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Ding, Y.

Publications and source records attributed to Ding, Y..

At least 199 records · Page 11Linked to original sources

Reversible and gain modulation of neuronal responses and sensorimotor behavior by mid-infrared stimulation

Neuromodulation serves as a cornerstone for brain sciences and clinical applications. Mid-infrared stimulation (MIRS) has been recently reported to cause non-thermal modulation of brain functions. However little knowledge of mechanisms hampers its application. Here we bridge across ion channels, neuronal signals, and behavioral performances associated with sensorimotor transformation to provide evidence of how the alternation of neuronal activity by MIRS guides the change of behavioral performance in awake-behaving pigeons. We compared effects on visually-guided eye movements by applying MIRS and electrical stimulation (ES) in the pretectal nucleus lentiformis mesencephali (nLM). Distinct from ES, we found a specific gain modulation of MIRS to alter behavior in a manner of the strength of visual inputs. Our simultaneous extracellular recordings showed that MIRS can excite and inhibit the neuronal activity in the same pretectal neuron based on its ongoing sensory responsiveness levels in awake-behaving animals. We further applied computational simulations and found that MIRS can modulate the carbonyl group (-C=O) enriched on the potassium channel to resonate, and could affect action potential generation, alter neuronal responses to sensory inputs and then guide behavior. Our findings suggest that MIRS could be a promising approach for brain researches and neurological diseases, with gene free manipulation.

neuroscience↗

Drug design and repurposing with a sequence-to-drug paradigm

Drug development based on target proteins has been a successful approach in recent decades. A conventional structure-based drug design pipeline is a complex, human-engineered pipeline with multiple independently optimized steps. Advances in end-to-end differentiable learning suggest the potential benefits of similarly reformulating drug design. Here, we proposed a new sequence-to-drug paradigm that discovers drug-like small-molecule modulators directly from protein sequences and validated this concept for the first time in three stages. First, we designed TransformerCPI2.0 as a core tool for the sequence-to-drug paradigm, which exhibited competitive performance with conventional structure-based drug design approaches. Second, we validated the binding knowledge that TransformerCPI2.0 has learned. Third, we applied a sequence-to-drug paradigm to discover new hits for E3 ubiquitin-protein ligases: speckle-type POZ protein (SPOP), ring finger protein 130 (RNF130) which does not have a 3D structure, and repurposed proton pump inhibitors (PPIs) for ADP-ribosylation factor 1 (ARF1). This first proof of concept shows that the sequence-to-drug paradigm is a promising direction for drug development.

molecular biology↗

Optimized high-throughput screening of non-coding variants identified from genome-wide association studies

The vast majority of disease-associated single nucleotide polymorphisms identified from genome-wide association study (GWAS) are localized in non-coding regions. A significant fraction of these variants impact transcription factors binding to enhancer elements and alter gene expression. To functionally interrogate the activity of such variants we developed snpSTARRseq, a high-throughput experimental method that can interrogate the functional impact of hundreds to thousands of non-coding variants on enhancer activity. snpSTARRseq dramatically improves signal-to-noise by utilizing a novel sequencing and bioinformatic approach that increases both insert size and number of variants tested per loci. Using this strategy, we interrogated 70 of 140 known prostate cancer (PCa) risk-associated loci and demonstrated that 26 (37%) of them harbor 36 SNPs that significantly altered enhancer activity. Combining these results with chromosomal looping data we could identify interacting genes and provide a mechanism of action for 20 PCa GWAS risk regions. When benchmarked to orthogonal methods, snpSTARRseq showed a strong correlation with in vivo experimental allelic-imbalance studies whereas there was no correlation with predictive in silico approaches. Overall, snpSTARRseq provides an integrated experimental and computational framework to functionally test non-coding genetic variants.

genetics↗

Fish oil Nano-emulsion Kills Macrophage: Ferroptosis and Autophagy Triggered by Catalase-catalysed Superoxide Eruption

Fish oil is increasingly utilized in the form of nano-emulsion as nutrient and function fortifier. The nano-emulsions high polyunsaturated fatty acids content and electron donors at oil/water interface could be a potential site of redox reaction, if a previously unrecognised trigger was provided. Here we report that a vigorous superoxide production occurred in fish oil nano-emulsion in the presence of mammalian catalase in both acellular and cellular systems. Furthermore, the resulting superoxide increased cytosolic ROS and membrane lipid peroxidation of murine macrophage, and eventually caused fatal oxidative damage, which involves autophagy and ferroptosis but not apoptosis. The cell death was significantly inhibited by a catalase-specific inhibitor. The ferroptosis was independent of protease Caspase-3 activation or glutathione peroxidase suppression. Our findings discover a hidden risk factor of the widely acclaimed fish oil emulsion and suggest a novel mechanism of cellular damage by dietary lipids on mucosal layer of the alimentary tract.

cell biology↗

A snapshot of the root phenotyping landscape in 2021

Root phenotyping describes methods for measuring root properties, or traits. While root phenotyping can be challenging, it is advancing quickly. In order for the field to move forward, it is essential to understand the current state and challenges of root phenotyping, as well as the pressing needs of the root biology community. In this letter, we present and discuss the results of a survey that was created and disseminated by members of the Graduate Student and Postdoc Ambassador Program at the 11th symposium of the International Society of Root Research. This survey aimed to (1) provide an overview of the objectives, biological models and methodological approaches used in root phenotyping studies, and (2) identify the main limitations currently faced by plant scientists with regard to root phenotyping. Our survey highlighted that (1) monocotyledonous crops dominate the root phenotyping landscape, (2) root phenotyping is mainly used to quantify morphological and architectural root traits, (3) 2D root scanning/imaging is the most widely used root phenotyping technique, (4) time-consuming tasks are an important barrier to root phenotyping, (5) there is a need for standardised, high-throughput methods to sample and phenotype roots, particularly under field conditions, and to improve our understanding of trait-function relationships.

scientific communication and education↗

A phenotype-based forward genetic screen identifies Dnajb6 as a sick sinus syndrome gene

Sick sinus syndrome (SSS) is a group of heart rhythm disorders caused by malfunction of the sinus node, the hearts primary pacemaker. Partially owing to its aging-associated phenotypic manifestation and low expressivity, molecular mechanisms of SSS remain difficult to decipher. Here, we aim to develop a phenotype-based forward genetic approach in the zebrafish (Danio rerio) animal model for discovering essential genes which dysfunction could result in SSS-like phenotypes. Previously we showed the generation of protein trap library by using a revertible gene-breaking transposon (GBT)-based insertional mutagenesis system. Here, we reported the generation of a collection of 35 zebrafish insertional cardiac lines derived from this protein trap library, which was screened using electrocardiographic measurements. As a result, three mutants with SSS-like phenotypes were identified. We then focused on one of these 3 GBT mutants called GBT411 in which dnajb6b gene was disrupted, and conducted expressional, genetic, transcriptome, and electrophysiological studies using both zebrafish and mouse models. These studies confirmed the identity of Dnajb6 as a novel SSS causative gene with a unique expression pattern within the specialized population of sinus node pacemaker cardiomyocytes that lack the expression of HCN4 channels. Together, this study demonstrates the feasibility of a genetic screening approach in an adult vertebrate animal model for discovering new genetic factors for a heart rhythm disorder such as SSS.

genetics↗

Harringtonine has the effects of double blocking SARS-CoV-2 membrane fusion

Fusion with host cell membrane is the main mechanism of infection of SARS-CoV-2. Here, we propose a new strategy to double block SARS-CoV-2 membrane fusion by using Harringtonine (HT), a small-molecule antagonist. By using cell membrane chromatography (CMC), we found that HT specifically targeted the SARS-CoV-2 S protein and host cell TMPRSS2, and then confirmed that HT can inhibit pseudotyped virus membrane fusion. Furthermore, HT successfully blocked SARS-CoV-2 infection, especially in the delta and Omicron mutant. Since HT is a small-molecule antagonist, it is minimally affected by the continuous variation of SARS-CoV-2. Our findings show that HT is a potential small-molecule antagonist with a new mechanism of action against SARS-CoV-2 infection, and thus HT mainly targets the S protein, and thus, greatly reduces the damage of the S proteins autotoxicity to the organ system, has promising advantages in the clinical treatment of COVID-19.

pharmacology and toxicology↗

A reference single-cell regulomic and transcriptomic map of cynomolgus monkeys

Non-human primates (NHP) are attractive laboratory animal models that accurately reflect both developmental and pathological features of humans. Here we present a compendium of cell types from the cynomolgus monkey Macaca fascicularis (denoted as Monkey Atlas) using both single-cell chromatin accessibility (scATAC-seq) and RNA sequencing (scRNA-seq) data at the organism-wide level. The integrated cell map enables in-depth dissection and comparison of molecular dynamics, cell-type composition and cellular heterogeneity across multiple tissues and organs. Using single-cell transcriptomic data, we inferred pseudotime cell trajectories and cell-cell communications to uncover key molecular signatures underlying their cellular processes. Furthermore, we identified various cell-specific cis-regulatory elements and constructed organ-specific gene regulatory networks at the single-cell level. Finally, we performed a comparative analysis of single-cell landscapes among mouse, cynomolgus monkey and human, and we showed that cynomolgus monkey has significantly higher degree of cell-type similarity to human than mouse. Taken together, our study provides a valuable resource for NHP cell biology.

bioinformatics↗

Traditional martial arts and shooting training have different effects on auditory fine structure processing ability---Evidence from behavioral tests and fMRI

Explore the influence of traditional martial arts and shooting training on the ability of auditory temporal fine structure (TFS) processing. Twenty-five college students participated in the experiment, including 8 traditional martial arts practitioners, 8 high-level shooting athletes, and 9 control groups without any regular exercise habits. The BIC (break in interaural correlation) delay threshold and TFS1 test were used to evaluate the temporary storage capacity and sensitivity of TFS, respectively, and a fMRI test was performed after the test. The results found that the traditional martial arts group had stronger TFS sensitivity, while the shooting group had stronger TFS retention ability, and the performance of the behavioral test of the shooting group is related to the fALFF value of the brain area of interest. Traditional martial arts and shooting training have improved the ability of auditory information processing from different angles, diversified exercise habits will lead to the development of diversity in brain structure and function.

neuroscience↗

Identification of a promiscuous conserved CTL epitope within the SARS-CoV-2 spike protein

The COVID-19 disease caused by infection with SARS-CoV-2 and its variants is devastating to the global public health and economy. To date, over a hundred COVID-19 vaccines are known to be under development and the few that have been approved to fight the disease are using the spike protein as the primary target antigen. Although virus neutralizing epitopes are mainly located within the RBD of the spike protein, the presence of T cell epitopes, particularly the CTL epitopes that are likely to be needed for killing infected cells, has received comparatively little attention. In this study, we predicted several potential T cell epitopes with web-based analytic tools, and narrowed them down from several potential MHC-I and MHC-II epitopes by ELIspot and cytolytic assays to a conserved MHC-I epitope. The epitope is highly conserved in current viral variants including the most recent Omicron and compatible with presentation by most HLA alleles worldwide. In conclusion, we identified a CTL epitope suitable for evaluating the CD8+ T cell-mediated cellular response and potentially for addition into future COVID-19 vaccine candidates to maximize CTL responses against SARS-CoV-2.

immunology↗

An instance-specific causal framework for learning intercellular communication networks that define microenvironments of individual tumors

Cells within a tumor microenvironment (TME) dynamically communicate and influence each others cellular states through an intercellular communication network (ICN). In cancers, intercellular communications underlie immune evasion mechanisms of individual tumors. We developed an individualized causal analysis framework for discovering tumor-specific ICNs. Using head and neck squamous cell carcinoma (HNSCC) tumors as a testbed, we first mined single-cell RNA-sequencing data to discover gene expression modules (GEMs) that reflect the states of transcriptomic processes within tumor and stromal single cells. By deconvoluting bulk transcriptomes of HNSCC tumors profiled by The Cancer Genome Atlas (TCGA), we estimated the activation states of these transcriptomic processes in individual tumors. Finally, we applied individualized causal network learning to discover an ICN within each tumor. Our results show that cellular states of cells in TMEs are coordinated through ICNs that enable multi-way communications among epithelial, fibroblast, endothelial, and immune cells. Further analyses of individual ICNs revealed structural patterns that were shared across subsets of tumors, leading to the discovery of 4 different subtypes of networks that underlie disparate TMEs of HNSCC. Patients with distinct TMEs exhibited significantly different clinical outcomes. Our results show that the capability of estimating individual ICNs reveals heterogeneity of ICNs and sheds light on the importance of intercellular communication in impacting disease development and progression.

cancer biology↗

Discovery of a conserved rule behind the assembly of β-barrel membrane proteins.

Outer membrane proteins (OMPs) are essential components of the outer membrane of Gram-negative bacteria. In terms of protein targeting and assembly, the current dogma holds that a "{beta}-signal" imprinted in the final {beta}-strand of the OMP engages the {beta}-barrel assembly machinery (BAM complex) to initiate membrane insertion and assembly of the OMP into the outer membrane. Here, we revealed an additional rule, that signals equivalent to the {beta}-signal are repeated in other, internal {beta}-strands within bacterial OMPs, by peptidomimetic and mutational analysis. The internal signal is needed to promote the efficiency of the assembly reaction of these OMPs. BamD, an essential subunit of the BAM complex, recognizes the internal signal and the {beta}-signal, arranging several {beta}-strands and partial folding for rapid OMP assembly. The internal signal-BamD ordering system is not essential for bacterial viability but is necessary to retain the integrity of the outer membrane against antibiotics and other environmental insults. TEASERBacterial outer membrane proteins are recognized and bound by BamD at specific signals located in multiple {beta}-strands at the C-terminus of these proteins.

biochemistry↗

seRNA PAM-1 regulates skeletal muscle satellite cell activation and aging through trans regulation of Timp2 expression synergistically with Ddx5

Muscle satellite cells (SCs) are responsible for muscle homeostasis and regeneration; and lncRNAs play important roles in regulating SC activities. Here in this study, we identify PAM-1 (Pax7 Associated Muscle lncRNA) that is induced in activated SCs to promote SC activation into myoblast cells upon injury. PAM-1 is generated from a myoblast specific super-enhancer (SE); as a seRNA it binds with a number of target genomic loci predominantly in trans. Further studies demonstrate that it interacts with Ddx5 to tether PAM-1 SE to it inter-chromosomal targets Timp2 and Vim to activate the gene expression. Lastly, we show that PAM-1 expression is increased in aging SCs, which leads to enhanced inter-chromosomal interaction and target genes up-regulation. Altogether, our findings identify PAM-1 as a previously unknown lncRNA that regulates both SC activation and aging through its trans gene regulatory activity.

developmental biology↗

Metabolite profiling reveals organ-specific flavone accumulation in Scutellaria and identifies a scutellarin isomer isoscutellarein 8-O-β-glucuronopyranoside

Scutellaria is a genus of plants containing multiple species with well-documented medicinal effects. S. baicalensis and S. barbata are among the best-studied Scutellaria species, and previous works have established flavones to be the primary source of their bioactivity. Recent genomic and biochemical studies with S. baicalensis and S. barbata have advanced our understanding of flavone biosynthesis in Scutellaria. However, as over several hundreds of Scutellaria species occur throughout the world, flavone biosynthesis in most species remains poorly understood. In this study, we analyzed organ-specific flavone profiles of seven Scutellaria species, including S. baicalensis, S. barbata and two species native to the Americas (S. wrightii to Texas and S. racemosa to Central and South America). We found that the roots of almost all these species produce only 4-deoxyflavones, while 4-hydroxyflavones are accumulated exclusively in their aerial parts. On the other hand, S. racemosa and S. wrightii also accumulated high levels of 4-deoxyflavones in their aerial parts, different with the flavone profiles of S. baicalensis and S. barbata. Furthermore, our metabolomics and NMR study identified the accumulation of isoscutellarein 8-O-{beta}-glucuronopyranoside, a rare 4-hydroxyflavone, in the stems and leaves of several Scutellaria species including S. baicalensis and S. barbata, but not in S. racemosa and S. wrightii. Distinctive organ-specific metabolite profiles among Scutellaria species indicate the selectivity and diverse physiological roles of flavones.

plant biology↗

Rapamycin attenuated zinc-induced tau phosphorylation and oxidative stress in animal model: Involvement of dual mTOR/p70S6K and Nrf2/HO-1 pathways

Alzheimers disease is pathologically featured by abnormal accumulation of amyloid-beta plaque, neurofibrillary tangles, oxidative stress, neuroinflammation, and neurodegeneration. Metal dysregulation including excessive zinc released by presynaptic neurons plays an important role in tau pathology and oxidase activation. The activities of mammalian target of rapamycin (mTOR)/ ribosomal S6 protein kinase (p70S6K) are elevated in the brains of patients with Alzheimers disease. Zinc induces tau hyperphosphorylation via mTOR/P70S6K activation in vitro. However, the involvement of mTOR/P70S6K pathway in zinc-induced oxidative stress, tau degeneration, synaptic and cognitive impairment, has not been fully elucidated in vivo. Here we assessed in the effect of pathological concentration of zinc in SH-SY5Y cells by using biochemical assays and immunofluorescence staining. Rats (n = 18, male) were lateral ventricularly-injected with zinc and treated with rapamycin (intraperitoneal injection) for one week and assessed using Morris water maze. Evaluation of the oxidative stress, tau phorsphylation and synaptic impairment were performed using the hippocampus tissue of the rats by biochemical assays and immunofluorescence staining. Results from Morris water maze showed that the capacity of spatial memory is impaired in zinc-treated rats. Zinc sulfate significantly increased the levels of P-mTOR Ser2448, P-p70S6K Thr389, and P-tau Ser356, and decreased levels of Nrf2 and HO{square}1 in SH-SY5Y cells and in zinc-treated rats compared with control groups. Increased expressions of reactive oxygen species were observed in zinc sulfate-induced SH-SY5Y cells as well as in the hippocampus of zinc-injected rats. Rapamycin, an inhibitor of mTOR, rescued the zinc-induced increases in mTOR/p70S6K activations, tau phosphorylation and oxidative stress, as well as Nrf2/HO{square}1 inactivation, cognitive impairment and synaptic impairment reduced the expression of synapse-related proteins in zinc-injected rats. In conclusion, our findings imply that rapamycin prevents zinc-induced cognitive impairment and protects neurons from tau pathology, oxidative stress and synaptic impairment, by decreasing mTOR/p70S6K hyperactivity and increasing Nrf2/HO {square} 1 activity.

neuroscience↗

The chromatin-remodeling enzyme Smarca5 regulates erythrocyte aggregation via Keap1-Nrf2 signaling

Although thrombosis has been extensively studied using various animal models, however, our understanding of the underlying mechanism remains elusive. Here, using zebrafish model, we demonstrated that smarca5-deficient red blood cells (RBCs) formed blood clots in the caudal vein plexus that mimics venous thrombosis. We further used the anti-thrombosis drugs to treat smarca5zko1049a embryos and found that a thrombin inhibitor, argatroban, partially prevented blood clot formation in smarca5zko1049a. To explore the regulatory mechanism of smarca5 in RBC homeostasis, we profiled the chromatin accessibility landscape and transcriptome features in RBCs from smarca5zko1049a and their siblings and found that both the chromatin accessibility at the keap1a promoter and expression of keap1a were decreased. Keap1 is a suppressor protein of Nrf2, which is a major regulator of oxidative responses. We further identified that the expression of hmox1a, a downstream target of Keap1-Nrf2 signaling pathway, was markedly increased upon smarca5 deletion. Importantly, overexpression of keap1a or knockdown of hmox1a partially rescued the blood clot formation, suggesting that the disrupted Keap1-Nrf2 signaling is responsible for the venous thrombosis-like phenotypes in smarca5 mutants. Together, our study using zebrafish smarca5 mutants not only characterizes a novel role for smarca5 in blood clot formation, but also provides a new venous thrombosis animal model to support drug screening and pre-clinical therapeutic assessments to treat thrombosis.

developmental biology↗

A Wide-Field Micro-Computed Tomography Detector: Micron Resolution at Half-centimeter Scale

Ideal 3-dimensional imaging of many complex samples, such as biological tissues made up of micro-scale structures extending over millimeter- to centimeter-scale tissue samples and organisms, requires both a wide field-of-view and high resolution. With existing optics and detectors used for micro-CT imaging, sub-micron pixel resolution can only be achieved for fields-of-view of <2 mm. This manuscript presents a unique detector system with a 6-mm field-of-view image circle and 0.5 m pixel size that can be used in both synchrotron facilities and tabletop micro-CT units. A resolution-test pattern with linear microstructures and whole adult Daphnia magna were imaged on Beamline 8.3.2 of the Advanced Light Source. Volumes of 10,000 x 10,000 x 7,096 isotropic 0.5 m voxels were reconstructed over a 5.0 x 3.5 mm field-of-view. Measurements in the projection domain confirmed a 1.182 m measured spatial resolution that is largely Nyquist-limited. This unprecedented combination of field-of-view and resolution dramatically reduces the need for sectional scans and computational stitching for large samples, ultimately offering the means to elucidate change in tissue and cellular morphology in the context of larger whole, intact model organisms and specimens. This development is also anticipated to benefit micro-CT imaging in materials science, microelectronics, agricultural science, and biomedical engineering. SynopsisA custom wide-field lens and a new-generation megapixel camera enabled microCT scanning over a 3.5 x 5 mm field-of-view at a 1 m resolution / 0.5 m pixel size at the Berkeley Lawrence Advanced Light Source using a phantom with micron scale features. This novel combination of resolution and field-of-view will be broadly applicable to any setting in which micron-scale structures need to be characterized comprehensively in 3 dimensions over mm to cm scale.

bioinformatics↗

Stromal-cell deletion of STAT3 protects mice from kidney fibrosis by inhibiting pericytes trans-differentiation and migration

Signal transducer and activator of transcription 3 (STAT3) is a key transcription factor implicated in the pathogenesis of kidney fibrosis. Although tubular Stat3 deletion in tubular epithelial cells is known to protect mice from kidney fibrosis, the exact function of STAT3 in stromal cells remains unknown. We utilized stromal-cell Stat3 knock-out (KO) mice, CRISPR and pharmacologic activators and inhibitors of STAT3 to investigate its function in pericyte-like cells. STAT3 is phosphorylated in tubular epithelial cells in acute kidney injury whereas its activation expanded to interstitial cells in chronic kidney disease in mice and humans. Stromal cell-specific deletion of Stat3 protects mice from folic acid- and aristolochic acid-induced kidney fibrosis. Mechanistically, STAT3 directly regulates the inflammatory pathway, differentiation of pericytes into myofibroblasts. Specifically, STAT3 activation leads to an increase in migration and profibrotic signaling in genome-edited pericyte-like cells, 10T1/2. Conversely, Stat3 KO or blocking STAT3 function inhibits detachment, spreading, migration, and profibrotic signaling. Furthermore, STAT3 binds to Collagen1a1 promoter of fibrotic mouse kidneys and in pericyte-like cells. Together, our study identifies a previously unknown function of STAT3 in stromal cells that promotes kidney fibrosis and may have therapeutic value in fibrotic kidney disease. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=73 SRC="FIGDIR/small/456872v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@35dcbforg.highwire.dtl.DTLVardef@2fc055org.highwire.dtl.DTLVardef@fc0d92org.highwire.dtl.DTLVardef@1def2e6_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗