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1.
J Virol ; 98(3): e0185923, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38411948

RESUMO

Superinfection exclusion (SIE) is a phenomenon in which a preexisting infection prevents a secondary infection. SIE has been described for several flaviviruses, such as West Nile virus vs Nhumirim virus and Dengue virus vs yellow fever virus. Zika virus (ZIKV) is an emerging flavivirus posing threats to human health. The SIE between ZIKV and Japanese encephalitis virus (JEV) is investigated in this study. Our results demonstrate for the first time that JEV inhibits ZIKV infection in both mammalian and mosquito cells, whether co-infects or subsequently infects after ZIKV. The exclusion effect happens at the stage of ZIKV RNA replication. Further studies show that the expression of JEV NS2B protein is sufficient to inhibit the replication of ZIKV, and the outer membrane region of NS2B (46-103 aa) is responsible for this SIE. JEV infection and NS2B expression also inhibit the infection of the vesicular stomatitis virus. In summary, our study characterized a SIE caused by JEV NS2B. This may have potential applications in the prevention and treatment of ZIKV or other RNA viruses.IMPORTANCEThe reemerged Zika virus (ZIKV) has caused severe symptoms in humans and poses a continuous threat to public health. New vaccines or antiviral agents need to be developed to cope with possible future pandemics. In this study, we found that infection of Japanese encephalitis virus (JEV) or expression of NS2B protein well inhibited the replication of ZIKV. It is worth noting that both the P3 strain and vaccine strain SA14-14-2 of JEV exhibited significant inhibitory effects on ZIKV. Additionally, the JEV NS2B protein also had an inhibitory effect on vesicular stomatitis virus infection, suggesting that it may be a broad-spectrum antiviral factor. These findings provide a new way of thinking about the prevention and treatment of ZIKV.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Superinfecção , Proteínas não Estruturais Virais , Infecção por Zika virus , Animais , Humanos , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/metabolismo , Encefalite Japonesa/virologia , Estomatite Vesicular , Zika virus , Proteínas não Estruturais Virais/metabolismo
2.
J Virol ; 98(9): e0079624, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39115433

RESUMO

Host cells have evolved an intricate regulatory network to fine tune the type-I interferon responses. However, the full picture of this regulatory network remains to be depicted. In this study, we found that knock out of zinc-finger CCHC-type containing protein 8 (ZCCHC8) impairs the replication of influenza A virus (IAV), Sendai virus (Sev), Japanese encephalitis virus (JEV), and vesicular stomatitis virus (VSV). Further investigation unveiled that ZCCHC8 suppresses the type-I interferon responses by targeting the interferon regulatory factor 3 (IRF3) signaling pathway. Mechanistically, ZCCHC8 associates with phosphorylated IRF3 and disrupts the interaction of IRF3 with the co-activator CREB-binding protein (CBP). Additionally, the direct binding of ZCCHC8 with the IFN-stimulated response element (ISRE) impairs the ISRE-binding of IRF3. Our study contributes to the comprehensive understanding for the negative regulatory network of the type-I interferon responses and provides valuable insights for the control of multiple viruses from a host-centric perspective.IMPORTANCEThe innate immune responses serve as the initial line of defense against invading pathogens and harmful substances. Negative regulation of the innate immune responses plays an essential role in avoiding auto-immune diseases and over-activated immune responses. Hence, the comprehensive understanding of the negative regulation network for innate immune responses could provide novel therapeutic insights for the control of viral infections and immune dysfunction. In this study, we report that ZCCHC8 negatively regulates the type-I interferon responses. We illustrate that ZCCHC8 impedes the IRF3-CBP association by interacting with phosphorylated IRF3 and competes with IRF3 for binding to ISRE. Our study demonstrates the role of ZCCHC8 in the replication of multiple RNA viruses and contributes to a deeper understanding of the negative regulation system for the type-I interferon responses.


Assuntos
Proteína de Ligação a CREB , Imunidade Inata , Fator Regulador 3 de Interferon , Interferon Tipo I , Vírus Sendai , Transdução de Sinais , Replicação Viral , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Humanos , Células HEK293 , Vírus Sendai/fisiologia , Vírus Sendai/genética , Proteína de Ligação a CREB/metabolismo , Proteína de Ligação a CREB/genética , Vírus de RNA/fisiologia , Vírus de RNA/imunologia , Vírus de RNA/genética , Animais , Células A549 , Vírus da Influenza A/fisiologia , Vírus da Influenza A/imunologia , Fosforilação , Interações Hospedeiro-Patógeno , Vesiculovirus/fisiologia , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Vírus da Encefalite Japonesa (Espécie)/imunologia
3.
PLoS Pathog ; 19(4): e1011305, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37053288

RESUMO

N6-methyladenosine (m6A) modification on viral RNAs has a profound impact on infectivity. m6A is also a highly pervasive modification for influenza viral RNAs. However, its role in virus mRNA splicing is largely unknown. Here, we identify the m6A reader protein YTHDC1 as a host factor that associates with influenza A virus NS1 protein and modulates viral mRNA splicing. YTHDC1 levels are enhanced by IAV infection. We demonstrate that YTHDC1 inhibits NS splicing by binding to an NS 3' splicing site and promotes IAV replication and pathogenicity in vitro and in vivo. Our results provide a mechanistic understanding of IAV-host interactions, a potential therapeutic target for blocking influenza virus infection, and a new avenue for the development of attenuated vaccines.


Assuntos
Vírus da Influenza A , Influenza Humana , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/metabolismo , Influenza Humana/genética , Replicação Viral/genética , RNA Mensageiro/genética , Fatores de Processamento de RNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo
4.
Rev Med Virol ; 34(3): e2539, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719789

RESUMO

The viral infection of the central nervous system is a significant public health concern. So far, most clinical cases of viral neuroinvasion are dealt with supportive and/or symptomatic treatments due to the unavailability of specific treatments. Thus, developing specific therapies is required to alleviate neurological symptoms and disorders. In this review, we shed light on molecular aspects of viruses' entry into the brain which upon targeting with specific drugs have shown promising efficacy in vitro and in preclinical in vivo model systems. Further assessing the therapeutic potential of these drugs in clinical trials may offer opportunities to halt viral neuroinvasion in humans.


Assuntos
Antivirais , Humanos , Animais , Antivirais/uso terapêutico , Antivirais/farmacologia , Internalização do Vírus/efeitos dos fármacos , Encéfalo/virologia , Encéfalo/patologia , Encéfalo/efeitos dos fármacos , Viroses do Sistema Nervoso Central/tratamento farmacológico , Viroses do Sistema Nervoso Central/virologia
6.
J Gen Virol ; 105(4)2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38656455

RESUMO

Porcine epidemic diarrhea (PED) is a serious disease in piglets that leads to high mortality. An effective measure that provides higher IgA levels in the intestine and milk is required to decrease losses. Porcine epidemic diarrhea virus (PEDV) was dissolved in calcium alginate (Alg) and combined with chitosan (CS) via electrostatic interactions between cationic chitosan and anionic alginate to create a porous gel (Alg-CS+PEDV). The gel was used to immunize mice orally or in combination with subcutaneous injections of inactivated PEDV vaccine. At 12 and 24 days after immunization, levels of IgA and IgG in Alg-CS+PEDV were higher than with normal PEDV oral administration. At 24 days after immunization, the concentration of IFN-γ in Alg-CS+PEDV was higher than with normal PEDV oral administration. Furthermore, oral administration combining subcutaneous immunization induced higher levels of IgG and IgA than oral administration alone. Our study provides a new method for the preparation and administration of oral vaccines to achieve enhanced mucosal immunity against PEDV.


Assuntos
Alginatos , Anticorpos Antivirais , Quitosana , Imunidade nas Mucosas , Imunoglobulina A , Imunoglobulina G , Vírus da Diarreia Epidêmica Suína , Vacinas Virais , Animais , Administração Oral , Vírus da Diarreia Epidêmica Suína/imunologia , Alginatos/administração & dosagem , Quitosana/administração & dosagem , Camundongos , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Anticorpos Antivirais/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Suínos , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Feminino , Géis/administração & dosagem , Camundongos Endogâmicos BALB C , Interferon gama/imunologia , Ácido Glucurônico/administração & dosagem , Ácidos Hexurônicos/administração & dosagem
7.
J Gen Virol ; 105(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506716

RESUMO

PCV2 belongs to the genus Circovirus in the family Circoviridae, whose genome is replicated by rolling circle replication (RCR). PCV2 Rep is a multifunctional enzyme that performs essential functions at multiple stages of viral replication. Rep is responsible for nicking and ligating single-stranded DNA and unwinding double-stranded DNA (dsDNA). However, the structure and function of the Rep are still poorly understood, which significantly impedes viral replication research. This study successfully resolved the structure of the PCV2 Rep ATPase domain (PRAD) using X-ray crystallography. Homologous structure search revealed that Rep belonged to the superfamily 3 (SF3) helicase, and multiple conserved residues were identified during sequence alignment with SF3 family members. Simultaneously, a hexameric PRAD model was generated for analysing characteristic structures and sites. Mutation of the conserved site and measurement of its activity showed that the hallmark motifs of the SF3 family influenced helicase activity by affecting ATPase activity and ß-hairpin just caused the loss of helicase activity. The structural and functional analyses of the PRAD provide valuable insights for future research on PCV2 replication and antiviral strategies.


Assuntos
Circovirus , Suínos , Animais , Circovirus/genética , Adenosina Trifosfatases/genética , Cristalografia por Raios X , DNA Helicases/genética , Replicação do DNA
8.
BMC Biotechnol ; 24(1): 60, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227838

RESUMO

BACKGROUND: Glaesserella parasuis (G. parasuis) is the causative agent of Glässer's disease, which causes significant economic losses in the swine industry. However, research on the pathogenesis of G. parasuis has been hampered by the lack of a simple and efficient marker-free knockout system. RESULTS: In this study, a marker-free knockout system was developed for G. parasuis using a temperature-sensitive vector. By alternating the incubation of transformants at 30°C and 37°C, we optimized the screening process for this system. The system was successfully applied to knockout the KanR cassette from JS0135ΔnanH::KanR, achieving a knockout efficiency of 90% in the final round of screening. To confirm that temperature variation was a key factor, we proceeded with knocking out the nanH and apd genes in the CF7066 strain. The knockout efficiency reached up to 100%, with the shortest screening time being only four days. The knockout of the nanH gene resulted in a significant reduction in the growth vitality of the strains, while the knockout of the apd gene led to an approximate 56% improvement in the adhesion rate. Additionally, we observed that the expression of recombinant genes in transformants was higher at 30℃ than at 37℃, with the recC gene being upregulated approximately 7-fold. In contrast, there was almost no difference in the expression of recombinant genes between 30℃ and 37℃ in the wild-type strains. This discrepancy was likely due to an elevated copy number of target plasmids at 30℃, which may have resulted in the enhanced expression of recombinant genes. CONCLUSIONS: In conclusion, this newly developed gene knockout system for G. parasuis presents a valuable tool for advancing research on this organism.


Assuntos
Técnicas de Inativação de Genes , Haemophilus parasuis , Temperatura , Haemophilus parasuis/genética , Técnicas de Inativação de Genes/métodos , Animais , Suínos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
9.
J Neuroinflammation ; 21(1): 76, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532383

RESUMO

Japanese encephalitis virus (JEV) is a neurotropic pathogen that causes lethal encephalitis. The high susceptibility and massive proliferation of JEV in neurons lead to extensive neuronal damage and inflammation within the central nervous system. Despite extensive research on JEV pathogenesis, the effect of JEV on the cellular composition and viral tropism towards distinct neuronal subtypes in the brain is still not well comprehended. To address these issues, we performed single-cell RNA sequencing (scRNA-seq) on cells isolated from the JEV-highly infected regions of mouse brain. We obtained 88,000 single cells and identified 34 clusters representing 10 major cell types. The scRNA-seq results revealed an increasing amount of activated microglia cells and infiltrating immune cells, including monocytes & macrophages, T cells, and natural killer cells, which were associated with the severity of symptoms. Additionally, we observed enhanced communication between individual cells and significant ligand-receptor pairs related to tight junctions, chemokines and antigen-presenting molecules upon JEV infection, suggesting an upregulation of endothelial permeability, inflammation and antiviral response. Moreover, we identified that Baiap2-positive neurons were highly susceptible to JEV. Our findings provide valuable clues for understanding the mechanism of JEV induced neuro-damage and inflammation as well as developing therapies for Japanese encephalitis.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Vírus da Encefalite Japonesa (Subgrupo) , Encefalite Japonesa , Camundongos , Animais , Tropismo Viral , Sistema Nervoso Central/patologia , Encefalite Japonesa/patologia , Inflamação , Análise de Sequência de RNA
10.
J Virol ; 97(10): e0092623, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37754758

RESUMO

IMPORTANCE: Type I interferon (IFN-I), produced by the innate immune system, plays an essential role in host antiviral responses. Proper regulation of IFN-I production is required for the host to balance immune responses and prevent superfluous inflammation. IFN regulatory factor 3 (IRF3) and subsequent sensors are activated by RNA virus infection to induce IFN-I production. Therefore, proper regulation of IRF3 serves as an important way to control innate immunity and viral replication. Here, we first identified Prohibitin1 (PHB1) as a negative regulator of host IFN-I innate immune responses. Mechanistically, PHB1 inhibited the nucleus import of IRF3 by impairing its binding with importin subunit alpha-1 and importin subunit alpha-5. Our study demonstrates the mechanism by which PHB1 facilitates the replication of multiple RNA viruses and provides insights into the negative regulation of host immune responses.


Assuntos
Proteína DEAD-box 58 , Proibitinas , Vírus de RNA , Receptores Imunológicos , Transdução de Sinais , Replicação Viral , Proteína DEAD-box 58/antagonistas & inibidores , Proteína DEAD-box 58/metabolismo , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Carioferinas/metabolismo , Proibitinas/metabolismo , Receptores Imunológicos/antagonistas & inibidores , Receptores Imunológicos/metabolismo , Interferon Tipo I/biossíntese , Interferon Tipo I/imunologia , Vírus de RNA/crescimento & desenvolvimento , Vírus de RNA/imunologia , Vírus de RNA/metabolismo
11.
J Virol ; 97(5): e0045923, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37097154

RESUMO

Numerous studies have illustrated that the Seneca Valley virus (SVV) shows sufficient oncolytic efficacy targeting small cell lung cancer (SCLC). However, the therapeutics of nonsmall cell lung carcinoma (NSCLC, accounts for 85% of lung cancer cases) using oncolytic virus have been resisting due to the filtration of neutralizing antibody and limited reproduction capacity. Here, we employed structural biology and reverse genetics to optimize novel oncolytic SVV mutants (viral receptor-associated mutant SVV-S177A and viral antigenic peptide-related variant SVV-S177A/P60S) with increased infectivity and lower immunogenicity. The results of the NSCLC-bearing athymic mouse model demonstrated that wild-type (wt) SVV-HB extended the median overall survival (mOS) from 11 days in the PBS group to 19 days. Notably, the newly discovered mutations significantly (P < 0.001) prolonged the mOS from 11 days in the control cohort to 23 days in the SVV-S177A cohort and the SVV-S177A/P60S cohort. Taken together, we present a structure-guided genetic modification strategy for oncolytic SVV optimization and provide a candidate for developing oncolytic viral therapy against nonsensitive NSCLC. IMPORTANCE Nonsmall cell lung cancer (NSCLC) accounts for approximately 85% of lung cancer cases (more than 1.85 million cases with 1.48 million deaths in 2020). In the present study, two novel oncolytic SVV mutants modified based on structural biology and reverse genetics (viral receptor-associated mutant SVV-S177A and viral antigenic peptide-related mutant SVV-S177A/P60S) with increased infectivity or lower immunogenicity significantly (P < 0.001) prolonged the mOS from 11 days in the control cohort to 23 days in the SVV-S177A cohort and the SVV-S177A/P60S cohort in the NSCLC-bearing athymic mouse model, which may provide the direction for modifying SVV to improve the effect of oncolysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Picornaviridae , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Pulmão , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Camundongos Nus , Picornaviridae/genética
12.
Microb Pathog ; 187: 106535, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176463

RESUMO

Tuberculosis remains a threat to public health. The only approved vaccine, Bacillus Calmette-Guérin (BCG), is administered intradermally and provides limited protection, and its effect on innate immunity via the respiratory route has not been fully elucidated. A mouse model with genetically depleted TREM1 and seven-color flow cytometry staining were used to characterize the comprehensive immune response induced by respiratory BCG, through evaluating organ bacterial loads, lung histopathology, and lung immunohistochemistry. During respiratory BCG infection, the murine lungs displayed effective bacterial clearance. Notably, marked differences in neutrophils were observed between thymus and bone marrow cells, characterized by a significant increase in the expression of the triggering receptor expressed on myeloid cells 1 (TREM1). Subsequently, upon depletion of TREM1, a reduction in pulmonary neutrophils was observed, which further exacerbated bacterial loads and resulted in worsened pathology following respiratory BCG infection. In summary, up-regulated expression of TREM1 in rapidly increasing circulating neutrophil by pulmonary BCG is required for an efficient host response to BCG infection, and suggests the important role of TREM1 in neutrophil-related pulmonary bacteria clearance and pathology.


Assuntos
Bacillus , Mycobacterium bovis , Animais , Camundongos , Vacina BCG , Pulmão/patologia , Neutrófilos , Receptor Gatilho 1 Expresso em Células Mieloides
13.
Cell Commun Signal ; 22(1): 44, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233877

RESUMO

Bacterial meningitis remains a leading cause of infection-related mortality worldwide. Although Escherichia coli (E. coli) is the most common etiology of neonatal meningitis, the underlying mechanisms governing bacterial blood-brain barrier (BBB) disruption during infection remain elusive. We observed that infection of human brain microvascular endothelial cells with meningitic E. coli triggers the activation of early growth response 1 (Egr-1), a host transcriptional activator. Through integrated chromatin immunoprecipitation sequencing and transcriptome analysis, we identified Egr-1 as a crucial regulator for maintaining BBB integrity. Mechanistically, Egr-1 induced cytoskeletal changes and downregulated tight junction protein expression by directly targeting VEGFA, PDGFB, and ANGPTL4, resulting in increased BBB permeability. Meanwhile, Egr-1 also served as a master regulator in the initiation of neuroinflammatory response during meningitic E. coli infection. Our findings support an Egr-1-dependent mechanism of BBB disruption by meningitic E. coli, highlighting a promising therapeutic target for bacterial meningitis.


Assuntos
Meningites Bacterianas , Meningite devida a Escherichia coli , Humanos , Recém-Nascido , Barreira Hematoencefálica/microbiologia , Células Endoteliais/metabolismo , Escherichia coli , Meningites Bacterianas/metabolismo , Meningite devida a Escherichia coli/metabolismo
14.
Cell Commun Signal ; 22(1): 123, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360663

RESUMO

BACKGROUND: Meningitic Escherichia coli (E. coli) is the major etiological agent of bacterial meningitis, a life-threatening infectious disease with severe neurological sequelae and high mortality. The major cause of central nervous system (CNS) damage and sequelae is the bacterial-induced inflammatory storm, where the immune response of the blood-brain barrier (BBB) is crucial. METHODS: Western blot, real-time PCR, enzyme-linked immunosorbent assay, immunofluorescence, and dual-luciferase reporter assay were used to investigate the suppressor role of transforming growth factor beta 1 (TGFß1) in the immune response of brain microvascular endothelial cells elicited by meningitic E. coli. RESULT: In this work, we showed that exogenous TGFß1 and induced noncanonical Hedgehog (HH) signaling suppressed the endothelial immune response to meningitic E. coli infection via upregulation of intracellular miR-155. Consequently, the increased miR-155 suppressed ERK1/2 activation by negatively regulating KRAS, thereby decreasing IL-6, MIP-2, and E-selectin expression. In addition, the exogenous HH signaling agonist SAG demonstrated promising protection against meningitic E. coli-induced neuroinflammation. CONCLUSION: Our work revealed the effect of TGFß1 antagonism on E. coli-induced BBB immune response and suggested that activation of HH signaling may be a potential protective strategy for future bacterial meningitis therapy. Video Abstract.


Assuntos
Meningites Bacterianas , Meningite devida a Escherichia coli , MicroRNAs , Humanos , Escherichia coli/genética , Proteínas Hedgehog/metabolismo , Células Endoteliais/metabolismo , Meningite devida a Escherichia coli/metabolismo , Encéfalo/metabolismo , Barreira Hematoencefálica/microbiologia , Meningites Bacterianas/metabolismo , Imunidade , MicroRNAs/metabolismo
15.
Vet Res ; 55(1): 104, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39210406

RESUMO

Meningitis induced by Pasteurella multocida has been substantially described in clinical practice in both human and veterinary medicine, but the underlying mechanisms have not been previously reported. In this study, we investigated the influence of P. multocida infection on the permeability of the blood-brain barrier (BBB) using different models. Our in vivo tests in a mouse model and in vitro tests using human brain microvascular endothelial cell (hBMEC) model showed that P. multocida infection increased murine BBB permeability in mice and hBMEC monolayer permeability. Furthermore, we observed that P. multocida infection resulted in decreased expression of tight junctions (ZO1, claudin-5, occludin) and adherens junctions (E-cadherin) between neighboring hBMECs. Subsequent experiments revealed that P. multocida infection promoted the activation of hypoxia inducible factor-1α (HIF-1α)/vascular endothelial growth factor A (VEGFA) signaling and NF-κB signaling, and suppressed the HIF-1α/VEGFA significantly remitted the decrease in ZO1/E-cadherin induced by P. multocida infection (P < 0.001). NF-κB signaling was found to contribute to the production of chemokines such as TNF-1α, IL-ß, and IL-6. Additionally, transmission electron microscopy revealed that paracellular migration might be the strategy employed by P. multocida to cross the BBB. This study provides the first evidence of the migration strategy used by P. multocida to traverse the mammalian BBB. The data presented herein will contribute to a better understanding of the pathogenesis of the zoonotic pathogen P. multocida.


Assuntos
Junções Aderentes , Barreira Hematoencefálica , Células Endoteliais , Infecções por Pasteurella , Pasteurella multocida , Junções Íntimas , Animais , Pasteurella multocida/fisiologia , Barreira Hematoencefálica/microbiologia , Camundongos , Junções Aderentes/metabolismo , Infecções por Pasteurella/veterinária , Infecções por Pasteurella/microbiologia , Células Endoteliais/microbiologia , Células Endoteliais/fisiologia , Junções Íntimas/metabolismo , Humanos , Encéfalo/microbiologia , Encéfalo/irrigação sanguínea
16.
Proteins ; 91(8): 1130-1139, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37171131

RESUMO

Porcine circovirus type 2 (PCV2) can cause porcine circovirus-associated disease (PCVAD), which causes significant economic losses to the global pig industry annually. There are no effective antiviral drugs used to control and treat PCV2, and prevention is mainly obtained through vaccination. PCV2 genome replicates through the rolling circle replication (RCR) mechanism involving Rep and Rep', so analyzing the holistic structure of Rep and Rep' will help us better understand the replication process of PCV2. However, there are no reports on the integral structure of Rep' and Rep, which seriously hinders the research of the viral replication. By using the x-ray diffraction method, the structure of the Rep' dimer was resolved by us in this study. Structural analysis revealed that Rep' is a dimer formed by the interaction of the C-terminal domain. The two Rep' form a positively charged groove, which may play an essential role in the viral binding of dsDNA. Together, this study help to understand the replication process of the virus and may also provide new insights into the development of antiviral drugs.


Assuntos
Circovirus , Proteínas Virais , Animais , Suínos , Proteínas Virais/química , Circovirus/genética , Circovirus/metabolismo , Replicação Viral/genética
17.
BMC Genomics ; 24(1): 62, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737703

RESUMO

BACKGROUND: The snub-nosed monkey (Rhinopithecus roxellanae) is an endangered animal species mainly distributed in China and needs to be protected. Gut microbiome is an important determinant of animal health and population survival as it affects the adaptation of the animals to different foods and environments under kinetic changes of intrinsic and extrinsic factors. Therefore, this study aimed to elucidate gut fecal microbiome profiles of snub-nosed monkeys affected by several extrinsic and intrinsic factors, including raising patterns (captive vs. wild), age, sex, and diarrheal status to provide a reference for making protection strategies. RESULTS: The 16S rRNA gene sequencing was firstly used to pre-check clustering of 38 fecal samples from the monkeys including 30 wild and 8 captive (5 healthy and 3 diarrheal) from three Regions of Shennongjia Nature Reserve, Hubei Province, China. Then the 24 samples with high-quality DNA from 18 wild and 6 captive (4 healthy and 2 diarrheal) monkeys were subjected to shotgun metagenomic sequencing to characterize bacterial gut microbial communities. We discovered that the raising pattern (captive and wild) rather than age and sex was the predominant factor attributed to gut microbiome structure and proportionality. Wild monkeys had significantly higher bacterial diversity and lower Bacteroidetes/Firmicutes ratios than captive animals. Moreover, the gut microbiomes in wild healthy monkeys were enriched for the genes involved in fatty acid production, while in captive animals, genes were enriched for vitamin biosynthesis and metabolism and amino acid biosynthesis from carbohydrate intermediates. Additionally, a total of 37 antibiotic resistant genes (ARG) types were detected. Unlike the microbiome diversity, the captive monkeys have a higher diversity of ARG than the wild animals. CONCLUSION: Taken together, we highlight the importance of self-reprogramed metabolism in the snub-nosed monkey gut microbiome to help captive and wild monkeys adapt to different intrinsic and extrinsic environmental change.


Assuntos
Colobinae , Microbioma Gastrointestinal , Presbytini , Animais , Presbytini/genética , Microbioma Gastrointestinal/genética , Colobinae/genética , Colobinae/microbiologia , RNA Ribossômico 16S/genética , Espécies em Perigo de Extinção , Bactérias/genética , Diarreia
18.
J Gen Virol ; 104(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37097881

RESUMO

Swine are considered to be an important intermediate host in the cycle of Japanese encephalitis virus (JEV) infection. Most existing antiviral studies of JEV mainly focus on the host factor of the dead-end hosts. However, little research has addressed this in swine. Here, we found that swine interferon alpha-inducible protein 6 (sIFI6) possessed antiviral activity against JEV. In vitro studies showed that overexpression of sIFI6 inhibited the infection of JEV, while sIFI6 knockdown enhanced the infection of JEV in PK-15 cells. In addition, we also found that the structural integrity of sIFI6 was required by anti-JEV activity and that sIFI6 interacted with JEV nonstructural protein 4A (NS4A), an integral membrane protein with a pivotal function in replication complex during JEV replication. The interaction domain was mapped to the fourth transmembrane domain (TMD), also known as the 2K peptide of NS4A. The antiviral activity of sIFI6 was regulated by endoplasmic reticulum (ER) stress-related protein, Bip. In vivo studies revealed that sIFI6 alleviated symptoms of JEV infection in C57BL/6 mice. In addition, the antiviral spectrum of sIFI6 showed that sIFI6 specifically inhibited JEV infection. In conclusion, this study identified sIFI6 as a host factor against JEV infection for the first time. Our findings provide a potential drug target against JEV infection.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Animais , Camundongos , Antivirais/uso terapêutico , Linhagem Celular , Vírus da Encefalite Japonesa (Espécie)/metabolismo , Encefalite Japonesa/metabolismo , Camundongos Endogâmicos C57BL , Suínos , Replicação Viral , Fosfoproteínas/metabolismo , Proteínas Nucleares/metabolismo
19.
J Gen Virol ; 104(11)2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37991423

RESUMO

Pseudorabies virus (PRV) belongs to the alpha herpesvirus family and is responsible for Aujeszky's disease in pigs. Similar to other alpha herpesviruses, PRV establishes a lifelong latent infection in trigeminal ganglion. These latently infected pigs serve as a reservoir for recurrent infections when reactivation is triggered, making the eradication of PRV a challenging task. However, the molecular mechanism underlying PRV latency and reactivation in neurons is still poorly understood due to limitations in the in vitro model. To establish a pseudorabies virus latency and reactivation model in primary neuron cultures, we isolated dorsal root ganglion (DRG) from newborn Kunming mice using a method named epineurium-pulling for DRG collection (EPDC) and cultured primary neurons in vitro. A dual-colour recombinant PRV BAC mRuby-VP16 was constructed and 0.5 multiplicity of infection (MOI) was found as an appropriate dose in the presence of aciclovir to establish latency. Reactivation was induced using UV-inactivated herpesviruses or a series of chemical inhibitors. Interestingly, we found that not only UV-PRV, but also UV-HSV-1 and UV-BHoV-5 were able to induce rapid PRV reactivation. The efficiency of reactivation for LY294002, forskolin, etoposide, dexamethasone, and acetylcholine was found to be dependent on their concentration. In conclusion, we developed a valuable model of PRV latency and reactivation, which provides a basis for future mechanism research.


Assuntos
Herpesvirus Suídeo 1 , Pseudorraiva , Camundongos , Animais , Suínos , Herpesvirus Suídeo 1/fisiologia , Gânglios Espinais , Latência Viral , Ativação Viral
20.
J Neuroinflammation ; 20(1): 173, 2023 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-37481642

RESUMO

Neuroinflammation has been implicated in the initiation and progression of several central nervous system (CNS) disorders, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, ischemic stroke, traumatic brain injury, spinal cord injury, viral encephalitis, and bacterial encephalitis. Microglia and astrocytes are essential in neural development, maintenance of synaptic connections, and homeostasis in a healthy brain. The activation of astrocytes and microglia is a defense mechanism of the brain against damaged tissues and harmful pathogens. However, their activation triggers neuroinflammation, which can exacerbate or induce CNS injury. Non-coding RNAs (ncRNAs) are functional RNA molecules that lack coding capabilities but can actively regulate mRNA expression and function through various mechanisms. ncRNAs are highly expressed in astrocytes and microglia and are potential mediators of neuroinflammation. We reviewed the recent research progress on the role of miRNAs, lncRNAs, and circRNAs in regulating neuroinflammation in various CNS diseases. Understanding how these ncRNAs affect neuroinflammation will provide important therapeutic insights for preventing and managing CNS dysfunction.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , Astrócitos , Microglia , Doenças Neuroinflamatórias , RNA Longo não Codificante/genética
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