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Xue, Z.

Publications and source records attributed to Xue, Z..

At least 37 records · Page 2Linked to original sources

Evaluation of T Cell Receptor Construction Methods from scRNA-Seq Data

T cell receptors (TCRs) serve pivotal roles in the adaptive immune system by enabling recognition and response to pathogens and irregular cells. Various methods exist for TCR construction from single-cell RNA sequencing (scRNA-seq) datasets, each with its unique characteristics regarding accuracy, sensitivity, adaptability, usability, time, and memory consumption. Yet, a comprehensive understanding of their relative strengths and weaknesses for different applications remains elusive. In our research, we implemented a benchmark analysis utilizing experimental single-cell immune profiling datasets encompassing paired scRNA-seq as input and scTCR-seq datasets as ground truth reference from human and mouse. Additionally, we introduced a novel simulator, YASIM-scTCR (Yet Another Simulator for single-cell TCR), capable of generating scTCR-seq reads containing a diverse array of TCR- derived sequences under different sequencing depths and read lengths. Our results consistently showed that TRUST4 outperformed others across multiple datasets, while MiXCR and DeRR also demonstrated considerable accuracy. We also discovered that the sequencing depth inherently imposes a critical constraint on successful TCR construction from scRNA-seq data. In summary, we present a benchmark study to aid researchers in choosing the most appropriate methods for reconstructing TCR from scRNA-seq data.

bioinformatics↗

A novel downstream factor in willows replaces the ancestral sex determining gene

Sex chromosome turnover has occurred in many groups, and is mediated by the translocation or duplication of apical sex-determining genes, or the replacement of original sex determination genes by new ones. In dioecious plants, the former frequently occurs, while the latter is rarely reported. Here, we assembled four haplotype-resolved chromosome-level genomes from four lineages of the Salix polyclona complex, including three diploids (E, E-TS, and W1) and one autotetraploid (W2). Our analyses reveal that diploids have a ZW/ZZ system, while autotetraploid has a ZZZW/ZZZZ system on chromosome 15. The apical sex-determining genes of Salicaceae, ARR17-like duplicates on chromosomes 15 and 19, which can indirectly turn-on/off the expression of PISTILLATA (PI) gene and determine sex, appears to have lost the function of sex determination in the S. polyclona complex. We found a novel sex determining factor on the 15W of the complex, namely partial PI-like duplicates, which has taken over the function from the ARR17-like duplicates. In conclusion, a new dominant sex-determining gene was recruited in the S. polyclona complex, replacing the ancestral apical sex-determining ARR17-like duplicates. The newly identified partial PI-like duplicates exhibit a direct influence on the downstream intact PI-like duplications, providing valuable insights into the evolutionary trajectory of the top-down sex determination pathway.

evolutionary biology↗

eProbe: a capture probe design toolkit for genetic diversity reconstructions from ancient environmental DNA

Ancient environmental DNA (aeDNA) is now commonly used in paleoecology and evolutionary ecology, yet due to difficulties in gaining sufficient genome coverage on individual species from metagenome data, its genetic perspectives remain largely uninvestigated. Hybridization capture has proven as an effective approach for enriching the DNA of target species, thus increasing the genome coverage of sequencing data and enabling population and evolutionary genetics analysis. However, to date there is no tool available for designing capture probe sets tailored for aeDNA based population genetics. Here we present eProbe, an efficient, flexible and easy-to-use program toolkit that provides a complete workflow for capture probe design, assessment and validation. By benchmarking a probe set for foxtail millet, an annual grass, made by the eProbe workflow, we demonstrate a remarkable increase of capturing efficiency, with the target taxa recovery rate improved by 577-fold, and the genome coverage achieved by soil capture-sequencing data even higher than data directly shotgun sequenced from the plant tissues. Probes that underwent our filtering panels show notably higher efficiency. The capture sequencing data enabled accurate population and evolutionary genetic analysis, by effectively inferring the fine-scale genetic structures and patterns, as well as the genotypes on functional genes.

bioinformatics↗

Defining cellular determinants of resistance to PD-1 pathway blockade in non-small-cell lung cancer

Despite sustained clinical responses to immune-checkpoint blockade (ICB) therapies in non-small-cell lung cancer (NSCLC), the majority of patients derive no clinical benefits, and the cellular and molecular underpinnings of such resistance remain incompletely understood. To identify cell types that may influence immunotherapy responses, we first integrated newly generated and previously published single-cell RNA sequencing data from 110 treatment-naive patients with NSCLC. Among tumor-resident cell types, we identified MMP1+ cancer-associated fibroblasts (CAFs), which were inversely correlated with the level of tumor-reactive T cells--a key determinant of response to ICB. Further single-cell analysis for newly collected 21 tumor samples from NSCLC patients treated with anti-PD-1/PD-L1 agents revealed that MMP1+ fibroblasts were indeed enriched in treatment-refractory patients, and this observation was also validated in an independent dataset of bulk RNA sequencing from 344 NSCLC patients treated with PD-L1 agents. Examination of the spatial architecture showed that MMP1+ fibroblasts were located at the tumor-stroma boundary, forming a single-cell layer that encircled the cancer cell aggregates, and we hence defined MMP1+ fibroblasts as tumor-stroma boundary (tsb)CAFs. Such tsbCAFs likely promote resistance to ICB by functioning as a physical barrier that prevents tumor-reactive T cells from recognizing and killing cancer cells. Our study provides a new framework to identify cellular underpinnings of resistance to ICB and suggests new strategies to overcome ICB resistance. Highlights{lozenge} Identification and characterization of MMP1+ fibroblasts in lung cancer. {lozenge}Single-cell meta-analysis reveals cell populations impeding the accumulation of tumor-reactive T cells. {lozenge}MMP1+ fibroblasts correlate with the low infiltration of tumor-reactive T cells and the resistance to anti-PD-1/PD-L1 treatment. {lozenge}MMP1+ fibroblasts appear to form a space barrier between malignant and T cells.

immunology↗

Genome-wide mapping of native co-localized G4s and R-loops in living cells

The non-B DNA structures can act as dynamic functional genomic elements regulating gene expression. Among them, G4s and R-loops are two of the best studied. The interplay between R-loops and G4s are emerging in regulating DNA repair, replication and transcription. A comprehensive picture of native co-localized G4s and R-loops in living cells is currently lacking. Here, we describe the development of HepG4-seq and an optimized HBD-seq methods, which robustly capture native G4s and R-loops, respectively, in living cells. We successfully employed these methods to establish comprehensive maps of native co-localized G4s and R-loops in human HEK293 cells and mouse embryonic stem cells (mESCs). We discovered that co-localized G4s and R-loops are dynamically altered in a cell type-dependent manner and are largely localized at active promoters and enhancers of transcriptional active genes. We further demonstrated the helicase Dhx9 as a direct and major regulator that modulates the formation and resolution of co-localized G4s and R-loops. Depletion of Dhx9 impaired the self-renewal and differentiation capacities of mESCs by altering the transcription of co-localized G4s and R-loops - associated genes. Taken together, our work established that the endogenous co-localized G4s and R-loops are prevalently persisted in the regulatory regions of active genes and are involved in the transcriptional regulation of their linked genes, opening the door for exploring broader roles of co-localized G4s and R-loops in development and disease.

genomics↗

Parallel Evolution of Salinity Tolerance in Arabidopsis thaliana Accessions from Cape Verde Islands

Soil salinization poses a significant threat to crop production impacting one fifth of all cultivated land. The Cape Verde Islands are located 600 km from the coast of Africa and are characterized by high salinity soils and inland water sources. In this study we find that Arabidopsis thaliana plants native to these islands accumulate a metabolite that protects them from salt stress. We partially characterized this metabolite as glucuronyl-mannose. We find that the ability to produce glucuronyl-mannose evolved independently in two different islands from the same archipelago through mutations in the same gene, an alpha glycosidase protein that we named GH38cv. These cases of parallel evolution suggest positive selection towards the increase of salt tolerance with low fitness costs. Indeed, plants carrying derived alleles of GH38cv do not present growth defects or low defenses under normal conditions, but show better germination rates, longer roots and better hydric status than non-mutated plants when exposed to salt stress. These findings provide a knowledge-based method to develop salt resilient crops using natural mechanisms, which could be attractive both to conventional and organic agriculture.

plant biology↗

pH-Sensitive Nanodroplets for Controlled Delivery of Berberine Chloride

BackgroundThe development of nanocarriers with precise control over drug release is crucial for targeted therapy. This study focuses on the design and optimization of pH-sensitive gelatin/perfluorohexane (PFH) nanodroplets loaded with berberine chloride, a model drug relevant to traditional Chinese medicine. Subjects and MethodsNanodroplets were prepared using an emulsion technique, with optimization of parameters including homogenization rate, polymer concentration, surfactant, drug, and perfluorocarbon conte nt. ResultsThe optimized formulation resulted in nanodroplets with a mean particle size of 281.7 nm and a drug encapsulation efficiency of 66.8 {+/-} 1.7%. Characterization studies confirmed successful encapsulation and pH-responsive behavior. Ultrasound stimulation significantly enhanced drug release, with 150 kHz frequency proving more effective than 1 MHz. Stability studies demonstrated prolonged stability over one month at 4{degrees}C. Following 10 minutes of ultrasound irradiation, the nanodroplets exhibited 89.4% cumulative drug release. ConclusionsIn conclusion, these pH-sensitive nanodroplets show potential for delivering berberine chloride in a controlled manner, connecting traditional Chinese medicine with contemporary drug delivery methods.

biophysics↗

Battery-Free Optoelectronic Patch for Photodynamic and Light Therapies in Treating Bacteria-Infected Wounds

Light therapy is an effective approach for the treatment of a variety of challenging dermatological conditions. In contrast to existing methods involving high doses and large areas of illumination, alternative strategies based on wearable designs that utilize a low light dose over an extended period provide a precise and convenient treatment. In this study, we present a battery-free, skin-integrated optoelectronic patch that incorporates a coil-powered circuit, an array of microscale violet and red light emitting diodes (LEDs), and polymer microneedles (MNs) loaded with 5-aminolevulinic acid (5-ALA). This polymer MNs, based on the biodegradable composite materials of polyvinyl alcohol (PVA) and hyaluronic acid (HA), serves as light waveguides for optical access and a medium for drug release into deeper skin layers. Unlike conventional clinical photomedical appliances with a rigid and fixed light source, this flexible design allows for a conformable light source that can be applied directly to the skin. In animal models with bacterial-infected wounds, the experimental group with the combination treatment of metronomic photodynamic and light therapies reduced 2.48 log10 CFU mL-1 in bactericidal level compared to the control group, indicating an effective anti-infective response. Furthermore, post-treatment analysis revealed the activation of proregenerative genes in monocyte and macrophage cell populations, suggesting enhanced tissue regeneration, neovascularization, and dermal recovery. Overall, this optoelectronic patch design broadens the scope for targeting deep skin lesions, and provides an alternative with the functionality of standard clinical light therapy methods.

bioengineering↗

Exploratory study of pulsed electric field ablation on atherosclerotic plaque in a rabbit model

New understanding of the pathogenesis of atherosclerotic diseases has led to the emergence of new therapeutic approaches. We explored the potential therapeutic effects of pulsed field potential ablation (PFA), a non-thermal ablation technique with high tissue selectivity, on atherosclerotic plaques. Carotid arteries of 30 high-fat rabbits were dilated with a balloon to obtain atherosclerotic plaques. PFA was administered on the carotid atherosclerotic plaques with 1000V/cm, 2000V/cm, and 1000V/cm ablation followed by rapamycin infusion. There were no visible changes in blood vessels after acute ablation, but apoptosis and polarity of cells were observed in atherosclerotic plaques. At 7 and 30 days after ablation, the density of lipid deposition in the plaque was significantly reduced, and multiple layers of new arranged anterograde smooth muscle cells appeared, replacing the original atherosclerotic plaque. The residual atherosclerotic structure is sandwiched between the new smooth muscle layer and the original smooth muscle layer, which makes vascular wall thicker and makes vascular wall elasticity increased. Rapamycin delays the vascular remodeling process. Conclusion: PFA ablation can reduce lipid deposition in atherosclerotic plaques, cause vascular remodeling, and enhance vascular elasticity. We believe that it may be a potential method for the treatment of atherosclerotic plaques.

biophysics↗

Sex determination system turnovers play important roles in the willows speciation

Almost all species in the genus Salix (willow) are dioecious, but some have male and some female heterogamety, and the chromosomal location of the sex-linked regions (termed SDSs) differs between different species. We first analyzed the SDSs of two species, Salix cardiophylla and S. interior, whose positions in the Salix phylogeny make them important species for understanding a sex chromosome turnover that has been detected in their relatives, and that changed the system from male to female heterogamety. We show that both species have male heterogamety, with XY-linked regions on chromosome 15 (termed a 15XY system). The sex-linked regions occupy 21.3% and 22.8% of the entire reference chromosome, respectively. By constructing phylogenetic trees of species with known SDSs, we determined the phylogenetic positions of all the species. Reconstruction of SDSs revealed that 15XY system is likely the ancestral of willows. Finally, we tested for both current and ancestral gene flow between different species with the same or different sex-determining systems, as the sex chromosomes can play important roles in reproductive isolation between species. We inferred lower gene flow between species with XY on chromosome 7 (7XY) and ZW on chromosome 15 (15ZW) systems, compared with gene flow either between species with XY on chromosome 15 (15XY) and 15ZW systems or between species with 7XY and 15XY systems. We argue that, although sex chromosomes turnovers in willows may not create complete reproductive barriers, gene flow may be reduced between species with different SDSs.

evolutionary biology↗

bamSliceR: cross-cohort variant and allelic bias analysis for rare variants and rare diseases

The NCI Genomic Data Commons (GDC) provides controlled access to sequencing data from thousands of subjects, enabling large-scale study of impactful genetic alterations such as simple and complex germline and structural variants. However, efficient analysis requires significant computational resources and expertise, especially when recalling variants from raw sequence reads. We thus developed bamSliceR, an R/Bioconductor package that builds upon the GenomicDataCommons package to extract aligned sequence reads from cross-GDC meta-cohorts, followed by targeted analysis of variants and effects (including transcript-aware variant annotation from transcriptome-aligned GDC RNA data). Here we demonstrate population-scale genomic & transcriptomic analyses with minimal compute burden via bamSliceR, identifying recurrent, clinically relevant sequence and structural variants in the TARGET AML and BEAT-AML cohorts. We then validate results in the (non-GDC) Leucegene cohort, demonstrating how the bamSliceR pipeline can be seamlessly applied to replicate findings in non-GDC cohorts. These variants directly yield clinically impactful and biologically testable hypotheses for mechanistic investigation. bamSliceR has been submitted to the Bioconductor project, where it is presently under review, and is available on GitHub at https://github.com/trichelab/bamSliceR.

bioinformatics↗

Comprehensive Assessment of Isoform Detection Methods for Third-Generation Sequencing Data

The advancement of Third-Generation Sequencing (TGS) techniques has significantly increased the length of sequencing to several kilobases, thereby facilitating the identification of alternative splicing (AS) events and isoform expressions. Recently, numerous computational methods for isoform detection using long-read sequencing data have been developed. However, there is lack of prior comparative studies that systemically evaluates the performance of these software tools, implemented with different algorithms, under various simulations that encompass potential influencing factors. In this study, we conducted a benchmarking analysis of eleven methods implemented in eight computational tools capable of identifying isoform structures from TGS RNA sequencing data. We evaluated their performances using simulated data, which represented diverse sequencing platforms generated by an in-house simulator, as well as experimental data. Our comprehensive results demonstrate the guided mode of StringTie2 and Bambu achieved the best performance in sensitivity and precision, respectively. This study provides valuable guidance for future research on AS analysis and the ongoing improvement of tools for isoform detection using TGS data.

bioinformatics↗

DeepNeuropePred: a robust and universal tool to predict cleavage sites from neuropeptide precursors by protein language model

Neuropeptides play critical roles in many biological processes such as growth, learning, memory, metabolism, and neuronal differentiation. A few approaches have been reported for predicting neuropeptides that are cleaved from precursor protein sequences. However, these models for cleavage site prediction of precursors were developed using a limited number of neuropeptide precursor datasets and simple precursors representation models. In addition, a universal method for predicting neuropeptide cleavage sites that can be applied to all species is still lacking. In this paper, we proposed a novel deep learning method called DeepNeuropePred, using a combination of pretrained language model and Convolutional Neural Networks for feature extraction and predicting the neuropeptide cleavage sites from precursors. To demonstrate the models effectiveness and robustness, we evaluated the performance of DeepNeuropePred and four models from the NeuroPred server in the independent dataset and our model achieved the highest AUC score (0.916), which are 6.9%, 7.8%, 8.8%, and 10.9% higher than Mammalian (0.857), insects (0.850), Mollusc (0.842) and Motif (0.826), respectively. For the convenience of researchers, we provide an easy-to-install GitHub package (https://github.com/ISYSLAB-HUST/DeepNeuropePred) and a web server (http://isyslab.info/NeuroPepV2/deepNeuropePred.jsp). Key PointsO_LIDeepNeuropePred uses a deep learning algorithm based on protein language model to accurately predict neuropeptide cleavage sites from neuropeptide precursors. C_LIO_LIIndependent test experiments show that DeepNeuropePred achieves significantly better performance than existing methods. C_LIO_LIDeepNeuropePred could capture meaningful patterns between neuro-peptide and non-neuropeptide cleavage sites. C_LIO_LIWe further provide an easy-to-install GitHub package and a web server. C_LI

bioinformatics↗

Disease associated human TCR characterization by deep-learning framework TCR-DeepInsight

T cell function is defined by both T cell receptors (TCR) and T cell gene expression (GEX). Although single-cell technology enables the simultaneous capture of TCR and GEX information, the lack of a reference atlas and computational tools hinders our ability to uncover the fundamental TCR usage rules and to efficiently characterize disease-associated TCRs (dTCR). Here, through the collection of million-scale single-cell GEX-TCR reference atlas comprising 20 diverse disease conditions, we revealed the intrinsic features of TCR-MHC (Major Histocompatibility Complex) restriction in CD4/CD8 lineages. We observed the higher coherence for TCR/{beta} chains in memory T cells, and detected widely-existing public TCR/{beta} pairs across individuals. Building upon the reference atlas, we introduced TCR- DeepInsight, a deep-learning framework featuring a disease specificity scoring system that enables the characterization of dTCR clusters with similar GEX-TCR. Our study provides a valuable tool for researchers to analyze single-cell GEX-TCR data and identify dTCRs comprehensively and robustly.

bioinformatics↗

Multiplexed Sequential Imaging in Living Cells with Orthogonal Fluorogenic RNA Aptamer/Dye Pairs

Single-cell detection of multiple target analytes is an important goal in cell biology. However, due to the spectral overlap of common fluorophores, multiplexed fluorescence imaging beyond two-to-three targets inside living cells remains a technical challenge. Herein, we introduce a multiplexed imaging strategy that enables live-cell target detection via sequential rounds of imaging-and-stripping process, which is named as "sequential Fluorogenic RNA Imaging-Enabled Sensor" (seqFRIES). In seqFRIES, multiple orthogonal fluorogenic RNA aptamers are genetically encoded inside cells, and then the corresponding cell membrane permeable dye molecules are added, imaged, and rapidly removed in consecutive detection cycles. As a proof-of-concept, we have identified in this study five in vitro orthogonal fluorogenic RNA aptamer/dye pairs (>10-fold higher fluorescence signals), four of which can be used for highly orthogonal and multiplexed imaging in living bacterial and mammalian cells. After further optimizing the cellular fluorescence activation and deactivation kinetics of these RNA/dye pairs, the whole four-color semi-quantitative seqFRIES process can now be completed in [~]20 min. Meanwhile, seqFRIES-mediated simultaneous detection of two critical signaling molecules, guanosine tetraphosphate and cyclic diguanylate, was also achieved within individual living cells. We expect our validation of this new seqFRIES concept here will facilitate the further development and potential broad usage of these orthogonal fluorogenic RNA/dye pairs for highly multiplexed and dynamic cellular imaging and cell biology studies.

bioengineering↗

Targeted RNA Condensation in Living Cells via Genetically Encodable Triplet Repeat Tags

Living systems contain various functional membraneless organelles that can segregate selective proteins and RNAs via liquid-liquid phase separation. Inspired by nature, many synthetic compartments have been engineered in vitro and in living cells, mostly focused on protein-scaffolded systems. Herein, we introduce a nature-inspired genetically encoded RNA tag to program cellular condensate formations and recruit non-phase-transition target RNAs to achieve functional modulation. In our system, different lengths of CAG-repeat tags were tested as the self-assembled scaffold to drive multivalent condensate formation. Various selective target messenger RNAs and noncoding RNAs can be compartmentalized into these condensates. With the help of fluorogenic RNA aptamers, we have systematically studied the formation dynamics, spatial distributions, sizes, and densities of these cellular RNA condensates. The regulation functions of these CAG-repeat tags on the cellular RNA localization, lifetime, RNA-protein interactions, and gene expression have also been investigated. Considering the importance of RNA condensation in both health and disease conditions, these genetically encodable modular and self-assembled tags can be potentially widely used for chemical biology and synthetic biology studies.

bioengineering↗

DPHL v2: An updated and comprehensive DIA pan-human assay library for quantifying more than 14,000 proteins.

A comprehensive pan-human spectral library is critical for biomarker discovery using mass spectrometry (MS)-based proteomics. DPHL v1, a previous pan-human library built from 1096 data-dependent acquisition (DDA) MS data of 16 human tissue types, allows quantifying 10,943 proteins. However, a major limitation of DPHL v1 is the lack of semi-tryptic peptides and protein isoforms, which are abundant in clinical specimens. Here, we generated DPHL v2 from 1608 DDA-MS data acquired using Orbitrap mass spectrometers. The data included 586 DDA-MS newly acquired from 17 tissue types, while 1022 files were derived from DPHL v1. DPHL v2 thus comprises data from 24 sample types, including several cancer types (lung, breast, kidney, and prostate cancer, among others). We generated four variants of DPHL v2 to include semi-tryptic peptides and protein isoforms. DPHL v2 was then applied to a publicly available colorectal cancer dataset with 286 DIA-MS files. The numbers of identified and significantly dysregulated proteins increased by at least 21.7% and 14.2%, respectively, compared with DPHL v1. Our findings show that the increased human proteome coverage of DPHL v2 provides larger pools of potential protein biomarkers.

bioinformatics↗

MSdb: an integrated expression atlas of human musculoskeletal system

We introduce MSdb (https://www.msdb.org.cn), a database for visualization and integrated analysis of next-generation sequencing data from human musculoskeletal system, along with manually curated patient phenotype data. Systematic categorizing, standardized processing and freely accessible knowledge enables the reuse of public data. MSdb provides various types of analysis, including sample-level browsing of metadata information, gene/miRNA expression, and single-cell RNA-seq dataset. In addition, MSdb also allows integrated analysis for cross-samples and cross-omics analysis, including customized differentially-expressed gene/microRNA analysis, microRNA-gene network, scRNA-seq cross-sample/disease integration, and gene regulatory network analysis.

bioinformatics↗