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Du, H.

Publications and source records attributed to Du, H..

At least 91 records · Page 5Linked to original sources

Genome Assemblies of the Warthog and Kenyan Domestic Pig Provide Insights into Suidae Evolution and Candidate Genes for African Swine Fever Tolerance

As warthog (Phacochoerus africanus) has innate immunity against African swine fever (ASF), it is critical to understand the evolutionary novelty of warthog to explain its specific ASF resistance. Here, we present two completed new genomes of one warthog and one Kenyan domestic pig, as the fundamental genomic references to decode the genetic mechanism on ASF tolerance. Our results indicated, multiple genomic variations, including gene losses, independent contraction and expansion of specific gene families, likely moulded warthogs genome to adapt the environment. Importantly, the analysis of the presence and absence of genomic sequences revealed that, the warthog genome had a DNA sequence absence of the lactate dehydrogenase B (LDHB) gene on chromosome 2 compared to the reference genome. The overexpression and siRNA of LDHB indicated that its inhibition on the replication of ASFV. Combining with large-scale sequencing data of 123 pigs from all over the world, contraction and expansion of TRIM genes families revealed that TRIM family genes in the warthog genome were potentially responsible for its tolerance to ASF. Our results will help further improve the understanding of genetic resistance ASF in pigs.

genetics↗

Disordered climate threatens short-distance migrants

Global climate change has led to a warmer world, changing the migratory and breeding behaviors of many species, and short-distance migrants may benefit from climate change. With climate change leading to an increasingly disordered climate, we show here that a disordered spring climate disturbs the migration and breeding of a short-distance anadromous fish. In 2020, on the Qinghai-Tibetan Plateau, an abnormally low temperature in April delayed the migration rhythm of Gymnocypris przewalskii by nearly 10 days, while the gonadal development rhythm of the breeding population was almost normal. The phenology mismatch decreased the migrating populations by 30-70%, reducing the larval flux by nearly 80%. This case reveals that for short-distance migrants, different phenologies within the same species respond to disordered climates differently, which leads to phenology mismatches and then threatens the species. Along with increasing local extreme weather and climate events, short-distance migrants need more attention and conservation actions.

ecology↗

Molecular basis and evolutionary cost of a novel phenotype of macrolides/lincosamides resistance in Staphylococcus haemolyticus

Staphylococcus haemolyticus (S. haemolyticus) is a coagulase-negative Staphylococcus and has become one of the primary pathogens of nosocomial infections. After a long period using the antibiotics against the infections caused by S. haemolyticus, S. haemolyticus developed several resistance phenotypes of macrolides and lincosamides. Here, we acquired four S. haemolyticus clinical isolates, of which three isolates demonstrated antibiotic resistance as reported previously, while one was resistant to both erythromycin and clindamycin without erythromycin induction. Such novel phenotype, known as constitutive Macrolides-Lincosamides-Streptogramins (MLS) resistance, was reported in other bacteria, but it was found for the first time in S. haemolyticus. To further investigate such behavior, we confirmed that the deletion of the methyltransferase ErmC upstream leader peptide was critical to cause constitutive MLS resistance based on the analysis of potential antibiotic resistance genes via whole-genome sequencing and experimental verification. In addition, we discovered that the continuous expression of ErmC may inhibit the growth of S. haemolyticus, which turned out to be the cost with no MLS pressure. Taken together, this study firstly reported the constitutive MLS resistance in S. haemolyticus, and provided new ideas for using macrolides and lincosamides in clinical treatment.

microbiology↗

Interleukin-6 mediates PSAT1 expression and serine metabolism in TSC2-deficient cells

Tuberous sclerosis complex (TSC) and lymphangioleiomyomatosis (LAM) are caused by aberrant mechanistic Target of Rapamycin Complex 1 (mTORC1) activation due to loss of either TSC1 or TSC2. Cytokine profiling of TSC2-deficient LAM patient-derived cells revealed striking upregulation of Interleukin-6 (IL-6). LAM patient plasma contained increased circulating IL-6 compared with healthy controls, and TSC2-deficient cells showed upregulation of IL-6 transcription and secretion compared to wildtype cells. IL-6 blockade repressed the proliferation and migration of TSC2-deficient cells and reduced oxygen consumption and extracellular acidification. U-13C glucose tracing revealed that IL-6 knockout reduced 3-phosphoserine and serine production in TSC2-deficient cells, implicating IL-6 in de novo serine metabolism. IL-6 knockout reduced expression of phosphoserine aminotransferase 1 (PSAT1), an essential enzyme in serine biosynthesis. Importantly, recombinant IL-6 treatment rescued PSAT1 expression in the TSC2-deficient, IL-6 knockout clones selectively and had no effect on wildtype cells. Treatment with anti-IL-6 (aIL-6) antibody similarly reduced cell proliferation and migration and reduced renal tumors in Tsc2+/- mice, while reducing PSAT1 expression. These data reveal a novel mechanism through which IL-6 regulates serine biosynthesis, with potential relevance to the therapy of tumors with mTORC1 hyperactivity. ClassificationMajor category: Biological Sciences Minor category: Cell Biology

pathology↗

AutoVEM2: a flexible automated tool to analyze candidate key mutations and epidemic trends for virus

In our previous work, we developed an automated tool, AutoVEM, for real-time monitoring the candidate key mutations and epidemic trends of SARS-CoV-2. In this research, we further developed AutoVEM into AutoVEM2. AutoVEM2 is composed of three modules, including call module, analysis module, and plot module, which can be used modularly or as a whole for any virus, as long as the corresponding reference genome is provided. Therefore, its much more flexible than AutoVEM. Here, we analyzed three existing viruses by AutoVEM2, including SARS-CoV-2, HBV and HPV-16, to show the functions, effectiveness and flexibility of AutoVEM2. We found that the N501Y locus was almost completely linked to the other 16 loci in SARS-CoV-2 genomes from the UK and Europe. Among the 17 loci, 5 loci were on the S protein and all of the five mutations cause amino acid changes, which may influence the epidemic traits of SARS-CoV-2. And some candidate key mutations of HBV and HPV-16, including T350G of HPV-16 and C659T of HBV, were detected. In brief, we developed a flexible automated tool to analyze candidate key mutations and epidemic trends for any virus, which would become a standard process for virus analysis based on genome sequences in the future. HighlightsO_LIAn automatic tool to quickly analyze candidate key mutations and epidemic trends for any virus was developed. C_LIO_LIOur integrated analysis method and tool could become a standard process for virus mutation and epidemic trend analysis based on genome sequences in the future. C_LIO_LIN501Y with the other 16 highly linked mutation sites of SARS-CoV-2 in the UK and Europe were further confirmed, and some valuable mutation sites of HBV and HPV-16 were detected. C_LI

genomics↗

A multifaceted role of progranulin in regulating amyloid-beta dynamics and responses

Haploinsufficiency of progranulin (PGRN) is a leading cause of frontotemporal lobar degeneration (FTLD). PGRN polymorphisms are associated with Alzheimers disease (AD). PGRN is highly expressed in the microglia near A{beta} plaques and influences plaque dynamics and microglial activation. However, the detailed mechanisms remain elusive. Here we report that PGRN deficiency reduces human APP and A{beta} levels in the young male but not female mice. PGRN deficient microglia exhibit increased expression of markers associated with microglial activation, including CD68, Galectin-3, TREM2 and GPNMB, specifically near A{beta} plaques. In addition, PGRN loss leads to up-regulation of lysosome proteins and an increase in the nuclear localization of TFE3, a transcription factor involved in lysosome biogenesis. Cultured PGRN deficient microglia show enhanced nuclear translocation of TFE3 and inflammation in response to A{beta} fibril treatment. Taken together, our data revealed a sex- and age-dependent effect of PGRN on amyloid metabolism and a role of PGRN in regulating lysosomal activities and inflammation in plaque-associated microglia, which may contribute to the disease mechanism associated with PGRN polymorphisms in AD.

neuroscience↗

Mutation Profiles, Glycosylation Site Distribution and Codon Usage Bias of HPV16

Human papillomavirus type 16 (HPV16) is the most prevalent HPV type causing cervical cancers. Herein, using 1,597 full genomes of HPV16, we systemically investigated the mutation profiles, surface protein glycosylation sites and the codon usage bias of the eight open reading frames (ORFs) of HPV16 genomes from different lineages and sublineages. Multiple lineage- or sublineage-specific mutation sites were identified. Glycosylation analysis showed that HPV16 lineage D contained the highest number of unique potential glycosylation site in both L1 and L2 capsid protein, which might lead to their antigenic distances from other HPV16 lineages. Nucleotide composition of HPV16 showed that the overall AT content was higher than GC content at the 3rd codon position. Relatively high ENC values suggested that the HPV16 ORFs didnt have strong codon usage bias. Most of the HPV16 ORFs were mainly governed by natural selection pressure such as translational pressure, except for L2. HPV16 only shared some of the preferred codons with human, which might help reduce competition in translational resources. These findings may help increase our understanding of the heterogeneity between HPV16 lineages and sublineages, and the adaptation mechanism of HPV in human cells, which might facilitate HPV classification and improve vaccine development and application.

genomics↗

Molecular dynamics simulation study of effects of key mutations in SARS-CoV-2 on protein structures

SARS-CoV-2 has been spreading rapidly since 2019 and has produced large-scale mutations in the genomes. The mutation in genes may lead to changes in protein structure, which would have a great impact on the epidemiological characteristics. In this study, we selected the key mutations of SARS-CoV-2 from a real-time monitoring tool, including D614G, A222V, N501Y, T716I, S982A, D1118H of spike (S) protein, and performed molecular dynamics (MD) simulations on single-site mutant D614G, double-site mutant D614G&A222V and penta-site mutant N501Y&D614G&T716I&S982A&D1118H to investigate their effects on protein structure and stability using molecular dynamics (MD) simulations. The results suggested that D614G improved the stability of S protein, while D614G&A222V and N501Y&D614G&T716I&S982A&D1118H showed an increased solvent accessible surface area and they might enhance the ability of protein to react with the outside environment. Our findings could complement the mechanistic link between genotype--phenotype--epidemiological characteristics in the study of SARS-CoV-2. We also found no significant difference between the antigenicity of S protein and the mutants through Ellipro, which may reference for vaccine development and application.

bioinformatics↗

Differential regulation of progranulin derived granulin peptides

Haploinsufficiency of progranulin (PGRN) is a leading cause of frontotemporal lobar degeneration (FTLD). PGRN is comprised of 7.5 granulin repeats and is processed into individual granulin peptides in the lysosome. However, very little is known about the levels and regulations of individual granulin peptides due to the lack of specific antibodies. Here we report the generation and characterization of antibodies specific to each granulin peptide. We found that the levels of granulins C, E and F are differentially regulated compared to granulins A and B. Furthermore, we demonstrated that granulin B, C and E are heavily glycosylated and the glycosylation pattern of granulin C varies in different physiological and pathological conditions. Deficiency of lysosomal proteases leads to alterations in the levels of a specific subset of granulins. These data support that the levels of individual granulin peptides are differentially regulated under physiological and pathological conditions and provide novel insights into how granulin peptides function in the lysosome.

neuroscience↗

Real-time monitoring epidemic trends and key mutations in SARS-CoV-2 evolution by an automated tool

With the global epidemic of SARS-CoV-2, it is important to monitor the variation, haplotype subgroup epidemic trends and key mutations of SARS-CoV-2 over time effectively, which is of great significance to the development of new vaccines, the update of therapeutic drugs, and the improvement of detection reagents. The AutoVEM tool developed in the present study could complete all mutations detections, haplotypes classification, haplotype subgroup epidemic trends and key mutations analysis for 131,576 SARS-CoV-2 genome sequences in 18 hours on a 1 core CPU and 2G internal storage computer. Through haplotype subgroup epidemic trends analysis of 131,576 genome sequences, the great significance of the previous 4 specific sites (C241T, C3037T, C14408T and A23403G) was further revealed, and 6 new mutation sites of highly linked (T445C, C6286T, C22227T, G25563T, C26801G and G29645T) were discovered for the first time that might be related to the infectivity, pathogenicity or host adaptability of SARS-CoV-2. In brief, we proposed an integrative method and developed an efficient automated tool to monitor haplotype subgroup epidemic trends and screen out the key mutations in the evolution of SARS-CoV-2 over time for the first time, and all data could be updated quickly to track the prevalence of previous key mutations and new key mutations because of high efficiency of the tool. In addition, the idea of combinatorial analysis in the present study can also provide a reference for the mutation monitoring of other viruses.

genomics↗

Template-independent genome editing and repairing correct frameshift disease in vivo

Frameshift mutation caused by small insertions/deletions (indels) often generate truncated and non-functional proteins, which underlies 22% inherited Mendelian disorders in humans. However, there is no efficient in vivo gene therapy strategies available to date, especially in postmitotic systems. Here, we leveraged the non-homologous end joining (NHEJ) mediated non-random editing profiles to compensate the frameshift mutation in a USH1F mouse model - av3j. After treatment by the selected gRNA, about 50% editing products showed reading-frame restoration, and more than 70% targeted hair cells recovered mechanotransduction. In vivo treatment ameliorated the hearing and balance symptoms in homozygous mutant mice. Furthermore, a scale-up analysis of 114 gRNAs targeting 40 frameshift deafness mutations reveals that 65% loci have at least one gRNA with predicted therapeutic potential. Together, our study demonstrates that the NHEJ-mediated frame restoration is a simple and highly efficient therapeutic strategy for small-indel induced frameshift mutations.

neuroscience↗

Network-based Virus-Host Interaction Prediction with Application to SARS-CoV-2

COVID-19, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has quickly become a global health crisis since the first report of infection in December of 2019. However, the infection spectrum of SARS-CoV-2 and its comprehensive protein-level interactions with hosts remain unclear. There is a massive amount of under-utilized data and knowledge about RNA viruses highly relevant to SARS-CoV-2 and their hosts proteins. More in-depth and more comprehensive analyses of that knowledge and data can shed new insight into the molecular mechanisms underlying the COVID-19 pandemic and reveal potential risks. In this work, we constructed a multi-layer virus-host interaction network to incorporate these data and knowledge. A machine learning-based method, termed Infection Mechanism and Spectrum Prediction (IMSP), was developed to predict virus-host interactions at both protein and organism levels. Our approach revealed five potential infection targets of SARS-CoV-2, which deserved public health attention, and eight highly possible interactions between SARS-CoV-2 proteins and human proteins. Given a new virus, IMSP can utilize existing knowledge and data about other highly relevant viruses to predict multi-scale interactions between the new virus and potential hosts.

bioinformatics↗

Derivation of human extended pluripotent stem cells in feeder-free condition

Human extended pluripotent stem cells (EPSCs), with bidirectional chimeric ability to contribute to both embryonic and extra-embryonic lineages, can be obtained and maintained by converting embryonic stem cells (ESCs) using chemicals. However, the transition system is based on inactivated mouse fibroblast, which greatly hinders the mechanistic studies of extended pluripotency and further applications. Here we reported a Matrigel-based feeder-free method to convert human ESCs and iPSCs into EPSCs and demonstrated the extended pluripotency in terms of molecular features, chimeric ability, and transcriptome. We further improved the protocol by applying chemicals targeting glycolysis and histone methyltransferase. Altogether, our data established a feeder-free system to generate human EPSCs and provided additional insights into the acquisition of extended pluripotency.

developmental biology↗

Ceftazidime Is a Potential Drug to Inhibit SARS-CoV-2 Infection In Vitro by Blocking Spike Protein-ACE2 Interaction

Coronavirus Disease 2019 (COVID-19) spreads globally as a sever pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Cell entry of SARS-CoV-2 mainly depends on binding of the viral spike (S) proteins to angiotensin converting enzyme 2 (ACE2) on host cells. Therefore, repurposing of known drugs to inhibit S protein-ACE2 interaction could be a quick way to develop effective therapy for COVID-19. Using a high-throughput screening system to investigate the interaction between spike receptor binding domain (S-RBD) and ACE2 extracellular domain, we screened 3581 FDA-approved drugs and natural small molecules and identified ceftazidime as a potent compound to inhibit S-RBD-ACE2 interaction by binding to S-RBD. In addition to significantly inhibit S-RBD binding to HPAEpiC cells, ceftazidime efficiently prevented SARS-CoV-2 pseudovirus to infect ACE2-expressing 293T cells. The inhibitory concentration (IC50) was 113.2 M, which is far below the blood concentration (over 300 M) of ceftazidime in patients when clinically treated with recommended dose. Notably, ceftazidime is a drug clinically used for the treatment of pneumonia with minimal side effects compared with other antiviral drugs. Thus, ceftazidime has both anti-bacterial and anti-SARS-CoV-2 effects, which should be the first-line antibiotics used for the clinical treatment of COVID-19.

immunology↗

Species packing and the latitudinal gradient in local beta-diversity

The decline in species richness at higher latitudes is among the most fundamental patterns in ecology. Whether changes in species composition across space (beta-diversity) contribute to this gradient of overall species richness (gamma-diversity) remains hotly debated. Previous studies that failed to resolve the issue suffered from a well-known tendency for small samples in areas with high gamma-diversity to have inflated measures of beta-diversity. Here, we provide here a novel analytical test, using beta-diversity metrics that correct the gamma-diversity and sampling biases, to compare beta-diversity and species packing across a latitudinal gradient in tree species richness of 21 large forest plots along a large environmental gradient in East Asia. We demonstrate that after accounting for topography and correcting the gamma-diversity bias, tropical forests still have higher beta-diversity than temperate analogs. This suggests that beta-diversity contributes to the latitudinal species richness gradient as a component of gamma-diversity. Moreover, both niche specialization and niche marginality (a measure of niche spacing along an environmental gradient) also increase towards the equator, after controlling for the effect of topographic heterogeneity. This supports the joint importance of tighter species packing and larger niche space in tropical forests while also demonstrating the importance of local processes in controlling beta-diversity.

ecology↗

RNF219 interacts with CCR4-NOT in regulating stem cell differentiation

Regulation of RNA stability plays a crucial role in gene expression control. Deadenylation is the initial rate-limiting step for the majority of RNA decay events. Here, we show that RING Finger Protein 219 (RNF219) interacts with the CCR4-NOT deadenylase complex. RNF219-CCR4-NOT exhibits deadenylation activity in vitro. RNA-seq analyses identify some of the 2-cell specific genes and the neuronal genes significantly down-regulated upon RNF219 knockdown, while up-regulated after depletion of the CCR4-NOT subunit CNOT10 in mouse embryonic stem (ES) cells. RNF219 depletion leads to impaired neuronal lineage commitment during ES cell differentiation. Our study suggests that RNF219 is a novel interacting partner of CCR4-NOT, and required for maintenance of ES cell pluripotency.View Full Text

molecular biology↗

Annexina2 as atarget protein for chlorogenic acidin human lung cancerA549cells

Chlorogenic acid, an important active component of coffee with anti-tumor activities, has been found for many years. However, the lack of understanding about its target proteins greatly limits the exploration of its anti-tumor molecular mechanism and clinical application. Here, in vitro and animal experiments showed that chlorogenic acid had a significant inhibitory effect on the proliferation of A549 cells. Using the spontaneous fluorescence characteristic of chlorogenic acid to screen the target proteins cleverly to avoid the problem of chemical modification increasing false positive, we identify and verify annexin A2 (ANXA2) as a covalent binding target of chlorogenic acid in A549 cells. Then, we discover that chlorogenic acid as an inhibitor of the binding of ANXA2 to p50 subunit inhibited the expression of downstream anti-apoptotic genes cIAP1 and cIAP2 of NF-κB signaling pathway in A549 cells in vitro and vivo. Moreover, we find chlorogenic acid hindered the binding of ANXA2 and actin maybe involved in the impediment of tumor cell cycle and migration. Thus, this work demonstrates that chlorogenic acid, as a binding ligand of ANXA2, decrease the expression of NF-κB downstream anti-apoptotic genes, inhibiting the proliferation of A549 cells in vivo and vitro.View Full Text

pharmacology and toxicology↗

Transcriptional Profiling Reveals the Transcription Factor Networks Regulating the Survival of Striatal Neurons

The striatum is structurally highly diverse, and its organ functionality critically depends on normal embryonic development. Although several studies have been conducted on the gene functional changes that occur during striatal development, a system-wide analysis of the underlying molecular changes is lacking. Here, we present a comprehensive transcriptome profile that allowed us to explore the trajectory of striatal development and identify the correlation between the striatal development and Huntingtons disease (HD). Furthermore, we applied an integrative transcriptomic profiling approach based on machine learning to systematically map a global landscape of 277 transcription factor (TF) networks. Most of these TF networks are linked to biological processes, and some unannotated genes provide information about the corresponding mechanisms. For example, we found that the Meis2 and Six3 were crucial for the survival of striatal neurons, which was verified using conditional knockout (CKO) mice. Finally, we used RNA-Seq to speculate their downstream targets.

neuroscience↗