RESUMO
African swine fever virus (ASFV) is a large, double-stranded DNA virus that causes a fatal disease in pigs, posing a threat to the global pig industry. Whereas some ASFV proteins have been found to play important roles in ASFV-host interaction, the functional roles of many proteins are still largely unknown. In this study, we identified I73R, an early viral gene in the replication cycle of ASFV, as a key virulence factor. Our findings demonstrate that pI73R suppresses the host innate immune response by broadly inhibiting the synthesis of host proteins, including antiviral proteins. Crystallization and structural characterization results suggest that pI73R is a nucleic-acid-binding protein containing a Zα domain. It localizes in the nucleus and inhibits host protein synthesis by suppressing the nuclear export of cellular messenger RNA (mRNAs). While pI73R promotes viral replication, the deletion of the gene showed that it is a nonessential gene for virus replication. In vivo safety and immunogenicity evaluation results demonstrate that the deletion mutant ASFV-GZΔI73R is completely nonpathogenic and provides effective protection to pigs against wild-type ASFV. These results reveal I73R as a virulence-related gene critical for ASFV pathogenesis and suggest that it is a potential target for virus attenuation. Accordingly, the deletion mutant ASFV-GZΔI73R can be a potent live-attenuated vaccine candidate.
Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Virulência/genética , Febre Suína Africana/prevenção & controle , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Genes ViraisRESUMO
Since the first human infection reported in 2013, H7N9 avian influenza virus (AIV) has been regarded as a serious threat to human health. In this study, we sought to identify the virulence determinant of the H7N9 virus in mammalian hosts. By comparing the virulence of the SH/4664 H7N9 virus, a non-virulent H9N2 virus, and various H7N9-H9N2 hybrid viruses in infected mice, we first pinpointed PB2 as the primary viral factor accounting for the difference between H7N9 and H9N2 in mammalian virulence. We further analyzed the in vivo effects of individually mutating H7N9 PB2 residues different from the closely related H9N2 virus and consequently found residue 473, alongside the well-known residue 627, to be critical for the virulence of the H7N9 virus in mice and the activity of its reconstituted viral polymerase in mammalian cells. The importance of PB2-473 was further strengthened by studying reverse H7N9 substitutions in the H9N2 background. Finally, we surprisingly found that species-specific usage of ANP32A, a family member of host factors connecting with the PB2-627 polymorphism, mediates the contribution of PB2 473 residue to the mammalian adaption of AIV polymerase, as the attenuating effect of PB2 M473T on the viral polymerase activity and viral growth of the H7N9 virus could be efficiently complemented by co-expression of chicken ANP32A but not mouse ANP32A and ANP32B. Together, our studies uncovered the PB2 473 residue as a novel viral host range determinant of AIVs via species-specific co-opting of the ANP32 host factor to support viral polymerase activity.IMPORTANCEThe H7N9 avian influenza virus has been considered to have the potential to cause the next pandemic since the first case of human infection reported in 2013. In this study, we identified PB2 residue 473 as a new determinant of mouse virulence and mammalian adaptation of the viral polymerase of the H7N9 virus and its non-pathogenic H9N2 counterparts. We further demonstrated that the variation in PB2-473 is functionally linked to differential co-opting of the host ANP32A protein in supporting viral polymerase activity, which is analogous to the well-known PB2-627 polymorphism, albeit the two PB2 positions are spatially distant. By providing new mechanistic insight into the PB2-mediated host range determination of influenza A viruses, our study implicated the potential existence of multiple PB2-ANP32 interfaces that could be targets for developing new antivirals against the H7N9 virus as well as other mammalian-adapted influenza viruses.
Assuntos
Subtipo H7N9 do Vírus da Influenza A , Influenza Humana , Proteínas Nucleares , Proteínas de Ligação a RNA , Animais , Humanos , Camundongos , Subtipo H7N9 do Vírus da Influenza A/metabolismo , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Vírus da Influenza A Subtipo H9N2 , Influenza Humana/virologia , Mamíferos , Proteínas Nucleares/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas de Ligação a RNA/metabolismo , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Virulência , Replicação ViralRESUMO
Neurodegenerative diseases (NDs) usually connect with aggregation and molecular interactions of pathological proteins. The integration of accumulative data from clinical and biomedical research will allow for the excavation of pathological proteins and related interactors. It is also important to systematically study their interacting proteins in order to find more related proteins and potential therapeutic targets. Understanding binding regions in protein interactions will help functional proteomics and provide an alternative method for predicting novel interactions. This study integrated data from biomedical research to achieve systematic mining and analysis of pathogenic proteins and their interaction network. A workflow has been built as a solution for the collective information of proteins involved in NDs, related protein-protein interactions (PPIs) and interactive visualizations. It also included protein isoforms and mapped them in a disease-related PPI network to illuminate the impact of alternative splicing on protein binding. The interacting proteins enriched by diseases and biological processes (BPs) revealed possible regulatory modules. A high-resolution network with structural affinity information was generated. Finally, Neurodegenerative Disease Atlas (NDAtlas) was constructed with an interactive and intuitive view of protein docking with 3D molecular graphics beyond the traditional 2D network. NDAtlas is available at http://bis.zju.edu.cn/ndatlas.
Assuntos
Doenças Neurodegenerativas , Mapeamento de Interação de Proteínas , Humanos , Ligação Proteica , Mapeamento de Interação de Proteínas/métodos , Doenças Neurodegenerativas/genética , Bases de Dados de Proteínas , Isoformas de Proteínas/genética , Mapas de Interação de ProteínasRESUMO
African swine fever is one of the most serious viral diseases that affects domestic and wild pigs. The causative agent, African swine fever virus (ASFV), has evolved sophisticated immune evasion mechanisms that target both innate and adaptive immune responses. However, the underlying molecular mechanisms have not been fully understood. Here, we report that ASFV E184L protein inhibits host innate immune response via targeting the stimulator of IFN genes (STING)-mediated signaling pathway in both human embryonic kidney HEK-293T cells and porcine pulmonary alveolar macrophages. E184L interacts with STING, impairing dimerization and oligomerization of STING but not affecting its puncta formation at the perinuclear region. Furthermore, E184L disrupts STING-TBK1-IRF3 complex formation, leading to inhibition of STING phosphorylation, and IRF3 dimerization and nuclear translocation. The 1-20 aa region in E184L is essential for E184L-STING interaction and blocking IL-1ß and type I IFN production. Deletion of E184L in ASFV considerably impairs antagonistic function of the virus in suppression of the STING-mediated antiviral response, an effect that is reversible by introduction of E184L. Importantly, the virulence of mutant ASFV lacking E184L is reduced in pigs compared with its parental virus due to induction of higher IFN production in vivo. Our findings indicate that ASFV E184L is an important antagonist of IFN signaling to evade host innate immune antiviral responses, which improves our understanding of immune evasion mechanisms of ASFV.
Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Animais , Humanos , Antivirais/metabolismo , Imunidade Inata , Suínos , Proteínas Virais , Replicação Viral , Proteínas de Membrana/metabolismo , Interferons/biossínteseRESUMO
Giardiasis is a common waterborne zoonotic disease caused by Giardia intestinalis. Upon infection, Giardia releases excretory and secretory products (ESPs) including secreted proteins (SPs) and extracellular vesicles (EVs). Although the interplay between ESPs and intestinal epithelial cells (IECs) has been previously described, the functions of EVs in these interactions and their differences from those of SPs require further exploration. In the present study, EVs and EV-depleted SPs were isolated from Giardia ESPs. Proteomic analyses of isolated SPs and EVs showed 146 and 91 proteins, respectively. Certain unique and enriched proteins have been identified in SPs and EVs. Transcriptome analysis of Caco-2 cells exposed to EVs showed 96 differentially expressed genes (DEGs), with 56 upregulated and 40 downregulated genes. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) indicated that Caco-2 genes related to metabolic processes, the HIF-1 signaling pathway, and the cAMP signaling pathway were affected. This study provides new insights into host-parasite interactions, highlighting the potential significance of EVs on IECs during infections.
Assuntos
Vesículas Extracelulares , Giardia lamblia , Mucosa Intestinal , Humanos , Células CACO-2 , Giardia lamblia/genética , Giardia lamblia/metabolismo , Vesículas Extracelulares/metabolismo , Mucosa Intestinal/parasitologia , Mucosa Intestinal/metabolismo , Perfilação da Expressão Gênica , Células Epiteliais/parasitologia , Células Epiteliais/metabolismo , Proteômica , Interações Hospedeiro-Parasita , Expressão Gênica , Transcriptoma , Giardíase/parasitologiaRESUMO
Bovine gammaherpesvirus 4 (BoHV-4) is a common virus detected in bovine with respiratory disease worldwide. In this study, we identified and characterized a novel BoHV-4 strain, referred as HB-ZJK, in vaginal swabs collected from cattle in China, 2022. The long unique region (LUR) of HB-ZJK is 10,9811 bp in length. It shares 99.17% to 99.38% nucleotide identity to five BoHV-4 strains available in GenBank and the highest similarity was seen with BoHV-4V. test (JN133502.1) strain (99.38%). Mutations, insertions or deletions were observed mainly in HB-ZJK gB (ORF8), TK (ORF21), gH (ORF22), MCP (ORF25), PK (ORF36), gM (ORF39), and gL (ORF47) genes compared to its genomic coordinates. Phylogenetic analyses of gB and TK genes showed that HB-ZJK clustered with China 512 (2019), B6010 (2009), and J4034 (2009) strains, demonstrating that the isolated HB-ZJK belongs to genotype 1. This is the first report that has revealed a comprehensive genome profile of BoHV-4 strain in China. This study will provide foundation for epidemiological investigations of BoHV-4 and contribute to the molecular and pathogenic studies of BoHV-4.
Assuntos
Doenças dos Bovinos , Infecções por Herpesviridae , Herpesvirus Bovino 1 , Herpesvirus Bovino 4 , Feminino , Animais , Bovinos , Filogenia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 4/genética , China , Herpesvirus Bovino 1/genéticaRESUMO
African swine fever virus (ASFV) is highly contagious and can cause lethal disease in pigs. ASFV p72 protein is a major capsid protein that presents as trimer in the virion. Epitopes on the surface of p72 trimer are considered as protective antigens. In this study, recombinant p72 protein and p72-baculovirus were constructed and obtained. Three monoclonal antibodies (mAbs) specific to ASFV p72 protein, designated as 1A3, 2B5 and 4A5, were generated. Among them, 4A5 showed strong reactivity with ASFV infected cells. Subsequently, the epitope recognized by 4A5 was mapped and identified using a series of overlapping peptides generated from p72 protein. IFA and western blot analyses showed that 4A5 recognized the linear epitope of p72 monomer located between amino acids 245-285 and recognized the conformational epitope located at the surface and top of the p72 trimer. These findings will enrich our knowledge regarding the epitope on p72 protein and provide valuable information for further characterization of the antigenicity and molecular functions of p72 protein.
Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Epitopos , Anticorpos Monoclonais , Proteínas do Capsídeo , Proteínas RecombinantesRESUMO
Purpose: Gastrointestinal perforation (GIP) is a fatal adverse event (AE). The AE of GIP induced by novel antineoplastic agents has attracted attention recently. We aimed to explore the AE signals of GIP related to novel antineoplastic agents comprehensively based on the FDA Adverse Event Reporting System (FAERS). Methods: The FAERS database containing 71 quarters of records was used for analysis. Reporting odds ratio (ROR), information component (IC), and empirical Bayesian geometric mean (EBGM) were utilized to evaluate the signals of GIP associated with novel antineoplastic drugs. Standardization of drug names was by employing MedEx-UIMA software and Python. Data analysis and visualization were performed using MySQL Workbench and R software. Results: After cleaning and handling the data, 5226 GIP cases were identified that were associated with new antineoplastic medications, where these agents were the main suspected contributors. A total of 37 novel antineoplastic drugs were detected with signals of GIP for ROR and IC. Only 22 drugs showed statistically significant signals for EBGM. We found the GIP signals of 22 novel antineoplastic drugs overlapped for the 3 indicators, including anti-vascular endothelial growth factor/vascular endothelial growth factor receptor, anti-endothelial growth factor receptor, immune checkpoint inhibitors, and so on. Conclusion: The potential risk of GIP associated with several novel antineoplastic agents was identified through data mining, which provided valuable information on the safety risks associated with GIP among these drugs. The potential threat of GIP should be recognized and managed properly when using these novel antineoplastic agents.
Assuntos
Antineoplásicos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Estados Unidos , Humanos , Sistemas de Notificação de Reações Adversas a Medicamentos , Teorema de Bayes , United States Food and Drug Administration , Software , Antineoplásicos/efeitos adversosRESUMO
BACKGROUND: The expression and biological functions of circular RNAs (circRNAs) in reproductive organs have been extensively reported. However, it is still unclear whether circRNAs are involved in sex change. To this end, RNA sequencing (RNA-seq) was performed in gonads at 5 sexual stages (ovary, early intersexual stage gonad, middle intersexual stage gonad, late intersexual stage gonad, and testis) of ricefield eel, and the expression profiles and potential functions of circRNAs were studied. RESULTS: Seven hundred twenty-one circRNAs were identified, and the expression levels of 10 circRNAs were verified by quantitative real-time PCR (qRT-PCR) and found to be in accordance with the RNA-seq data, suggesting that the RNA-seq data were reliable. Then, the sequence length, category, sequence composition and the relationship between the parent genes of the circRNAs were explored. A total of 147 circRNAs were differentially expressed in the sex change process, and GO and KEGG analyses revealed that some differentially expressed (such as novel_circ_0000659, novel_circ_0004005 and novel_circ_0005865) circRNAs were closely involved in sex change. Furthermore, expression pattern analysis demonstrated that both circSnd1 and foxl2 were downregulated in the process of sex change, which was contrary to mal-miR-135b. Finally, dual-luciferase reporter assay and RNA immunoprecipitation showed that circSnd1 and foxl2 can combine with mal-miR-135b and mal-miR-135c. These data revealed that circSnd1 regulates foxl2 expression in the sex change of ricefield eel by acting as a sponge of mal-miR-135b/c. CONCLUSION: Our results are the first to demonstrate that circRNAs have potential effects on sex change in ricefield eel; and circSnd1 could regulate foxl2 expression in the sex change of ricefield eel by acting as a sponge of mal-miR-135b/c. These data will be useful for enhancing our understanding of sequential hermaphroditism and sex change in ricefield eel or other teleosts.
Assuntos
Transtornos do Desenvolvimento Sexual , MicroRNAs , Smegmamorpha , Animais , Enguias/genética , Feminino , Gônadas , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , Smegmamorpha/genéticaRESUMO
BACKGROUND: An increasing number of long noncoding RNAs (lncRNAs) have been found to play important roles in sex differentiation and gonad development by regulating gene expression at the epigenetic, transcriptional and posttranscriptional levels. The ricefield eel, Monopterus albus, is a protogynous hermaphroditic fish that undergoes a sequential sex change from female to male. However, the roles of lncRNA in the sex change is unclear. RESULTS: Herein, we performed RNA sequencing to analyse lncRNA expression patterns in five different stages of M. albus development to investigate the roles of lncRNAs in the sex change process. A total of 12,746 lncRNAs (1503 known lncRNAs and 11,243 new lncRNAs) and 2901 differentially expressed lncRNAs (DE-lncRNAs) were identified in the gonads. The target genes of the DE-lncRNAs included foxo1, foxm1, smad3, foxr1, camk4, ar and tgfb3, which were mainly enriched in signalling pathways related to gonadal development, such as the insulin signalling pathway, MAPK signalling pathway, and calcium signalling pathway. We selected 5 highly expressed DE-lncRNAs (LOC109952131, LOC109953466, LOC109954337, LOC109954360 and LOC109958454) for full length amplification and expression pattern verification. They were all expressed at higher levels in ovaries and intersex gonads than in testes, and exhibited specific time-dependent expression in ovarian tissue incubated with follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG). The results of quantitative real-time PCR (qRT-PCR) analysis and a dual-luciferase assay showed that znf207, as the gene targeted by LOC109958454, was expressed in multiple tissues and gonadal developmental stages of M. albus, and its expression was also inhibited by the hormones FSH and hCG. CONCLUSIONS: These results provide new insights into the role of lncRNAs in gonad development, especially regarding natural sex changes in fish, which will be useful for enhancing our understanding of sequential hermaphroditism and sex changes in the ricefield eel (M. albus) and other teleosts.
Assuntos
Transtornos do Desenvolvimento Sexual , RNA Longo não Codificante , Smegmamorpha , Animais , Enguias/genética , Feminino , Hormônio Foliculoestimulante/metabolismo , Gônadas , Masculino , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Smegmamorpha/genéticaRESUMO
Research of protein-protein interaction in several model organisms is accumulating since the development of high-throughput experimental technologies and computational methods. The protein-protein interaction network (PPIN) is able to examine biological processes in a systematic manner and has already been used to predict potential disease-related proteins or drug targets. Based on the topological characteristics of the PPIN, we investigated the application of the random forest classification algorithm to predict proteins that may cause neurodegenerative disease, a set of pathological changes featured by protein malfunction. By integrating multiomics data, we further showed the validity of our machine learning model and narrowed down the prediction results to several hub proteins that play essential roles in the PPIN. The novel insights into neurodegeneration pathogenesis brought by this computational study can indicate promising directions for future experimental research.
Assuntos
Terapia de Alvo Molecular , Doenças Neurodegenerativas/genética , Mapas de Interação de Proteínas/genética , Proteínas/genética , Algoritmos , Biologia Computacional , Humanos , Aprendizado de Máquina , Doenças Neurodegenerativas/terapia , Proteínas/antagonistas & inibidores , Proteoma/genética , Transcriptoma/genéticaRESUMO
BACKGROUND: WRKY transcription factors (TFs) play vital roles in plant growth and development, secondary metabolite synthesis, and response to biotic and abiotic stresses. In a previous transcriptome sequencing analysis of Lilium regale Wilson, we identified multiple WRKY TFs that respond to exogenous methyl jasmonate treatment and lily Fusarium wilt (Fusarium oxysporum). RESULTS: In the present study, the WRKY TF LrWRKY3 was further analyzed to reveal its function in defense response to F. oxysporum. The LrWRKY3 protein was localized in the plant cell nucleus, and LrWRKY3 transgenic tobacco lines showed higher resistance to F. oxysporum compared with wild-type (WT) tobacco. In addition, some genes related to jasmonic acid (JA) biosynthesis, salicylic acid (SA) signal transduction, and disease resistance had higher transcriptional levels in the LrWRKY3 transgenic tobacco lines than in the WT. On the contrary, L. regale scales transiently expressing LrWRKY3 RNA interference fragments showed higher sensitivity to F. oxysporum infection. Moreover, a F. oxysporum-induced defensin gene, Def1, was isolated from L. regale, and the recombinant protein LrDef1 isolated and purified from Escherichia coli possessed antifungal activity to several phytopathogens, including F. oxysporum. Furthermore, co-expression of LrWRKY3 and the LrDef1 promoter in tobacco enhanced the LrDef1 promoter-driven expression activity. CONCLUSIONS: These results clearly indicate that LrWRKY3 is an important positive regulator in response to F. oxysporum infection, and one of its targets is the antimicrobial peptide gene LrDef1.
Assuntos
Fusarium , Lilium , Peptídeos Antimicrobianos , Fusarium/fisiologia , Regulação da Expressão Gênica de Plantas , Lilium/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologiaRESUMO
African swine fever virus (ASFV) is one of the most contagious and lethal viruses infecting pigs. This virus is endemic in many countries and has very recently spread to China, but no licensed vaccines or treatments are currently available. Despite extensive research, the basic question of how ASFV-encoded proteins inhibit host translation remains. Here, we examined how ASFV interfered with host translation and optimized viral gene expression. We found that 14 ASFV proteins inhibited Renilla luciferase (Rluc) activity greater than 5-fold, and the protein with the strongest inhibitory effect was pE66L, which was not previously reported. Combined with bioinformatical analysis and biochemical experiment, we determined that the transmembrane (TM) domain (amino acids 13-34) of pE66L was required for the inhibition of host gene expression. Notably, we constructed a recombinant plasmid with the TM domain linked to enhanced green fluorescent protein (EGFP) and further demonstrated that this domain broadly inhibited protein synthesis. Confocal and biochemical analyses indicated that the TM domain might help proteins locate to the endoplasmic reticulum (ER) to suppress translation though the PKR/eIF2α pathway. Deletion of the E66L gene had little effect on virus replication in macrophages, but significantly recovered host gene expression. Taken together, our findings complement studies on the host translation of ASFV proteins and suggest that ASFV pE66L induces host translation shutoff, which is dependent on activation of the PKR/eIF2α pathway.Importance African swine fever virus (ASFV) is a member of the nucleocytoplasmic large DNA virus superfamily that predominantly replicates in the cytoplasm of infected cells. The ASFV double-stranded DNA genome varies in length from approximately 170 to 193 kbp depending on the isolate and contains between 150 and 167 open reading frames (ORFs), of which half the encoded proteins have not been explored. Our study showed that 14 proteins had an obvious inhibitory effect on Renilla luciferase (Rluc) gene synthesis, with pE66L showing the most significant effect. Furthermore, the transmembrane (TM) domain of pE66L broadly inhibited host protein synthesis in a PKR/eIF2a pathway-dependent manner. Loss of pE66L during ASFV infection had little effect on virus replication, but significantly recovered host protein synthetic. Based on the above results, our findings expand our view of ASFV in determining the fate of host-pathogen interactions.
RESUMO
Based on our previous studies, we show that the M gene is critical for the replication and pathogenicity of the chimeric H17 bat influenza virus (Bat09:mH1mN1) by replacing the bat M gene with those from human and swine influenza A viruses. However, the key amino acids of the M1 and/or M2 proteins that are responsible for virus replication and pathogenicity remain unknown. In this study, replacement of the PR8 M gene with the Eurasian avian-like M gene from the A/California/04/2009 pandemic H1N1 virus significantly decreased viral replication in both mammalian and avian cells in the background of the chimeric H17 bat influenza virus. Further studies revealed that M1 was more crucial for viral growth and pathogenicity than M2 and that the amino acid residues M1-41V and M2-27A were responsible for these characteristics in cells and in mice. These key residues of the M1 and M2 proteins identified in this study might be important for influenza virus surveillance and could be used to produce live attenuated vaccines in the future. IMPORTANCE The M1 and M2 proteins influence the morphology, replication, virulence, and transmissibility of influenza viruses. Although a few key residues in the M1 and M2 proteins have been identified, whether other residues of the M1 and M2 proteins are involved in viral replication and pathogenicity remains to be discovered. In the background of the chimeric H17 bat influenza virus, the Eurasian avian-like M gene from the A/California/04/2009 virus significantly decreased viral growth in mammalian and avian cells. Further study showed that M1 was implicated more than M2 in viral growth and pathogenicity in vitro and in vivo and that the key amino acid residues M1-41V and M2-27A were responsible for these characteristics in cells and in mice. These key residues of the M1 and M2 proteins could be used for influenza virus surveillance and live attenuated vaccine applications in the future. These findings provide important contributions to knowledge of the genetic basis of the virulence of influenza viruses.
Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Infecções por Orthomyxoviridae/virologia , Orthomyxoviridae/crescimento & desenvolvimento , Orthomyxoviridae/patogenicidade , Proteínas da Matriz Viral/metabolismo , Aminoácidos/metabolismo , Animais , Linhagem Celular , Quirópteros , Genes Virais , Humanos , Pulmão/virologia , Camundongos , Orthomyxoviridae/genética , Vírus Reordenados/genética , Vírus Reordenados/crescimento & desenvolvimento , Vírus Reordenados/patogenicidade , Conchas Nasais/virologia , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/genética , Virulência , Replicação ViralRESUMO
African swine fever is a devastating disease of swine caused by African swine fever virus (ASFV). The pathogenesis of the disease remains largely unknown, leaving the spread of the disease uncontrolled in many countries and regions. Here, we identified E120R, a structural protein of ASFV, as a key virulence factor and late-phase-expressed protein of the virus. E120R revealed an activity to suppress the host antiviral response through blocking beta interferon (IFN-ß) production, and the amino acids (aa) at sites 72 and 73 (amino acids 72-73) in the C-terminal domain were essential for this function. E120R interacted with interferon regulatory factor 3 (IRF3) and interfered with the recruitment of IRF3 to TANK-binding kinase 1 (TBK1), which in turn suppressed IRF3 phosphorylation, decreasing interferon production. A recombinant mutant ASFV was further constructed to confirm the claimed mechanism. The ASFV lacking the complete E120R region could not be rescued, whereas the virus could tolerate the deletion of the 72nd and 73rd residues in E120R (ASFV E120R-Δ72-73aa). ASFV E120R with the two-amino-acid deletion failed to interact with IRF3 during ASFV E120R-Δ72-73aa infection, and the viral infection activated IRF3 phosphorylation highly and induced more robust type I interferon production than its parental ASFV. An unbiased transcriptome-wide analysis of gene expression also confirmed that considerably more IFN-stimulated genes (ISGs) were detected in ASFV E120R-Δ72-73aa-infected porcine alveolar macrophages (PAMs) than in wild-type ASFV-infected PAMs. Together, our findings have identified a novel mechanism evolved by ASFV to inhibit the host antiviral response, and they provide a new target for guiding the development of ASFV live-attenuated vaccine. IMPORTANCE African swine fever is a highly contagious animal disease affecting the pig industry worldwide, which has brought enormous economic losses. Infection by the causative agent, African swine fever virus (ASFV), causes severe immunosuppression during viral infection, contributing to serious clinical manifestations. Therefore, identification of the viral proteins involved in immunosuppression is critical for ASFV vaccine design and development. Here, for the first time, we demonstrated that E120R protein, a structural protein of ASFV, played an important role in suppression of interferon regulatory factor 3 (IRF3) phosphorylation and type I interferon production by binding to IRF3 and blocking the recruitment of IRF3 to TANK-binding kinase 1 (TBK1). Deletion of the crucial binding sites in E120R critically increased the interferon response during ASFV infection. This study explored a novel antagonistic mechanism of ASFV, which is critical for guiding the development of ASFV live-attenuated vaccines.
Assuntos
Vírus da Febre Suína Africana/fisiologia , Febre Suína Africana/virologia , Interações Hospedeiro-Patógeno , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/metabolismo , Mutação , Proteínas Virais/metabolismo , Febre Suína Africana/genética , Febre Suína Africana/metabolismo , Animais , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/genética , Fosforilação , Transdução de Sinais , Suínos , Proteínas Virais/genética , VirulênciaRESUMO
Root rot of Panax notoginseng, a precious Chinese medicinal plant, seriously impacts its sustainable production. However, the molecular regulatory mechanisms employed by P. notoginseng against root rot pathogens, including Fusarium solani, are still unclear. In this study, the PnMYB2 gene was isolated, and its expression was affected by independent treatments with four signaling molecules (methyl jasmonate, ethephon, salicylic acid, and hydrogen peroxide) as assessed by quantitative real-time PCR. Moreover, the PnMYB2 expression level was induced by F. solani infection. The PnMYB2 protein localized to the nucleus and may function as a transcription factor. When overexpressed in transgenic tobacco, the PnMYB2 gene conferred resistance to F. solani. Jasmonic acid (JA) metabolism and disease resistance-related genes were induced in the transgenic tobacco, and the JA content significantly increased compared with in the wild type. Additionally, transcriptome sequencing, Kyoto Encyclopedia of Genes and Genomes annotation enrichment, and metabolic pathway analyses of the differentially expressed genes in the transgenic tobacco revealed that JA metabolic, photosynthetic, and defense response-related pathways were activated. In summary, PnMYB2 is an important transcription factor in the defense responses of P. notoginseng against root rot pathogens that acts by regulating JA signaling, photosynthesis, and disease-resistance genes.
Assuntos
Fusarium , Panax notoginseng , Ciclopentanos , Resistência à Doença/genética , Fusarium/metabolismo , Oxilipinas , Panax notoginseng/genética , Panax notoginseng/metabolismo , Fotossíntese , Doenças das Plantas/genética , Transdução de Sinais , Nicotiana/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
This study aims to examine the relative contributions of phonological awareness (PA), orthographical awareness (OA), morphological awareness (MA) and rapid automatized naming (RAN) to word reading accuracy and fluency in Chinese deaf and hard of hearing (DHH) students. Measures of PA, OA, MA, RAN, word reading accuracy, and word reading fluency were administered to 133 DHH and 127 hearing students in Grades 4-6. After controlling for chronological age, hierarchical regression analysis showed that PA made an independent contribution to word reading accuracy and fluency among the DHH students. The unique effect of OA was significant on word reading accuracy in DHH students; whereas, its predictive role was played on word reading fluency in hearing students. RAN accounted for additional variance only in word reading accuracy in DHH students. MA significantly explained the variance in both reading abilities and in both groups. This suggests that for DHH students, they use nonphonological clues (MA and OA) to learn to read. To a lesser degree, however, they do rely on PA to reading words. For hearing students, they mainly rely on MA to their word reading. There are some similarities and differences in the mechanisms underlying word reading in DHH and hearing children.
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Pessoas com Deficiência Auditiva , Leitura , Conscientização , Criança , Surdez , Humanos , FonéticaRESUMO
Nowadays, the main obstacle for further miniaturization and integration of nucleic acids point-of-care testing devices is the lack of low-cost and high-performance heating materials for supporting reliable nucleic acids amplification. Herein, reduced graphene oxide hybridized multi-walled carbon nanotubes nano-circuit integrated into an ingenious paper-based heater is developed, which is integrated into a paper-based analytical device (named HiPAD). The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still raging across the world. As a proof of concept, the HiPAD is utilized to visually detect the SARS-CoV-2 N gene using colored loop-mediated isothermal amplification reaction. This HiPAD costing a few dollars has comparable detection performance to traditional nucleic acids amplifier costing thousands of dollars. The detection range is from 25 to 2.5 × 1010 copies mL-1 in 45 min. The detection limit of 25 copies mL-1 is 40 times more sensitive than 1000 copies mL-1 in conventional real-time PCR instruments. The disposable paper-based chip could also avoid potential secondary transmission of COVID-19 by convenient incineration to guarantee biosafety. The HiPAD or easily expanded M-HiPAD (for multiplex detection) has great potential for pathogen diagnostics in resource-limited settings.
RESUMO
Recently, the disease of hepatitis-hydropericardium syndrome (HPS) caused by serotype 4 fowl adenovirus (FAdV-4) has spread widely and resulted in huge economic losses to the poultry industry. Although the genome of FAdV-4 has two fiber genes (fiber-1 and fiber-2), the exact role of the genes in the infection of FAdV-4 is barely known. In this study, through superinfection resistance analysis and an interfering assay, we found that fiber-1, but not fiber-2, was the key factor for directly triggering the infection of FAdV-4. The truncation analysis further revealed that both of the shaft and knob domains of fiber-1 were required for the infection. Moreover, the sera against the knob domain were able to block FAdV-4 infection, and the knob-containing fusion protein provided efficient protection against the lethal challenge of FAdV-4 in chickens. All the data demonstrated the significant roles of fiber-1 and its knob domain in directly mediating the infection of FAdV-4, which established a foundation for identifying the receptor of FAdV-4 and developing efficient vaccines against FAdV-4.IMPORTANCE Among 12 serotypes of fowl adenovirus (FAdV), FAdV-1, FAdV-4, and FAdV-10 all carry two fiber genes (i.e., fiber-1 and fiber-2), whereas other serotypes have only one. As important viral surface proteins, the fibers play vital roles in the infection and pathogenesis of FAdV. However, the importance of the fibers to the infection and pathogenesis of FAdV may be different from each other. Recent studies reveal that fiber-2 is identified as a determinant of virulence, but which fiber triggers the infection of FAdV-4 remains unknown. In this study, fiber-1 was identified as a key factor for directly mediating the infection of FAdV-4 through its shaft and knob domains, whereas fiber-2 did not play a role in triggering FAdV-4 infection. The results suggest that fiber-1 and its knob domain may serve as a target for identifying the receptor of FAdV-4 and developing efficient drugs or vaccines against FAdV-4.
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Infecções por Adenoviridae/virologia , Adenoviridae/genética , Adenoviridae/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Doenças das Aves Domésticas/virologia , Adenoviridae/patogenicidade , Infecções por Adenoviridae/imunologia , Infecções por Adenoviridae/patologia , Infecções por Adenoviridae/prevenção & controle , Animais , Anticorpos Antivirais , Linhagem Celular , Galinhas/virologia , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/prevenção & controle , Domínios Proteicos , Sorogrupo , Vacinas Virais/imunologiaRESUMO
Previous studies have shown that chimeric bat influenza viruses can be generated by reverse genetic system. However, the roles of the surface or internal genes of chimeric bat influenza viruses in viral replication and virulence in different host species were still not completely understood. In this study, we generated a chimeric H9N2 bat virus with both HA and NA surface genes from the avian A2093/H9N2 virus and compared its replication and virulence with the chimeric H1N1 bat virus with both HA and NA from the PR8/H1N1 virus in vitro and in mice. The chimeric H1N1 virus showed significantly higher replication in mammalian and avian cells and significantly higher virulence in mice than the chimeric H9N2 virus. Moreover, the chimeric H9N2 virus with the bat influenza internal M gene showed a higher replication in mammalian cells than in avian cells. While the chimeric H9N2 virus with the avian-origin viral M gene displayed a higher replication than that with the bat influenza M gene in avian cells, which likely resulted from increased receptor binding ability to α 2,3 sialic acid linked glycans of the former virus. Our study indicates that bat influenza internal genes are permissive in both mammalian and avian cells, and the bat influenza internal M gene shows more compatibility in mammals than in the avian host. Although the surface genes play more critical roles for viral replication in different host substrates, influenza M gene also potentially impacts on replication, virulence and host tropism.