Biology subjects

Wang, M.

Publications and source records attributed to Wang, M..

At least 379 records · Page 21Linked to original sources

bioRxiv2024

SHP-1 interacts with NFκB1 to inhibit its phosphorylation and nuclear translocation to suppress excessive bacterial inflammation

The protein tyrosine phosphatase SHP-1 is a key negative regulator in cancer by dephosphorylating multiple target molecules. Specially in the NF{kappa}B signaling, where NF{kappa}B1/Rela dimer translocate to the nucleus and activate target gene transcription, SHP-1 inhibits the phosphorylation of Rela, while its regulation on NF{kappa}B1 has been unknown, especially in pathogen-induced inflammation. Chinese tongue sole, a representative flatfish, has been widely used as a genomics and disease model. Using the teleost and cellular model, we revealed for the first time that SHP-1 inhibits NF{kappa}B1 phosphorylation and nuclear translocation by interacting with NF{kappa}B1, thereby suppressing NF{kappa}B signaling to inhibit bacterial inflammation. In addition, we showed that SHP-1 decreased mortality and alleviated histopathological deterioration, manifested in the inhibition of immune-related pathways and secretion of pro- inflammatory cytokines. Using cellular model, SHP-1 overexpression reduced macrophages M1 polarization, phagocytosis, and oxidative stress, while silencing SHP- 1 exhibited opposite effects. Our findings systematically dissect the functions of SHP- 1 and provide mechanistic insights into the control of inflammation-related diseases. TeaserSHP-1 help maintain the cellular and individual homeostasis by inhibiting the excessive inflammation and immunity via regulating the NF{kappa}B signaling.

immunology↗

bioRxiv2024

FLASH Irradiation Regulates IFN-β induction by mtDNA via Cytochrome c Leakage

Ultrahigh dose rate radiotherapy (FLASH-RT) is under intensive investigation for its biological benefits. The mechanisms underlying its ability to spare normal tissues while suppress tumor growth still remain controversial. Here we reveal that compared to the low dose rate electron irradiation (0.36 Gy/s), FLASH electron irradiation at 61 or 610 Gy/s enhances the cytochrome c leakage from mitochondria in human breast cells MCF-10A, which elicits substantial caspase activation, suppresses both the cytosolic mitochondrial DNA (mtDNA) accumulation and IFN-{beta} secretion. Besides, the deletion of mtDNA severely decreases the radiation-induced cGAS-STING activation. Conversely, the cytochrome c leakage in carcinoma cells MDA-MB-231 post electron irradiation is limited, especially for the case of FLASH irradiation, resulting in less cytosolic cytochrome c but stronger cGAS-STING activation than those in MCF-10A cells. The enhanced difference of cytochrome c leakage between cancer cells and normal cells post FLASH irradiation indicates a potential mechanism of FLASH effect by regulating the apoptotic and inflammatory pathway.

biophysics↗

bioRxiv2024

A tale of two tumors: differential, but detrimental, effects of glioblastoma extracellular vesicles (EVs) on normal human brain cells

Glioblastomas (GBMs) are dreadful brain tumors with abysmal survival outcomes. GBM EVs dramatically affect normal brain cells (largely astrocytes) constituting the tumor microenvironment (TME). EVs from different patient-derived GBM spheroids induced differential transcriptomic, secretomic, and proteomic effects on cultured astrocytes/brain tissue slices as GBM EV recipients. The net outcome of brain cell differential changes nonetheless converges on increased tumorigenicity. GBM spheroids and brain slices were derived from neurosurgical patient tissues following informed consent. Astrocytes were commercially obtained. EVs were isolated from conditioned culture media by ultrafiltration, ultraconcentration, and ultracentrifugation. EVs were characterized by nanoparticle tracking analysis, electron microscopy, biochemical markers, and proteomics. Astrocytes/brain tissues were treated with GBM EVs before downstream analyses. EVs from different GBMs induced brain cells to alter secretomes with pro-inflammatory or TME-modifying (proteolytic) effects. Astrocyte responses ranged from anti-viral gene/protein expression and cytokine release to altered extracellular signal-regulated protein kinase (ERK1/2) signaling pathways, and conditioned media from EV-treated cells increased GBM cell proliferation. Thus, astrocytes/brain slices treated with different GBM EVs underwent non-identical changes in various omics readouts and other assays, indicating "personalized" tumor-specific GBM EV effects on the TME. This raises concern regarding reliance on "model" systems as a sole basis for translational direction. Nonetheless, net downstream impacts from differential cellular and TME effects still led to increased tumorigenic capacities for the different GBMs.

cancer biology↗

bioRxiv2024

Natural variation in salt-induced changes in root:shoot ratio reveals SR3G as a negative regulator of root suberization and salt resilience in Arabidopsis

Soil salinity is one of the major threats to agricultural productivity worldwide. Salt stress exposure alters root and shoot growth rates, thereby affecting overall plant performance. While past studies have extensively documented the effect of salt stress on root elongation and shoot development separately, here we take an innovative approach by examining the coordination of root and shoot growth under salt stress conditions. Utilizing a newly developed tool for quantifying the root:shoot ratio in agar-grown Arabidopsis seedlings, we found that salt stress results in a loss of coordination between root and shoot growth rates. We identify a specific gene cluster encoding domain-of-unknown-function 247 (DUF247), and characterize one of these genes as Salt Root:shoot Ratio Regulator Gene (SR3G). Further analysis elucidates the role of SR3G as a negative regulator of salt stress tolerance, revealing its function in regulating shoot growth, root suberization, and sodium accumulation. We further characterize that SR3G expression is modulated by WRKY75 transcription factor, known as a positive regulator of salt stress tolerance. Finally, we show that the salt stress sensitivity of wrky75 mutant is completely diminished when it is combined with sr3g mutation. Together, our results demonstrate that utilizing root:shoot ratio as an architectural feature leads to the discovery of new stress resilience gene. The studys innovative approach and findings not only contribute to our understanding of plant stress tolerance mechanisms but also open new avenues for genetic and agronomic strategies to enhance crop environmental resilience.

plant biology↗

bioRxiv2024

Chloride Homeostasis Regulates cGAS-STING Signaling

The cGAS-STING signaling pathway has emerged as a key mediator of inflammation. However, the roles of chloride homeostasis on this pathway are unclear. Here, we uncovered a correlation between chloride homeostasis and cGAS-STING signaling. We found that dysregulation of chloride homeostasis attenuates cGAS-STING signaling in a lysosome-independent manner. Treating immune cells with chloride channel inhibitors attenuated 23-cGAMP production by cGAS and also suppressed STING polymerization, leading to reduced cytokine production. We also demonstrate that non-selective chloride channel blockers can suppress the NPC1 deficiency-induced, hyper-activated STING signaling in skin fibroblasts derived from Niemann Pick disease type C (NPC) patients. Our findings reveal that chloride homeostasis majorly affects cGAS-STING pathway and suggest a provocative strategy to dampen STING-mediated inflammation via targeting chloride channels. HighlightsO_LIChloride dysregulation attenuates cGAS-STING signaling in a lysosome-independent manner. C_LIO_LIChloride dysregulation attenuates intracellular 23-cGAMP production. C_LIO_LIChloride dysregulation inhibits STING polymerization and STING-to-IRF3 signaling. C_LIO_LIChloride channel blockers suppress NPC1 deficiency-induced, hyper-activated STING signaling. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=168 SRC="FIGDIR/small/588475v1_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@cf8b59org.highwire.dtl.DTLVardef@1c5859aorg.highwire.dtl.DTLVardef@c6622borg.highwire.dtl.DTLVardef@571646_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2024

Redefining the Game: MVAE-DFDPnet's Low-Dimensional Embeddings for Superior Drug-Protein Interaction Predictions

Precisely predicting drug-protein interactions (DPIs) is pivotal for drug discovery and advancing precision medicine. A significant challenge in this domain is the high-dimensional and heterogeneous data characterizing drug and protein attributes, along with their intricate interactions. In our study, we introduce a novel deep learning architecture: the Multi-view Variational Auto-Encoder embedded within a cascade Deep Forest (MVAE-DFDPnet). This framework adeptly learns ultra-low-dimensional embedding for drugs and proteins. Notably, our t-SNE analysis reveals that two-dimensional embedding can clearly define clusters corresponding to diverse drug classes and protein families. These ultra-low-dimensional embedding likely contribute to the enhanced robustness and generalizability of our MVAE-DFDPnet. Impressively, our model surpasses current leading methods on benchmark datasets, functioning in significantly reduced dimensional spaces. The models resilience is further evidenced by its sustained accuracy in predicting interactions involving novel drugs, proteins, and drug classes. Additionally, we have corroborated several newly identified DPIs with experimental evidence from the scientific literature. The code used to generate and analyze these results can be accessed from https://github.com/Macau-LYXia/MVAE-DFDPnet-V2.

bioinformatics↗

bioRxiv2024

p300/CBP degradation is required to disable the active AR enhanceosome in prostate cancer

Prostate cancer is an exemplar of an enhancer-binding transcription factor-driven disease. The androgen receptor (AR) enhanceosome complex comprised of chromatin and epigenetic coregulators assembles at enhancer elements to drive disease progression. The paralog lysine acetyltransferases p300 and CBP deposit histone marks that are associated with enhancer activation. Here, we demonstrate that p300/CBP are determinant cofactors of the active AR enhanceosome in prostate cancer. Histone H2B N-terminus multisite lysine acetylation (H2BNTac), which is exclusively reliant on p300/CBP catalytic function, marked active enhancers and was notably elevated in prostate cancer lesions relative to the adjacent benign epithelia. Degradation of p300/CBP rapidly depleted acetylation marks associated with the active AR enhanceosome, which was only partially phenocopied by inhibition of their reader bromodomains. Notably, H2BNTac was effectively abrogated only upon p300/CBP degradation, which led to a stronger suppression of p300/CBP-dependent oncogenic gene programs relative to bromodomain inhibition or the inhibition of its catalytic domain. In vivo experiments using an orally active p300/CBP proteolysis targeting chimera (PROTAC) degrader (CBPD-409) showed that p300/CBP degradation potently inhibited tumor growth in preclinical models of castration-resistant prostate cancer and synergized with AR antagonists. While mouse p300/CBP orthologs were effectively degraded in host tissues, prolonged treatment with the PROTAC degrader was well tolerated with no significant signs of toxicity. Taken together, our study highlights the pivotal role of p300/CBP in maintaining the active AR enhanceosome and demonstrates how target degradation may have functionally distinct effects relative to target inhibition, thus supporting the development of p300/CBP degraders for the treatment of advanced prostate cancer.

cancer biology↗

bioRxiv2024

A spectral framework to map QTLs affecting joint differential networks of gene co-expression

Studying the mechanisms underlying the genotype-phenotype association is crucial in genetics. Gene expression studies have deepened our understanding of the genotype [->] expression [->] phenotype mechanisms. However, traditional expression quantitative trait loci (eQTL) methods often overlook the critical role of gene co-expression networks in translating genotype into phenotype. This gap highlights the need for more powerful statistical methods to analyze genotype [->] network [->] phenotype mechanism. Here, we develop a network-based method, called snQTL, to map quantitative trait loci affecting gene co-expression networks. Our approach tests the association between genotypes and joint differential networks of gene co-expression via a tensor-based spectral statistics, thereby overcoming the ubiquitous multiple testing challenges in existing methods. We demonstrate the effectiveness of snQTL in the analysis of three-spined stickleback (Gasterosteus aculeatus) data. Compared to conventional methods, our method snQTL uncovers chromosomal regions affecting gene co-expression networks, including one strong candidate gene that would have been missed by traditional eQTL analyses. Our framework suggests the limitation of current approaches and offers a powerful network-based tool for functional loci discoveries. Significance statementThis work addresses a key gap in understanding the mechanistic foundations for genotype-phenotype associations. While existing expression quantitative trait loci (eQTL) methods identify candidate loci affecting gene expression variants, they often neglect the crucial role of gene co-expression networks. Here, we develop a network-based QTL framework to map genetic loci affecting the gene co-expression network. Utilizing a tensor-based spectral approach, our snQTL method estimates the differential co-expression patterns and effectively identifies the associated genetic loci. Application of snQTL to three-spined sticklebacks revealed candidate loci missed by standard methods. This work suggests the limitations of current approaches and highlights the potential of network-based functional loci discovery.

genetics↗

bioRxiv2024

Distinct Gene Regulatory Dynamics Drive Skeletogenic Cell Fate Convergence During Vertebrate Embryogenesis

Cell type repertoires have expanded extensively in metazoan animals, with some clade-specific cells being paramount to their evolutionary success. A prime example are the skeletogenic cells of vertebrates that form the basis of their developing endoskeletons. Depending on anatomical location, these cells originate from three different embryonic precursor lineages - the neural crest, the somites, and the lateral plate mesoderm - yet they converge developmentally towards similar cellular phenotypes. Furthermore, these lineages have gained skeletogenic competency at distinct timepoints during vertebrate evolution, thus questioning to what extent different parts of the vertebrate skeleton rely on truly homologous cell types. Here, we investigate how lineage-specific molecular properties of the three precursor pools are integrated at the gene regulatory level, to allow for phenotypic convergence towards a skeletogenic cell fate. Using single-cell transcriptomics and chromatin accessibility profiling along the precursor-to-skeletogenic cell continuum, we examine the gene regulatory dynamics associated with this cell fate convergence. We find that distinct transcription factor profiles are inherited from the three precursor states, and that lineage-specific enhancer elements integrate these different inputs at the cis-regulatory level, to execute a core skeletogenic program. We propose a lineage-specific gene regulatory logic for skeletogenic convergence from three embryonic precursor pools. Early skeletal cells in different body parts thus share only a partial deep homology. This regulatory uncoupling may render them amenable to individualized selection, to help to define distinct morphologies and biomaterial properties in the different parts of the vertebrate skeleton.

developmental biology↗

bioRxiv2024

Molecular basis for condensin enrichment at pericentromeres

Faithful chromosome segregation requires packaging of the genome on both global and local scales. Condensin plays a crucial role at pericentromeres to resist spindle forces and ensure the bioriented attachment of kinetochores to microtubules in mitosis. Here we demonstrate that budding yeast condensin is recruited to pericentromeres through a direct interaction between its Ycg1 subunit and the pericentromeric adaptor protein, shugoshin (Sgo1). We identify a Short Linear Motif (SLiM), termed CR1, within the C-terminal region of Sgo1 which inserts into a conserved pocket on Ycg1. Disruption of this interface abolishes the Sgo1-condensin interaction, prevents condensin recruitment to pericentromeres and results in defective sister kinetochore biorientation in mitosis. Similar motifs to CR1 are found in known and potential condensin binding partners and the Ycg1 binding pocket is broadly conserved, including in the mammalian homolog CAP-G. Overall, we uncover the molecular mechanism that targets condensin to define a specialized chromosomal domain.

cell biology↗

bioRxiv2024

Neuroprotective Effects of Bioactive Molecules Derived from Tobacco as Potential Therapeutic Candidates for Alzheimer Disease

Neurodegenerative diseases are significant global health challenges, particularly with an aging population. While tobacco is traditionally linked to health risks, recent studies suggest it may contain compounds beneficial for neurodegenerative conditions. Herein, we explore the potential of bioactive compounds in tobacco as neuroprotective agents for Alzheimers disease (AD). Using genetic engineering, we developed a novel approach with neural progenitor cells (NPCs) derived from embryonic stem cells, equipped with an NF-{kappa}B reporter system to screen tobacco extracts. Our screenings identified three compounds with significant inhibitory effects on NF-{kappa}B activation, a key mediator of neuroinflammation in AD. Among these, rutin exhibited profound neuroprotective effects in an NPC damage model induced by Amyloid-{beta}25-35, reducing apoptotic cell death, enhancing cellular proliferation, and activating critical survival signaling pathways. This modulation underlies rutins anti-inflammatory and neuroprotective activities. Together, our findings support the potential of tobacco-derived compounds in AD therapy and lay the foundation for further exploration of their pharmaceutical value.

pharmacology and toxicology↗

bioRxiv2024

Polyglutamylation of microtubules drives neuronal remodeling

Developmental remodeling shapes neural circuits via activity-dependent pruning of synapses and axons. The cytoskeleton is critical for this process, as microtubule loss via enzymatic severing is an early step of pruning across many circuits and species. However, how microtubule-severing enzymes, such as spastin, are activated in specific neuronal compartments remains unknown. Here, we reveal that polyglutamylation, a posttranslational tubulin modification that is enriched in neurons, plays an instructive role in developmental remodeling by tagging microtubules for severing. Motor neuron-specific gene deletion of enzymes that add or remove tubulin polyglutamylation--TTLL glutamylases vs. CCP deglutamylases--accelerates or delays neuromuscular synapse remodeling in a neurotransmission-dependent manner. This mechanism is not specific to peripheral synapses but also operates in central circuits, e.g., the hippocampus. Thus, tubulin polyglutamylation acts as an activity-dependent rheostat of remodeling and shapes neuronal morphology and connectivity.

cell biology↗

bioRxiv2024

Distinct roles of Nrf1 and Nrf2 in coordinately controlling the anti-ageing response

Cellular senescence has been accepted as a fundamental contributor to ageing and a variety of age-related diseases, in which oxidative stress has been further recognized to play a critical initiation role. However, the anti-senescence potential of antioxidant nuclear factor erythroid-derived 2-like 1 (Nrf1, encoded by Nfe2l1) remains elusive to date, even though the hitherto accumulating evidence demonstrates that it is an indispensable redox-determining transcription factor for maintaining cellular homeostasis and organ integrity. Herein, we discovered that deletion of Nrf1 resulted in markedly elevated senescence characteristics in Nrf1-/- cells, as characterized by two distinct experimental models induced by oxidative stress, which are evinced by typically heightened activity of senescence-associated {beta}-galactosidase and progressive senescence-associated secretory phenotype (SASP), along with decreased cell vitality and intensified cell cycle arrest. Further experimental investigation also uncovered that such acceleration of oxidative stress-induced senescence resulted from heightened disturbance in the cellular homeostasis, because deficiency of Nrf1 leads to the STAG2- and SMC3-dependent chromosomal stability disruption and autophagy dysfunction, though as accompanied by excessive accumulation of Nrf2 (encoded by Nfe2l2). The aberrant hyperactive Nrf2 cannot effectively counteract the escalating disturbance of cellular homeostasis caused by Nrf1-/-. Overall, this study has provided a series of evidence supporting that Nrf1 indeed exerts an essential protective function against oxidative stress-induced cellular senescence, thereby, highlighting its primary indispensable contribution to maintaining robust cell homeostasis.

biochemistry↗

bioRxiv2024

Precision Enhancement of CAR-NK Cells through Non-Viral Engineering and Highly Multiplexed Base Editing

Natural killer (NK) cells unique ability to kill transformed cells expressing stress ligands or lacking major histocompatibility complexes (MHC) has prompted their development for immunotherapy. However, NK cells have demonstrated only moderate responses against cancer in clinical trials and likely require advanced genome engineering to reach their full potential as a cancer therapeutic. Multiplex genome editing with CRISPR/Cas9 base editors (BE) has been used to enhance T cell function and has already entered clinical trials but has not been reported in human NK cells. Here, we report the first application of BE in primary NK cells to achieve both loss-of-function and gain-of-function mutations. We observed highly efficient single and multiplex base editing, resulting in significantly enhanced NK cell function. Next, we combined multiplex BE with non-viral TcBuster transposon-based integration to generate IL-15 armored CD19 CAR-NK cells with significantly improved functionality in a highly suppressive model of Burkitts lymphoma both in vitro and in vivo. The use of concomitant non-viral transposon engineering with multiplex base editing thus represents a highly versatile and efficient platform to generate CAR-NK products for cell-based immunotherapy and affords the flexibility to tailor multiple gene edits to maximize the effectiveness of the therapy for the cancer type being treated.

bioengineering↗

bioRxiv2024

DR5 disulfide bonding as a sensor and effector of protein folding stress

New agents are needed that selectively kill cancer cells without harming normal tissues. The TRAIL ligand and its receptors, DR5 and DR4, exhibit cancer-selective toxicity, but TRAIL analogs or agonistic antibodies targeting these receptors have not received FDA approval for cancer therapy. Small molecules for activating DR5 or DR4 independently of protein ligands may bypass some of the pharmacological limitations of these protein drugs. Previously described Disulfide bond Disrupting Agents (DDAs) activate DR5 by altering its disulfide bonding through inhibition of the Protein Disulfide Isomerases (PDIs) ERp44, AGR2, and PDIA1. Work presented here extends these findings by showing that disruption of single DR5 disulfide bonds causes high-level DR5 expression, disulfide-mediated clustering, and activation of Caspase 8-Caspase 3 mediated pro-apoptotic signaling. Recognition of the extracellular domain of DR5 by various antibodies is strongly influenced by the pattern of DR5 disulfide bonding, which has important implications for the use of agonistic DR5 antibodies for cancer therapy. Disulfide-defective DR5 mutants do not activate the ER stress response or stimulate autophagy, indicating that these DDA-mediated responses are separable from DR5 activation and pro-apoptotic signaling. Importantly, other ER stressors, including Thapsigargin and Tunicamycin also alter DR5 disulfide bonding in various cancer cell lines and in some instances, DR5 mis-disulfide bonding is potentiated by overriding the Integrated Stress Response (ISR) with inhibitors of the PERK kinase or the ISR inhibitor ISRIB. These observations indicate that the pattern of DR5 disulfide bonding functions as a sensor of ER stress and serves as an effector of proteotoxic stress by driving extrinsic apoptosis independently of extracellular ligands.

cancer biology↗

bioRxiv2024

The segmented flavivirus Alongshan virus reduces mitochondrial mass via degrading STAT2 to suppress innate immune response

Alongshan virus (ALSV) is a newly discovered pathogen of the Flaviviridae family, characterized by a multi-segmented genome distantly related to the canonical flaviviruses. Understanding the pathogenic mechanism of the emerging segmented flavivirus is crucial for the development of intervention strategies. Here we show that ALSV can infect multiple mammalian cells and induces the expression of antiviral genes. Moreover, ALSV is sensitive to IFN-{beta} and possesses the ability to counteract type I IFN response. Mechanistically, ALSVs nonstructural protein NSP1 binds to and degrades human STAT2 through an autophagy pathway in a species-dependent manner, resulting in direct inhibition of the expression of interferon-stimulated genes (ISGs). Specifically, NSP1 methyltransferase domain binds to the key sites of F175/R176 located in coiled-coil domain of STAT2. Moreover, NSP1-mediated degradation of STAT2 results in a reduction in mitochondrial mass by disrupting mitochondrial dynamics to induce mitophagy and inhibiting mitochondrial biogenesis, thereby suppressing the innate immune response. Interestingly, inhibiting mitophagy using 3-Methyladenine and enhancing mitochondrial biogenesis using the PPAR{gamma} agonist pioglitazone can reverse NSP1-mediated inhibition of ISGs, suggesting that promoting mitochondrial mass presents an effective antiviral strategy. Our findings elucidate the intricate regulatory crosstalk between ALSV and the hosts innate immune response, providing valuable insights into the pathogenesis and intervention strategy of emerging segmented flavivirus.

microbiology↗

bioRxiv2024

Human brain aging heterogeneity observed from multi-region omics data reveals a subtype closely related to Alzheimer's disease

INTRODUCTION: The interconnection between brain aging and Alzheimers disease (AD) remain to be elucidated. METHODS: We investigated multi-omics (transcriptomics and proteomics) data from multiple brain regions (i.e., the hippocampus (HIPP), prefrontal cortex (PFC), and cerebellum (CRBL)) in cognitively normal individuals. RESULTS: We found that brain samples could be divided into ADL (AD-like) and NL (normal) subtypes which were correlated across brain regions. The differentially expressed genes in the ADL samples highly overlapped with AD gene signatures and the changes were consistent across brain regions (PFC and HIPP) in the multi-omics data. Intriguingly, the ADL subtype in PFC showed more differentially expressed genes than other brain regions, which could be explained by the baseline gene expression differences in the PFC NL samples. DISCUSSION: We conclude that brain aging heterogeneity widely exists, and our findings corroborate with the hypothesis that AD-related changes occur decades before the clinical manifestation of cognitive impairment in a sub-population.

neuroscience↗

bioRxiv2024

Two-photon imaging of excitatory and inhibitory neural response to infrared neural stimulation

SignificancePulsed infrared neural stimulation (INS, 1875 nm) is an emerging neurostimulation technology that delivers focal pulsed heat to activate functionally specific mesoscale networks and holds promise for clinical application. However, little is known about its effect on excitatory and inhibitory cell types in cerebral cortex. AimEstimates of summed population neuronal response timecourses provide a potential basis for neural and hemodynamic signals described in other studies. ApproachUsing two-photon calcium imaging in mouse somatosensory cortex, we have examined the effect of INS pulse train application on hSyn neurons and mDlx neurons tagged with GCaMP6s. ResultsWe find that, in anesthetized mice, each INS pulse train reliably induces robust response in hSyn neurons exhibiting positive going responses. Surprisingly, mDlx neurons exhibit negative going responses. Quantification using the index of correlation illustrates responses are reproducible, intensity-dependent, and distance-dependent. Also, a contralateral activation is observed when INS application. ConclusionsIn sum, the population of neurons stimulated by INS includes both hSyn and mDlx neurons; within a range of stimulation intensities, this leads to overall excitation in the stimulated population, leading to the previously observed activations at distant post-synaptic sites.

neuroscience↗