediate early gene cFos, we show increased activity of the L5 IL-BF pathway during extinction learning and increased activity of the L2/3 IL-BLA pathway during extinction retrieval. Our in vitro recordings demonstrate that neurons in the IL-BF pathway become more excitable towards the end of extinction learning, but less excitable during extinction retrieval. Finally, using optogenetics we show that inactivation of the IL-BF pathway impairs extinction learning, leaving retrieval intact. We propose that the IL acts as a switchboard operator during extinction, with increased L5 IL-BF communication during learning and increased L2/3 IL-BLA communication during retrieval. Anxiety and stress-related changes in IL physiology could affect one or multiple lines of communication, impairing different aspects of extinction. Significance StatementExtinction of conditioned fear is a widely used behavioral approach to diminish fear, with projections from infralimbic prefrontal cortex to the amygdala known for mediating extinction memory retrieval. However, less is known about infralimbic pathways involved in extinction learning. We use neuroanatomical tracing, behavior, slice recordings, and circuit manipulation to show that infralimbic output to the basal forebrain, an attention processing center, is denser than to the amygdala, and is active during extinction learning rather than retrieval. Neurons in the infralimbic-basal forebrain pathway become more excitable as extinction learning progresses, and then less excitable during extinction retrieval. Moreover, inhibiting this pathway impairs extinction learning. Our findings identify different lines of communication the infralimbic cortex uses for extinction learning and retrieval.

neuroscience↗

Axonal distribution of mitochondria maintains neuronal autophagy during aging via eIF2β

Neuronal aging and neurodegenerative diseases are accompanied by proteostasis collapse, while the cellular factors that trigger it have not been identified. Impaired mitochondrial transport in the axon is another feature of aging and neurodegenerative diseases. Using Drosophila, we found that genetic depletion of axonal mitochondria causes dysregulation of protein degradation. Axons with mitochondrial depletion showed abnormal protein accumulation and autophagic defects. Lowering neuronal ATP levels by blocking glycolysis did not reduce autophagy, suggesting that autophagic defects are associated with mitochondrial distribution. We found that eIF2{beta} was increased by the depletion of axonal mitochondria via proteome analysis. Phosphorylation of eIF2, another subunit of eIF2, was lowered, and global translation was suppressed. Neuronal overexpression of eIF2{beta} phenocopied the autophagic defects and neuronal dysfunctions, and lowering eIF2{beta} expression rescued those perturbations caused by depletion of axonal mitochondria. These results indicate the mitochondria-eIF2{beta} axis maintains proteostasis in the axon, of which disruption may underlie the onset and progression of age-related neurodegenerative diseases. HighlightsO_LILoss of axonal mitochondria impairs autophagy and accumulates proteins in the axon C_LIO_LILoss of axonal mitochondria increases eIF2{beta} and decreases p-eIF2 C_LIO_LINeuronal upregulation of eIF2{beta} induces autophagic defects and locomotor dysfunction C_LIO_LILowering eIF2{beta} rescues autophagic defects caused by loss of axonal mitochondria C_LI

cell biology↗

Kirigami electronics for long-term electrophysiological recording of human neural organoids and assembloids

Organoids and assembloids have emerged as a promising platform to model aspects of nervous system development. Longterm, minimally-invasive recordings in these multi-cellular systems are essential for developing disease models. Current technologies, such as patch-clamp, penetrating microelectrodes, planar electrode arrays and substrate-attached flexible electrodes, do not, however, allow chronic recording of organoids in suspension, which is necessary to preserve their architecture. Inspired by the art of kirigami, we developed flexible electronics that transition from a 2D pattern to a 3D basketlike configuration to accommodate the long-term culture of organoids in suspension. This platform, named kirigami electronics (KiriE), integrates with and enables chronic recording of cortical organoids while preserving morphology, cytoarchitecture, and cell composition. KiriE can be integrated with optogenetic and pharmacological stimulation and model disease. Moreover, KiriE can capture activity in cortico-striatal assembloids. Moving forward, KiriE could reveal disease phenotypes and activity patterns underlying the assembly of the nervous system.

neuroscience↗

Random walk and cell morphology dynamics in Naegleria gruberi

Amoeboid cell movement and migration are wide-spread across various cell types and species. Microscopy-based analysis of the model systems Dictyostelium and neutrophils over the years have uncovered generality in their overall cell movement pattern. Under no directional cues, the centroid movement can be quantitatively characterized by their persistence to move in a straight line and the frequency of re-orientation. Mathematically, the cells essentially behave as a persistent random walker with memory of two characteristic time-scale. Such quantitative characterization is important from a cellular-level ethology point of view as it has direct connotation to their exploratory and foraging strategies. Interestingly, outside the amoebozoa and metazoa, there are largely uncharacterized species in the excavate taxon Heterolobosea including amoeboflagellate Naegleria. While classical works have shown that these cells indeed show typical amoeboid locomotion on an attached surface, their quantitative features are so far unexplored. Here, we analyzed the cell movement of Naegleria gruberi by employing long-time phase contrast imaging to automatically track individual cells. We show that the cells move as a persistent random walker with two time-scales that are close to those known in Dictyostelium and neutrophils. Similarities were also found in the shape dynamics which is characterized by the appearance, splitting and annihilation of the curvature waves along the cell edge. Our analysis based on the Fourier descriptor and a neural network classifier point to importance of morphology features unique to Naegleria including complex protrusions and the transient bipolar dumbbell morphologies.

cell biology↗

Generating human neural diversity with a multiplexed morphogen screen in organoids

Morphogens choreograph the generation of remarkable cellular diversity in the developing nervous system. Differentiation of stem cells toward particular neural cell fates in vitro often relies upon combinatorial modulation of these signaling pathways. However, the lack of a systematic approach to understand morphogen-directed differentiation has precluded the generation of many neural cell populations, and knowledge of the general principles of regional specification remain in-complete. Here, we developed an arrayed screen of 14 morphogen modulators in human neural organoids cultured for over 70 days. Leveraging advances in multiplexed RNA sequencing technology and annotated single cell references of the human fetal brain we discovered that this screening approach generated considerable regional and cell type diversity across the neural axis. By deconvoluting morphogen-cell type relationships, we extracted design principles of brain region specification, including critical morphogen timing windows and combinatorics yielding an array of neurons with distinct neuro-transmitter identities. Tuning GABAergic neural subtype diversity unexpectedly led to the derivation of primate-specific interneurons. Taken together, this serves as a platform towards an in vitro morphogen atlas of human neural cell differentiation that will bring insights into human development, evolution, and disease.

neuroscience↗

CD4+ T-cell immunity of SARS-CoV-2 patients determine pneumonia development

Most humans infected with SARS-CoV-2 will recover without developing pneumonia. A few SARS-CoV-2 infected patients, however, develop pneumonia, and occasionally develop cytokine storms. In such cases, it is assumed that there is an inadequate immune response to eliminate viral infected cells and an excessive inappropriate immune response causing organ damage, but little is known about this mechanism. In this study, we used single cell RNA sequencing and mass cytometry to analyze peripheral blood T cells from patients hospitalized with proven COVID-19 infection in order to clarify the differences in host immune status among COVID-19 pneumonia cases, non-pneumonia cases, and healthy controls. The results showed that a specific CD4+ T cell cluster with chemokine receptor expression patterns, CXCR3+CCR4-CCR6+ (Th1/17), was less abundant in COVID-19 pneumonia patients. Interestingly, these CD4+ T-cell clusters were identical to those we have reported to correlate with antitumor immunity and predict programmed cell death (PD)-1 blockade treatment response in lung cancer. The Th1/17 cell percentages had biomarker performance in diagnosing pneumonia cases. In addition, CTLA-4 expression of type17 helper T cells (Th17) and regulatory T cells (Treg) was found to be significantly lower. This indicates that functional suppression of Th17 was less effective and Treg function was impaired in pneumonia cases. These results suggest that imbalance of CD4+ T-cell immunity generates excessive immunity that does not lead to viral eradication. This might be a potential therapeutic target mechanism to prevent severe viral infections. ImportanceIn this observational study, 49 consecutive patients with SARS-CoV-2 infection confirmed by PCR testing and admitted to Saitama Medical University Hospital and Saitama Medical University International Medical Centre between December 4, 2020 and January 17, 2022 were included. Of these 49 patients, 29 were diagnosed with COVID-19 pneumonia by computed tomography (CT) scan (Table 1). The unique CD4+ T-cell immunity with less abundant Th1/17 CD4+ T-cell cluster and low expression of CTLA-4 in Th17 and Treg was consistently found in SARS-CoV-2 pneumonia patients on admission and 1-week of admission. The imbalance of CD4+ T-cell immunity may contribute to develop pneumonia in SARS-CoV-2 virus infected patients by delaying viral clearance and resulting in an excessive immune response. O_TBL View this table: org.highwire.dtl.DTLVardef@1aac015org.highwire.dtl.DTLVardef@128c14dorg.highwire.dtl.DTLVardef@aacabaorg.highwire.dtl.DTLVardef@e39c8eorg.highwire.dtl.DTLVardef@13b439a_HPS_FORMAT_FIGEXP M_TBL O_FLOATNOTable 1C_FLOATNO O_TABLECAPTIONPatient demographics C_TABLECAPTION C_TBL

immunology↗

Human assembloids reveal the consequences of CACNA1G gene variants in the thalamocortical pathway

Abnormalities in crosstalk between the thalamus and the cerebral cortex are thought to lead to severe neuropsychiatric disorders, such as epilepsy and psychotic disorders. Pathogenic variants in the CACNA1G gene, which encodes the 1G subunit of the thalamus-enriched T-type voltage-gated calcium channel CaV3.1, are associated with absence seizures, intellectual disability, and schizophrenia, but the cellular and circuit level consequences of these genetic variants in humans remain unknown. Here, we developed an in vitro human assembloid model of the thalamocortical pathway to systematically dissect the contribution of genetic variants in T-type calcium channels. We discovered that a CACNA1G variant (M1531V) associated with seizures led to changes in T-type currents in human thalamic neurons, as well as correlated hyperactivity of thalamic and cortical neurons in thalamo-cortical assembloids. In contrast, CACNA1G loss, which has been associated with risk of schizophrenia, resulted in abnormal thalamocortical connectivity that was related to both increased spontaneous thalamic activity and aberrant thalamic axonal projections. Taken together, these results illustrate the utility of organoid and assembloid systems for interrogating human genetic disease risk variants at both cellular and circuit level.

neuroscience↗

OVGP1 is an oviductal fluid factor essential particularly for early embryonic development in golden hamsters

The mammalian oviductal lumen is a specialized chamber that provides an environment that strictly regulates fertilization an early embryogenesis, the regulatory mechanisms to gametes/zygote are still largely unknown. In this report, we studied the oviductal regulation of early embryonic development using Ovgp1 (a gene encoding an oviductal humoral factor, OVGP1)-knockout (KO) hamsters. The experimental results revealed the following: 1) Female Ovgp1-KO hamsters fail to produce any litters at all; 2) In the oviducts from KO animal, fertilized eggs are sometimes identified, but their morphology shows abnormal features; 3) The number of implantations in the KO females is evidently low; 4) Even if implantations occur, the embryos develop abnormally and eventually become embryonic lethal; and 5) Ovgp1-KO females transferred to wild-type females produce KO egg-derived litters, but the reverse experiment does not. These results suggest that OVGP1-mediated physiological events are crucial for early embryonic development in vivo. This animal model shows that the fate of the fertilized egg is not only genetically determined, but that the surrounding oviductal microenvironment plays a pivotal role in normal embryonic development. Summary statementDeficiency an oviductal humoral factor (OVGP1) caused female infertility in the golden hamsters. The presence or absence of OVGP1 has significant physiological effects on early embryonic development in vivo.

developmental biology↗

Coordination chemogenetics for activation of GPCR-type glutamate receptors in brain tissue

Direct activation of cell-surface receptors is highly desirable for elucidating the physiological roles of receptors. However, subtype-selective ligands are very limited because of the high homology among receptor subtypes. A potential approach for selective activation of a receptor subtype is chemogenetics, in which both point mutagenesis of the receptors and designed ligands are used. However, ligand-binding properties are affected in most current methods. Here, we developed a chemogenetic method for direct activation of metabotropic glutamate receptor 1 (mGlu1), which plays essential roles in cerebellar functions in the brain. Our screening identified a mGlu1 mutant, mGlu1(N264H), that was directly activated by palladium complexes. Notably, a palladium complex showing low cytotoxicity successfully activated mGlu1 in mGlu1(N264H) knock-in mice, revealing that activation of endogenous mGlu1 is sufficient to evoke the critical cellular mechanism of synaptic plasticity, a basis of motor learning in the cerebellum.

neuroscience↗

Bimodal fibrosis in a novel mouse model of bleomycin-induced usual interstitial pneumonia

Idiopathic pulmonary fibrosis (IPF) is pathologically classified by usual interstitial pneumonia (UIP). Conventional bleomycin models used to study pathogenic mechanisms of pulmonary fibrosis display transient inflammation and fibrosis so their relevance to UIP is limited. We developed a novel chronic induced-UIP (iUIP) model, inducing fibrosis in D1CCxD1BC transgenic mice by intra-tracheal instillation of bleomycin mixed with microbubbles followed by sonoporation (BMS). A bimodal fibrotic lung disease was observed over 14 weeks, with an acute phase similar to nonspecific interstitial pneumonia (NSIP), followed by partial remission and a chronic fibrotic phase with honeycombing similar to UIP. In this secondary phase, we observed poor vascularization despite elevated PDGFR{beta} expression. {gamma}2PF- and MMP7-positive epithelial cells, consistent with an invasive phenotype, were predominantly adjacent to fibrotic areas. Most invasive cells were Scgb1a1 and/or keratin 5 positive. This iUIP mouse model displays key features of IPF and has identified potential mechanisms contributing to the onset of NSIP and progression to UIP. The model will provide a useful tool for the assessment of therapeutic interventions to oppose acute and chronic fibrosis. Summary blurbA novel mouse model of induced-usual interstitial pneumonia shows bimodal fibrosis with honeycombing, similar to chronic lung disease seen with idiopathic pulmonary fibrosis.

pathology↗