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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Article in English | MEDLINE | ID: mdl-32814014

ABSTRACT

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Subject(s)
Genetic Variation/genetics , Tick-Borne Diseases/microbiology , Ticks/genetics , Animals , Cell Line , Disease Vectors , Host Specificity/genetics
2.
Nature ; 583(7815): 282-285, 2020 07.
Article in English | MEDLINE | ID: mdl-32218527

ABSTRACT

The ongoing outbreak of viral pneumonia in China and across the world is associated with a new coronavirus, SARS-CoV-21. This outbreak has been tentatively associated with a seafood market in Wuhan, China, where the sale of wild animals may be the source of zoonotic infection2. Although bats are probable reservoir hosts for SARS-CoV-2, the identity of any intermediate host that may have facilitated transfer to humans is unknown. Here we report the identification of SARS-CoV-2-related coronaviruses in Malayan pangolins (Manis javanica) seized in anti-smuggling operations in southern China. Metagenomic sequencing identified pangolin-associated coronaviruses that belong to two sub-lineages of SARS-CoV-2-related coronaviruses, including one that exhibits strong similarity in the receptor-binding domain to SARS-CoV-2. The discovery of multiple lineages of pangolin coronavirus and their similarity to SARS-CoV-2 suggests that pangolins should be considered as possible hosts in the emergence of new coronaviruses and should be removed from wet markets to prevent zoonotic transmission.


Subject(s)
Betacoronavirus/genetics , Betacoronavirus/isolation & purification , Eutheria/virology , Evolution, Molecular , Genome, Viral/genetics , Sequence Homology, Nucleic Acid , Amino Acid Sequence , Animals , Betacoronavirus/chemistry , Betacoronavirus/classification , COVID-19 , China/epidemiology , Chiroptera/virology , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Coronavirus Infections/virology , Disease Reservoirs/virology , Genomics , Humans , Malaysia , Pandemics , Phylogeny , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , Recombination, Genetic , SARS-CoV-2 , Sequence Alignment , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Zoonoses/virology
3.
PLoS Pathog ; 19(8): e1011580, 2023 08.
Article in English | MEDLINE | ID: mdl-37566637

ABSTRACT

The multigene family genes (MGFs) in the left variable region (LVR) of the African swine fever virus (ASFV) genome have been reported to be involved in viral replication in primary porcine alveolar macrophages (PAMs) and virulence in pigs. However, the exact functions of key MGFs in the LVR that regulate the replication and virulence of ASFV remain unclear. In this study, we identified the MGF300-2R gene to be critical for viral replication in PAMs by deleting different sets of MGFs in the LVR from the highly virulent strain ASFV HLJ/18 (ASFV-WT). The ASFV mutant lacking the MGF300-2R gene (Del2R) showed a 1-log reduction in viral titer, and induced higher IL-1ß and TNF-α production in PAMs than did ASFV-WT. Mechanistically, the MGF300-2R protein was found to interact with and degrade IKKα and IKKß via the selective autophagy pathway. Furthermore, we showed that MGF300-2R promoted the K27-linked polyubiquitination of IKKα and IKKß, which subsequently served as a recognition signal for the cargo receptor TOLLIP-mediated selective autophagic degradation. Importantly, Del2R exhibited a significant reduction in both replication and virulence compared with ASFV-WT in pigs, likely due to the increased IL-1ß and TNF-α, indicating that MGF300-2R is a virulence determinant. These findings reveal that MGF300-2R suppresses host innate immune responses by mediating the degradation of IKKα and IKKß, which provides clues to paving the way for the rational design of live attenuated vaccines to control ASF.


Subject(s)
African Swine Fever Virus , African Swine Fever , Swine , Animals , African Swine Fever Virus/genetics , Virulence , I-kappa B Kinase/genetics , I-kappa B Kinase/metabolism , Tumor Necrosis Factor-alpha/metabolism , Macrophages , Protein Serine-Threonine Kinases/metabolism , Autophagy
4.
J Biol Chem ; 299(11): 105347, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37838171

ABSTRACT

The pseudorabies virus (PRV) TJ strain, a variant of PRV, induces more severe neurological symptoms and higher mortality in piglets and mice than the PRV SC strain isolated in 1980. However, the mechanism underlying responsible for the discrepancy in virulence between these strains remains unclear. Our study investigated the differences in neurotropism between PRV TJ and PRV SC using both in vitro and in vivo models. We discovered that PRV TJ enters neural cells more efficiently than PRV SC. Furthermore, we found that PRV TJ has indistinguishable genomic DNA replication capability and axonal retrograde transport dynamics compared to the PRV SC. To gain deeper insights into the mechanisms underlying these differences, we constructed gene-interchanged chimeric virus constructs and assessed the affinity between envelope glycoprotein B, C, and D (gD) and corresponding receptors. Our findings confirmed that mutations in these envelope proteins, particularly gD, significantly contributed to the heightened attachment and penetration capabilities of PRV TJ. Our study revealed the critical importance of the gDΔR278/P279 and gDV338A in facilitating viral invasion. Furthermore, our observations indicated that mutations in envelope proteins have a more significant impact on viral invasion than on virulence in the mouse model. Our findings provide valuable insights into the roles of natural mutations on the PRV envelope glycoproteins in cell tropism, which sheds light on the relationship between cell tropism and clinical symptoms and offers clues about viral evolution.


Subject(s)
Herpesvirus 1, Suid , Pseudorabies , Viral Envelope Proteins , Viral Tropism , Animals , Mice , Genomics , Herpesvirus 1, Suid/genetics , Mutagenesis , Mutation , Pseudorabies/genetics , Swine , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism
5.
J Virol ; 97(9): e0056923, 2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37607059

ABSTRACT

Proinflammatory factors play important roles in the pathogenesis of African swine fever virus (ASFV), which is the causative agent of African swine fever (ASF), a highly contagious and severe hemorrhagic disease. Efforts in the prevention and treatment of ASF have been severely hindered by knowledge gaps in viral proteins responsible for modulating host antiviral responses. In this study, we identified the I10L protein (pI10L) of ASFV as a potential inhibitor of the TNF-α- and IL-1ß-triggered NF-κB signaling pathway, the most canonical and important part of host inflammatory responses. The ectopically expressed pI10L remarkably suppressed the activation of NF-κB signaling in HEK293T and PK-15 cells. The ASFV mutant lacking the I10L gene (ASFVΔI10L) induced higher levels of proinflammatory cytokines production in primary porcine alveolar macrophages (PAMs) compared with its parental ASFV HLJ/2018 strain (ASFVWT). Mechanistic studies suggest that pI10L inhibits IKKß phosphorylation by reducing the K63-linked ubiquitination of NEMO, which is necessary for the activation of IKKß. Morever, pI10L interacts with the kinase domain of IKKß through its N-terminus, and consequently blocks the association of IKKß with its substrates IκBα and p65, leading to reduced phosphorylation. In addition, the nuclear translocation efficiency of p65 was also altered by pI10L. Further biochemical evidence supported that the amino acids 1-102 on pI10L were essential for the pI10L-mediated suppression of the NF-κB signaling pathway. The present study clarifies the immunosuppressive activity of pI10L, and provides novel insights into the understanding of ASFV pathobiology and the development of vaccines against ASF. IMPORTANCE African swine fever (ASF), caused by the African swine fever virus (ASFV), is now widespread in many countries and severely affects the commercial rearing of swine. To date, few safe and effective vaccines or antiviral strategies have been marketed due to large gaps in knowledge regarding ASFV pathobiology and immune evasion mechanisms. In this study, we deciphered the important role of the ASFV-encoded I10L protein in the TNF-α-/IL-1ß-triggered NF-κB signaling pathway. This study provides novel insights into the pathogenesis of ASFV and thus contributes to the development of vaccines against ASF.

6.
J Virol ; 97(10): e0082423, 2023 10 31.
Article in English | MEDLINE | ID: mdl-37724880

ABSTRACT

IMPORTANCE: African swine fever (ASF) is an acute, hemorrhagic, and severe porcine infectious disease caused by African swine fever virus (ASFV). ASF outbreaks severely threaten the global pig industries and result in serious economic losses. No safe and efficacious commercial vaccine is currently available except in Vietnam. To date, large gaps in the knowledge concerning viral biological characteristics and immunoevasion strategies have hindered the ASF vaccine design. In this study, we demonstrate that pD129L negatively regulates the type I interferon (IFN) signaling pathway by interfering with the interaction of the transcriptional coactivator p300 and IRF3, thereby inhibiting the induction of type I IFNs. This study reveals a novel immunoevasion strategy employed by ASFV, shedding new light on the intricate mechanisms for ASFV to evade the host immune responses.


Subject(s)
African Swine Fever Virus , African Swine Fever , E1A-Associated p300 Protein , Interferon Regulatory Factor-3 , Interferon Type I , Animals , African Swine Fever/virology , Interferon Type I/metabolism , Interferon-beta/metabolism , Swine , Transcription Factors/metabolism , Vaccines/metabolism , E1A-Associated p300 Protein/metabolism , Interferon Regulatory Factor-3/metabolism , Immune Evasion
7.
J Virol ; 96(22): e0095422, 2022 11 23.
Article in English | MEDLINE | ID: mdl-36326277

ABSTRACT

The H240R protein (pH240R), encoded by the H240R gene of African swine fever virus (ASFV), is a 241-amino-acid capsid protein. We previously showed that the deletion of H240R from the ASFV genome, creating ASFV-ΔH240R, resulted in an approximately 2-log decrease in infectious virus production compared with the wild-type ASFV strain (ASFV-WT), and ASFV-ΔH240R induced higher interleukin 1ß (IL-1ß) production in porcine alveolar macrophages (PAMs) than did ASFV-WT, but the underlying mechanism remains to be elucidated. Here, we demonstrate that the activation of the NF-κB signaling and NLRP3 inflammasome was markedly induced in PAMs upon ASFV-ΔH240R infection compared with ASFV-WT. Moreover, pH240R inhibited NF-κB activation by interacting with NEMO and promoting the autophagy-mediated lysosomal degradation of NEMO, resulting in reduced pro-IL-1ß transcription. Strikingly, NLRP3 deficiency in PAMs inhibited the ASFV-ΔH240R-induced IL-1ß secretion and caspase 1 activation, indicating an essential role of NLRP3 inflammasome activation during ASFV-ΔH240R replication. Mechanistically, pH240R interacted with NLRP3 to inhibit its oligomerization, leading to decreased IL-1ß production. Furthermore, the inhibition of the NF-κB signaling and NLRP3 inflammasome activation promoted ASFV-ΔH240R replication in PAMs. Taken together, the results of this study reveal an antagonistic mechanism by which pH240R suppresses the host immune response by manipulating activation of the NF-κB signaling and NLRP3 inflammasome, which might guide the rational design of live attenuated vaccines or therapeutic strategies against ASF in the future. IMPORTANCE African swine fever (ASF), a lethal hemorrhagic disease, is caused by African swine fever virus (ASFV). There are no commercially available vaccines or antivirals for the disease. Here, we showed that ASFV with a deletion of the H240R gene exhibits high-level expression of interleukin 1ß (IL-1ß), a proinflammatory cytokine, in porcine alveolar macrophages and that the H240R protein (pH240R) exhibits robust inhibitory effects on IL-1ß transcription and production. More specifically, pH240R inhibited NF-κB activation via the autophagy-mediated lysosomal degradation of NEMO, leading to the decrease of pro-IL-1ß transcription. In addition, pH240R interacted with NLRP3 to inhibit its oligomerization, leading to decreased IL-1ß production. Our results indicate that pH240R is involved in the evasion of host innate immunity and provide a novel target for the development of a live attenuated vaccine against ASF.


Subject(s)
African Swine Fever Virus , African Swine Fever , Animals , Swine , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , African Swine Fever Virus/genetics , African Swine Fever Virus/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , NF-kappa B/metabolism
8.
J Virol ; 96(3): e0166721, 2022 02 09.
Article in English | MEDLINE | ID: mdl-34787458

ABSTRACT

African swine fever virus (ASFV) is a complex nucleocytoplasmic large DNA virus that causes African swine fever, a lethal hemorrhagic disease that currently threatens the pig industry. Recent studies have identified the viral structural proteins of infectious ASFV particles. However, the functional roles of several ASFV structural proteins remain largely unknown. Here, we characterized the function of the ASFV structural protein H240R (pH240R) in virus morphogenesis. pH240R was identified as a capsid protein by using immunoelectron microscopy and interacted with the major capsid protein p72 by pulldown assays. Using a recombinant ASFV, ASFV-ΔH240R, with the H240R gene deleted from the wild-type ASFV (ASFV-WT) genome, we revealed that the infectious progeny virus titers were reduced by approximately 2.0 logs compared with those of ASFV-WT. Furthermore, we demonstrated that the growth defect was due to the generation of noninfectious particles with a higher particle-to-infectious titer ratio in ASFV-ΔH240R-infected primary porcine alveolar macrophages (PAMs) than in those infected with ASFV-WT. Importantly, we found that pH240R did not affect virus-cell binding, endocytosis, or egress but did affect ASFV assembly; noninfectious virions containing large aberrant tubular and bilobulate structures comprised nearly 98% of all virions observed in ASFV-ΔH240R-infected PAMs by electron microscopy. Notably, we demonstrated that ASFV-ΔH240R infection induced high-level expression of inflammatory cytokines in PAMs. Collectively, we show for the first time that pH240R is essential for ASFV icosahedral capsid formation and infectious particle production. Also, these results highlight the importance of pH240R in ASFV morphogenesis and provide a novel target for the development of ASF vaccines and antivirals. IMPORTANCE African swine fever is a lethal hemorrhagic disease of global concern that is caused by African swine fever virus (ASFV). Despite extensive research, there exist relevant gaps in knowledge of the fundamental biology of the viral life cycle. In this study, we identified pH240R as a capsid protein that interacts with the major capsid protein p72. Furthermore, we showed that pH240R was required for the efficient production of infectious progeny virions as indicated by the H240R-deleted ASFV mutant (ASFV-ΔH240R). More specifically, pH240R directs the morphogenesis of ASFV toward the icosahedral capsid in the process of assembly. In addition, ASFV-ΔH240R infection induced high-level expression of inflammatory cytokines in primary porcine alveolar macrophages. Our results elucidate the role of pH240R in the process of ASFV assembly, which may instruct future research on effective vaccines or antiviral strategies.


Subject(s)
African Swine Fever Virus/physiology , African Swine Fever/genetics , African Swine Fever/metabolism , Capsid Proteins/genetics , Cytokines/metabolism , Macrophages/metabolism , Sequence Deletion , African Swine Fever/pathology , African Swine Fever Virus/ultrastructure , Amino Acid Sequence , Animals , Capsid Proteins/chemistry , Capsid Proteins/metabolism , Cytokines/genetics , Disease Susceptibility/immunology , Gene Expression Profiling , Gene Expression Regulation, Viral , Genome, Viral , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/immunology , Macrophages/immunology , Swine , Virion/ultrastructure , Virus Internalization , Virus Replication
9.
J Virol ; 96(9): e0195721, 2022 05 11.
Article in English | MEDLINE | ID: mdl-35412346

ABSTRACT

African swine fever is a lethal hemorrhagic disease of pigs caused by African swine fever virus (ASFV), which greatly threatens the pig industry in many countries. Deletion of virulence-associated genes to develop live attenuated ASF vaccines is considered to be a promising strategy. A recent study has revealed that the A137R gene deletion results in ASFV attenuation, but the underlying mechanism remains unknown. To elucidate the mechanism of the A137R gene regulating ASFV virulence, an ASFV mutant with the A137R gene deleted (ASFV-ΔA137R) was generated based on the wild-type ASFV HLJ/2018 strain (ASFV-WT). Using transcriptome sequencing analysis, we found that ASFV-ΔA137R induced higher type I interferon (IFN) production in primary porcine alveolar macrophages (PAMs) than did ASFV-WT. Overexpression of the A137R protein (pA137R) inhibited the activation of IFN-ß or IFN-stimulated response element. Mechanistically, pA137R interacts with TANK-binding kinase 1 (TBK1) and promotes the autophagy-mediated lysosomal degradation of TBK1, which blocks the nuclear translocation of interferon regulator factor 3, leading to decreased type I IFN production. Taken together, our findings clarify that pA137R negatively regulates the cGAS-STING-mediated IFN-ß signaling pathway via the autophagy-mediated lysosomal degradation of TBK1, which highlights the involvement of pA137R regulating ASFV virulence. IMPORTANCE African swine fever (ASF) is a lethal viral disease of pigs caused by African swine fever virus (ASFV). No commercial vaccines and antiviral treatments are available for the prevention and control of the disease. Several virulence-associated genes of ASFV have been identified, but the underlying attenuation mechanisms are not clear. Compared with the virulent parental ASFV, the A137R gene-deleted ASFV mutant promoted the expression of type I interferon (IFN) in primary porcine alveolar macrophages. Further analysis indicated that the A137R protein negatively regulated the cGAS-STING-mediated IFN-ß signaling pathway through targeting TANK-binding kinase 1 (TBK1) for autophagy-mediated lysosomal degradation. This study not only facilitates the understanding of ASFV immunoevasion strategies, but also provides new clues to the development of live attenuated ASF vaccines.


Subject(s)
African Swine Fever Virus , Autophagy , Interferon-beta , Protein Serine-Threonine Kinases , Viral Proteins , African Swine Fever , African Swine Fever Virus/genetics , Animals , Interferon-beta/metabolism , Lysosomes/metabolism , Macrophages, Alveolar/virology , Membrane Proteins , Nucleotidyltransferases/metabolism , Protein Serine-Threonine Kinases/metabolism , Swine , Viral Proteins/genetics , Virulence
10.
Appl Environ Microbiol ; 88(11): e0045222, 2022 06 14.
Article in English | MEDLINE | ID: mdl-35588273

ABSTRACT

African swine fever (ASF) is a highly contagious disease of domestic pigs and wild boar with high morbidity and mortality caused by African swine fever virus (ASFV). Due to the lack of commercial vaccines and treatments for ASF, cleaning and disinfection remain one of the most effective biosecurity measures to control ASF. Our previous studies have shown that ASFV can be inactivated by 0.25 to 5% highly complexed iodine (HPCI) in 5 to 30 min. This study evaluated the synergistic inactivation effects of HPCI combined with compound organic acids (COAs) against ASFV. The results showed that the inactivation rates of HPCI, COAs, and HPCI+COAs on the reporter ASFV expressing the green fluorescent protein increased in dose- and time-dependent manners. The best inactivation effects were obtained when the compatibility ratio of HPCI and COAs was 5:1, and the ideal temperature was 25°C. Furthermore, there were no significant differences when comparing the efficacy of HPCI combined with COAs (HPCI+COAs) in inactivating wild-type ASFV and the reporter ASFV (P > 0.05). ASFV of 104.0 50% tissue culture infective dose (TCID50)/mL was completely inactivated by 0.13% HPCI (0.0065% effective iodine), 0.06% COAs, or 0.13% HPCI+COAs (approximately 0.0054% effective iodine), respectively, while 106.0 TCID50/mL ASFV was completely inactivated by 1.00% HPCI (0.05% effective iodine), 0.50% COAs, or 1.00% HPCI+COAs (0.042% effective iodine), respectively. It was found that the combination index (CI) of HPCI and COAs was less than 1 under different conditions. This study demonstrated that HPCI+COAs could synergistically inactivate ASFV and represent an effective compound disinfectant for the control of ASF. IMPORTANCE African swine fever (ASF) is a highly contagious disease of swine with high morbidity and mortality caused by African swine fever virus (ASFV). Due to the lack of commercial vaccines and treatment available for ASF, effective disinfectants and the proper use of them are essential to inactivate ASFV. The significance of this research is in searching for an ideal disinfectant that has the advantages of low toxicity and nonpollution and can inactivate ASFV efficiently. In this study, we demonstrated that HPCI+COAs had synergistic effects on inactivating ASFV. Thus, HPCI+COAs could be used as an effective disinfectant for the control of ASF.


Subject(s)
African Swine Fever Virus , African Swine Fever , Disinfectants , Iodine , African Swine Fever/prevention & control , Animals , Disinfectants/pharmacology , Iodine/pharmacology , Sus scrofa , Swine
11.
BMC Cancer ; 22(1): 809, 2022 Jul 22.
Article in English | MEDLINE | ID: mdl-35869490

ABSTRACT

BACKGROUND: Lung cancer is the leading cause of malignancy-related mortality and lung adenocarcinoma accounts for about 40% of lung malignancies. The aim of this study was to investigate the associations of intraflagellar transport protein 20 (IFT20) and Golgi matrix protein 130 (GM130) expression with clinicopathological features and survival in patients with lung adenocarcinoma. METHODS: The expressions of IFT20 and GM130 protein in cancerous and matched adjacent lung tissues of 235 patients with lung adenocarcinoma were assessed by tissue microarray and immunohistochemistry, which were indicated by the mean optical density (IOD/area), the rate of positive staining cells and staining intensity score. The correlation between IFT20 and GM130 protein was assessed by Spearman's rank correlation. Associations of IFT20 and GM130 protein expression with clinicopathological features of patients were analyzed by multivariate logistic regression models. The survival analysis of patients was performed by Cox proportional hazard regression models. RESULTS: With adjustment for multiple potential confounders, each one-point increase in IFT20 protein staining intensity score was significantly associated with 32% and 29% reduced risk for TNM stage in II ~ IV and lymphatic metastasis of patients, respectively (P < 0.05). And each one-point increase in GM130 protein staining intensity score was associated with a significant reduction in the risk of poor differentiation and tumors size > 7 cm by 29% and 38% for lung adenocarcinoma patients, respectively (P < 0.05). In stratified Cox model analysis, enhanced IFT20 staining intensity score was significantly decreased the risk of death by 16% for patients without distant metastasis. And elevated the IOD/area of GM130 expression significantly decreased the death risk of lung adenocarcinoma patients with tumor size > 7 cm or distant metastasis by 54% and 65%, respectively (P < 0.05). CONCLUSION: IFT20 and GM130 protein expressions were negatively associated with tumor differentiated types, size, TNM stage and lymphatic metastasis of lung adenocarcinoma. Both IFT20 and GM130 proteins have some protective effects on the survival of lung adenocarcinoma patients with specific clinicopathological features.


Subject(s)
Adenocarcinoma of Lung , Adenocarcinoma , Autoantigens/metabolism , Lung Neoplasms , Membrane Proteins/metabolism , Adenocarcinoma/pathology , Adenocarcinoma of Lung/pathology , Biomarkers, Tumor/metabolism , Carrier Proteins , Humans , Lung Neoplasms/pathology , Lymphatic Metastasis , Neoplasm Staging , Prognosis
12.
J Virol ; 94(17)2020 08 17.
Article in English | MEDLINE | ID: mdl-32581110

ABSTRACT

The classical swine fever virus (CSFV) live attenuated vaccine C-strain is adaptive to rabbits and attenuated in pigs, in contrast with the highly virulent CSFV Shimen strain. Previously, we demonstrated that P108 and T109 on the E2 glycoprotein (E2P108-T109) in domain I (E2DomainI) rather than R132, S133, and D191 in domain II (E2DomainII) determine C-strain's adaptation to rabbits (ATR) (Y. Li, L. Xie, L. Zhang, X. Wang, C. Li, et al., Virology 519:197-206, 2018). However, it remains elusive whether these critical amino acids affect the ATR of the Shimen strain and virulence in pigs. In this study, three chimeric viruses harboring E2P108-T109, E2DomainI, or E2DomainII of C-strain based on the non-rabbit-adaptive Shimen mutant vSM-HCLVErns carrying the Erns glycoprotein of C-strain were generated and evaluated. We found that E2P108-T109 or E2DomainI but not E2DomainII of C-strain renders vSM-HCLVErns adaptive to rabbits, suggesting that E2P108-T109 in combination with the Erns glycoprotein (E2P108-T109-Erns) confers ATR on the Shimen strain, creating new rabbit-adaptive CSFVs. Mechanistically, E2P108-T109-Erns of C-strain mediates viral entry during infection in rabbit spleen lymphocytes, which are target cells of C-strain. Notably, pig experiments showed that E2P108-T109-Erns of C-strain does not affect virulence compared with the Shimen strain. Conversely, the substitution of E2DomainII and Erns of C-strain attenuates the Shimen strain in pigs, indicating that the molecular basis of the CSFV ATR and that of virulence in pigs do not overlap. Our findings provide new insights into the mechanism of adaptation of CSFV to rabbits and the molecular basis of CSFV adaptation and attenuation.IMPORTANCE Historically, live attenuated vaccines produced by blind passage usually undergo adaptation in cell cultures or nonsusceptible hosts and attenuation in natural hosts, with a classical example being the classical swine fever virus (CSFV) lapinized vaccine C-strain, which was developed by hundreds of passages in rabbits. However, the mechanism of viral adaptation to nonsusceptible hosts and the molecular basis for viral adaptation and attenuation remain largely unknown. In this study, we demonstrated that P108 and T109 on the E2 glycoprotein together with the Erns glycoprotein of the rabbit-adaptive C-strain confer adaptation to rabbits on the highly virulent CSFV Shimen strain by affecting viral entry during infection but do not attenuate the Shimen strain in pigs. Our results provide vital information on the different molecular bases of CSFV adaptation to rabbits and attenuation in pigs.


Subject(s)
Adaptation, Physiological/physiology , Classical Swine Fever Virus/physiology , Classical Swine Fever/immunology , Glycoproteins/chemistry , Viral Envelope Proteins/chemistry , Animals , Cell Line , Chimera , Classical Swine Fever/prevention & control , Classical Swine Fever/virology , Disease Models, Animal , Genome, Viral , Glycoproteins/genetics , Rabbits , Receptor, EphB2 , Spleen/virology , Swine , Vaccines, Attenuated , Viral Envelope Proteins/genetics , Viral Vaccines/immunology , Viremia , Virulence , Virus Internalization , Virus Replication
13.
Article in English | MEDLINE | ID: mdl-34255621

ABSTRACT

Four obligatory anaerobic, Gram-stain-positive, non-motile and rod-shaped organisms (HF-1365T, HF-1362, HF-1101T and HF-4214) were isolated from faecal samples of healthy Chinese subjects. Results of 16S rRNA gene sequence analyses showed that these isolates belong to the genera Enorma (strains HF-1365T and HF-1362) and Eggerthella (strains HF-1101T and HF-4214), closest to Enorma massiliensis (both 98.6 %) and Eggerthella sinensis (98.0 and 97.8 %), respectively. The whole genome sequences of strains HF-1365T and HF-1101T were 2.3 and 4.2 Mb in size with 61.7 and 66.2 mol% DNA G+C content, respectively. The average nucleotide identity and digital DNA-DNA hybridization values indicated that strains HF-1365T and HF-1101T represent novel species in the genera Enorma and Eggerthella. Major fatty acid constituents (>10 %) of strains HF-1365T and HF-1362 were C12 : 0 (24.7 and 23.9 %), C14 : 0 (21.9 and 20.6 %) and summed feature 1 (C15 : 1iso H/C13 : 0 3OH; 12.8 and 10.8 %); those of strains HF-1101T and HF-4214 were C18 : 1 ω9c (32.4 and 33.1 %) and C16 : 0 (13.9 and 14.0 %). Strain HF-1365T had phospholipid, glycolipid, lipid and phosphoglycolipid without any known quinones, while strain HF-1101T had diphosphatidylglycerol as the major polar lipid and MK-7 (80.7 %) as the predominant quinone. On the basis of their phylogenetic and phenotypic characteristics, strains HF-1365T and HF-1101T represent two distinct species, respectively, in the genera Enorma and Eggerthella, for which the names Enorma shizhengliae sp. nov. (type strain HF-1365T=CGMCC 1.17435T=GDMCC 1.1705T=JCM 33601T) and Eggerthella guodeyinii sp. nov. (type strain HF-1101T=CGMCC 1.17436T=GDMCC 1.1668T=JCM 33773T) are proposed.


Subject(s)
Actinobacteria/classification , Feces/microbiology , Phylogeny , Actinobacteria/isolation & purification , Bacterial Typing Techniques , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Humans , Nucleic Acid Hybridization , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
14.
Infect Immun ; 88(4)2020 03 23.
Article in English | MEDLINE | ID: mdl-31907196

ABSTRACT

Spotted fever group rickettsia (SFGR) can cause mild to fatal illness. The early interaction between the host and rickettsia in skin is largely unknown, and the pathogenesis of severe rickettsiosis remains an important topic. A surveillance of SFGR infection by PCR of blood and skin biopsy specimens followed by sequencing and immunohistochemical (IHC) detection was performed on patients with a recent tick bite between 2013 and 2016. Humoral and cutaneous immunoprofiles were evaluated in different SFGR cases by serum cytokine and chemokine detection, skin IHC staining, and transcriptome sequencing (RNA-seq). A total of 111 SFGR cases were identified, including 79 "Candidatus Rickettsia tarasevichiae," 22 Rickettsia raoultii, 8 Rickettsia sibirica, and 2 Rickettsia heilongjiangensis cases. The sensitivity to detect SFGR in skin biopsy specimens (9/24, 37.5%) was significantly higher than that in blood samples (105/2,671, 3.9%) (P < 0.05). As early as 1 day after the tick bite, rickettsiae could be detected in the skin. R. sibirica infection was more severe than "Ca Rickettsia" and R. raoultii infections. Increased levels of serum interleukin-18 (IL-18), IP10, and monokine induced by gamma interferon (MIG) and decreased levels of IL-2 were observed in febrile patients infected with R. sibirica compared to those infected with "Ca Rickettsia." RNA-seq and IHC staining could not discriminate between SFGR-infected and uninfected tick bite skin lesions. However, the type I interferon (IFN) response was differently expressed between R. sibirica and R. raoultii infections at the cutaneous interface. It is concluded that skin biopsy specimens were more reliable for the detection of SFGR infection in human patients although the immunoprofile may be complicated by immunomodulators induced by the tick bite.


Subject(s)
Immunologic Factors/analysis , Rickettsia/growth & development , Skin/pathology , Spotted Fever Group Rickettsiosis/pathology , Tick Bites/complications , Biopsy , Cytokines/blood , Gene Expression Profiling , Humans , Immunohistochemistry , Skin/immunology , Skin/microbiology , Spotted Fever Group Rickettsiosis/immunology , Spotted Fever Group Rickettsiosis/microbiology
15.
J Virol ; 93(21)2019 11 01.
Article in English | MEDLINE | ID: mdl-31413123

ABSTRACT

In the host, many RING domain E3 ligases have been reported to inhibit viral replication through various mechanisms. In a previous screen, we found that porcine RING finger protein 114 (pRNF114), a RING domain E3 ubiquitin ligase, inhibits classical swine fever virus (CSFV) replication. This study aimed to clarify the underlying antiviral mechanism of pRNF114 against CSFV. Upon CSFV infection, pRNF114 mRNA was upregulated both in vitro and in vivo CSFV replication was significantly suppressed in PK-pRNF114 cells stably expressing pRNF114 by the lentivirus-delivered system, whereas CSFV growth was enhanced in PK-15 cells with RNF114 knockout by the CRISPR/Cas9 system. The RING domain of pRNF114, which has E3 ubiquitin ligase activity, is crucial for its antiviral activity. Mechanistically, pRNF114 interacted with the CSFV NS4B protein through their C-terminal domains, which led to the K27-linked polyubiquitination and degradation of NS4B through a proteasome-dependent pathway. Collectively, these findings indicate that pRNF114 as a critical regulator of CSFV replication and uncover a mechanism by which pRNF114 employs its E3 ubiquitin ligase activity to inhibit CSFV replication.IMPORTANCE Porcine RING finger protein 114 (pRNF114) is a member of the RING domain E3 ligases. In this study, it was shown that pRNF114 is a potential anti-CSFV factor and the anti-CSFV effect of pRNF114 depends on its E3 ligase activity. Notably, pRNF114 targets and catalyzes the K27-linked polyubiquitination of the NS4B protein and then promotes proteasome-dependent degradation of NS4B, inhibiting the replication of CSFV. To our knowledge, pRNF114 is the first E3 ligase to be identified as being involved in anti-CSFV activity, and targeting NS4B could be a crucial route for antiviral development.


Subject(s)
Classical Swine Fever Virus/physiology , Classical Swine Fever/prevention & control , Lysine/metabolism , Ubiquitin-Protein Ligases/metabolism , Ubiquitination , Viral Nonstructural Proteins/metabolism , Virus Replication , Animals , Classical Swine Fever/metabolism , Classical Swine Fever/virology , HEK293 Cells , Humans , Lysine/genetics , Swine , Ubiquitin-Protein Ligases/genetics , Viral Nonstructural Proteins/genetics
16.
J Virol ; 93(16)2019 08 15.
Article in English | MEDLINE | ID: mdl-31167908

ABSTRACT

Hemoglobin is an important oxygen-carrying protein and plays crucial roles in establishing host resistance against pathogens and in regulating innate immune responses. The hemoglobin subunit beta (HB) is an essential component of hemoglobin, and we have previously demonstrated that the antiviral role of the porcine HB (pHB) is mediated by promoting type I interferon pathways. Thus, considering the high homology between human HB (hHB) and pHB, we hypothesized that hHB also plays an important role in the antiviral innate immunity. In this study, we characterized hHB as a regulatory factor for the replication of RNA viruses by differentially regulating the RIG-I- and MDA5-mediated antiviral signaling pathways. Furthermore, we showed that hHB directly inhibited MDA5-mediated signaling by reducing the MDA5-double-stranded RNA (dsRNA) interaction. Additionally, hHB required hHB-induced reactive oxygen species (ROS) to promote RIG-I-mediated signaling through enhancement of K63-linked RIG-I ubiquitination. Taken together, our findings suggest that hHB is a pleiotropic regulator of RIG-I/MDA5-mediated antiviral responses and further highlight the importance of the intercellular microenvironment, including the redox state, in regulating antiviral innate immune responses.IMPORTANCE Hemoglobin, the most important oxygen-carrying protein, is involved in the regulation of innate immune responses. We have previously reported that the porcine hemoglobin subunit beta (HB) exerts antiviral activity through regulation of type I interferon production. However, the antiviral activities and the underlying mechanisms of HBs originating from other animals have been poorly understood. Here, we identified human HB (hHB) as a pleiotropic regulator of the replication of RNA viruses through regulation of RIG-I/MDA5-mediated signaling pathways. hHB enhances RIG-I-mediated antiviral responses by promoting RIG-I ubiquitination depending on the hHB-induced reactive oxygen species (ROS), while it blocks MDA5-mediated antiviral signaling by suppressing the MDA5-dsRNA interaction. Our results contribute to an understanding of the crucial roles of hHB in the regulation of the RIG-I/MDA5-mediated signaling pathways. We also provide novel insight into the correlation of the intercellular redox state with the regulation of antiviral innate immunity.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , DEAD Box Protein 58/metabolism , Disease Susceptibility , Immunity, Innate , Virus Diseases/etiology , Virus Diseases/metabolism , beta-Globins/metabolism , Cell Line , Disease Resistance , Host-Pathogen Interactions/immunology , Humans , Models, Biological , Prohibitins , RNA Viruses , Reactive Oxygen Species/metabolism , Receptors, Immunologic , Signal Transduction , Ubiquitination , Virus Replication , beta-Globins/genetics
17.
Sensors (Basel) ; 20(6)2020 Mar 19.
Article in English | MEDLINE | ID: mdl-32204375

ABSTRACT

Sensor selection plays an essential and fundamental role in prognostics and health management technology, and it is closely related to fault diagnosis, life prediction, and health assessment. The existing methods of sensor selection do not have an evaluation standard, which leads to different selection results. It is not helpful for the selection and layout of sensors. This paper proposes a comprehensive evaluation method of sensor selection for prognostics and health management (PHM) based on grey clustering. The described approach divides sensors into three grey classes, and defines and quantifies three grey indexes based on a dependency matrix. After a brief introduction to the whitening weight function, we propose a combination weight considering the objective data and subjective tendency to improve the effectiveness of the selection result. Finally, the clustering result of sensors is obtained by analyzing the clustering coefficient, which is calculated based on the grey clustering theory. The proposed approach is illustrated by an electronic control system, in which the effectiveness of different methods of sensor selection is compared. The result shows that the technique can give a convincing analysis result by evaluating the selection results of different methods, and is also very helpful for adjusting sensors to provide a more precise result. This approach can be utilized in sensor selection and evaluation for prognostics and health management.


Subject(s)
Biosensing Techniques , Electronics , Population Health Management , Prognosis , Algorithms , Cluster Analysis , Humans
18.
BMC Genomics ; 20(1): 983, 2019 Dec 16.
Article in English | MEDLINE | ID: mdl-31842750

ABSTRACT

BACKGROUND: Phenomics provides new technologies and platforms as a systematic phenome-genome approach. However, few studies have reported on the systematic mining of shared genetics among clinical biochemical indices based on phenomics methods, especially in China. This study aimed to apply phenomics to systematically explore shared genetics among 29 biochemical indices based on the Fangchenggang Area Male Health and Examination Survey cohort. RESULT: A total of 1999 subjects with 29 biochemical indices and 709,211 single nucleotide polymorphisms (SNPs) were subjected to phenomics analysis. Three bioinformatics methods, namely, Pearson's test, Jaccard's index, and linkage disequilibrium score regression, were used. The results showed that 29 biochemical indices were from a network. IgA, IgG, IgE, IgM, HCY, AFP and B12 were in the central community of 29 biochemical indices. Key genes and loci associated with metabolism traits were further identified, and shared genetics analysis showed that 29 SNPs (P < 10- 4) were associated with three or more traits. After integrating the SNPs related to two or more traits with the GWAS catalogue, 31 SNPs were found to be associated with several diseases (P < 10- 8). Using ALDH2 as an example to preliminarily explore its biological function, we also confirmed that the rs671 (ALDH2) polymorphism affected multiple traits of osteogenesis and adipogenesis differentiation in 3 T3-L1 preadipocytes. CONCLUSION: All these findings indicated a network of shared genetics and 29 biochemical indices, which will help fully understand the genetics participating in biochemical metabolism.


Subject(s)
Aldehyde Dehydrogenase, Mitochondrial/genetics , Phenomics/methods , Quantitative Trait Loci , 3T3-L1 Cells , Adult , Aged , Animals , Cell Differentiation , China , Genome-Wide Association Study , Humans , Linkage Disequilibrium , Male , Mice , Middle Aged , Polymorphism, Single Nucleotide , Young Adult
19.
J Gen Virol ; 100(2): 156-165, 2019 02.
Article in English | MEDLINE | ID: mdl-30484759

ABSTRACT

Classical swine fever virus (CSFV), the etiological agent of classical swine fever in pigs, is a member of the Pestivirus genus within the Flaviviridae family. It has been proposed that CSFV infection is significantly inhibited by methyl-ß-cyclodextrin (MßCD) treatment. However, the exact engagement of cellular cholesterol in the life cycle of CSFV remains unclear. Here, we demonstrated that pretreatment of PK-15 cells with MßCD significantly decreased the cellular cholesterol level and resulted in the inhibition of CSFV infection, while replenishment of exogenous cholesterol in MßCD-treated cells recovered the cellular cholesterol level and restored the viral infection. Moreover, we found that depletion of cholesterol acted on the early stage of CSFV infection and blocked its internalization into the host cells. Furthermore, we showed that 25-hydroxycholesterol, a regulator of cellular cholesterol biosynthesis, exhibited a potent anti-CSFV activity by reducing cellular cholesterol level. Taken together, our findings highlight the engagement of cholesterol in the life cycle of CSFV and its potential use as an antiviral target.


Subject(s)
Cholesterol/metabolism , Classical Swine Fever Virus/growth & development , Virus Internalization , Animals , Antiviral Agents/pharmacology , Cell Line , Epithelial Cells/drug effects , Epithelial Cells/virology , Hydroxycholesterols/pharmacology , Swine , beta-Cyclodextrins/metabolism
20.
J Virol ; 91(11)2017 06 01.
Article in English | MEDLINE | ID: mdl-28331099

ABSTRACT

Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), which poses a serious threat to the global pig industry. Interferons (IFNs) and IFN-stimulated genes (ISGs) play a key role in host antiviral defense. We have previously screened the porcine 2'-5'-oligoadenylate synthetase-like protein (pOASL) as a potential anti-CSFV ISG using a reporter CSFV. This study aimed to clarify the underlying antiviral mechanism of pOASL against CSFV. We confirmed that CSFV replication was significantly suppressed in lentivirus-delivered, pOASL-overexpressing PK-15 cells, whereas silencing the expression of endogenous pOASL by small interfering RNAs markedly enhanced CSFV growth. In addition, the transcriptional level of pOASL was upregulated both in vitro and in vivo upon CSFV infection. Interestingly, the anti-CSFV effects of pOASL are independent of the canonical RNase L pathway but depend on the activation of the type I IFN response. Glutathione S-transferase pulldown and coimmunoprecipitation assays revealed that pOASL interacts with MDA5, a double-stranded RNA sensor, and further enhances MDA5-mediated type I IFN signaling. Moreover, we showed that pOASL exerts anti-CSFV effects in an MDA5-dependent manner. In conclusion, pOASL suppresses CSFV replication via the MDA5-mediated type I IFN-signaling pathway.IMPORTANCE The host innate immune response plays an important role in mounting the initial resistance to viral infection. Here, we identify the porcine 2'-5'-oligoadenylate synthetase-like protein (pOASL) as an interferon (IFN)-stimulated gene (ISG) against classical swine fever virus (CSFV). We demonstrate that the anti-CSFV effects of pOASL depend on the activation of type I IFN response. In addition, we show that pOASL, as an MDA5-interacting protein, is a coactivator of MDA5-mediated IFN induction to exert anti-CSFV actions. This work will be beneficial to the development of novel anti-CSFV strategies by targeting pOASL.


Subject(s)
2',5'-Oligoadenylate Synthetase/metabolism , Classical Swine Fever Virus/physiology , Host-Pathogen Interactions , Interferon Type I/metabolism , Interferon-Induced Helicase, IFIH1/metabolism , Animals , Cell Line , Classical Swine Fever/immunology , Classical Swine Fever/virology , Classical Swine Fever Virus/growth & development , Endoribonucleases/genetics , Endoribonucleases/metabolism , Glutathione Transferase/metabolism , Immunity, Innate , Immunoprecipitation , Interferon Type I/genetics , Interferon Type I/immunology , Interferon-Induced Helicase, IFIH1/genetics , Interferon-Induced Helicase, IFIH1/immunology , RNA, Small Interfering/genetics , Signal Transduction , Swine , Virus Replication
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