Biology subjects

Wang, N.

Publications and source records attributed to Wang, N..

At least 181 records · Page 10Linked to original sources

bioRxiv2023

Genome-wide Perturbation Analysis Screening System for Exosomes-Related Genes Based on the CRISPR/Cas9 Platform

As reported previously, exosomes have significant impacts on the physiological and pathological state in vivo. Exosomes have been extensively studied as a drug delivery carrier and some exosomes drugs have been undergoing clinical research. The mechanisms of exosome production, transport, and secretion remain to be studied in depth. Thus, here, we developed a novel CRISPR-UMI-based gene screening system, with which we can reveal the exosomes biogenesis, transport, and uptake mechanisms on a genome-wide scale. This system consists of two parts: one is a gene knockout component; the other part is a unique molecular identifiers (UMI) labeling component that can label the exosomes produced by the knockout cells, in which each sgRNA corresponds to a specific UMI. In this way, by detecting the UMI loaded in the exosomes, we can trace the knockout gene. In this study, we first verified the function of each component using plasmids and lentiviruses respectively. Next, we simulated the infection of cells with lentiviral libraries using a single lentivirus to validate the functionality of the screening system. Finally, we constructed a CRISPR-UMI-based library targeting 15 genes (genes with clear effects on exosomes biogenesis) to further validate the reliability of the screening system. The development of this screening system is of indispensable importance for the in-depth study of the mechanisms of exosome production and secretion, as well as for the improvement of exosomes production and the advancement of exosomes industrialization.

bioengineering↗

bioRxiv2023

Replication stress in activated human NK cells induces sensitivity to apoptosis

Natural killer cells are innate immune effectors that kill virally infected or malignant cells. Natural killer cell deficiency (NKD) occurs when NK cell development or function are impaired, and individuals with NKD are susceptible to severe and recurrent viral infections. Several gene deficiencies result in NKD, including variants in MCM4, GINS1, MCM10 and GINS4, which are components of the CDC45-MCM-GINS (CMG) helicase. The CMG helicase unwinds DNA during replication and is expressed in any actively proliferating cell. NK cells are more strongly impacted by mutational deficiencies in helicase proteins than other lymphocytes, though the mechanisms underlying this susceptibility are not completely understood. NK cells from individuals with NKD as a result of helicase deficiency have increased DNA damage, cell cycle arrest, and replication stress. Here, we induced replication stress in activated mature NK cells or T cells by chemical methods, using aphidicolin, and through shRNA knockdown of MCM10 in an NK cell line. We found that the CD56bright subset of NK cells accumulates more DNA damage and replication stress during activation than CD56dim NK cells or activated T cells. Aphidicolin treatment increases apoptosis of CD56bright NK cells through increased pan-caspase expression and decreases perforin expression in surviving cells. This effect is modeled by shRNA mediated knockdown of MCM10, thus linking decreased helicase protein expression to replication stress and impaired NK cell function. These findings show that sensitivity to replication stress affects human NK cell survival and function and can contribute to NK cell deficiency.

immunology↗

bioRxiv2023

A hybrid machine learning and regression method for cell type deconvolution of spatial barcoding-based transcriptomic data

Spatial barcoding-based transcriptomic (ST) data require cell type deconvolution for cellular-level downstream analysis. Here we present SDePER, a hybrid machine learning and regression method, to deconvolve ST data using reference single-cell RNA sequencing (scRNA-seq) data. SDePER uses a machine learning approach to remove the systematic difference between ST and scRNA-seq data (platform effects) explicitly and efficiently to ensure the linear relationship between ST data and cell type-specific expression profile. It also considers sparsity of cell types per capture spot and across-spots spatial correlation in cell type compositions. Based on the estimated cell type proportions, SDePER imputes cell type compositions and gene expression at unmeasured locations in a tissue map with enhanced resolution. Applications to coarse-grained simulated data and four real datasets showed that SDePER achieved more accurate and robust results than existing methods, suggesting the importance of considering platform effects, sparsity and spatial correlation in cell type deconvolution.

bioinformatics↗

bioRxiv2023

Chromosome-Level Genome Assembly of Navel orange cv. Gannanzao (Citrus sinensis Osbeck cv. Gannanzao)

Navel orange cv. Gannanzao is a variant of the navel orange cv. Newhall (C. sinensis Osbeck cv. Newhall) that exhibits an earlier maturation, making it commercially valuable. However, the underlying mechanism underneath its early maturation remains unknown. To address this question, we conducted genome sequencing and de novo assembly of navel orange cv. Gannanzao. The assembled genome sequence is 334.57 Mb in length with a GC content of 31.48%. It comprises 318 contigs (N50 = 3.23 Mb) and 187 scaffolds (N50 = 31.86 Mb). The BUSCO test demonstrates 94.6% completeness. The annotation revealed 23,037 gene models, 164.95 Mb of repetitive sequences, and 2,554 ncRNA. Comparative analysis identified 323 fruit ripening-related genes in navel orange cv. Gannanzao genome, while navel orange cv. Newhall genome contained 345 such genes. These genes were organized into 320 orthologous gene families, with 30.3% of them exhibiting differences in gene copy numbers between the two genomes. Additionally, we identified 15 fruit ripening-related genes that have undergone adaptive evolution, suggesting their potential role in advancing fruit maturation in navel orange cv. Gannanzao. Whole genome sequencing and annotation of navel orange cv. Gannanzao provides a valuable resource to unravel the early maturation mechanism of citrus and enriches the genomic resources for citrus research.

genomics↗

bioRxiv2023

Chromosome-Level Genome Assembly of Navel orange cv. Gannanzao (Citrus sinensis Osbeck cv. Gannanzao)

genomics↗

bioRxiv2023

Parvalbumin and somatostatin: biomarkers for two parallel tectothalamic pathways in the auditory midbrain

The inferior colliculus (IC) represents a crucial relay station in the auditory pathway, located in the midbrains tectum and primarily projecting to the thalamus. Despite the identification of distinct cell types based on various biomarkers in the IC, their specific contributions to the organization of auditory tectothalamic pathways have remained poorly understood. In this study, we demonstrate that IC neurons expressing parvalbumin (ICPV+) or somatostatin (ICSOM+) represent major, non-overlapping cell types throughout the three IC subdivisions. Strikingly, regardless of their location within the IC, these neurons predominantly project to the primary and secondary auditory thalamic nuclei, respectively. Retrograde tracing data specific to cell types indicate that ICPV+ neurons primarily receive auditory inputs, whereas ICSOM+ neurons integrate polymodal inputs that hold behavioral significance. Furthermore, ICPV+ neurons exhibit significant heterogeneity in both intrinsic electrophysiological properties and presynaptic terminal size compared to ICSOM+ neurons. Notably, approximately one quarter of ICPV+ neurons are inhibitory neurons, whereas all ICSOM+ neurons are excitatory neurons. Collectively, our findings suggest that parvalbumin and somatostatin expression in the IC can serve as biomarkers for two functionally distinct, parallel tectothalamic pathways. This discovery challenges the conventional IC subdivision-based definition of tectothalamic pathways and calls for a reassessment of their functional roles.

neuroscience↗

bioRxiv2023

ASB3 expression aggravates inflammatory bowel disease by targeting TRAF6 protein stability and affecting the intestinal microbiota

E3 ubiquitin ligase (E3) plays a vital role in regulating inflammatory responses by mediating ubiquitination. Previous studies have shown that ankyrin repeat and SOCS box-containing protein 3 (ASB3) is involved in immunomodulatory functions associated with cancer. However, the impact of ASB3 on the dynamic interplay of microbiota and inflammatory responses in inflammatory bowel disease (IBD) is unclear. Here we systematically identify the E3 ligase ASB3 as a facilitative regulator in the development and progression of IBD. ASB3-/- mice are resistant to DSS-induced colitis. I{kappa}B phosphorylation levels and production of proinflammatory factors IL-1{beta}, IL-6, and TNF- were reduced in colonic tissues of ASB3-/- mice compared to WT mice. This colitis-resistant phenotype was suppressed after coprophagic microbial transfer and reversed after combined antibiotic clearance of the microbiota. Mechanistically, ASB3 specifically catalyzes K48-linked polyubiquitination of TRAF6 in IECs. In contrast, in ASB3-deficient organoids, the integrity of the TRAF6 protein is shielded, consequently decelerating the onset of intestinal inflammation. Taken together, Our findings demonstrates that ASB3 is associated with dysregulation of the colitis microbiota and promotes proinflammatory factors production by disrupting the TRAF6 stability. Strategies to limit the protein level of ASB3 in intestinal epithelial cells may help in the treatment of colitis.

immunology↗

bioRxiv2023

Atypical Biological Motion Perception in Children with Attention Deficit Hyperactivity Disorder: Dissociating the Roles of Local Motion and Global Configuration Processing

Perceiving biological motion (BM) is crucial for human survival and social interaction. Many studies have reported impaired BM perception in autism spectrum disorder, which is characterised by deficits in social interaction. Children with attention deficit hyperactivity disorder (ADHD) often exhibit similar difficulties in social interaction. However, few studies have investigated BM perception in children with ADHD. Here, we compared differences in the ability to process local kinematic and global configurational cues, two fundamental abilities of BM perception, between typically developing and ADHD children. We further investigated the relationship between BM perception and social interaction skills measured using the Social Responsiveness Scale and examined the contributions of latent factors (e.g., sex, age, attention, and intelligence) to BM perception. The results revealed that children with ADHD exhibited atypical BM perception. Local and global BM processing showed distinct features. Local BM processing ability was related to social interaction skills, whereas global BM processing ability significantly improved with age. Critically, general BM perception (i.e., both local and global BM processing) may be affected by sustained attentional ability in children with ADHD. This relationship was primarily mediated by reasoning intelligence. These findings elucidate atypical BM perception in ADHD and the latent factors related to BM perception. Moreover, this study provides new evidence that BM perception is a hallmark of social cognition and advances our understanding of the potential roles of local and global processing in BM perception and social cognitive disorders.

neuroscience↗

bioRxiv2023

Polyamine transport inhibition and cisplatin synergistically enhance tumor control through oxidative stress in murine head and neck cancer models

BackgroundSurgery and/or platinum-based chemoradiation remain standard of care for patients with head and neck squamous cell carcinoma (HNSCC). While these therapies are effective in a subset of patients, a substantial proportion experience recurrence or treatment resistance. As cisplatin mediates cytotoxicity through oxidative stress while polyamines play a role in redox regulation, we posited that combining cisplatin with polyamine transport inhibitor, AMXT-1501, would increase oxidative stress and tumor cell death in HNSCC cells. MethodsCell proliferation was measured in syngeneic mouse HNSCC cell lines treated with cisplatin {+/-} AMXT-1501. Synergy was determined by administering cisplatin and AMXT-1501 at a ratio of 1:10 to cancer cells in vitro. Cancer cells were transferred onto mouse flanks to test the efficacy of treatments in vivo. Reactive oxygen species (ROS) were measured. Cellular apoptosis was measured with flow cytometry using Annexin V/PI staining. High-performance liquid chromatography (HPLC) was used to quantify polyamines in cell lines. Cell viability and ROS were measured in the presence of exogenous cationic amino acids. ResultsThe combination of cisplatin and AMXT-1501 synergize in vitro on HNSCC cell lines. In vivo combination treatment resulted in tumor growth inhibition greater than either treatment individually. The combination treatment increased ROS production and induced apoptotic cell death. HPLC revealed the synergistic mechanism was independent of intracellular polyamine levels. Supplementation of cationic amino acids partially rescued cancer cell viability and reduced ROS. ConclusionAMXT-1501 enhances the cytotoxic effects of cisplatin in vitro and in vivo in aggressive HNSCC cell lines through a polyamine-independent mechanism.

cancer biology↗

bioRxiv2023

The protein interactome of the citrus Huanglongbing pathogen Candidatus Liberibacter asiaticus

Candidatus Liberibacter asiaticus (CLas) is the causal agent of the devastating citrus Huanglongbing (HLB) disease. Our understanding of the pathogenicity mechanism and biology of CLas remain limited because CLas has not been cultured in artificial media. CLas encodes 1136 proteins of which 415 have unknown functions. Since genetic studies of CLas genes with unknown functions are impossible, we utilized genome-wide protein-protein interactions (PPIs) yeast-two-hybrid (Y2H) assays to help solve the mystery. PPIs are fundamental to all cellular processes and machinery and instrumental in investigating uncharacterized proteins and inferring biological pathways. In total, 916 bait and 936 prey proteins were included in the three-phase screening, which identified 4245 interactions. The false positive rate of the Y2H assay was estimated to be 3.1%. Pull-down assays confirmed the robustness of our Y2H. The average interactions per node for CLas Y2H interactome were approximately 15.6, significantly higher than free-living bacteria, indicating genome reduction has led to a multi-function of proteins. PPIs provide clues for functions of 371 uncharacterized proteins of CLas. Forty HUB node proteins were identified which might play critical roles in CLas, including a quinone oxidoreductase and LysR that are known to protect bacteria against oxidative stress. This explains why CLas survives well in the phloem even though it triggers immune-mediated disease, systemic and chronic production of reactive oxygen species, and phloem cell death. This PPI database facilitates the investigation of CLas cellular biochemistry and physiology, functions of uncharacterized proteins, and pathogenicity mechanisms of the pathogen.

systems biology↗

bioRxiv2023

Lysosomal mitochondrial interaction promotes tumor growth in squamous cell carcinoma of the head and neck

Tumor growth and proliferation are regulated by numerous mechanisms. Communication between intracellular organelles has recently been shown to regulate cellular proliferation and fitness. The way lysosomes and mitochondria communicate with each other (lysosomal/mitochondrial interaction) is emerging as a major determinant of tumor proliferation and growth. About 30% of squamous carcinomas (including squamous cell carcinoma of the head and neck, SCCHN) overexpress TMEM16A, a calcium-activated chloride channel, which promotes cellular growth and negatively correlates with patient survival. TMEM16A has recently been shown to drive lysosomal biogenesis, but its impact on mitochondrial function is unclear. Here, we show that (1) patients with high TMEM16A SCCHN display increased mitochondrial content specifically complex I; (2) In vitro and in vivo models uniquely depend on mitochondrial complex I activity for growth and survival; (3) {beta}-catenin/NRF2 signaling is a critical linchpin that drives mitochondrial biogenesis, and (4) mitochondrial complex I and lysosomal function are codependent for proliferation. Taken together, our data demonstrate that LMI drives tumor proliferation and facilitates a functional interaction between lysosomes and mitochondria. Therefore, inhibition of LMI may serve as a therapeutic strategy for patients with SCCHN.

cancer biology↗

bioRxiv2023

Incomplete Reprogramming of DNA Replication Timing in Induced Pluripotent Stem Cells

Induced pluripotent stem cells (iPSC) are a widely used cell system and a foundation for cell therapy. Differences in gene expression, DNA methylation, and chromatin conformation, which have the potential to affect differentiation capacity, have been identified between iPSCs and embryonic stem cells (ESCs). Less is known about whether DNA replication timing - a process linked to both genome regulation and genome stability - is efficiently reprogrammed to the embryonic state. To answer this, we profiled and compared genome-wide replication timing between ESCs, iPSCs, and cells reprogrammed by somatic cell nuclear transfer (NT-ESCs). While NT-ESCs replicated their DNA in a manner indistinguishable from ESCs, a subset of iPSCs exhibit delayed replication at heterochromatic regions containing genes downregulated in iPSC with incompletely reprogrammed DNA methylation. DNA replication delays were not the result of gene expression and DNA methylation aberrations and persisted after differentiating cells to neuronal precursors. Thus, DNA replication timing can be resistant to reprogramming and lead to undesirable phenotypes in iPSCs, establishing it as an important genomic feature to consider when evaluating iPSC lines.

genetics↗

bioRxiv2023

CytoSIP: An annotated structural atlas for interactions involving cytokine or cytokine receptor

Cytokines primarily interact with specific cytokine receptors on the cell surface as essential signal transduction pathways in many physiological and pathological processes. Therapeutic agents targeting cytokine-cytokine receptor (CK-CKR) interactions lead to the disruption in cellular signaling function and have been demonstrated effective in the treatment of many diseases including tumors. However, a lack of universal and quick access to annotated structural surface regions on CK/CKR has limited the progress of a structure-driven approach to the development of targeted macromolecular drugs and precision medicine therapeutics. Herein we develop CytoSIP (Single nucleotide polymorphisms (SNPs), Interface, and Phenotype), a rich internet application based on a database of atomic interactions around hotspots in experimentally determined CK/CKR structural complexes. The content of the CytoSIP database includes the following key features: (1) SNPs on CK/CKR; (2) interactions involving CK/CKR at the domain level, including CK/CKR interfaces, oligomeric interfaces, epitopes, or other drug targeting surfaces; and (3) diseases and phenotypes associated with CK/CKR or SNPs. The database introduces a unique tri-level SIP data model to link genetic variants (atomic level) to disease phenotypes (organism level) using protein structure (complexes) as an underlying framework (molecule level). Moreover, CytoSIP implements screening criteria and tools to allow customized selection of relevant subset of CK/CKR for the study of interest. This reduces the time and resources needed to interrogate large datasets and allows rapid screening of cytokines and cytokine receptor proteins interfaces for hotspots targeted drug design and any other specific cellular signaling/function mechanisms and their correlation to pathologies. The CytoSIP framework crafted herein bridges CK/CKR genotype with phenotype, facilitating not only the panoramic investigation of the context-dependent crosstalk between CK/CKR but also the development of targeted therapeutic agents. CytoSIP portal website is publicly accessible at https://CytoSIP.biocloud.top.

immunology↗

bioRxiv2023

Seasonal Variation in Bacterial Community Structures of Mangrove Sediments

Climate change globally and sea level rise affect the mangrove ecosystem. The high diversity and temporal heterogeneity of the mangrove ecosystem will lead to a high diversity of sediment bacterial community structure and function. However, seasonal variations and potential assembly mechanisms of sediment bacterial communities in mangrove ecosystems remain to be discovered. We collected rhizosphere sediments and bulk sediments from Kandelia obovata and Aegiceras corniculatum at three locations covering Dongzhai Harbour in spring, summer, autumn, and winter, and sequenced 16S rRNAs. The results indicated that the alpha and beta diversity of bacterial communities in mangrove sediments differed significantly between seasons, and the bacterial communities in rhizosphere sediments had smaller seasonal changes and were more stable than those in bulk sediment bacterial communities. The seasonal changes in carbon, nitrogen content, and pH were the main influencing factors. The stochastic process dominated the assembly of bacterial communities in mangrove sediments. The assembly of bacterial communities varies between seasons. We found that the proportion of dispersal limitation was significantly negatively correlated with the carbon and nitrogen content in the sediment. Compared with bulk components, the dispersal limitation of bacterial communities in rhizosphere sediments accounted for a lower proportion of community construction, which might be caused by higher carbon and nitrogen content conditions in rhizosphere sediments. We found that beta diversity based on Bray-Curtis distance was significantly positively correlated with dispersal limitation, which explained why the beta diversity of bacterial communities in rhizosphere sediments was significantly lower than that of bulk components. This study increases the understanding of the responses of mangrove bacterial communities to seasonal change and may be beneficial for the protection of mangrove ecosystems in the face of climate change.

ecology↗

bioRxiv2023

StocSum: stochastic summary statistics for whole genome sequencing studies

Genomic summary statistics, usually defined as single-variant test results from genome-wide association studies, have been widely used to advance the genetics field in a wide range of applications. Applications that involve multiple genetic variants also require their correlations or linkage disequilibrium (LD) information, often obtained from an external reference panel. In practice, it is usually difficult to find suitable external reference panels that represent the LD structure for underrepresented and admixed populations, or rare genetic variants from whole genome sequencing (WGS) studies, limiting the scope of applications for genomic summary statistics. Here we introduce StocSum, a novel reference-panel-free statistical framework for generating, managing, and analyzing stochastic summary statistics using random vectors. We develop various downstream applications using StocSum including single-variant tests, conditional association tests, gene-environment interaction tests, variant set tests, as well as meta-analysis and LD score regression tools. We demonstrate the accuracy and computational efficiency of StocSum using two cohorts from the Trans-Omics for Precision Medicine Program. StocSum will facilitate sharing and utilization of genomic summary statistics from WGS studies, especially for underrepresented and admixed populations.

genetics↗

bioRxiv2023

The novel roles of bovine milk-derived exosomes on skin anti-aging

Exosomes are small vesicles released from cells and present in various mammal biological fluids, such as bovine milk, which worked for skin care for many years besides dairy. In addition, Exosomes were regarded as a vehicle for intercellular communication. Therefore, we aimed to investigate the novel roles of bovine milk-derived exosomes (MK-Exo) on human skin anti-aging. Purified MK-Exo can be directly uptake by the keratinocytes and fibroblast in vitro and upregulate the expression of the natural factors related to skin moisturizing, including Filaggrin (FLG), Aquaporin 3 (AQP3), CD44 in the keratinocytes and hyaluronidase (HAS2) in the fibroblast, and MK-Exo promoted the cell migration of the fibroblast, while rescue its expression of type I collagen (Col I), type III collagen (Col III) after ultraviolet radiation. Furthermore, the phototoxicity test, photoallergy test, repeated skin irritation test, skin allergy test, and patch test confirm the safety of MK-Exo on the skin. Finally, the roles of MK-Exo in preserving moisture and anti-wrinkle were also identified in humans. Then, MK-Exo was smeared on the facial skin of 31 female volunteers twice a day for 28 days, and the functions were evaluated following the safety assessment in vivo. These studies reveal the novel roles of bovine milk-derived exosomes in human skin aging, which opens a new way of skin care.

cell biology↗

bioRxiv2023

Social Behavior Atlas: A computational framework for tracking and mapping 3D close interactions of free-moving animals

The study of social behaviors in animals is essential for understanding their survival and reproductive strategies. However, accurately tracking and analyzing the social interactions of free-moving animals has remained a challenge. Existing multi-animal pose estimation techniques suffer from drawbacks such as the need for extensive manual annotation and difficulty in discriminating between similar-looking animals in close social interactions. In this paper, we present the Social Behavior Atlas (SBeA), a novel computational framework that solves these challenges by employing a deep learning-based video instance segmentation model, 3D pose reconstruction, and unsupervised dynamic behavioral clustering. SBeA framework also involves a multi-camera setup to prevent occlusion, and a novel approach to identify individual animals in close social interactions. We demonstrate the effectiveness of SBeA in tracking and mapping the 3D close interactions of free-moving animals using the example of genetic mutant mice, birds, and dogs. Our results show that SBeA is capable of identifying subtle social interaction abnormalities, and the models and frameworks developed can be applied to a wide range of animal species. SBeA is a powerful tool for researchers in the fields of neuroscience and ecology to study animal social behaviors with a high degree of accuracy and reliability.

neuroscience↗

bioRxiv2023

Efficient transgene-free genome editing in plants in the T0 generation based on a co-editing strategy

Transgene-free genome editing of plants in the T0 generation is highly desirable but challenging, especially in perennials and vegetatively propagated plants. Here, we investigated the co-editing strategy for generating transgene-free, gene-edited plants via Agrobacterium-mediated transient expression of cytosine base editor (CBE)/gRNA-Cas12a/crRNA-GFP in planta. Specifically, CBE/gRNA was used to base edit the ALS gene to confer resistance to herbicide chlorsulfuron as a selection marker, which has no negative effects on plant phenotypes; Cas12a/crRNA was used for editing genes(s) of interest; GFP was used for selecting transgene-free transformants. Using this approach, transgene-free genome-edited plants were efficiently generated for various genes (either individual or multiplex) in tomato, tobacco, potato, and citrus in the T0 generation. The biallelic/homozygous transgene-free mutation rates for target genes among herbicide-resistant transformants ranged from 8% to 50%. Whole genome sequencing further confirmed transgene-free and absence of off-target mutations in the edited plants. The co-editing strategy is efficient for generating transgene-free, genome-edited plants in the T0 generation, thus being a potent tool for plant genetic improvement.

plant biology↗