Biology subjects

Niu, X.

Publications and source records attributed to Niu, X..

At least 73 records · Page 4Linked to original sources

bioRxiv2021

Amelioration of hemophilia B through CRISPR/Cas9 induced homology-independent targeted integration

Site-specific integration of exogenous gene through genome editing is a promising strategy for gene therapy. However, homology-directed repair (HDR) only occurring in proliferating cells is inefficient especially in vivo. To investigate the efficacy of Cas9-induced homology-independent targeted integration (HITI) strategy for gene therapy, a rat hemophilia B model was generated and employed. Through HITI, a DNA sequence encoding the last exon of rat Albumin (rAlb) gene fused with a high-specific-activity Factor IX variant (R338L) using T2A, was inserted into the last intron of rAlb via recombinant adeno-associated viral (rAAV). The knock-in efficiency reached up to 3.66% determined by ddPCR. The clotting time was reduced to normal level 4 weeks after treatment, and the circulating FIX level was gradually increased up to 52% of normal during 9 months even after partial hepatectomy, demonstrating the amelioration of hemophilia. Through PEM-seq, no significant off-targeting effect was detected. Moreover, this study provides a promising therapeutic approach for hereditary diseases.

bioengineering↗

bioRxiv2021

An allosteric ligand stabilizes distinct conformations in the M2 muscarinic acetylcholine receptor

Allosteric modulators provide therapeutic advantages over orthosteric drugs. A plethora of allosteric modulators have been identified for several GPCRs, particularly for muscarinic receptors (mAChRs)1,2. To study the molecular mechanisms governing allosteric modulation, we utilized a recently developed NMR system to investigate the conformational changes in the M2 muscarinic receptor (M2R) in response to the positive allosteric modulator (PAM) LY2119620. Our studies provide the first biophysical data showing that LY2119620 can substantially change the structure and dynamics of M2R in both the extracellular and G-protein coupling domains during the activation process. These NMR data suggest that LY2119620 may function by stabilizing distinct sets of conformations not observed in the presence of orthosteric agonists alone, which may account for the different signaling behaviors of the M2R when bound to LY2119620. Our studies provide new structural information for understanding the mechanism of GPCR allostery, and may facilitate the rational design of allosteric therapeutics targeting muscarinic receptors.

biophysics↗

bioRxiv2020

Multidimensional brain-age prediction reveals altered brain developmental trajectory in psychiatric disorders

Neuroimaging-based brain-age prediction has emerged as an important new approach for studying brain development. However, brain regions change in different ways and at different rates. Unitary brain-age indices used in previous studies represent developmental status averaged across the whole brain and therefore do not capture the divergent developmental trajectories of various brain structures. Importantly, this staggered developmental unfolding, determined by genetics and postnatal experience, is implicated in the progression of psychiatric and neurological disorders. Here we propose an analytic method for computing a multidimensional brain-age index (MBAI) that provides regional age predictions. Using a database of 556 subjects (ages 8-21) that includes psychiatric and neurological patients as well as healthy controls, we conducted robust regression and cluster analyses to identify clusters of imaging features with distinct developmental trajectories. We then built machine-learning models to obtain brain-age predictions from each of the identified clusters to form the MBAI. Our results show that the MBAI provides a flexible analysis of region-specific brain-age changes that are invisible to unidimensional brain-age prediction methods. Importantly, brain ages computed from region-specific feature clusters contain complementary information and demonstrate differential ability to classify disorder groups (e.g., specific phobia, depression, ADHD) from healthy controls. Compared to unidimensional brain-age indices, we show that the MBAI is sensitive to alterations in brain structures and captures distinct regional change patterns which may serve as biomarkers that may contribute to our understanding of healthy and pathological brain development and to the characterization, diagnosis, and, potentially, treatment of various disorders.

neuroscience↗

bioRxiv2020

Circular RNA profiling reveals abundant and diverse circRNAs of SARS-CoV-2, SARS-CoV and MERS-CoV origin

Circular RNAs (circRNAs) encoded by DNA genomes have been identified across host and pathogen species as parts of the transcriptome. Accumulating evidences indicate that circRNAs play critical roles in autoimmune diseases and viral pathogenesis. Here we report that RNA viruses of the Betacoronavirus genus of Coronaviridae, SARS-CoV-2, SARS-CoV and MERS-CoV, encode a novel type of circRNAs. Through de novo circRNA analyses of publicly available coronavirus-infection related deep RNA-Sequencing data, we identified 351, 224 and 2,764 circRNAs derived from SARS-CoV-2, SARS-CoV and MERS-CoV, respectively, and characterized two major back-splice events shared by these viruses. Coronavirus-derived circRNAs are more abundant and longer compared to host genome-derived circRNAs. Using a systematic strategy to amplify and identify back-splice junction sequences, we experimentally identified over 100 viral circRNAs from SARS-CoV-2 infected Vero E6 cells. This collection of circRNAs provided the first line of evidence for the abundance and diversity of coronavirus-derived circRNAs and suggested possible mechanisms driving circRNA biogenesis from RNA genomes. Our findings highlight circRNAs as an important component of the coronavirus transcriptome. SummaryWe report for the first time that abundant and diverse circRNAs are generated by SARS-CoV-2, SARS-CoV and MERS-CoV and represent a novel type of circRNAs that differ from circRNAs encoded by DNA genomes.

microbiology↗

bioRxiv2020

A spiking neural circuit model for learning multi-sensory integration

Neurons in visual and vestibular information integration areas of macaque brain such as medial superior temporal (MSTd) and ventral intraparietal (VIP) have been classified into congruent neurons and opposite neurons, which prefer congruent inputs and opposite inputs from the two sensory modalities, respectively. In this work, we propose a mechanistic spiking neural model that can account for the emergence of congruent and opposite neurons and their interactions in a neural circuit for multi-sensory integration. The spiking neural circuit model is adopted from an established model for the circuits of the primary visual cortex with little changes in parameters. The network can learn, based on the basic Hebbian learning principle, the correct topological organization and behaviors of the congruent and opposite neurons that have been proposed to play a role in multi-sensory integration. This work explore the constraints and the conditions that lead to the development of a proposed neural circuit for cue integration. It also demonstrates that such neural circuit might indeed be a canonical circuit shared by computations in many cortical areas.

neuroscience↗

bioRxiv2020

Sustained ErbB activation causes demyelination and hypomyelination by driving necroptosis of mature oligodendrocytes and apoptosis of oligodendrocyte precursor cells

Oligodendrocytes are vulnerable to genetic and environmental insults and its injury leads to demyelinating diseases. The roles of ErbB receptors in maintaining the CNS myelin integrity are largely unknown. Here we overactivate ErbB receptors that mediate signaling of either neuregulin or EGF family growth factors and found their synergistic activation caused deleterious outcomes in white matter. Sustained ErbB activation induced by the tetracycline-dependent mouse tool Plp-tTA resulted in demyelination, axonal degeneration, oligodendrocyte precursor cell (OPC) proliferation, astrogliosis, and microgliosis in white matter. Moreover, there was hypermyelination prior to these inflammatory pathological events. In contrast, sustained ErbB activation induced by another tetracycline-dependent mouse tool Sox10+/rtTA caused hypomyelination in the corpus callosum and optic nerve, which appeared to be a developmental deficit and did not associate with OPC regeneration, astrogliosis, or microgliosis. By tracing the differentiation states of cells expressing tTA/rtTA-dependent transgene or pulse-labeled reporter proteins in vitro and in vivo, we found that Plp-tTA targeted mainly mature oligodendrocytes (MOs), whereas Sox10+/rtTA targeted OPCs and newly-formed oligodendrocytes. The distinct phenotypes of mice with ErbB overactivation induced by Plp-tTA and Sox10+/rtTA consolidated their non-overlapping targeting preferences in the oligodendrocyte lineage, and enabled us to demonstrate that ErbB overactivation in MOs induced necroptosis that caused inflammatory demyelination, whereas in OPCs induced apoptosis that caused non-inflammatory hypomyelination. Early interference with aberrant ErbB activation ceased oligodendrocyte deaths and restored myelin development in both mice. This study suggests that aberrant ErbB activation is an upstream pathogenetic mechanism of demyelinating diseases, providing a potential therapeutic target. Significance statementPrimary oligodendropathy is one of the etiological mechanisms for multiple sclerosis, and oligodendrocyte necroptosis is a pathological hallmark in the disease. Moreover, the demyelinating disease is now a broad concept that embraces schizophrenia, in which white matter lesions are an emerging feature. ErbB overactivation has been implicated in schizophrenia by genetic analysis and postmortem studies. This study suggests the etiological implications of ErbB overactivation in myelin pathogenesis and elucidates the pathogenetic mechanisms.

neuroscience↗

bioRxiv2020

Interpreting the dynamic pathogenesis of Parkinson's disease by longitudinal blood transcriptome analysis

Achieving an improved understanding of the temporal sequence of factors involved in Parkinsons disease (PD) pathogenesis may accelerate drug discovery. In this study, we performed a longitudinal transcriptome analysis to identify associated genes underlying the pathogenesis of PD at three temporal phases. We firstly found that multiple initiator genes, which are related to processes of olfactory transduction and stem cell pluripotency, indicate PD risk to those subjects at the prodromal phase. And many facilitator genes involved in calcium signaling and stem cell pluripotency contribute to PD onset. We next identified 325 aggravator genes whose expression could lead to disease progression through damage to dopaminergic synapses and ferroptosis via an integrative analysis with DNA methylation. Last, we made a systematic comparison of gene expression patterns across PD development and accordingly provided candidate drugs at different phases in an attempt to prevent the neurodegeneration process.

bioinformatics↗

bioRxiv2020

Structural Perturbations of Exon Skipping Edits within the Dystrophin D20:24 Region

Exon skipping is a disease modifying therapy that operates at the RNA level. In this strategy, oligonucleotide analog drugs are used to specifically mask specific exons and prevent them from inclusion in the mature mRNA. Of course, this also results in loss of the corresponding region from the cognate protein, which is one possible therapeutic aim. Exon skipping can also be used to restore protein expression in cases where a genetic frameshift mutation has occurred, and this how it is applied to Duchenne muscular dystrophy, DMD. DMD most commonly arises as a result of large exonic deletions that juxtapose flanking exons of incompatible reading frame in the dystrophin gene, creating a frameshift and abolishing protein expression. Loss of dystrophin protein leads to the pathology of the disease, which is severe, causing death generally in the second or third decade of life. Here, the primary aim of exon skipping is the restoration of the reading frame by skipping an exon adjacent to the patients original defect. However, the therapeutically expressed protein is of course edited, and missing both the region of the underlying genetic defect, as well as the therapeutically skipped exon. While restoring some protein expression is good, how removing some region from the middle of a protein effects its structure and function is unclear. Complicating this in the case of DMD is the fact that the dystrophin gene is very large, containing 79 exons. Many different underlying deletions are known, and exon skipping can be applied in many ways. It has previously been shown that many exon-skip edits result in structural perturbations of varying degrees. What has been unclear is whether and how exon editing can be done to minimize these perturbations. In this study we examine a systematic and comprehensive panel of possible exon edits in a region of the dystrophin protein, and identify for the first time, exon edits that appear to maintain structural stability similar to wildtype protein. We also identify factors that appear to be correlated with the degree of structural perturbation, such as the number of cooperative protein domains, as well as how the underlying exon structure interacts with the protein domain structure.

biochemistry↗

bioRxiv2020

A longitudinal study of white matter functional network in mild traumatic brain injury

The mild traumatic brain injury (mTBI) results in traumatic axonal injury, which damages the long-distance white matter (WM) connections and thus disrupts the functional connectome of large-scale brain networks that support cognitive function. Patterns of WM structural damage following mTBI were well documented using diffusion tensor imaging, however, the functional organization of WM and its association with grey matter functional networks (GM-FNs) and cognitive assessments remains unknown. The present study adopted resting-state functional magnetic resonance imaging to explore WM functional properties in mTBI patients (113 acute patients, 56 chronic patients, 47 healthy controls (HCs)). Eleven large-scale WM functional networks (WM-FNs) were constructed by the k-means clustering algorithm which carried out in voxel-wise WM functional connectivity (FC). Compared to HCs, acute mTBI patients showed enhanced FC between inferior fronto-occipital fasciculus (IFOF) WM-FN and primary sensorimotor WM-FNs, and cortical primary sensorimotor GM-FNs. And FC between IFOF WM-FN and anterior cerebellar GM-FN was positively correlated with information processing speed. Moreover, all of these WM-FNs abnormalities were returned to the normal level at the chronic stage. Our findings suggest the compensatory mechanism of cognitive deficits in the acute stage and its involvement in facilitating recovery from cognitive deficits in the chronic stage. The convergent damage of the IFOF network highlighted its key role in our understanding of the pathophysiology mechanism of mTBI patients and thus might be regarded as a biomarker in the acute stage and a potential indicator of treatment effect.

neuroscience↗

bioRxiv2020

ErbB dysregulation impairs cognition via myelination-dependent and -independent oligodendropathy

White matter abnormalities are an emerging pathological feature of schizophrenia. However, their attributions to the disease remain largely elusive. ErbB receptors and their ligands, some of which are essential for peripheral myelination, confer susceptibility to schizophrenia. By synergistically manipulating ErbB receptor activities in a oligodendrocyte-stage-specific manner in mice after early development, we demonstrate the distinct effects of ErbB signaling on oligodendrocytes at various differentiation states. ErbB overactivation, in mature oligodendrocytes, induces necroptosis causing demyelination, whereas in oligodendrocyte precursor cells, induces apoptosis causing hypomyelination. In contrast, ErbB inhibition increases oligodendrocyte precursor cell proliferation but induces hypomyelination by suppressing the myelinating capabilities of newly-formed oligodendrocytes. Remarkably, ErbB inhibition in mature oligodendrocytes diminishes axonal conduction under energy stress and impairs working memory capacity independently of myelin pathology. This study reveals the etiological implications of oligodendrocyte vulnerability induced by ErbB dysregulation, and elucidates the pathogenetic mechanisms for variable structural and functional white matter abnormalities.

neuroscience↗

bioRxiv2020

AD-linked R47H-TREM2 mutation induces disease-enhancing proinflammatory microglial states in mice and humans

The hemizygous R47H variant of TREM2, a microglia-specific gene in the brain, increases risk for late-onset Alzheimers disease (AD). In this study, we identified a subpopulation of microglia with disease-enhancing proinflammatory signatures associated with the R47H mutation in human AD brains and tauopathy mouse brains. Using transcriptomic analysis at the single-nuclei level from AD patients with the R47H or the common variant (CV)-TREM2 with matched sex, pathology and APOE status, we found that the R47H mutation was associated with cell type- and sex-specific transcriptional changes in human AD brains, with microglia exhibiting the most robust alterations. Further characterization revealed that R47H-associated microglial subpopulations had enhanced inflammatory signatures including hyperactivation of Akt, one of the signaling pathways downstream of TREM2. In a newly-generated tauopathy knock-in mouse model expressing one allele of human TREM2 (hTREM2) with either the R47H mutation or CV, R47H induced and exacerbated tau-mediated spatial memory deficits in female mice. Single-cell transcriptomic analysis of microglia from these mice also revealed transcriptomic changes induced by R47H that had significant overlaps with R47H microglia in human AD brains, including robust increases in proinflammatory cytokines, activation of Syk-Akt-signaling, and elevation of a subset of disease-associated microglial signatures. Strikingly, pharmacological Akt inhibition largely reversed the enhanced inflammatory signatures induced by R47H in primary microglia treated with tau fibrils. By unraveling the disease-enhancing properties of the R47H mutation in mouse and human, our findings shed light on an immune-linked AD subtype and provide new directions for modulating microglial immune responses to treat AD.

neuroscience↗

bioRxiv2020

Structural basis for the inhibition of the papain-like protease of SARS-CoV-2 by small molecules

SARS-CoV-2 is the pathogen responsible for the COVID-19 pandemic. The SARS-CoV-2 papain-like cysteine protease has been implicated in virus maturation, dysregulation of host inflammation and antiviral immune responses. We showed that PLpro preferably cleaves the K48-ubiquitin linkage while also being capable of cleaving ISG15 modification. The multiple functions of PLpro render it a promising drug target. Therefore, we screened an FDA-approved drug library and also examined available inhibitors against PLpro. Inhibitor GRL0617 showed a promising IC50 of 2.1 M. The co-crystal structure of SARS-CoV-2 PLpro-C111S in complex with GRL0617 suggests that GRL0617 is a non-covalent inhibitor. NMR data indicate that GRL0617 blocks the binding of ISG15 to PLpro. The antiviral activity of GRL0617 reveal that PLpro is a promising drug target for therapeutically treating COVID-19. One Sentence SummaryCo-crystal structure of PLpro in complex with GRL0617 reveals the druggability of PLpro for SARS-CoV-2 treatment.

biochemistry↗

bioRxiv2020

Balanced JAK/STAT signaling is critical to maintain the functional and structural integrity of the Drosophila respiratory epithelium

Signaling mediated by the Janus kinase (JAK)/Signal Transducer and Activator of Transcription (STAT) pathway is critical for maintaining cellular and functional homeostasis in the lung. Thus, chronically activated JAK/STAT signaling is causally associated with lung diseases such as lung cancer, asthma, and chronic obstructive pulmonary disease. To elucidate the molecular processes that transform increased JAK/STAT signaling in airway epithelial cells into the known pathological states, we used a highly simplified model system, the fruit fly Drosophila melanogaster. Here, the JAK/STAT pathway is permanently active in almost all airway cells and responds to airborne stressors with increased activity. Silencing of this signaling pathway in epithelial cells resulted in apoptosis. Since the above-mentioned lung diseases are commonly associated with increased JAK/STAT signaling, we assessed this by its ectopic activation in the respiratory epithelium of Drosophila. This intervention triggered cell-autonomous structural changes in epithelial cells. These structural changes included phenotypes associated with asthma, namely, thickening of the epithelium, substantial narrowing of the air-conducting space, and impairment of the secretory epicuticular structure of the tracheae. Pharmacological manipulation of JAK/STAT signaling reversed this pathological phenotype. Transcriptomic analyses revealed that several biological processes were affected, which is consistent with the impairment of junction protein trafficking also observed in this study. These results indicate that balanced JAK/STAT signaling is essential for the functionality of the respiratory epithelium and, by extension, the entire organ. In contrast, chronic overactivation of this signaling leads to massive structural changes that are closely associated with pathologies typical of chronic inflammatory lung diseases. HighlightsO_LIJAK/STAT signaling is active in the entire Drosophila respiratory system in all developmental stages. C_LIO_LIThe signaling pathway is indispensable for the survival of the tracheal cell. C_LIO_LIOveractivation of the signaling has significant effects on tracheal development and also displays a human disease-associated phenotype in Drosophila trachea. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/160929v2_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@1f82913org.highwire.dtl.DTLVardef@150a79corg.highwire.dtl.DTLVardef@2c1130org.highwire.dtl.DTLVardef@11c7cf8_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2020

Molecular mechanisms underlying the extreme mechanical anisotropy of the flaviviral exoribonuclease-resistant RNAs (xrRNAs)

Mechanical anisotropy is an essential property for many biomolecules to assume their structures, functions and applications, however, the mechanisms for their direction-dependent mechanical responses remain elusive. Herein, by using single-molecule nanopore sensing technique, we explore the mechanisms of directional mechanical stability of the xrRNA1 RNA from ZIKA virus (ZIKV), which forms a complex ring-like architecture. We reveal extreme mechanical anisotropy in ZIKV xrRNA1 which highly depends on Mg2+ and the key tertiary interactions. The absence of Mg2+ and disruption of the key tertiary interactions strongly affect the structural integrity and attenuate mechanical anisotropy. The significance of ring structure in RNA mechanical anisotropy is further supported by steered molecular dynamics simulations on ZIKV xrRNA1 and another two RNAs with ring structures, the HCV IRES and THF riboswitch. We anticipate the ring structures can be used as key elements to build RNA-based nanostructures with controllable mechanical anisotropy for biomaterial and biomedical applications.

biophysics↗

bioRxiv2020

Transcranial Focused Ultrasound Neuromodulation of Voluntary Movement-related Cortical Activity in Humans

Transcranial focused ultrasound (tFUS) is an emerging non-invasive brain stimulation tool for safely and reversibly modulating brain circuits. The effectiveness of tFUS on human brain has been demonstrated, but how tFUS influences the human voluntary motor processing in the brain remains unclear. We apply low-intensity tFUS to modulate the movement-related cortical potential (MRCP) originating from human subjects practicing a voluntary foot tapping task. 64-channel electroencephalograph (EEG) is recorded concurrently and further used to reconstruct the brain source activity specifically at the primary leg motor cortical area using the electrophysiological source imaging (ESI). The ESI illustrates the ultrasound modulated MRCP source dynamics with high spatiotemporal resolutions. The MRCP source is imaged and its source profile is further evaluated for assessing the tFUS neuromodulatory effects on the voluntary MRCP. Moreover, the effect of ultrasound pulse repetition frequency (UPRF) is further assessed in modulating the MRCP. ESI results show that tFUS significantly increases the MRCP source profile amplitude (MSPA) comparing to a sham ultrasound condition, and further, a high UPRF enhances the MSPA more than a low UPRF. This work provides the first evidence of tFUS enhancing the human voluntary movement-related cortical activity through excitatory modulation.

neuroscience↗

bioRxiv2019

Emergence of opposite neurons in a decentralized firing-rate model of multisensory integration

Multisensory integration areas such as dorsal medial superior temporal (MSTd) and ventral intraparietal (VIP) areas in macaques combine visual and vestibular cues to produce better estimates of self-motion. Congruent and opposite neurons, two types of neurons found in these areas, prefer congruent inputs and opposite inputs from the two modalities, respectively. A recently proposed computational model of congruent and opposite neurons reproduces their tuning properties and shows that congruent neurons optimally integrate information while opposite neurons compute disparity information. However, the connections in the network are fixed rather than learned, and in fact the connections of opposite neurons, as we will show, cannot arise from Hebbian learning rules. We therefore propose a new model of multisensory integration in which congruent neurons and opposite neurons emerge through Hebbian and anti-Hebbian learning rules, and show that these neurons exhibit experimentally observed tuning properties.

neuroscience↗

bioRxiv2019

Metabolic remodeling by TIGAR overexpression is a therapeutic target in esophageal squamous-cell carcinoma

Whole-genome sequencing has identified many amplified genes in esophageal squamous-cell carcinoma (ESCC); however, their roles and the clinical relevance have yet elucidated. Here we show TP53-induced glycolysis and apoptosis regulator (TIGAR) is a major player in ESCC progression and chemoresistance. TIGAR reprograms glucose metabolism from glycolysis to the glutamine pathway through AMP-activated kinase, and its overexpression is correlated with poor disease outcomes. Tigar knockout mice have reduced ESCC growth and tumor burden. Treatment of TIGAR-overexpressed ESCC cell xenografts and patient-derived tumor xenografts in mice with combination of glutaminase inhibitor and chemotherapeutic agents achieves significant more efficacy than chemotherapy alone. These findings shed light on an important role of TIGAR in ESCC and provide evidence for targeted treatment of TIGAR-overexpressed ESCC.\n\nSignificanceEffective and target therapies are required for ESCC, one of the most common types of digestive OR cancer. Little has been known about the biology of ESCC progression or potential molecular targets OR for treatment. Whole-genome sequencing and RNA sequencing studies in ESCC have identified OR many recurrent copy number gain genes; however, the roles and druggable relevance of these OR genes remains poorly understood. Herein we demonstrate that TIGAR overexpression leads to OR metabolic remodeling, promoting ESCC progression and resistance to chemotherapeutic agents. OR Inhibiting the glutamine pathway significantly represses TIGAR-overexpressing ESCC growth and OR enhances tumor cell sensitization to cytotoxic agents. These findings might provide the rationale OR for clinical trials testing glutamine pathway inhibitors in combination with chemotherapy in OR TIGAR-expressing ESCC.

cancer biology↗

bioRxiv2019

Map3k2-Regulated Intestinal Stromal Cells (MRISC) Define a Distinct Sub-cryptic Stem Cell Niche for Damage Induced Wnt Agonist R-spondin1 Production

Intestinal stem cell propagation and differentiation are essential for rapid repair of tissue damage in the gut. While intestinal stromal cells were recently identified as key mediators of this process, the cellular and molecular mechanisms by which this diverse population induces tissue repair remains poorly understood. Here we show that Map3k2 has a colon stromal cell specific function critically required for maintenance of Lgr5+ intestinal stem cells and protection against acute intestinal damage. This Map3k2-specific function is mediated by enhancing Wnt agonist R-spondin1 production. We further reveal a unique novel cell population, named Map3k2-regulated intestinal stromal cells (MRISC), as the primary cellular source of R-spondin1 following intestinal injury. Together, our data identify a novel intestinal stem cell niche organized by MRISC, which specifically dependent on the Map3k2-signaling pathway to augment the production of Wnt agonist R-spondin1 and promote regeneration of the acutely damaged intestine.\n\nHighlightsO_LIMap3k2 protects mice from DSS-induced colitis by promoting intestinal stem cell regeneration.\nC_LIO_LIMap3k2-MAPK pathway cross-talks with Wnt signaling pathway via upregulation of R-spondin1.\nC_LIO_LIMap3k2-Regulated Intestinal Stromal Cells (MRISC) marked by co-expression of CD90, CD34 and CD81 defines a novel colonic stem cell niche.\nC_LI

cell biology↗