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Hu, P.

Publications and source records attributed to Hu, P..

At least 55 records · Page 3Linked to original sources

KMCP: accurate metagenomic profiling of both prokaryotic and viral populations by pseudo-mapping

MotivationThe growing number of microbial reference genomes enables the improvement of metagenomic profiling accuracy but also imposes greater requirements on the indexing efficiency, database size, and runtime of taxonomic profilers. Additionally, most profilers focus mainly on bacterial, archaeal, and fungal populations, while less attention is paid to viral communities. ResultsWe present KMCP, a novel k-mer-based metagenomic profiling tool that utilizes genome coverage information by splitting the reference genomes into chunks and then stores k-mers in a modified and optimized COBS index for fast alignment-free sequence searching. KMCP combines k-mer similarity and genome coverage information to reduce the false positive rate of k-mer-based taxonomic classification and profiling methods. Benchmarking results based on simulated and real data demonstrate that KMCP, despite a longer running time than all other methods, not only allows the accurate taxonomic profiling of prokaryotic and viral populations but also provides confident pathogen detection in clinical samples of low depth. Availability and ImplementationThe software is open-source under the MIT license and available at https://github.com/shenwei356/kmcp.

bioinformatics↗

Structural-functional connectivity mapping of the insular cortex system: A combined data-driven and meta-analytic topic mapping approach

In this study, we examined structural and functional profiles of the insular cortex and mapped associations with well-described functional networks (FNs) throughout the brain using diffusion tensor imaging (DTI) and resting-state functional connectivity (RSFC) data. We used a data-driven method to independently estimate the structural-functional connectivity of the insular cortex. Data were obtained from the Human Connectome Project comprising 108 adult participants. Overall, we observed moderate to high associations between the structural and functional mapping scores of three different insular subregions: the posterior insula (associated with the sensorimotor network: RSFC, DTI = 50% and 72%, respectively), dorsal anterior insula (associated with ventral attention: RSFC, DTI = 83% and 83%, respectively), and ventral anterior insula (associated with the frontoparietal: RSFC, DTI = 42% and 89%, respectively). Further analyses utilized meta-analytic decoding maps to demonstrate specific cognitive and affective as well as gene expression profiles of the three subregions reflecting the core properties of the insular cortex. In summary, given the central role of the insular in the human brain, our results revealing correspondence between DTI and RSFC mappings provide a complementary approach and insight for clinical researchers to identify dysfunctional brain organization in various neurological disorders associated with insular pathology.

neuroscience↗

A multi-tiered map of EMT defines major transition points and identifies vulnerabilities

Epithelial to mesenchymal transition (EMT) is a complex cellular program proceeding through a hybrid E/M state linked to cancer-associated stemness, migration and chemoresistance. Deeper molecular understanding of this dynamic physiological landscape is needed to define events which regulate the transition and entry into and exit from the E/M state. Here, we quantified >60,000 molecules across ten time points and twelve omic layers in human mammary epithelial cells undergoing TGF{beta}-induced EMT. Deep proteomic profiles of whole cells, nuclei, extracellular vesicles, secretome, membrane and phosphoproteome defined state-specific signatures and major transition points. Parallel metabolomics showed metabolic reprogramming preceded changes in other layers, while single-cell RNA sequencing identified transcription factors controlling entry into E/M. Covariance analysis exposed unexpected discordance between the molecular layers. Integrative causal modeling revealed co-dependencies governing entry into E/M that were verified experimentally using combinatorial inhibition. Overall, this dataset provides an unprecedented resource on TGF{beta} signaling, EMT and cancer.

systems biology↗

The First High-Quality Reference Genome of Sika Deer Provides Insights for High-Tannin Adaptation

Sika deer are known to prefer oak leaves, which are rich in tannins and toxic to most mammals; however, the genetic mechanisms underlying their unique ability to adapt to living in the jungle are still unclear. In identifying the mechanism responsible for the tolerance of a highly toxic diet, we have made a major advancement in the elucidation of the genomics of sika deer. We generated the first high-quality, chromosome-level genome assembly of sika deer and measured the correlation between tannin intake and RNA expression in 15 tissues through 180 experiments. Comparative genome analyses showed that the UGT and CYP gene families are functionally involved in the adaptation of sika deer to high-tannin food, especially the expansion of UGT genes in a subfamily. The first chromosome-level assembly and genetic characterization of the tolerance toa highly toxic diet suggest that the sika deer genome will serve as an essential resource for understanding evolutionary events and tannin adaptation. Our study provides a paradigm of comparative expressive genomics that can be applied to the study of unique biological features in non-model animals.

genomics↗

Depleting Hypothalamic Somatostatinergic Neurons Recapitulates Diabetic Phenotypes in Brain, Bone Marrow, Adipose, and Retina

Hypothalamic inflammation and sympathetic nervous system hyperactivity are hallmark features of metabolic syndrome and type 2 diabetes. Hypothalamic inflammation may aggravate metabolic and immunologic pathologies due to extensive sympathetic activation of peripheral tissues. Loss of somatostatinergic (SST) neurons may contribute to enhanced hypothalamic inflammation. The present data show that leptin receptor deficient (db/db) mice exhibit reduced hypothalamic somatostatinergic cells, particularly in the periventricular nucleus. We model this finding, using adeno-associated virus (AAV) delivery of diphtheria toxin (DTA) driven by an SST-cre system to deplete these cells in SSTcre/gfp mice (SST-DTA). SST-DTA mice exhibit enhanced hypothalamic c-fos expression and brain inflammation as demonstrated by microglial and astrocytic activation. Bone marrow from SST-DTA mice undergoes skewed hematopoiesis, generating excess granulocyte-monocyte precursors and increased pro-inflammatory (CCR2hi) monocytes. Visceral adipose tissue from DTA-treated animals was resistant to catecholamine induced lipolysis. Finally, SST-DTA mice exhibited a "diabetic retinopathy like" phenotype: reduced visual function by optokinetic response and electroretinogram, as well as increased percentages of retinal monocytes. Importantly, hyperglycemia was not observed in SST-DTA mice. Thus, the isolated reduction in hypothalamic somatostatinergic neurons was able to recapitulate several hallmark features of type 2 diabetes in disease relevant tissues.

neuroscience↗

Quantitative single cell 5hmC sequencing reveals non-canonical gene regulation by non-CG hydroxymethylation

Oxidative modification of 5-methylcytosine (5mC) generates 5-hydroxymethylcytosine (5hmC), a DNA modification that exhibits unique epigenetic regulatory functions and impacts diverse biological processes. However, standard single-nucleus/cell bisulfite sequencing methods cannot resolve the base ambiguity between 5mC and 5hmC to accurately measure cell-type specific epigenomic patterns and gene regulatory functions of 5hmC or true 5mC. Here, we develop single-nucleus 5hmC sequencing (snhmC-seq) for quantitative and unbiased 5hmC profiling in single cells by harnessing differential deaminase activity of APOBEC3A towards 5mC and chemically protected 5hmC. We used snhmC-seq to profile single nuclei from cryopreserved mouse brain samples to reveal epigenetic heterogeneity of 5hmC at single-cell resolution and uncovered a non-canonical gene regulatory role of genic 5hmC in non-CG context.

genomics↗

Ameliorating Emotional Attention through Modulation of Neural Oscillations with Transcranial Alternating Current Stimulation

BackgroundNumerous clinical reports suggest that psychopathy like schizophrenia, anxiety and depressive disorder is accompanied by early attentional abnormalities in emotional information processing. In the past decade, the efficacy of transcranial alternating current stimulation (tACS) in changing emotional functioning has been repeatedly observed and has demonstrated a causal relationship between endogenous oscillations and emotional processing. However, tACS effects on emotional attention have not yet been tested. MethodsA total of 53 healthy participants were randomized to 2 groups, and they were subjected to active or sham tACS at individual alpha frequency (IAF) in the bilaterally dorsolateral prefrontal cortex (dlPFC). Participants and received this treatment for 20 min durations daily for 7 consecutive days. On days 1 and 7, electroencephalogram (EEG) recording of 8 minute resting with eyes open and closed. Responses to a facial emotion identification task were also recorded to measure alpha changes and event-related potential (ERP) alterations. ResultsOn day 7 after tACS, the active group showed a more clear elevation in alpha power at rest, especially in open state around stimulation area, compared to the sham group. ERPs revealed a significant larger P200 amplitude after active stimulation (p < 0.05), indicating attentional improvement in facial emotion processing. Additionally, a notable positive correlation (p < 0.05) between alpha power and P200 amplitude was found, providing an electrophysiological interpretation regarding the role of tACS in emotional attention modulation. In addition, the IAF-tACS showed an obvious advantage in alpha entrainment compared to an additional 10 Hz-tACS. ConclusionsThese results support a seminal outcome for the effect of IAF-tACS on emotional attention modulation, demonstrating a feasible and individual-specific therapy for neuropsychiatric disorders related to emotion processing, especially regarding oscillatory disturbances.

bioengineering↗

De novo germline mutation in the Dual Specificity Phosphatase 10 gene accelerates autoimmune diabetes in Non-Obese Diabetic (NOD) mice

Here we report the isolation by selective breeding of two sublines of Non-Obese Diabetic (NOD) mice exhibiting a significant difference in the incidence of autoimmune type 1 diabetes (T1D). Whole genome sequencing of the NOD/NckH (high T1D incidence) and NOD/NckL (low T1D incidence) revealed the presence of a limited number of variants specific to each subline. Treating the age of T1D onset as a quantitative trait and using automated meiotic mapping (AMM), enhanced susceptibility in the NOD/NckH subline was unambiguously attributed to a recessive allele of Dusp10 which encodes a dual specificity phosphatase. The causative effect of the mutation was verified with a high level of confidence by targeting Dusp10 with CRISPR/Cas9 in NOD/NckL mice: in these animals a higher incidence of diabetes was observed. Expression of wild-type Dusp10 correlated with higher levels of surface PD-L1 in the islets of NOD/NckL mice.

immunology↗

Stress-induced epigenetic regulation of transcription in neocortical excitatory neurons drives depression-like behavior

Prolonged stress exposure is a major risk factor for the development of depression and comorbid anxiety. Efforts to understand how recurrent stress induces behavioral maladaptation have largely concentrated on the neuronal synapse with limited understanding of the underlying epigenetic mechanisms. Here, we performed complementary bulk nuclei- and single-nucleus transcriptome profiling and mapped fine-scale chromatin architecture in mice subjected to chronic unpredictable stress (CUS) to identify the cell type-specific epigenetic alterations that drive complex behavior. We find that neocortical excitatory neurons are particularly vulnerable to chronic stress and acquire signatures of transcription and chromatin configuration that denote reduced neuronal activity and expression of Yin Yang 1 (YY1). Selective ablation of YY1 in excitatory neurons of the prefrontal cortex (PFC) enhances stress sensitivity in mice, inducing depressive- and anxiety-related behaviors and deregulating the expression of stress-associated genes following an abbreviated stress exposure. Notably, we find that loss of YY1 in PFC excitatory neurons provokes more maladaptive behaviors in stressed females than males. These findings demonstrate how chronic stress provokes maladaptive behavior by epigenetically shaping excitatory neurons in the PFC, identifying a novel molecular target for therapeutic treatment of stress-related mood and anxiety disorders.

neuroscience↗

Visualizing dendritic characteristics of corticotropin-releasing hormone neurons at single-cell resolution in the whole mouse brain

Corticotropin-releasing hormone (CRH) is an important neuromodulator with wide distribution in the brain. Here, we screened the CRH-IRES-Cre;Ai32 mouse line to reveal the morphologies of individual CRH neurons throughout the mouse brain by using fluorescence micro-optical sectioning tomography (fMOST) system. Diverse dendritic morphologies and projection fibers were found in various brain regions. Reconstructions showed hypothalamic CRH neurons had the smallest somatic volumes and simplest dendritic branches, and CRH neurons in several regions shared a bipolar morphology. Further investigations in the medial prefrontal cortex unveiled somatic depth-dependent morphologies that exhibited three types of connections and CRH neurons in the anterior parvicellular area of hypothalamus had fewer and smaller Herring bodies whereas in the periventricular area had more and larger Herring bodies that were present within fibers projecting to the third ventricle. Our findings provide the most comprehensive intact morphologies of CRH neurons throughout the mouse brain that is currently available.

neuroscience↗

Loss of FSTL1-expressing adipocyte progenitors drives the age-related involution of brown adipose tissue

In humans, brown adipose tissue (BAT) undergoes progressive involution or atrophy with increasing age, as manifested by decreased prevalence and mass, transformation to white adipose tissue (WAT), and reduction in thermogenic activity. This involution process cannot be fully recapitulated in rodent models and thus underlying cellular mechanisms are poorly understood. Here, we show that the interscapular BAT (iBAT) in rabbits involutes rapidly in early life, similarly to that in humans. The transcriptomic remodeling and identity switch of mature adipocytes are accompanied with the loss of brown adipogenic competence of their precursor cells. Through single-cell RNA sequencing, we surveyed the heterogenous populations of mesenchymal cells within the stromal vascular fraction of rabbit and human iBAT. An analogous FSTL1high population of brown adipocyte progenitors exists in both species while gradually disappear during iBAT involution in rabbits. In mice, FSTL1 is highly expressed by adipocyte progenitors in iBAT and genetic deletion of FSTL1 causes defective WNT signaling and iBAT atrophy in neonates. Our results underscore the BAT-intrinsic contribution from FSTL1high progenitors to age-related tissue involution and point to a potential therapeutic approach for obesity and its comorbidities. HIGHLIGHTSO_LIRabbit BAT irreversibly transforms to WAT before puberty. C_LIO_LIiBAT adipocyte progenitors reprogram transcriptome and lose brown adipogenic ability. C_LIO_LIComparable FSTL1high brown adipocyte progenitors exist in rabbit and human iBAT. C_LIO_LILoss of FSTL1 in brown adipocyte progenitors causes iBAT atrophy in mice. C_LI

physiology↗

Dynamics of the cell-free DNA methylome of metastatic castration resistant prostate cancer during androgen-targeting treatment

AimWe examined methylation changes in cell-free DNA (cfDNA) in metastatic castration resistant prostate cancer (mCRPC) during treatment. Materials and MethodsGenome-wide methylation analysis of sequentially collected cfDNA samples derived from mCRPC patients undergoing androgen-targeting therapy was performed. ResultsAlterations in methylation states previously implicated in prostate cancer progression were observed and patients that maintained methylation changes throughout therapy tended to have a longer time to clinical progression (TTP). Importantly, we also report that markers associated with a highly aggressive form of the disease, Neuroendocrine-CRPC, were associated with a faster TTP. ConclusionOur findings highlight the potential of monitoring cfDNA methylome during therapy in mCRPC, which may serve as predictive markers of response to androgen-targeting agents.

cancer biology↗

Massively parallel, time-resolved single-cell RNA sequencing with scNT-Seq

Single-cell RNA sequencing offers snapshots of whole transcriptomes but obscures the temporal dynamics of RNA biogenesis and decay. Here we present single-cell new transcript tagging sequencing (scNT-Seq), a method for massively parallel analysis of newly-transcribed and pre-existing RNAs from the same cell. This droplet microfluidics-based method enables high-throughput chemical conversion on barcoded beads, efficiently marking metabolically labeled newly-transcribed RNAs with T-to-C substitutions. By simultaneously measuring new and old transcriptomes, scNT-Seq reveals neuronal subtype-specific gene regulatory networks and time-resolved RNA trajectories in response to brief (minutes) versus sustained (hours) neuronal activation. Integrating scNT-Seq with genetic perturbation reveals that DNA methylcytosine dioxygenases may inhibit stepwise transition from pluripotent embryonic stem cell state to intermediate and totipotent two-cell-embryo-like (2C-like) states by promoting global RNA biogenesis. Furthermore, pulse-chase scNT-Seq enables transcriptome-wide measurements of RNA stability in rare 2C-like cells. Time-resolved single-cell transcriptomic analysis thus opens new lines of inquiry regarding cell-type-specific RNA regulatory mechanisms.

genomics↗

Elucidation of the determinant for orchestration of solo unisexual cycle in an important human fungal pathogen

In fungi, the sex-determination program universally directs sexual development and syngamy (the fusion of gametes) that underlies pre-meiotic diploidization. However, the contribution of sex-determination to syngamy-independent sexual cycle, which requires autopolyploidization as an alternative approach to elevate ploidy before meiosis, remains unclear in fungi and other eukaryotes. The human fungal pathogen Cryptococcus neoformans, as a model organism for studying fungal sexual reproduction, can undergo syngamy-dependent bisexual and syngamy-independent solo unisexual reproduction, in which endoreplication is considered to enable pre-meiotic self-diploidization. Here, by characterizing a mutant lacking all the core sex-determination factors, we show that sex-determination plays a central role in bisexual syngamy but is not strictly required for unisexual development and self-diploidization. This implies an unknown circuit, rather than the sex-determination program, for specifically coordinating Cryptococcus unisexual cycle. We reveal that syngamy and self-diploidization are both governed by the Qsp1-directed paracrine system via two regulatory branches, Vea2 and Cqs2. Vea2 directs bisexual syngamy through the sex-determination program; conversely, Cqs2 is dispensable for bisexual syngamy but activates unisexual endoreplication. Through functional profiling of 41 transcription factors documented to regulate Cryptococcus sexual development, we reveal that only Cqs2 can drive and integrate all unisexual phases and ensure the production of meiospore progenies. Furthermore, ChIP-seq analysis together with genetic evaluation indicate that Cqs2 induces unisexual self-diploidization through its direct control of PUM1, whose expression is sufficient to drive autopolyploidization. Therefore, Cqs2 serves as the critical determinant that orchestrates Cryptococcus multistage unisexual cycle that does not strictly require the sexual-determination program.

microbiology↗

Dosage effect of multiple genes accounts for multisystem disorder of myotonic dystrophy type 1

Multisystem manifestations in myotonic dystrophy type 1 (DM1) may be due to dosage reduction in multiple genes induced by aberrant expansion of CTG repeats in DMPK, including Dmpk and its neighboring genes (Six5 or Dmwd) and downstream Mbnl1. However, the direct evidences are lack. Here, we develop a new strategy to generate mice carrying multigene mutations in one step by injection of haploid embryonic stem cells with mutant Dmpk, Six5 and Mbnl1 into oocytes. The triple heterozygous mutant mice exhibit adult-onset DM1 phenotypes. With the additional mutation in Dmwd, quadruple heterozygous mutant mice recapitulate many major manifestations in congenital DM1. Moreover, muscle stem cells in both models display reduced stemness. Our results suggest that the complex symptoms of DM1 result from the reduced gene dosage of multiple genes.

genetics↗

Unusual metabolism and hypervariation in the genome of a Gracilibacteria (BD1-5) from an oil degrading community

The Candidate Phyla Radiation (CPR) comprises a large monophyletic group of bacterial lineages known almost exclusively based on genomes obtained using cultivation-independent methods. Within the CPR, Gracilibacteria (BD1-5) are particularly poorly understood due to undersampling and the inherent fragmented nature of available genomes. Here, we report the first closed, curated genome of a Gracilibacteria from an enrichment experiment inoculated from the Gulf of Mexico and designed to investigate hydrocarbon degradation. The gracilibacterium rose in abundance after the community switched to dominance by Colwellia. Notably, we predict that this gracilibacterium completely lacks glycolysis, the pentose phosphate and Entner-Doudoroff pathways. It appears to acquire pyruvate, acetyl-CoA and oxaloacetate via degradation of externally derived citrate, malate and amino acids and may use compound interconversion and oxidoreductases to generate and recycle reductive power. The initial genome assembly was fragmented in an unusual gene that is hypervariable within a repeat region. Such extreme local variation is rare, but characteristic of genes that confer traits under pressure to diversify within a population. Notably, the four major repeated 9-mer nucleotide sequences all generate a proline-threonine-aspartic acid (PTD) repeat. The genome of an abundant Colwellia psychrerythraea population has a large extracellular protein that also contains the repeated PTD motif. Although we do not know the host for the BD1-5 cell, the high relative abundance of the C. psychrerythraea population and the shared surface protein repeat may indicate an association between these bacteria.\n\nImportanceCPR bacteria are generally predicted to be symbionts due to their extensive biosynthetic deficits. Although monophyletic, they are not monolithic in terms of their lifestyles. The organism described here appears to have evolved an unusual metabolic platform not reliant on glucose or pentose sugars. Its biology appears to be centered around bacterial host-derived compounds and/or cell detritus. Amino acids likely provide building blocks for nucleic acids, peptidoglycan and protein synthesis. We resolved an unusual repeat region that would be invisible without genome curation. The nucleotide sequence is apparently under strong diversifying selection but the amino acid sequence is under stabilizing selection. The amino acid repeat also occurs in a surface protein of a coexisting bacterium, suggesting co-location and possibly interdependence.

microbiology↗

Corticotropin-Releasing Hormone Signaling in the Oval Bed Nucleus of the Stria Terminalis Mediates Chronic Stress-Induced Negative Valence Behaviors Associated with Anxiety

The bed nucleus of stria terminalis (BNST) is a forebrain region highly sensitive to stress that expresses corticotropin-releasing hormone (CRH) neuropeptide at high levels and regulates negative valence behaviors associated with anxiety. However, how chronic stress modulates CRH signaling and neuronal activity in BNST remains unknown. We subjected C57BL6/J mice to a 6-week chronic variable mild stress (CVMS) paradigm and investigated the effects on behavior, BNST cellular neurophysiology, and BNST CRH signaling. We also utilized pharmacological infusions and optogenetics to decipher and mimic the effects of CVMS on BNST cellular neurophysiology and behavior. CVMS elevated plasma corticosterone levels, induced negative valence behaviors associated with anxiety, diminished M-currents (voltage-gated K+ currents that stabilize membrane potential and regulate neuronal excitability), and increased mEPSC amplitude in ovBNST. Additionally, the number of c-fos+, CRH+, and CRH activator pituitary adenylate cyclase-activating polypeptide (PACAP)+ cells were increased while CRH inhibitor striatal-enriched protein tyrosine phosphatase (STEP)+ cells were decreased in ovBNST. These expression data were confirmed with qPCR. CVMS also activated PKA in BNST and the electrophysiological and behavioral effects of CVMS were reversed by ovBNST infusion of the PKA-selective antagonist H89. Moreover, optogenetic activation of ovBNST directly induced negative valence behaviors associated with anxiety, mimicking the effects of CVMS. CVMS mediates effects on negative valence behaviors associated with anxiety by activating CRH signaling components and cellular excitability in ovBNST Our findings decipher an important CRH-associated stress molecular signature in BNST and advance our understanding of the neural circuitry underlying stress-induced disorders.

neuroscience↗

Analysis of small RNA silencing in Zymoseptoria tritici - wheat interactions

Cross-kingdom small RNA (sRNA) silencing has recently emerged as a mechanism facilitating fungal colonization and disease development. Here we characterized RNAi pathways in Zymoseptoria tritici, a major fungal pathogen of wheat, and assessed their contribution to pathogenesis. Computational analysis of fungal sRNA and host mRNA sequencing datasets was used to define the global sRNA populations in Z. tritici and predict their mRNA targets in wheat. 389 in planta-induced sRNA loci were identified. sRNAs generated from some of these loci were predicted to target wheat mRNAs including those potentially involved in pathogen defense. However, molecular approaches failed to validate targeting of selected wheat mRNAs by fungal sRNAs. Mutant strains of Z. tritici carrying deletions of genes encoding key components of RNAi such as Dicer-like (DCL) and Argounate (AGO) proteins were generated, and virulence bioassays suggested that these are dispensable for full infection of wheat. Nonetheless, our results did suggest the existence of non-canonical DCL-independent pathway(s) for sRNA biogenesis in Z. tritici. dsRNA targeting essential fungal genes applied in vitro or generated from an RNA virus vector in planta in a procedure known as HIGS (Host-Induced Gene Silencing) was ineffective in preventing Z. tritici growth or disease. We also demonstrated that Z. tritici is incapable of dsRNA uptake. Collectively, our data suggest that RNAi approaches for gene function analyses in this fungal species and potentially also as a control measure may not be as effective as has been demonstrated for some other plant pathogenic fungi.

plant biology↗