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Cheng, Y.

Publications and source records attributed to Cheng, Y..

At least 199 records · Page 11Linked to original sources

Drug Reinforcement Impairs Cognitive Flexibility by Inhibiting Striatal Cholinergic Neurons

The mechanisms underlying the reduction in cognitive flexibility associated with reinforcement of addictive substance use are unknown. This reinforcement is mediated by substance-induced synaptic plasticity in direct-pathway medium spiny neurons (dMSNs) that project to the substantia nigra (SNr). Cognitive flexibility is mediated by cholinergic interneurons (CINs), which receive extensive local inhibition from the striatum. Here, we report that cocaine or alcohol administration caused a long-lasting potentiation of local inhibitory dMSN[->]CIN transmission in the dorsomedial striatum (DMS), a brain region critical for goal-directed behavior and cognitive flexibility. This dMSN[->]CIN potentiation reduced CIN firing activity. Furthermore, chemogenetic and time-locked optogenetic inhibition of DMS CINs suppressed cognitive flexibility in an instrumental reversal learning task. Importantly, rabies-mediated tracing and physiological studies revealed that SNr-projecting dMSNs, which mediate reinforcement, sent axonal collaterals to inhibit DMS CINs, which mediate flexibility. Our findings demonstrate that the local inhibitory dMSN[->]CIN circuit mediates a reinforcement-induced reduction in cognitive flexibility. HIGHLIGHTSO_LICocaine reinforcement inhibits striatal cholinergic interneurons (CINs) and impairs cognitive flexibility. C_LIO_LIOptogenetic and chemogenetic CIN inhibition impairs cognitive flexibility. C_LIO_LIReinforcement behaviors potentiate inhibitory transmission from direct-pathway medium spiny neurons (dMSNs) to CINs. C_LIO_LISubstantia nigra-projecting dMSNs mediate reinforcement and also send collaterals that inhibit CINs. C_LI

neuroscience↗

Multi-trait genome-wide association analyses leveraging alcohol use disorder findings identify novel loci for smoking behaviors in the Million Veteran Program

Smoking behaviors and alcohol use disorder (AUD), moderately heritable traits, commonly co-occur in the general population. Single-trait genome-wide association studies (GWAS) have identified multiple loci for smoking and AUD. However, GWASs that have aimed to identify loci contributing to comorbid smoking and AUD have used small samples and thus have not been highly informative. Applying multi-trait analysis of GWASs (MTAG), we conducted a joint GWAS of smoking and AUD with data from the Million Veteran Program (N=318,694). By leveraging GWAS summary statistics for AUD, MTAG identified 21 genome-wide significant (GWS) loci associated with smoking initiation and 18 loci associated with smoking cessation compared to 16 and 8 loci, respectively, identified by single-trait GWAS. The novel loci for smoking behaviors identified by MTAG included those previously associated with psychiatric or substance use traits. Colocalization analysis identified 10 loci shared by AUD and smoking status traits, all of which achieved GWS in MTAG, including variants on SIX3, NCAM1, and near DRD2. Functional annotation of the MTAG variants highlighted biologically important regions on ZBTB20, DRD2, PPP6C, and GCKR that contribute to smoking behaviors. In contrast, MTAG of smoking behaviors and alcohol consumption (AC) did not enhance discovery compared with single-trait GWAS for smoking behaviors. We conclude that using MTAG to augment the power of GWAS enables the identification of novel genetic variants for commonly comorbid phenotypes, providing new insights into their pleiotropic effects on smoking behavior and AUD.

genetics↗

Taming the data deluge: a novel end-to-end deep learning framework for classifying marine biological and environmental images

Marine underwater imaging facilitates non-destructive sampling of species at frequencies, durations, and accuracies that are unattainable by conventional sampling methods. These systems necessitate complex automated processes to identify organisms efficiently, however, current frameworks struggle to disentangle ecological foreground components from their dispensable background content. Underwater image processing relies on common architecture: namely image binarization for segmenting potential targets, prior to information extraction and classification by deep learning models. While intuitive, this infrastructure underperforms as it has difficulty in handling: high concentrations of biotic and abiotic particles, rapid changes in dominant taxa, and target sizes that vary by several orders of magnitude. To overcome these issues, a new framework is presented that begins with a scene classifier to capture large within-image variation, such as disparities in particle concentration and dominant taxa. Following scene classification, scene-specific regional convolutional neural network (Mask R-CNN) models were trained to separate target objects into different taxonomic groups. The procedure allows information to be extracted from different image types, while minimizing potential bias for commonly occurring features. Using in situ coastal PlanktonScope images, we compared the scene-specific models to the Mask R-CNN model including all scene categories without scene classification, defined as the full model, and found that the scene-specific approach outperformed the full model with >20% accuracy in noisy images. The full model missed up to 78% of the dominant taxonomic groups, such as Lyngbya, Noctiluca, and Phaeocystis colonies. This performance improvement is due to the scene classifier, which reduces the variation among images and allows an improved match between the observed taxonomic groups and the taxonomic groups in pre-trained models. We further tested the framework on images from a benthic video camera and an imaging sonar system. Results demonstrate that the procedure is applicable to different types of underwater images and achieves significantly more accurate results than the full model. Given that the unified framework is neither instrument nor ecosystem-specific, the proposed model facilitates deployment throughout the marine biome.

ecology↗

Manipulating Oxalate Decarboxylase Provides the Basis of Antilithic Therapy by Acting on the Gut Microbiota

A high concentration of oxalate is associated with an increased risk of kidney calcium oxalate (CaOx) stones, and the degradation of exogenous oxalate mainly depends on oxalate-degrading enzymes from the intestinal microbiome. We found that Zinc Gluconate supplement to patients with CaOx kidney stones could significantly improve the abundance of oxalate metabolizing bacteria in human body through clinical experiments on the premise of simultaneous antibiotic treatment and the imbalance of Lactobacillus and OxDC was involved in CaOx kidney stones through clinical sample analysis. Then, we identified that Zn2+ could be used as an external factor to improve the activity of OxDC and protect Lactobacillus, achieved the preventive effect on rats with stones aggravated by antibiotics. Finally, by analyzing the three-dimensional structure of OxDC and some in vitro experiments, we propose a hypothesis Zn2+ increases the metabolism of oxalate in humans through its positive effects on Lactobacillus and OxDC to reduce CaOx kidney stone symptoms in rats. IMPORTANCEUrinary stone disease is one of the most common urological disorders, and 70%-80% of urinary stones are calcium oxalate (CaOx) stones. We found the structural basis and metabolic mechanism by which oxalate decarboxylase metabolizes oxalate were elucidated, and Zn2+ was illustrated to have therapeutic effects on CaOx stones by improving the tolerance of Lactobacillus to antibiotics. According to that, proper Zn2+ levels in the diet, the consumption of more probiotic food and avoidance of the antibiotic overuse might be desirable measures for the prevention and treatment of kidney stones. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=120 SRC="FIGDIR/small/512337v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@d3df85org.highwire.dtl.DTLVardef@1f7b3f5org.highwire.dtl.DTLVardef@147d861org.highwire.dtl.DTLVardef@1cf046e_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

FishSCT: a zebrafish-centric database for exploration and visualization of fish single-cell transcriptome

With the advancement of single-cell sequencing technology in recent years, an increasing number of researchers have turned their attention to the study of cell heterogeneity. In this study, we created a fish single-cell transcriptome database centered on zebrafish (Danio rerio). FishSCT currently contains single-cell transcriptomic data on zebrafish and 8 other fish species. We used a unified pipeline to analyze 129 datasets from 44 projects from SRA and GEO, resulting in 964/26,965 marker/potential marker information for 245 cell types, as well as expression profiles at single-cell resolution. There are 117 zebrafish datasets in total, covering 25 different types of tissues/organs at 36 different time points during the growth and development stages. This is currently the largest and most comprehensive online resource for zebrafish single-cell transcriptome data, as well as the only database dedicated to the collection of marker gene information of specific cell type and expression profiles at single-cell resolution for a variety of fish. A user-friendly web interface for information browsing, cell type identification, and expression profile visualization has been developed to meet the basic demand in related studies on fish transcriptome at the single-cell resolution.

bioinformatics↗

eIF3 mRNA selectivity profiling reveals eIF3k as a cancer-relevant regulator of ribosome content

eIF3, whose subunits are frequently overexpressed in cancer, regulates mRNA translation from initiation to termination, but mRNA-selective functions of individual subunits remain poorly defined. Using multi-omic profiling upon acute depletion of eIF3 subunits, we observed that while eIF3a, b, e, and f markedly differed in their impact on eIF3 holo-complex formation and translation, they were each required for cancer cell proliferation and tumor growth. Remarkably, eIF3k showed the opposite pattern with depletion promoting global translation, cell proliferation, tumor growth, and stress resistance through repressing the synthesis of ribosomal proteins, especially RPS15A. Whereas ectopic expression of RPS15A mimicked the anabolic effects of eIF3k depletion, disruption of eIF3 binding to the 5-UTR of RSP15A mRNA negated them. Supported by mathematical modeling, our data uncovers eIF3k-l as a mRNA-specific module which, through controlling RPS15A translation, serves as a rheostat of ribosome content to secure spare translational capacity that can be mobilized during stress.

cell biology↗

Evidence for a travel direction signal in humans that is independent of head direction

We often assume that travel direction is redundant with head direction, but from first principles these two factors provide differing spatial information. Although head direction has been found to be a fundamental component of human navigation, it is unclear how self-motion signals for travel direction contribute to forming a travel trajectory. Employing a novel motion adaptation paradigm from visual neuroscience designed to preclude a contribution of head direction, we found high-level aftereffects of perceived travel direction, indicating that travel direction is a fundamental component of human navigation. Interestingly, we discovered a higher frequency of reporting perceived travel toward the adapted direction compared to a no-adapt control - an aftereffect that runs contrary to low-level motion aftereffects. This travel aftereffect was maintained after controlling for possible response biases and approaching effects, and it scaled with adaptation duration. These findings demonstrate the first evidence of how a pure travel direction signal might be represented in humans, independent of head direction.

neuroscience↗

Gigaxonin is required for intermediate filament transport

Gigaxonin is an adaptor protein for E3 ubiquitin ligase substrates. It is necessary for ubiquitination and degradation of intermediate filament (IF) proteins. Giant axonal neuropathy is a pathological condition caused by mutations in the GAN gene that encodes gigaxonin. This condition is characterized by abnormal accumulation of IFs in both neuronal and non-neuronal cells; however, it is unclear what causes IF aggregation. In this work, we studied the dynamics of IFs using their subunits tagged with a photoconvertible protein mEOS 3.2. We have demonstrated that the loss of gigaxonin dramatically inhibited transport of IFs along microtubules by the microtubule motor kinesin-1. This inhibition was specific for IFs, as other kinesin-1 cargoes, with the exception of mitochondria, were transported normally. Another effect of gigaxonin loss was a more than 20-fold increase in the amount of soluble vimentin oligomers in the cytoplasm of gigaxonin knock-out cells. We speculate that these oligomers saturate a yet unidentified adapter that is required for kinesin-1 binding to IFs, which might inhibit IF transport along microtubules causing their abnormal accumulation.

cell biology↗

Engineering precise adenine base editor with infinitesimal rates of bystander mutations and off-target editing

Adenine base editors (ABEs) catalyze A-to-G transitions showing broad applications, but their bystander mutations and off-target editing effects raise the concerns of safety issues. Through structure-guided engineering, we found ABE8e with an N108Q mutation reduced both adenine and cytosine bystander editing, and introduction of an additional L145T mutation (ABE9), further refined the editing window to 1-2nt with eliminated cytosine editing. Importantly, ABE9 induced very minimal RNA and undetectable Cas9-independent DNA off-target effects, which mainly installed desired single A-to-G conversion in mouse and rat embryos to efficiently generate disease models. Moreover, ABE9 accurately edited A5 position of the protospacer sequence in pathogenic homopolymeric adenosine sites (up to 342.5-fold precision than ABE8e) and was further confirmed through a library of guide RNA-target sequence pairs. Due to the minimized editing window, ABE9 could further broaden the targeting scope for precise correction of pathogenic SNVs when fused to Cas9 variants with expanded PAM compatibility.

bioengineering↗

A scalable sparse neural network framework for rare cell type annotation of single-cell transcriptome data

Cell type annotation is critical to understand the cell population heterogeneity in the single-cell RNA sequencing (scRNA-seq) analysis. Due to their fast, precise, and user-friendly advantages, automatic annotation methods are gradually replacing traditional unsupervised clustering approaches in cell type identification practice. However, current supervised annotation tools are easily overfitting, thus favoring large cell populations but failing to learn the information of smaller populations. This drawback will significantly mislead biological analysis, especially when the rare cell types are important. Here, we present scBalance, an integrated sparse neural network framework that leverages the adaptive weight sampling and dropout techniques for the auto-annotation task. Using 20 scRNA-seq datasets with different scales and different imbalance degrees, we systematically validate the strong performance of scBalance for both intra-dataset and inter-dataset annotation tasks. Furthermore, we also demonstrate the scalability of scBalance on identifying rare cell types in million-level datasets by uncovering the immune landscape in bronchoalveolar cells. Up to now, scBalance is the first and only auto-annotation tool that expands scalability to 1.5 million cells dataset. In addition, scBalance also shows a fast and stable speed outperforming commonly used tools across all scales of datasets. We implemented scBalance in a user-friendly manner that can easily interact with Scanpy, which makes scBalance a superior tool in the increasingly important Python-based platform.

bioinformatics↗

Cell wall extensin arabinosylation is required for root directional response to salinity

Soil salinity is a major contributor to crop yield losses. To improve our understanding of root responses to salinity, we developed and exploit here a real-time salt-induced tilting assay (SITA). This method follows root growth upon both gravitropic and salt challenges, revealing that root bending upon tilting is modulated by salinity, but not by osmotic stress. Next, this salt-specific response was measured in 345 natural Arabidopsis accessions and we discovered a genetic locus, encoding for the cell-wall modifying enzyme EXTENSIN ARABINOSE DEFICIENT TRANSFERASE (ExAD), to be associated with root bending in salt. Extensins are a class of structural cell wall glycoproteins [hydroxyproline-rich glycoproteins (HRGPs)] which are post-translationally modified by O-glycosylation mostly in the form of hydroxyproline (Hyp)-arabinosylation. We show that salt induces ExAD-dependent Hyp-arabinosylation, influencing root bending responses and cell wall thickness. We report that roots of exad mutants, which lack extensin Hyp-Araf4 modifications, display increased root epidermal cell wall thickness and porosity and altered gravitropic root bending in salt, as well as a reduced salt avoidance response. Our results suggest that extensin modification via Hyp-arabinosylation represents a novel salt-specific cellular process that is required for the directional response of roots exposed to salinity.

plant biology↗

Dominant constraints on the evolution of rhythmic gene expression

Although the individual transcriptional regulators of the core circadian clock are distinct amongst different organisms, the autoregulatory feedback loops they form are conserved. This unified design principle explains how daily physiological activities oscillate across species. However, whether analogous design principles govern the gene expression output of circadian clocks is unknown. Herein, we performed a comparative analysis of rhythmic gene expression in eight diverse species and captured four common distribution patterns of cycling gene expression across these species. We hypothesized that maintenance of reduced energetic costs constrains the evolution of rhythmic gene expression. Our large-scale computational simulations support this hypothesis by showing that selection against high-energy expenditure completely regenerates all cycling gene patterns. Moreover, we find that the late- and early-phase peaks of rhythmic expression have been subjected to this type of selective pressure. Therefore, energetic costs have constricted the cycling transcriptome throughout evolutionary history.

cell biology↗

Innate and adaptive immune basis of mental health effect on Alzheimer's disease progression

Mental health has long been suspected to be highly associated with neurodegenerative disease, but it lacks experimental evidence to elaborate the link and immunological mechanism between them. In this work, we studied the progression of Alzheimers disease (AD) and its associated immune activity by using the transgenic mice under negative (depression) and positive (environmental enrichment, EE) mental health intervention. The tissue pathology, resident and peripheral immunity and behavioral characteristics were investigated. The transgenic mice undergoing depression treatment was featured with aggravated AD pathology, elevated activation of microglia in the brains, more abundance of Treg cells and cytotoxic T cells, and higher ratios of central memory T cells to effector memory T (TCM-to-TEM) cells in the peripheral blood and spleens. The EE treated mice were featured with alleviated AD pathology, reduced activation of microglia, less amounts of Treg and cytotoxic T cells and lower ratios of TCM-to-TEM cells. This study may provide strategies for immunity regulation and mental health intervention that benefit AD therapy. Significance statementMental health is suspected to regulate AD progression, but its validation in histology examination and the regulatory mechanism remains unclear. Here, we prove that both innate and adaptive immunity are playing important roles and mental health-immunity-AD progression forms a triad. More active microglia, Treg, and cytotoxic T cells, and higher TCM-to-TEM feature negative mental health and severer AD progress, and vice versa. The findings in adaptive immunity and the triad may inspire AD regulation.

animal behavior and cognition↗

The evolution of two transmissible cancers in Tasmanian devils

Tasmanian devils have spawned two transmissible cancer lineages, named devil facial tumour 1 (DFT1) and devil facial tumour 2 (DFT2). We investigated the genetic diversity and evolution of these clones by analysing 78 DFT1 and 41 DFT2 genomes relative to a newly assembled chromosome-level reference. Time-resolved phylogenetic trees reveal that DFT1 first emerged in 1986 (1982-1989), and DFT2 in 2011 (2009-2012). Subclone analysis documents transmission of heterogeneous cell populations. DFT2 has faster mutation rates than DFT1 across all variant classes, including substitutions, indels, rearrangements, transposable element insertions and copy number alterations, and we identify a hypermutated DFT1 lineage with defective DNA mismatch repair. Several loci show plausible evidence of positive selection in DFT1 or DFT2, including loss of chromosome Y and inactivation of MGA, but none are common to both cancers. This study illuminates the parallel long-term evolution of two transmissible cancers inhabiting a common niche in Tasmanian devils.

cancer biology↗

Reconstitution of the SARS-CoV-2 ribonucleosome provides insights into genomic RNA packaging and regulation by phosphorylation

The nucleocapsid (N) protein of coronaviruses is responsible for compaction of the [~]30-kb RNA genome in the [~]100-nm virion. Cryo-electron tomography suggests that each virion contains 35-40 viral ribonucleoprotein (vRNP) complexes, or ribonucleosomes, arrayed along the genome. There is, however, little mechanistic understanding of the vRNP complex. Here, we show that N protein, when combined with viral RNA fragments in vitro, forms cylindrical 15-nm particles similar to the vRNP structures observed within coronavirus virions. These vRNPs form in the presence of stem-loop-containing RNA and depend on regions of N protein that promote protein-RNA and protein-protein interactions. Phosphorylation of N protein in its disordered serine/arginine (SR) region weakens these interactions and disrupts vRNP assembly. We propose that unmodified N binds stem-loop-rich regions in genomic RNA to form compact vRNP complexes within the nucleocapsid, while phosphorylated N maintains uncompacted viral RNA to promote the proteins transcriptional function.

biochemistry↗

Novel tumorigenic FOXM1-PTAFR-PTAF axis revealed by multi-omic profiling in TP53/CDKN2A-double knockout human gastroesophageal junction organoid model

Inactivation of the tumor suppressor genes TP53 and CDKN2A occurs early during gastroesophageal junction (GEJ) tumorigenesis. However, due to a paucity of GEJ-specific disease models, cancer-promoting consequences of TP53 and CDKN2A inactivation at the GEJ have been incompletely characterized. Here we report the development of the first wild-type primary human GEJ organoid model, as well as a CRISPR-edited transformed GEJ organoid model. CRISPR/Cas9 engineering to inactivate TP53 and CDKN2A (TP53/CDKN2AKO) in GEJ organoids induced morphologic dysplasia as well as pro-neoplastic features in vitro and tumor formation in vivo. Notably, lipidomic profiling identified several Platelet-Activating Factors (PTAFs) among the most upregulated lipids in CRISPR-edited organoids; and importantly, PTAF/PTAFR abrogation by siRNA knockdown or a pharmacologic inhibitor (WEB2086) significantly blocked proliferation and other pro-neoplastic features of TP53/CDKN2AKO GEJ organoids in vitro and tumor formation in vivo. In addition, murine xenografts derived from Eso26, an established esophageal adenocarcinoma (EAC) cell line, were suppressed by WEB2086. Mechanistically, TP53/CDKN2A dual inactivation disrupted both the transcriptome and the DNA methylome, likely mediated by key transcription factors, particularly Forkhead Box M1 (FOXM1). Importantly, FOXM1 activated PTAFR transcription by binding to the PTAFR promoter, further amplifying the PTAF-PTAFR pathway. In summary, we established a robust model system for investigating early GEJ neoplastic events, identified crucial metabolic and epigenomic changes occurring during GEJ model tumorigenesis, and discovered a potential cancer-therapeutic strategy, while providing insights into pro-neoplastic mechanisms associated with TP53/CDKN2A inactivation in early GEJ neoplasia. One Sentence SummaryNovel tumorigenic FOXM1-PTAFR-PTAF axis revealed by multi-omic profiling in TP53/CDKN2A-double knockout human gastroesophageal junction organoid model. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=172 SRC="FIGDIR/small/491356v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@18dcb8dorg.highwire.dtl.DTLVardef@2ec0d6org.highwire.dtl.DTLVardef@17622b8org.highwire.dtl.DTLVardef@e184bc_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

The swan genome and transcriptome: its not all black and white

The Australian black swan (Cygnus atratus) is an iconic species with contrasting plumage to that of the closely related Northern Hemisphere white swans. The relative geographic isolation of the black swan may have resulted in a limited immune repertoire and increased susceptibility to infectious disease, notably infectious diseases from which Australia has been largely shielded. Indeed, unlike Mallard ducks and the mute swan (Cygnus olor), the black swan is extremely sensitive to severe highly pathogenic avian influenza (HPAI). Understanding this susceptibility has been impaired by the absence of any available swan genome and transcriptome information. Here, we generate the first chromosome-length annotated black and mute swan genomes annotated with transcriptome data, all using long-read based pipelines generated for vertebrate species. We used these genomes and transcriptomes, to show that unlike other wild waterfowl, black swans lack an expanded immune gene repertoire, lack a key viral pattern-recognition receptor in endothelial cells and mount a poorly controlled inflammatory response to HPAI. We also implicate genetic differences in SLC45A2 in the iconic plumage of the Australian black swan. Together, these data suggest that the immune system of the black swan is such that should any avian viral infection become established in its native habitat the survival of the black swan would be in significant peril.

genomics↗

Induction of neutralizing antibodies against SARS-CoV-2 variants by a multivalent mRNA-lipid nanoparticle vaccine encoding SARS-CoV-2/SARS-CoV Spike protein receptor-binding domains

To address the need for multivalent vaccines against Coronaviridae that can be rapidly developed and manufactured, we compared antibody responses against SARS-CoV, SARS-CoV-2, and several variants of concern in mice immunized with mRNA-lipid nanoparticle vaccines encoding homodimers or heterodimers of SARS-CoV/SARS-CoV-2 receptor-binding domains. All vaccine constructs induced robust anti-viral antibody responses, and the heterodimeric vaccine elicited an IgG response capable of cross-neutralizing SARS-CoV, SARS-CoV-2 Wuhan-Hu-1, B.1.351 (beta), and B.1.617.2 (delta) variants.

immunology↗