Biology subjects

Du, H.

Publications and source records attributed to Du, H..

At least 73 records · Page 4Linked to original sources

bioRxiv2023

Chromatin and Gene Regulatory Dynamics of Optic Nerve Invasion in Retinoblastoma at Single-Cell Resolution

Retinoblastoma (RB), the most aggressive pediatric intraocular malignancy, urgently requires mechanistic insights to overcome limitations of current clinical interventions. Through integrated single-cell multi-omics analysis, we constructed a comprehensive epigenetic-transcriptomic atlas of photoreceptor subpopulations in RB. Pseudotemporal trajectory analysis revealed the differentiation cascade from retinal progenitor cells (RPCs) to malignant cone-like tumor cells (Cone-T), orchestrated by dynamic regulation of tumor suppressors (FEZ1) and oncogenic drivers (CITED2) within the MAPK pathway. Notably, we identified three photoreceptor subtype-specific transcription factors (EBF1, SOX15, NFIL3) exhibiting concordant overexpression and chromatin accessibility. Cell-cell communication analysis uncovered PPIA-BSG ligand-receptor interactions potentially driving tumor progression, while drug screening prioritized nine therapeutic candidates targeting transitional proliferative photoreceptors (P-p). Our findings establish a mechanistic framework for photoreceptor transformation and provide actionable targets for precision therapies.

cancer biology↗

bioRxiv2023

Progranulin inhibits phospholipase sPLA2-IIA to control neuroinflammation

Withdrawal StatementThe authors have withdrawn this manuscript because more work is needed to fully define the role of sPLA2-IIA. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

neuroscience↗

bioRxiv2023

SEQUENCE VS. STRUCTURE: DELVING DEEP INTO DATA DRIVEN PROTEIN FUNCTION PREDICTION

AO_SCPLOWBSTRACTC_SCPLOWPredicting protein function is a longstanding challenge that has significant scientific implications. The success of amino acid sequence-based learning methods depends on the relationship between sequence, structure, and function. However, recent advances in AlphaFold have led to highly accurate protein structure data becoming more readily available, prompting a fundamental question: given sufficient experimental and predicted structures, should we use structure-based learning methods instead of sequence-based learning methods for predicting protein function, given the intuition that a proteins structure has a closer relationship to its function than its amino acid sequence? To answer this question, we explore several key factors that affect function prediction accuracy. Firstly, we learn protein representations using state-of-the-art graph neural networks (GNNs) and compare graph construction(GC) methods at the residue and atomic levels. Secondly, we investigate whether protein structures generated by AlphaFold are as effective as experimental structures for function prediction when protein graphs are used as input. Finally, we compare the accuracy of sequence-only, structure-only, and sequence-structure fusion-based learning methods for predicting protein function. Additionally, we make several observations, provide useful tips, and share code and datasets to encourage further research and enhance reproducibility.

bioinformatics↗

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

CircRNA-disease inference using deep ensemble model based on triple association

Accumulating evidence indicates more and more circular RNAs (i.e. circRNAs) have played a vital role in regulating gene expression and are related to diseases through different biological procedures. Predicting circRNA-disease associations helps to conjecture possible disease related circRNA and facilitate human disease diagnosis and downstream treatment. Nevertheless, little effort was made to uncover the interaction between various diseases and circRNAs. In our work, human circRNA-disease association network is first generated using known miRNA-circRNA interactions and disease related miRNA (microRNA) information. Then we further integrated this information to compute similarity scores between human diseases and circRNAs. Here, we proposed one deep ensemble model called DeepInteract, which first used two stacked auto-encoders to explore hidden features utilizing similarity information, and adopted a 3-layer neuron network to predict the final association. Our method is capable of capturing more complex non-linear features comparing to other approaches. Our results indicate the proposed method is superior to other previous competitors. Many prediction results have been validated by some biological experiments using our model.

bioinformatics↗

bioRxiv2022

rcsB enhances drug resistance of Klebsiella pneumoniae ATCC43816 by regulating the formation of its capsule

ObjectiveTo analyze the composition and drug resistance characteristics of clinical isolates from a tertiary general hospital of Lianyungang in 2021, and to explore the possible regulatory mechanism of drug resistance of Klebsiella pneumoniae. MethodsThe clinical samples submitted in 2021 were collected for bacterial culture, identification and drug sensitivity test, and the distribution and drug resistance of the isolated pathogens were analyzed. The biological characteristics of highly virulent Klebsiella pneumoniae ATCC43816 and its rcsB deletion strains were compared by growth curve test, viscosity semi quantitative test, uronic acid quantitative test and drug sensitivity test. ResultsA total of 1,077 strains of pathogenic bacteria were isolated, and the top 3 pathogens were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa (23.96%, 17.46%, 11.23%). Klebsiella pneumoniae had high resistance rates to cefazolin, ampicillin/sulbactam and cefuroxime. Compared with the wild strain, the MIC values of imipenem, ampicillin/sulbactam and tegacyclin in {Delta}rcsB was decreased. ConclusionKlebsiella pneumoniae should be the focus of bacterial drug resistance monitoring in order to guide early anti-infection treatment. rcsB may indirectly regulate the drug resistance of Klebsiella pneumoniae by regulating the amount of capsule formation, which is of great significance for improving the drug resistance status of Klebsiella pneumoniae.

microbiology↗

bioRxiv2022

An oral vaccine for SARS-CoV-2 RBD mRNA-bovine milk-derived exosomes induces a neutralizing antibody response in vivo

The severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) that causes the coronavirus disease 2019 (COVID-19) has presented numerous challenges to global health. The vaccines, including lipid-based nanoparticle mRNA, inactivated virus and recombined protein, have been used to prevent SARS-CoV-2 infections in clinics and are immensely helpful against the epidemic. Here, we first present an oral mRNA vaccine based on bovine milk-derived exosomes (milk-exos), which encodes the SARS-CoV-2 receptor binding domain (RBD) as an immunogen. The results indicated that RBD mRNA delivered by milk-derived exosomes can produce secreted RBD peptide in 293 cells in vitro and stimulated neutralizing antibodies against RBD in mice. These results indicated that bovine milk-derived exosome-based mRNA vaccine could serve as a new strategy for preventing SARS-CoV-2 infection. Meanwhile, it also can work as a new oral delivery system for mRNA. One Sentence SummaryOral SARS-CoV-2 mRNA vaccine based on bovine milk-derived exosomes can stimulate neutralizing antibodies in mice.

immunology↗

bioRxiv2022

Diversity and ecological function of urease-producing bacteria in the cultivation environment of Gracilariopsis lemaneiformis

Urease-producing bacteria (UPB) provide inorganic nitrogen for primary producers by hydrolysis of urea. They play an important role in marine nitrogen cycle. However, there is still incomplete understanding of UPB and their ecological functions in the cultivation environment of red macroalage Gracilariopsis lemaneiformis. This study comprehensively analyzed the diversity of culturable UPB and explored their effects on urea uptake by G. lemaneiformis. Total 34 isolates belonging to four main bacterial phyla i.e. Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria were identified through 16S rRNA sequencing and were screened for UPB by urea agar chromogenic medium assay and ureC gene cloning. Our data revealed that only 8 strains were found containing urease. These all UPB exhibited different urease activities by Berthelot reaction colorimetry assay. Furthermore, UPB with highest urease activity was selected to use as co-culture with G. lemaneiformis to explore its role in terms of promotion or inhibition of nitrogen uptake by G. lemaneiformis. The results showed that the urea consumption in culture media and the total cellular nitrogen in G. lemaneiformis found increased significantly in the UPB-co culture group than control i.e. in the sterile group (p < 0.05). Similarity, isotopic assay revealed that {delta}15N contents of G. lemaneiformis was significant higher in the UPB-co culture than in the control where {delta}15N-urea was the only nitrogen source in the culture media, indicating the UPB helped G. lemaneiformis to absorb more nitrogen from urea. Moreover, the highest content of {delta}15N was found in G. lemaneiformis with epiphytic bacteria, as compared to sterilized (control) showing that epiphytic bacteria along with UPB have compound effects in helping G. lemaneiformis absorb more nitrogen in urea. Taken together, these results provide unique insight into the ecological role of UPB and suggest that urease from macroalgae environment-associated bacteria might be important player in the marine nitrogen cycling. ImportanceTo the best of our knowledge, this is the first study ever conducted to isolate the culturable UPB from the cultivation environment of G. lemaneiformis by urea agar chromogenic medium assay, and also evaluate the effects of UPB on urea utilization in G. lemaneiformis by stable isotopic tracer technique. This study provides a new insight into the mechanism of organic nitrogen uptake and utilization in G. lemaneiformis, and is of great significance for a better understanding of the ecological role of functional bacteria (e.g. urease-producing bacteria) in the marine nitrogen cycling.

microbiology↗

bioRxiv2022

Tryptophan-like side chain holding aptamers inhibit respiratory syncytial virus infection of lung epithelial cells

Respiratory syncytial virus (RSV) is a leading cause of serious and even fatal acute lower respiratory tract infections in infants and in the elderly. Potent RSV neutralization has been achieved by antibodies that selectively bind the prefusion form of the viral fusion (F) protein. We hypothesised that similar potent neutralization could be achieved using F protein targeting aptamers. Aptamers have yet to reach their translational potential for therapeutics or diagnostics due to their short half-life and limited range of target-aptamer interactions; these shortcomings can, however, be ameliorated by application of amino acid-like side chain holding nucleotides. In this study, a stabilized version of the prefusion RSV F protein was targeted by aptamer selection using an oligonucleotide library holding a tryptophan-like side chain. This process resulted in aptamers that bound the F protein with high affinity and differentiated between pre- and postfusion conformation. Identified aptamers inhibited viral infection of lung epithelial cells. Moreover, introduction of modified nucleotides extended aptamer half-lives. Our results suggest that targeting aptamers to the surface of viruses could yield effective drug candidates, which could keep up with the pace of the continuously evolving pathogens.

molecular biology↗

bioRxiv2022

A stable reference human transcriptome and proteome as a standard for reproducible omics experiments

In recent years, the development of high-throughput omics technology has greatly promoted the development of biomedicine. However, the poor reproducibility of omics techniques limits its application. It is necessary to use standard reference materials of complex RNAs or proteins to test and calibrate the accuracy and reproducibility of omics workflows. However, the transcriptome and proteome of most cell lines shift during culturing, which limits their applicability to serve as standard samples. In this study, we demonstrated that the human hepatocellular cell line MHCC97H has a very stable transcriptome (R2=0.966-0.995) and proteome (R2=0.934-0.976 for DDA, R2=0.942-0.986 for DIA) after 9 subculturing generations, which allows this stable standard sample to be stably produced on an industrial scale for several decades. Moreover, this stability was maintained across labs and platforms. In sum, our results justified a omics standard reference material and reference datasets for transcriptomic and proteomics research. This helps to further standardize the workflow and data quality of omics techniques and thus promotes the application of omics technology in precision medicine.

cell biology↗

bioRxiv2022

Born with intronless ERF transcriptional factors: C4 photosynthesis inherits a legacy dating back 450 million years

The genus Flaveria, containing species at different evolutionary stages of the progression from C3 to C4 photosynthesis, is used as a model system to study the evolution of C4 photosynthesis. Here, we report chromosome-scale genome sequences for five Flaveria species, including C3, C4, and intermediate species. Our analyses revealed that both acquiring additional gene copies and recruiting ethylene responsive factor (ERF) cis-regulatory elements (CREs) contributed to the emergence of C4 photosynthesis. ERF transcriptional factors (TFs), especially intronless ERF TFs, were co-opted in dicotyledonous C4 species and monocotyledonous C4 species in parallel. These C4 species co-opted intronless ERF TFs originated from the Late Ordovician mass extinction that occurred [~]450 million years ago in coping with environmental stress. Therefore, this study demonstrated that intronless ERF TFs were acquired during the early evolution of plants and provided the molecular toolbox facilitating multiple subsequent independent evolutions of C4 photosynthesis.

evolutionary biology↗

bioRxiv2022

Molecular and genetic mechanisms conferring dissolution of dioecy in Diospyros oleifera Cheng

Dioecy, a sexual system of single-sex (gynoecious/androecious) individuals, is rare in flowering plants. This rarity may be a result of the frequent transition from dioecy into systems with co-sex individuals. Here, we report potential molecular and genetic mechanisms that underlie the dissolution of dioecy to monoecy and andro(gyno)monoecy, based on multiscale genome-wide investigations of 150 accessions of Diospyros oleifera. All co-sex D. oleifera plants, including monoecious and andro(gyno)monoecious individuals, possessed the male determinant gene OGI, implying that genetic factors control gynoecia development in genetically male D. oleifera. In both single- and co-sex plants, female function was expressed in the presence of a genome-wide decrease in methylation levels, along with sexually distinct regulatory networks of smRNAs and their targets. Furthermore, a genome-wide association study (GWAS) identified a genomic region and a DUF247 gene cluster strongly associated with the monoecious phenotype, as well as several regions that may contribute to andromonoecy. Collectively, our findings imply stable breakdown of the dioecious system in D. oleifera, presumably a result of the genomic features of the sex-linked region.

plant biology↗

bioRxiv2022

"Double-Effect" strategy against Triple-Negative Breast Cancer via a synergistic therapy of Magneto-mechanical Force enhancing NIR-II Hypothermal Ablation

Triple-negative breast cancer (TNBC) is a form of breast cancer that is more aggressive and harder to treat than others, with a higher probability of relapse. Its highly efficient capabilities for migrating and invading other parts of the body together with the current lack of clinically established effective therapies account for a low survival rate. Thus, we propose the in-tandem use of two complementary therapeutic routes to effectively combat TNBC. Herein, a versatile magnetic-photothermal converter (MPC) is elaborately designed via integrating zinc-doped ferrite nanoparticles and polyethene glycol, synergistically enhanced through magneto-mechanical force (MMF) and near-infrared-II (NIR-II) hypothermal ablation, thereby displaying excellent therapeutic efficiency. Their combined use, which is less aggressive to the human body compared to conventional chemotherapeutic approaches, results in the splendid suppression of TNBC migration and invasion. Remotely controlling the MPCs by an external magnetic stimulus, results in cellular MMF effects that cause direct mechanical destruction to the cancer cell membrane, leading to its necrosis. Furthermore, the MMF disrupts intracellular lysosomes, thereby triggering the release of large amounts of protein hydrolases, which induce intracellular oxidative stress, and accelerate the induction of apoptosis. Complementing the therapeutic approach based on MMF, the excellent photothermal performance of the MPC in the NIR-II region (1064nm) is exploited to enable effective hypothermal ablation of the tumours, which can be achieved in deep tissue layers. The proposed multifunctional nanocomposites, together with the demonstrated "double effect" therapeutic approach, hold significant potential to pave the way for future cutting-edge weapons against the dreadful TNBC.

cancer biology↗

bioRxiv2022

Identify the origin and end cells and infer the trajectory of cellular fate automatically

Cellular state identification and trajectory inference enable reconstructions of cell fate dynamics from single-cell RNA sequencing. However, the identification of cell fate trajectories requires a large number of computational resources or known biological process, and lack a method to alleviate both of these deficiencies at the same time. Here, we present scLTNN, a method that automatically infers origin and end cell state from scRNA-seq data and calculates the developmental trajectory and differentiation direction of cells with only a few computational resources and time consummation. We apply scLTNN to disentangling subpopulation kinetics in CD8+ T cell, pancreatic endocrinogenesis, and the development of zebrafish embryos. scLTNN displays a strong trajectory inference ability cross-species. scLTNN features a modular design that can be flexibly extended to any scRNA-seq analysis task. The complete package is available online at https://github.com/Starlitnightly/scltnn.

bioinformatics↗

bioRxiv2022

LncDLSM: Identification of Long Non-coding RNAs with Deep Learning-based Sequence Model

Long non-coding RNAs (LncRNAs) serve a vital role in regulating gene expressions and other biological processes. Differentiation of lncRNAs from protein-coding transcripts helps researchers dig into the mechanism of lncRNA formation and its downstream regulations related to various diseases. Previous works have been proposed to identify lncRNAs, including traditional bio-sequencing and machine learning approaches. Considering the tedious work of biological characteristic-based feature extraction procedures and inevitable artifacts during bio-sequencing processes, those lncRNA detection methods are not always satisfactory. Hence, in this work, we presented lncDLSM, a deep learning-based framework differentiating lncRNA from other protein-coding transcripts without dependencies on prior biological knowledge. lncDLSM is a helpful tool for identifying lncRNAs compared with other biological feature-based machine learning methods and can be applied to other species by transfer learning achieving satisfactory results. Further experiments showed that different species display distinct boundaries among distributions corresponding to the homology and the specificity among species, respectively. An online web server is provided to the community for easy use and efficient identification of lncRNA, available at http://39.106.16.168/lncDLSM.

bioinformatics↗

bioRxiv2022

The transcriptional regulator JAZ8 interacts with the C2 protein from geminiviruses and limits the viral infection in Arabidopsis

Jasmonates (JAs) are phytohormones that finely regulate critical biological processes, including plant development and defense. JASMONATE ZIM-DOMAIN (JAZ) proteins are crucial keeping JA-responsive genes in a repressed state. In the presence of JA-Ile, JAZ repressors are ubiquitinated and targeted for degradation by the ubiquitin/proteasome system, allowing the activation of the downstream transcription factors and, consequently, the activation of JA-responsive genes. A growing body of evidence has shown that JA signalling is crucial in defending against plant viruses and their insect vectors. Here, we describe the interaction of C2 proteins from two geminiviruses from the genus Begomovirus, tomato yellow curl Sardinia virus (TYLCSaV) and tomato yellow leaf curl virus (TYLCV), with the transcriptional repressor JAZ8 from Arabidopsis thaliana and its closest orthologue in tomato, SlJAZ9. Both JAZ and C2 proteins colocalize in the nucleus, forming discrete nuclear speckles. Overexpression of JAZ8 did not lead to altered responses to TYLCV infection; however, knock-down of JAZ8 favours the geminiviral infection in plants. Low levels of JAZ8 likely affect the viral infection specifically since JAZ8-silenced plants do not display developmental phenotypes nor present differences in their interaction with the viral insect vector. Our results show that JAZ8 interacts with geminiviral C2 proteins and exerts an anti-geminiviral effect.

plant biology↗

bioRxiv2022

Ploidy variation and spontaneous haploid-diploid switching of Candida glabrata clinical isolates

The human fungal pathogen Candida glabrata is phylogenetically closely related to Saccharomyces cerevisiae, a model eukaryotic organism. Unlike S. cerevisiae with both haploid and diploid forms and a complete sexual cycle, C. glabrata has long been considered a haploid and asexual species. In this study, we analyzed the ploidy states of 500 clinical isolates of C. glabrata from four Chinese hospitals and found that approximately 4% of the isolates were in or able to spontaneously switch to an aneuploidy (genomic DNA: 1N-2N), diploidy (2N), or hyperdiploid (>2N) form under in vivo or in vitro conditions. Stable diploid-form cells were identified in 3% of the isolates (15/500). Of particular interest, one clinical strain only existed in the diploid form. Multilocus sequence typing (MLST) assays revealed two major genetic clusters (A and B) of C. glabrata isolates. Most of the isolates (70%) from China belonged to the A cluster, whereas most of the isolates from other countries (such as Iran, Japan, USA, and European countries) belonged to the B cluster. Further investigation indicated that C. glabrata cells of different ploidy forms differed in a number of aspects, including morphologies, antifungal susceptibility, virulence, and global gene expression profiles. Additionally, C. glabrata could undergo spontaneous switching between the diploid and haploid form under both in vitro and in vivo conditions. Given the absence of an apparent sexual phase, one would expect that the ploidy shifts could function as an alternative strategy that promotes genetic diversity and benefits the ability of the fungus to rapidly adapt to the changing environment. ImportanceThe human fungal pathogen Candida glabrata has long been thought to be a haploid organism. Here we report the population structure and ploidy states of 500 clinical isolates of C. glabrata from China. To our surprise, we found that the ploidy of a subset of clinical isolates varied dramatically. Some isolates were in or able to switch to an aneuploid, diploid, or hyperdiploid form. C. glabrata cells with different ploidy differed in a number of biological aspects, including morphologies, antifungal susceptibility, virulence, and global gene expression profiles. Given the absence of an apparent sexual phase in this fungus, we propose that ploidy switching could be a rapid adaption strategy to environmental changes and could function as an alternative strategy of sexual reproduction.

microbiology↗

bioRxiv2021

Subgenomic SARS-CoV-2 replicon and reporter replicon cell lines enable ultrahigh throughput antiviral screening and mechanistic studies with antivirals, viral mutations or host factors that affect COVID-19 replication

Replicon-based technologies were used to develop reagents and assays for advanced drug discovery efforts against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and for examining all facets of the SARS-CoV-2 replication cycle at reduced biocontainment level. Specifically: a) 21 replicons were cloned in bacterial artificial chromosomes (BACs) and delivered as transfectable plasmid DNA or transcribed RNA in various cell types. Replicons carrying mutations that affect the activity or antiviral susceptibility of SARS-CoV-2 enzymes were used to establish utility for mechanistic studies while reducing the community risks associated with gain-of-function studies in fully infectious virus. b) A BHK-21 stable cell line harboring SARS-CoV-2 replicon was generated and characterized in robust high/ultra-high throughput assays of antiviral efficacy with orthogonal SARS-CoV-2 replication reporter genes (Nano luciferase and enhanced green fluorescent protein-eGFP); the estimated antiviral potencies in the fully infectious SARS-CoV-2 system and in the transient or stable replicon systems were similar. HEK293 and Calu1 stable cell lines expressing SARS-CoV-2 replicon have also been prepared. Finally, c) we generated trans-encapsidated replicons by co-expression with SARS-CoV-2 structural proteins, thus producing single-round infectious SARS-CoV-2 virus-like particles that are able to transduce susceptible cell types and have expanded utility to enable study of virion assembly and entry into target cells. Hence, these SARS-CoV-2 replicon-based reagents include a novel approach to replicon-harboring cell line generation and are valuable tools that can be used at lower biosafety level (BSL2) for drug discovery efforts, characterization of SARS-CoV-2 and variant evolution in the COVID-19 pandemic, mechanisms of inhibition and resistance, and studies on the role of SARS-CoV-2 genes and host dependency factors.

microbiology↗