Biology subjects

Jing, M.

Publications and source records attributed to Jing, M..

At least 19 recordsLinked to original sources

bioRxiv2026

Astrocyte-to-microglia purinergic signaling mediates synaptic shielding and promotes neuronal activity

How glial cells sense and regulate neuronal hypoactivity remains poorly understood. Using in vivo imaging in anesthetized, sleeping, and behaving mice, we identified a glial purinergic signaling mechanism that converts neuronal hypoactivity into local circuit regulation. Cortical hypoactivity increased spatially confined ATP release through astrocytic pannexin-1 hemichannels, which were structurally enriched near perisomatic parvalbumin-positive boutons. Local ATP release directed microglial process movement and stabilized bulbous endings through microglial P2Y12 signaling, accompanied by localized Ca{superscript 2} activity in microglial processes. Disruption of astrocytic pannexin-1 or microglial P2Y12 impaired bulbous-ending stabilization and abolished rebound increases in neuronal activity during emergence from anesthesia. Similar ATP release and bulbous-ending formation were observed during chemogenetic neuronal silencing or natural sleep in freely behaving mice. These findings identify astrocyte-to-microglia purinergic signaling as a mechanism that converts neuronal hypoactivity into synapse-selective microglial regulation of circuit activity.

neuroscience↗

bioRxiv2025

Efficient Identification of Short Tandem Repeats via Context-Aware Motif Discovery and Ultra-Fast Sequence Alignment

Tandem repeats (TRs) are highly polymorphic genomic elements, associated with diverse molecular traits and implicated in numerous human diseases. However, large-scale analysis of TRs has been limited by computational challenges, including motif recognition, detection in complex regions, and excessive computational cost. Here we present FastSTR, a computationally efficient tool for precise detection and characterization of TRs. FastSTR integrates a context-aware N-gram motif model with a segmented global alignment algorithm to enable accurate motif identification and boundary definition, even for repeat units up to 8 bp. Across 13 species, FastSTR achieved >90% recall and 99% precision, running several times faster than existing methods white outperforming them in both sensitivity and accuracy. Applied to the human genome, FastSTR uncovered previously unannotated HSATII elements, resolved population-specific TR demonstrate, and identified recurrent STR alterations in lung cancer. These results demonstrate FastSTR as a versatile framework for TR annotation and discovery, advancing studies of genome evolution, genetic diversity, and disease.

bioinformatics↗

bioRxiv2024

Enhanced purinergic signaling in the paraventricular hypothalamus induces hyperphagic obesity and insulin resistance

Body energy homeostasis is tightly regulated by hypothalamic neural circuits. However, their remodeling upon metabolic challenges remains incompletely characterized, thus complicating the development of safe medications against the surge of metabolic diseases. Oxytocin (OXT) neurons in the paraventricular nucleus of the hypothalamus (PVH) are one of the key effectors regulating energy balance. In this work, we report that high-fat diet (HFD) feeding in mice evokes spatiotemporally selective ATP release from astrocytes (Inflares) in the PVH, accompanied by the expression of hematopoietic lineage-specific ADP/ATP receptor P2Y12 on local OXT (PVHOXT) neurons. Strikingly, increased purinergic signaling leads to impaired responsiveness of PVHOXT neurons accompanied by hyperphagic obesity and insulin resistance in mice. Conversely, loss of P2Y12 in PVHOXT neurons attenuates metabolic phenotypes, illustrating that such remodeling is both necessary and sufficient to induce metabolic phenotypes. Inflares were also induced by hyperglycemia, while emergence of P2Y12 on OXT neurons of patients with diabetes mellitus suggests an evolutionary conserved purinergic response to various metabolic challenges and its potential as a drug target. Accordingly, nasal administration of clinically approved doses of P2Y12 inhibitors counteracts obesity in mice and non-human primates, paving the way for application of these compounds in patients with metabolic disorders.

neuroscience↗

bioRxiv2024

An axonal brake on striatal dopamine output by cholinergic interneurons

Depolarisation of distal axons is necessary for neurons to translate somatic action potentials into neurotransmitter release. Studies have shown that striatal cholinergic interneurons (ChIs) can directly drive ectopic action potentials in dopamine (DA) axons and trigger DA release. However, here we show that this action occurs within a broader context of axonal signal integration whereby activation of ChIs and depolarisation of DA axons by nicotinic receptors (nAChRs) limits the subsequent depolarisation and release of DA in response to ensuing activity. We demonstrate that activation of ChIs and nAChRs in ex vivo mouse striatum, even when it does not trigger DA release that is detectable by fast-scan cyclic voltammetry, limits DA release for [~]100 ms by depressing subsequent axonal depolarisation and calcium summation. This axonal brake on DA release is stronger in dorsal than ventral striatum, and is unrelated to DA depletion. In vivo, antagonism of nAChRs in dorsal striatum elevated extracellular DA levels and promoted conditioned place-preference, underscoring its physiological relevance. Our findings reveal that under physiological conditions in vivo, ChIs acting via nAChRs dynamically attenuate DA output driven by DA neuron activity, leading to a predominantly inverse relationship between ACh and DA signalling that varies continuously with ChI activity.

neuroscience↗

bioRxiv2023

The origin, divergence and inter-subspecies hybridization of house mice (Mus musculus)

House mice (Mus musculus) are the ancestors of laboratory mouse strains and an excellent model for evolutionary biology. The origin, divergence and inter-subspecies hybridization of the three main subspecies (Mus musculus domesticus, M. m. musculus, M. m. castaneus) were not well-resolved. Population genomic analyses with 349 samples from Eurasia confirmed the Himalayas-India-Pakistan junctional region as the origin centre. The divergence of M. m. domesticus, M. m. musculus and M. m. castaneus occurred [~]333.6, 308.3 and 134.4 thousand years ago, respectively, which located in different interglacial stages in Pleistocene. Hybridization among M. m. domesticus, M. m. musculus, and M. m. castaneus after secondary contact during spread and gene flow between the ancestral population and different subspecies produced distinct genomic mixtures in populations from different regions of Eurasia. Long-distance introgression from M. m. musculus into M. m. castaneus and from M. m. castaneus into M. m. musculus happened in southern China and northern China, respectively. And extensive genomic introgression occurred on both autosomes and the X chromosomes. Genomic introgression in hybrids from East Asia and Europe revealed that the level of genomic differentiation, recombination rate and benefits for the survival and reproduction of hybrids determined the introgression capability of distinct genomic regions in inter-subspecies hybridization of house mice. Unidirectional introgression of the Y chromosome made all wild mice in East Asia hold the musculus-type Y chromosome. Our study provided comprehensive insights into the origin, divergence and inter-subspecies genomic introgression of house mice.

evolutionary biology↗

bioRxiv2023

DNA damage primes hematopoietic stem cells for direct megakaryopoiesis

Hematopoietic stem cells (HSCs) reside in the bone marrow (BM), can self-renew, and generate all cells of the hematopoietic system.1 Most hematopoietic lineages arise through successive, increasingly lineage-committed progenitors. In contrast, megakaryocytes (MKs), hyperploid cells that generate platelets essential to hemostasis, can derive rapidly and directly from HSCs.2 The underlying mechanism is unknown however. Here we show that DNA damage and subsequent arrest in the G2 phase of the cell cycle rapidly induce MK commitment specifically in HSCs, but not in progenitors, through an initially predominantly post-transcriptional mechanism. Cycling HSCs show extensive replication-induced DNA damage associated with uracil misincorporation in vivo and in vitro. Consistent with this notion, thymidine attenuated DNA damage, rescued HSC maintenance and reduced the generation of CD41+ MK-committed HSCs in vitro. Similarly, overexpression of the dUTP-scavenging enzyme, dUTPase, enhanced in vitro maintenance of HSCs. We conclude that a DNA damage response drives direct megakaryopoiesis and that replication stress-induced direct megakaryopoiesis, at least in part caused by uracil misincorporation, is a barrier to HSC maintenance in vitro. DNA damage-induced direct megakaryopoiesis may allow rapid generation of a lineage essential to immediate organismal survival, while simultaneously removing damaged HSCs and potentially avoiding malignant transformation of self-renewing stem cells.

cell biology↗

bioRxiv2022

A pair of NLRs coordinately modulates NRC3-mediated ETI responses to facilitate age-dependent immunity

Two NLRs (Nucleotide-binding and Leucine-rich repeat Receptors) adjacent to each other on a locus, termed as paired NLRs, may act separately for effector recognition and subsequent signaling activation to mediate effector-triggered immunity (ETI) in many plants. However, it is largely unknown about their distribution and functions in Solanaceae species, in which NLR-Hs (Helpers NLR REQUIRED FOR CELL DEATHs) have been extensively studied. Here, we identified paired NLRs in Solanaceae species and found they harbor paired NLRs ranging from 6 to 100, which are significantly negatively correlated with the numbers of NLR-Hs. N. benthamiana has six paired NLRs, among which silencing of NRCX exhibits phenotypes of dwarfism and accelerated senescence. Importantly, NRCX-silencing phenotypes could be restored by simultaneously silencing its head-to-head NLR pair, thus we named it as NRCY. NRCX/Y pair is specific in Solanaceae species. NRCY contains non-canonical walker B and MHD motifs, but could not induce autoactive cell death in N. benthamiana. Instead of that, silencing NRCY impaired cell death triggered by Sw5b-Nsm and NRC3D480V, indicating NRCY is also an NLR modulator like NRCX. Furthermore, NRCX suppression of Sw5b-Nsm and NRC3-mediated cell death is dependent on NRCY. Remarkably, we found that NRCX and NRCY expressions were induced during plant senescence, while NRCY was induced more than NRCX. Accordingly, the plant resistance was stronger during maturation, indicated NRCX/Y might be involved in age-dependent resistance. Our study reveals one of the paired NLRs coordinately regulates ETI to facilitate age-dependent immunity.

plant biology↗

bioRxiv2022

GESIAP: A Versatile Genetically Encoded Sensor-based Image Analysis Program

Intercellular communication mediated by a large number of neuromodulators diversifies physiological actions, yet neuromodulation remains poorly understood despite the recent upsurge of genetically encoded transmitter sensors. Here, we report the development of a versatile genetically encoded sensor-based image analysis program (GESIAP) that utilizes MATLAB-based algorithms to achieve high-throughput, high-resolution processing of sensor-based functional imaging data. GESIAP enables delineation of fundamental properties (e.g., transmitter spatial diffusion extent, quantal size, quantal content, release probability, pool size, and refilling rate at single release sites) of transmission mediated by various transmitters (i.e., monoamines, acetylcholine, neuropeptides, and glutamate) at various cell types (i.e., neurons, astrocytes, and other non-neuronal cells) of various animal species (i.e., mouse, rat, and human). Our analysis appraises a dozen of newly developed transmitter sensors, validates a conserved model of restricted non-volume neuromodulatory synaptic transmission, and accentuates a broad spectrum of presynaptic release properties that variegate neuromodulation.

neuroscience↗

bioRxiv2022

Spatiotemporally selective ATP events from astrocytes encode injury information and guide sustained microglial response

Brain injuries, either directly result from external assaults or are accompanied with diseases, initiate a cascade of intrinsic responses for damage management, with resident microglia as one of the key responders in the early phase of reaction. Changes in microglia including their motility and activities can be tuned according to injury intensity and position, indicating such injury information is precisely encoded and actively presented. Also, microglia in a broad area can perform sustained migration towards a transient and local injury, suggesting a signal amplification process may exist that bridge differences between injury and microglial migration in time and space. Currently, the molecular identity and underlying mechanism for injury encoding, amplification and presentation have not been fully elucidated yet, although candidate molecules like ATP are linked with both injury and microglial response. Based upon our recent technique advancement in engineering novel genetically-encoded ATP sensors, we here identified and characterized that in the cortex of awake mice in vivo, a new type of spatiotemporally selective ATP events, referred to as Inflares, was selectively evoked after brain injuries, which were actively and repeatedly generated from astrocytes in a Ca2+-dependent manner through the opening of pannexin 1 channel. Functionally, Inflares amplified local injury over time and space with their persistence and widespread distribution, and provided continuous directionality that was necessary for guiding microglial migration. Excessive Inflares in pathological injuries drove microglial dysfunction and caused secondary damage, whereas blocking Inflares successfully reversed pathological changes and benefited the outcome of ischemic stroke. Together, we identified the internal mechanism that encoded and presented injury information, and provided rational target for treating injury-related diseases.

neuroscience↗

bioRxiv2022

Local 5-HT signal bi-directionally regulates the coincidence time window of associative learning

Temporal coincidence between the conditioned stimulus (CS) and unconditioned stimulus (US) is essential for associative learning across species. Despite its ubiquitous presence, the mechanism that may regulate this time window duration remains unclear yet. Using olfactory associative learning in Drosophila as a model, we find that suppressing or promoting serotonin (5-HT) signal could respectively shorten or prolong the coincidence time window of odor-shock associative learning and synaptic plasticity in mushroom body (MB) Kenyon cells (KCs). Capitalizing on GPCR-activation based (GRAB) sensors for 5-HT and acetylcholine (ACh), we characterized the in vivo 5-HT dynamics in MB lobes during odor and shock stimulations and further dissected this microcircuit. Interestingly, local KC-released ACh activates nicotinic receptors on the dorsal paired medial (DPM) neuron, and in turn the DPM neuron releases 5-HT to inhibit the ACh signal via the 5-HT1a receptor. Finally, we demonstrated that the DPM-mediated serotonergic feedback circuit is sufficient and necessary to regulate the coincidence time window. This work provides a model for studying the temporal contingency of environmental events and their causal relationship.

neuroscience↗

bioRxiv2021

Directed motor actions and choice signalling drive cortical acetylcholine dynamics.

Numerous cognitive functions including attention and learning are influenced by the dynamic patterns of acetylcholine release across the brain. How acetylcholine mediates these functions in cortex remains unclear, as the relationship between cortical acetylcholine and behavioral events has not been precisely measured across task learning. To dissect this relationship, we quantified motor behavior and sub-second acetylcholine dynamics in primary somatosensory and auditory cortex during rewarded sensory detection and discrimination tasks. We found that acetylcholine dynamics were directly attributable to goal-directed actions (whisker motion and licking), rather than delivery of sensory cues or rewards. As task performance improved across training, acetylcholine release associated with the first lick in a trial was strongly and specifically potentiated. These results show that acetylcholine dynamics in sensory cortex are driven by directed motor actions to gather information and act upon it.

neuroscience↗

bioRxiv2021

A novel Phytophthora sojae effector PsFYVE1 modulates transcription and alternative splicing of immunity related genes by targeting host RZ-1A protein

Oomycete pathogens secrete many effectors to manipulate plant immunity and promote infection. However, relatively few effector types have been well characterized. In this study, members of a FYVE domain-containing protein family that is highly expanded in oomycetes were systematically identified, and one secreted protein, PsFYVE1, was selected for further study. PsFYVE1 enhanced Phytophthora infection in Nicotiana benthamiana and was necessary for P. sojae virulence. The FYVE domain of PsFYVE1 had PI3P-binding activity that depended on four conservative amino acid residues. Furthermore, PsFYVE1 targeted RNA-binding proteins RZ-1A/1B/1C in N. benthamiana and soybean, and silencing of NbRZ-1A/1B/1C genes attenuates plant immunity. NbRZ-1A was associated with spliceosome that included three important components, NbGRP7, NbGRP8, and NbU1-70K. Notably, PsFYVE1 could disrupt NbRZ-1A-NbGRP7 interaction. RNA-seq and subsequent experimental analysis demonstrated that PsFYVE1 and NbRZ-1A not only co-regulated transcription of NbHCT, NbEIN2, and NbSUS4 genes but also modulated pre-mRNA alternative splicing (AS) of the NbNSL1 gene, which participated in plant immunity. Collectively, these findings indicate that the FYVE domain-containing protein family includes potential new effector types and also highlight that plant pathogen effectors can regulate plant immunity related genes at both transcription and AS levels to promote disease. Author summaryMany plant pathogenic oomycetes secrete effector proteins into plants to facilitate infection. Discovering potential repertoire of novel effectors and corresponding molecular mechanisms are major themes in the study of oomycete-plant interactions. Here, we characterized a FYVE domain-containing protein (PsFYVE1) in P. sojae. PsFYVE1 carries a functional secretory signal peptide and is a virulence-essential effector for P. sojae infection. We demonstrated that PsFYVE1 interacted with a class of plant RNA-binding proteins, including soybean GmRZ-1A/1B/1C and N. benthamiana NbRZ-1A/1B/1C. Silencing of NbRZ-1A/1B/1C proteins increased Phytophthora infection and suppressed plant defense. Furthermore, NbRZ-1A interacted with the spliceosome components, and PsFYVE1 disrupted association between NbRZ-1A and spliceosome component NbGRP7. We examined the global transcription and alternative splicing (AS) changes regulated by PsFYVE1 and NbRZ-1A, which indicated that PsFYVE1 and NbRZ-1A co-regulated transcription and pre-mRNA AS of immunity-related genes. Thus, this study identifies a novel virulence-related effector from P. sojae and a class of positive regulators of plant immunity, and reveals a detailed mechanism of effector-medicated transcription and AS regulation during pathogen-plant interactions.

pathology↗

bioRxiv2021

Associative learning drives longitudinally-graded presynaptic plasticity of neurotransmitter release along axonal compartments

Anatomical and physiological compartmentalization of neurons is a mechanism to increase the computational capacity of a circuit, and a major question is what role axonal compartmentalization plays. Axonal compartmentalization may enable localized, presynaptic plasticity to alter neuronal output in a flexible, experience-dependent manner. Here we show that olfactory learning generates compartmentalized, bidirectional plasticity of acetylcholine release that varies across the longitudinal compartments of Drosophila mushroom body (MB) axons. The directionality of the learning-induced plasticity depends on the valence of the learning event (aversive vs. appetitive), varies linearly across proximal to distal compartments following appetitive conditioning, and correlates with learning-induced changes in downstream mushroom body output neurons (MBONs) that modulate behavioral action selection. Potentiation of acetylcholine release was dependent on the CaV2.1 calcium channel subunit cacophony. In addition, contrast between the positive conditioned stimulus and other odors required the inositol triphosphate receptor (IP3R), which was required to maintain responsivity to odors in untrained conditions. Downstream from the mushroom body, a set of MBONs that receive their input from the {gamma}3 MB compartment were required for normal appetitive learning, suggesting that they represent a key node through which discriminative effects influence appetitive memory and decision-making. These data demonstrate that learning drives valence-correlated, compartmentalized, bidirectional potentiation and depression of synaptic neurotransmitter release, which rely on distinct mechanisms and are distributed across axonal compartments in a learning circuit.

neuroscience↗

bioRxiv2021

A functional topography within the cholinergic basal forebrain for processing sensory cues associated with reward and punishment

Basal forebrain cholinergic neurons (BFCNs) project throughout the cortex to regulate arousal, stimulus salience, plasticity, and learning. Although often treated as a monolithic structure, the basal forebrain features distinct connectivity along its anteroposterior axis that could impart regional differences in BFCN processing. Here, we performed simultaneous bulk calcium imaging from anterior and posterior BFCNs over a one-month period of variable reinforcement learning in mice. BFCNs in both regions showed equivalently weak responses to unconditioned visual stimuli and anticipated rewards. Anterior BFCNs in the horizontal limb of the diagonal band were more responsive to reward omission, more accurately classified behavioral outcomes, and more closely tracked fluctuations in pupil-indexed global brain state. Posterior BFCNs in globus pallidus and substantia innominata were more responsive to unconditioned auditory stimuli, orofacial movements, aversive reinforcement, and showed robust associative plasticity for punishment-predicting cues. These results identify a functional topography that diversifies cholinergic modulatory signals broadcast to downstream brain regions.

neuroscience↗

bioRxiv2021

An ultrasensitive GRAB sensor for detecting extracellular ATP in vitro and in vivo

The purinergic transmitter ATP (adenosine 5-triphosphate) plays an essential role in both the central and peripheral nervous systems, and the ability to directly measure extracellular ATP in real time will increase our understanding of its physiological functions. We developed an ultrasensitive GPCR Activation-Based ATP sensor called GRABATP1.0, with a robust fluorescence response to extracellular ATP when expressed in several cell types. This sensor has sub-second kinetics, ATP affinity in the range of tens of nanomolar, and can be used to localize ATP release with subcellular resolution. Using this sensor, we monitored ATP release under a variety of in vitro and in vivo conditions, including primary hippocampal neurons, a zebrafish model of injury-induced ATP release, and LPS-induced ATP-release events in individual astrocytes in the mouse cortex measured using in vivo two-photon imaging. Thus, the GRABATP1.0 sensor is a sensitive, versatile tool for monitoring ATP release and dynamics under both physiological and pathophysiological conditions.

neuroscience↗

bioRxiv2020

Dual color mesoscopic imaging reveals spatiotemporally heterogeneous coordination of cholinergic and neocortical activity.

Variation in an animals behavioral state is linked to fluctuations in brain activity and cognitive ability. In the neocortex, state-dependent control of circuit dynamics may reflect neuromodulatory influences including acetylcholine (ACh). While early literature suggested ACh exerts broad, homogeneous control over cortical function, recent evidence indicates potential anatomical and functional segregation of cholinergic signaling. Additionally, it is unclear whether states as defined by different behavioral markers reflect heterogeneous cholinergic and cortical network activity. We performed simultaneous, dual-color mesoscopic imaging of both ACh and calcium across the neocortex of awake mice to investigate their relationships with behavioral variables. We find that increasing arousal, categorized by different motor behaviors, is associated with spatiotemporally dynamic patterns of cholinergic release and enhanced large-scale network correlations. Overall, our findings demonstrate that ACh provides a highly dynamic and spatially heterogeneous signal that links fluctuations in behavior to functional reorganization of cortical networks.

neuroscience↗

bioRxiv2020

YTHDF1 drives intestinal immune response against bacterial infection

Invasion of pathogenic bacteria is a serious threat to intestinal health. Recent emerging evidence has demonstrated that N6-methyladenosine (m6A) is closely associated with innate immunity; however, the underlying mechanism remains unclear. Herein, we aim to explore the function and mechanism of m6A modification in the regulation of innate immune responses against bacterial pathogens in the intestine. Ribo-seq and m6A-seq data have demonstrated that YTHDF1, an m6A reader, directs the translation of tumor necrosis factor receptor-associated factor 6 (TRAF6) mRNA to regulate immune responses via modulation of m6A methylation near stop codon. Furthermore, we have identified a unique mechanism that the interaction between YTHDF1 and the host factor DDX60 are critical in regulating intestinal immune response against bacterial infection by recognizing TRAF6 target transcripts. Additionally, our results provide novel insights as to why YTHDF1 could recognize its unique targets using the same domain as other YTHDF proteins. This work identifies YTHDF1 as a key driver of intestinal immune responses and provides an avenue for development of novel strategies to modulate intestinal immune response against bacterial infection.

immunology↗

bioRxiv2020

A GRAB sensor reveals activity-dependent non-vesicular somatodendritic adenosine release

The purinergic signaling molecule adenosine (Ado) modulates many physiological and pathological brain functions,but its spatiotemporal release dynamics in the brain remains largely unknown. We developed a genetically encoded GPCR-Activation-Based Ado sensor (GRABAdo) in which Ado-induced changes in the human A2A receptor are reflected by fluorescence increases. This GRABAdo revealed that neuronal activity-induced extracellular Ado elevation was due to direct Ado release from somatodendritic regions of the neuron, requiring calcium influx through L-type calcium channels, rather than the degradation of extracellular ATP. The Ado release was slow ([~]30 s) and depended on equilibrative nucleoside transporters (ENTs) rather than conventional vesicular release mechanisms. Thus, GRABAdo reveals an activity-dependent slow Ado release from somatodendritic region of the neuron, potentially serving modulating functions as a retrograde signal.

neuroscience↗