Host interferon-stimulated gene 20(ISG20)exerts antiviral effects on viruses by degrading viral RNA or by enhancing IFN signaling.Here,we examined the role of ISG20 during pseudorabies virus(PRV)proliferation.We found...Host interferon-stimulated gene 20(ISG20)exerts antiviral effects on viruses by degrading viral RNA or by enhancing IFN signaling.Here,we examined the role of ISG20 during pseudorabies virus(PRV)proliferation.We found that ISG20 modulates PRV replication by enhancing IFN signaling.Further,ISG20 expression was upregulated following PRV infection and poly(I:C)treatment.Ectopic expression of ISG20 inhibited PRV proliferation in PK15 cells,whereas knockdown of ISG20 promoted PRV proliferation.In addition,ISG20 expression upregulated IFN-βexpression and enhanced IFN downstream signaling during PRV infection.Notably,PRV UL24 suppressed the transcription of ISG20,thus antagonizing its antiviral effect.Further domain mapping analysis showed that the N terminus(amino acids 1-90)of UL24 was responsible for the inhibition of ISG20 transcription.Collectively,these findings characterize the role of ISG20 in suppressing PRV replication and increase the understanding of host-PRV interplay.展开更多
Cholesterol-25-hydroxylase(CH25H)has been identified as an interferon-stimulated gene(ISG)in mammals that exerts its antiviral effects by catalyzing the conversion of cholesterol to 25-hydroxycholesterol(25HC).However...Cholesterol-25-hydroxylase(CH25H)has been identified as an interferon-stimulated gene(ISG)in mammals that exerts its antiviral effects by catalyzing the conversion of cholesterol to 25-hydroxycholesterol(25HC).However,invertebrates lack an antiviral system homologous to vertebrate interferons(IFNs)because the genomes of invertebrates do not encode IFN-like cytokines.Nevertheless,CH25H is present in insect genomes and it therefore deserves further study of whether and by which mechanism it could exert an antiviral effect in invertebrates.In this study,the Bombyx mori CH25H(BmCH25H)gene,of which the encoded protein has high homology with other lepidopteran species,was identified and located on chromosome 9.Interestingly,we found that the expression of BmCH25H was significantly upregulated in B.mori nucleopolyhedrovirus(BmNPV)-infected BmN cells and silkworm(B.mori)larvae at the early infection stage.The inhibitory effect of BmCH25H on BmNPV replication was further demonstrated to depend on its catalytic residues to convert cholesterol to 25HC.More importantly,we demonstrated that during BmNPV infection,BmCH25H expression was increased through the Janus kinase–signal transducer and activator of transcription(JAK–STAT)pathway,similar to the induction of ISGs following virus infection in vertebrates.This is the first report that CH25H has antiviral effects in insects;the study also elucidates the regulation of its expression and its mechanism of action.展开更多
ISG20 is an interferon-inducible exonuclease that inhibits virus replication.Although ISG20 is thought to degrade viral RNA,the antiviral mechanism and specificity of ISG20 remain unclear.In this study,the antiviral r...ISG20 is an interferon-inducible exonuclease that inhibits virus replication.Although ISG20 is thought to degrade viral RNA,the antiviral mechanism and specificity of ISG20 remain unclear.In this study,the antiviral role of ovine ISG20(o ISG20)in bluetongue virus(BTV)infection was investigated.It was found that BTV infection upregulated the transcription of ovine ISG20(o ISG20)in a time-and BTV multiplicity of infection(MOI)-dependent manner.Overexpression of o ISG20 suppressed the production of BTV genome,proteins,and virus titer,whereas the knockdown of o ISG20 increased viral replication.o ISG20 was found to co-localize with BTV proteins VP4,VP5,VP6,and NS2,but only directly interacted with VP4.Exonuclease defective o ISG20 significantly decreased the inhibitory effect on BTV replication.In addition,the interaction of mutant o ISG20 and VP4 was weakened,suggesting that binding to VP4 was associated with the inhibition of BTV replication.The present data characterized the anti-BTV effect of o ISG20,and provides a novel clue for further exploring the inhibition mechanism of double-stranded RNA virus by ISG20.展开更多
AIM To assess the effects of hepatitis E virus(HEV) on the production of type Ⅰ interferons(IFNs) and determine the underlying mechanisms.METHODS We measured the production of interferon(IFN)-alpha and-beta(-α/β) i...AIM To assess the effects of hepatitis E virus(HEV) on the production of type Ⅰ interferons(IFNs) and determine the underlying mechanisms.METHODS We measured the production of interferon(IFN)-alpha and-beta(-α/β) in genotype 3 HEV-infected C3 A cells at different time points(0, 8, 12, 24, 48, 72 and 120 h) by enzyme-linked immunosorbent assay(ELISA). The expression levels of IFN-stimulated gene(ISG)15 in HEVinfected C3A cells at different time points were tested by western blotting. The plasmid-expressing open reading frame 3(ORF3) or control plasmids(green fluorescent protein-expressing) were transfected into C3A cells, and the levels of IFN-α/β and ISG15 were evaluated, respectively. Furthermore, the plasmid-expressing ISG15 or small interfering RNA-inhibiting ISG15 was transfected into infected C3A cells. Then, the production of IFN-α/β was also measured by ELISA.RESULTS We showed that genotype 3 HEV could enhance the production of IFN-α/β and induce elevation of ISG15 in C3A cells. HEV ORF3 protein could enhance the production of IFN-α/β and the expression of ISG15. Additionally, ISG15 silencing enhanced the production of IFN-α/β. Overexpression of ISG15 resulted in the reduction of IFN-α/β.CONCLUSION HEV may promote production of IFN-α/β and expression of ISG15 via ORF3 in the early stages, and increased ISG15 subsequently inhibited the production of IFN-α/β.展开更多
Avian leukosis(AL)is a general term for a variety of neoplastic diseases in avian caused by avian leukosis virus(ALV).No vaccine or drug is currently available for the disease.Therefore,the disease can result in sever...Avian leukosis(AL)is a general term for a variety of neoplastic diseases in avian caused by avian leukosis virus(ALV).No vaccine or drug is currently available for the disease.Therefore,the disease can result in severe economic losses in poultry flocks.Increasing the resistance of poultry to ALV may be one effective strategy.In this review,we provide an overview of the roles of genes associated with ALV infection in the poultry genome,including endogenous retroviruses,virus receptors,interferon-stimulated genes,and other immune-related genes.Furthermore,some methods and techniques that can improve ALV resistance in poultry are discussed.The objectives are willing to provide some valuable references for disease resistance breeding in poultry.展开更多
Zika virus(ZIKV) infection can cause severe neurological diseases including neonatal microcephaly and GuillainBarre syndrome. Long noncoding RNAs(lncRNAs) are the by-products of the transcription process, which are co...Zika virus(ZIKV) infection can cause severe neurological diseases including neonatal microcephaly and GuillainBarre syndrome. Long noncoding RNAs(lncRNAs) are the by-products of the transcription process, which are considered to affect viral infection. However, it remains largely unexplored whether host lncRNAs play a role in ZIKV infection. Here, we identified a group of human lncRNAs that were up-regulated upon ZIKV infection and were dependent on the type I interferon(IFN) signaling. Overexpression of lncRNA ZAP-IT1 leads to an impairment of ZIKV infection. Correspondently, deficiency of ZAP-IT1 led to an enhancement of ZIKV infection.We further confirmed that ZAP-IT1, an intronic lncRNA with total 551 nt in length, is mainly located in the nuclear upon ZIKV infection. Knockout of ZAP-IT1 also led to the increase of dengue virus(DENV), Japanese encephalitis virus(JEV), or vesicular stomatitis virus(VSV) infection. Mechanically, we found that the antiviral effect of ZAP-IT1 was independent of the type I IFN signaling pathway. Therefore, our data unveiled that host lncRNA ZAP-IT1 induced by the type I IFN signaling, showed robust restriction on ZIKV infection, and even on DENV, JEV, and VSV infection, which may benefit the development of antiviral therapeutics.展开更多
Human endogenous retroviruses(HERVs) are the remains of ancient retroviruses that invaded our ancestors’ germline cell and were integrated into the genome. The expression of HERVs has always been a cause for concern ...Human endogenous retroviruses(HERVs) are the remains of ancient retroviruses that invaded our ancestors’ germline cell and were integrated into the genome. The expression of HERVs has always been a cause for concern because of its association with various cancers and diseases. However, few previous studies have focused on specific activation of HERVs by viral infections. Our previous study has shown that dengue virus type 2(DENV-2) infection induces the transcription of a large number of abnormal HERVs loci;therefore, the purpose of this study was to explore the relationship between exogenous viral infection and HERV activation further. In this study, we retrieved and reanalyzed published data on 21 transcriptomes of human cells infected with various viruses. We found that infection with different viruses could induce transcriptional activation of HERV loci. Through the comparative analysis of all viral datasets, we identified 43 key HERV loci that were up-regulated by DENV-2, influenza A virus, influenza B virus, Zika virus, measles virus, and West Nile virus infections. Furthermore, the neighboring genes of these HERVs were simultaneously up-regulated, and almost all such neighboring genes were interferon-stimulated genes(ISGs), which are enriched in the host’s antiviral immune response pathways. Our data supported the hypothesis that activation of HERVs, probably via an interferon-mediated mechanism, plays an important role in innate immunity against viral infections.展开更多
Introduction:Verruca vulgaris is one of the most common low-risk HPV infections and is characterized by excessive proliferation of keratinocytes.Currently,very little genetic information is available regarding verruca...Introduction:Verruca vulgaris is one of the most common low-risk HPV infections and is characterized by excessive proliferation of keratinocytes.Currently,very little genetic information is available regarding verruca vulgaris in the Chinese population.This study aimed to obtain comprehensive transcript information of verruca vulgaris by RNA sequencing.Methods:High-throughput sequencing was performed on three fresh verruca vulgaris samples and adjacent normal skin on the Illumina sequencing platform.The transcriptomes were analyzed using bioinformatics and the differentially expressed genes(DEGs)were verified by immunohistochemistry.Verruca vulgaris exhibited a unique molecular signature.Results:In total,1,643 DEGs were identified in verruca vulgaris compared to normal skin.The functions of the DEGs were studies by Gene Ontology(GO)enrichment,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis,DEGs Reactome analysis,disease annotation function,and STRING protein-protein interaction(PPI)network analysis.The results revealed 595 GO terms associated with the cell cycle,signal transduction,immune system,signaling molecules,and interaction.The Reactome analysis revealed enrichment in reversible hydration of carbon dioxide and BMP signaling,while the disease annotation function revealed that the enriched DEGs are involved in keratosis disorders.The STRING PPI network showed that the edges with the highest density mainly included the 2′-5′oligoadenylate synthase(OAS)family-related proteins.Furthermore,the M-code analysis found ISG15,IRF7,and OASL were scored as significant modules and their high expression compared to the control was verified by immunohistochemistry.Conclusion:These findings contribute to the genetic information of verruca vulgaris in the Chinese population,revealing that interferon-stimulated genes may play essential roles in verruca vulgaris.展开更多
TRIM25 is emerging as a central factor in breast cancer due to its regulation and function.In particular,it has been shown that:(1)Estrogens modulate TRIM25 gene expression;(2)TRIM25 has activity as an E3-ligase enzym...TRIM25 is emerging as a central factor in breast cancer due to its regulation and function.In particular,it has been shown that:(1)Estrogens modulate TRIM25 gene expression;(2)TRIM25 has activity as an E3-ligase enzyme for ubiquitin;and(3)TRIM25 is also an E3 ligase for interferon-stimulated gene 15 protein in the ISGylation system.Consequently,the proteome of mammary tissue is affected by TRIM25-associated pathways,involved in tumor development and metastasis.Here,we discuss the findings on the mechanisms involved in regulating TRIM25 expression and its functional relevance in breast cancer progression.These studies suggest that TRIM25 may be a biomarker and a therapeutic target for breast cancer.展开更多
Extensive studies on HIV-1 have led to the discovery of a variety of structurally and functionally diverse innate defense factors that target various steps of the retroviral replication cycle.Some of them,such as APOB...Extensive studies on HIV-1 have led to the discovery of a variety of structurally and functionally diverse innate defense factors that target various steps of the retroviral replication cycle.Some of them,such as APOBEC3,tetherin,and SERINC5,are well established.Their importance is evident from the fact that HIV-1 uses its accessory proteins Vif,Vpu,and Nef to counteract them.However,the list of antiviral factors is constantly increasing,and accumulating evidence suggests that innate defense mechanisms,which restrict HIV-1 and/or are counteracted by viral proteins,remain to be discovered.These antiviral factors are relevant to diseases other than HIV/AIDS,since they are commonly active against various viral pathogens.In this review,we provide an overview of recently reported antiretroviral factors and viral countermeasures,present the evidence suggesting that more innate defense mechanisms remain to be discovered,and discuss why this is a challenging but rewarding task.展开更多
Virus infection induces the production of type I interferons （IFNs）. IFNs bind to their heterodimeric receptors to initiate downstream cascade of signaling, leading to the up-regulation of interferon-stimulated gen...Virus infection induces the production of type I interferons （IFNs）. IFNs bind to their heterodimeric receptors to initiate downstream cascade of signaling, leading to the up-regulation of interferon-stimulated genes （ISGs）. ISGs play very important roles in innate immunity through a variety of mechanisms. Although hundreds of ISGs have been identified, it is commonly recognized that more ISGs await to be discovered. The aim of this study was to identify new ISGs and to probe their roles in regulating virus-induced type I IFN production. We used consensus interferon （Con-IFN）, an artificial alpha IFN that was shown to be more potent than naturally existing type I IFN, to treat three human immune cell lines, CEM, U937 and Daudi cells. Microarray analysis was employed to identify those genes whose expres- sions were up-regulated. Six hundred and seventeen genes were up-regulated more than 3-fold. Out of these 617 genes, 138 were not previously reported as ISGs and thus were further pursued. Validation of these 138 genes using quantitative reverse transcription PCR （qRT-PCR） confirmed 91 genes. We screened 89 genes for those involved in Sendal virus （SeV）-induced IFN-13 promoter activation, and PIM1 was identified as one whose expression inhibited SeV-mediated IFN-β activation. We provide evidence indicating that PIM1 specifically inhibits RIG-I- and MDA5-mediated IFN-β signaling. Our results expand the ISG library and iden- tify PIM1 as an ISG that participates in the regulation of virus-induced type I interferon production.展开更多
In a recent genome-wide association study, single nucleotide polymorphisms (SNPs) located near the interleukin-28B gene (IL28B), which encodes type Ⅲ interferon (IFN) λ3, were shown to be strongly associated with a ...In a recent genome-wide association study, single nucleotide polymorphisms (SNPs) located near the interleukin-28B gene (IL28B), which encodes type Ⅲ interferon (IFN) λ3, were shown to be strongly associated with a viral response to pegylated IFNα (PEG-IFNα) and ribavirin (RBV) combination therapy and spontaneous viral clearance in patients chroni-cally and acutely infected with hepatitis C virus (HCV), respectively. The global distribution of allele frequencies shows a remarkable pattern, in which a favorable allele is nearly fixed in East Asia, has an intermediate frequency in Europe, and is least frequent in Africa. Although the under-lying mechanisms responsible for viral responses associated with IL28B SNPs have not been completely elucidated, IFN-stimulated gene expression in patients with unfavorable IL28B genotypes tends to be high at baseline and is insufficiently induced by exogenous IFN administration, resulting in poor treatment outcomes. Clinically, triple therapy with PEG-IFNα/RBV together with direct-acting anti-viral agents (DAAs) is currently used to treat chronic hepatitis C as a first-line therapy. Although the predictive power of IL28B status may be attenuated, the IL28B genotype will remain relevant to the outcomes of DAA therapy when used in combination with PEG-IFNα as a backbone. Even with the introduction of IFN-free therapies with a new class of highly effective DAAs, IL28B SNPs are still useful predictors of treatment outcomes and can be used to individualize treat-ment strategies to maximize cost-effectiveness and identify patients at risk of being refractory to treatment. This review summarizes the current understanding of the clinical sig-nificance and role of IL28B in HCV infection and response to therapy.展开更多
基金supports from the National Key Research and Development Program of China(2016YFD0500100)Shanghai Science and Technology Innovation Action Plan(17391901900)Shanghai Municipal Agriculture Science and Technology Key Project(2016,4-2)。
文摘Host interferon-stimulated gene 20(ISG20)exerts antiviral effects on viruses by degrading viral RNA or by enhancing IFN signaling.Here,we examined the role of ISG20 during pseudorabies virus(PRV)proliferation.We found that ISG20 modulates PRV replication by enhancing IFN signaling.Further,ISG20 expression was upregulated following PRV infection and poly(I:C)treatment.Ectopic expression of ISG20 inhibited PRV proliferation in PK15 cells,whereas knockdown of ISG20 promoted PRV proliferation.In addition,ISG20 expression upregulated IFN-βexpression and enhanced IFN downstream signaling during PRV infection.Notably,PRV UL24 suppressed the transcription of ISG20,thus antagonizing its antiviral effect.Further domain mapping analysis showed that the N terminus(amino acids 1-90)of UL24 was responsible for the inhibition of ISG20 transcription.Collectively,these findings characterize the role of ISG20 in suppressing PRV replication and increase the understanding of host-PRV interplay.
基金supported by the Natural Science Foundation of Guangdong Basic and Applied Basic Research Fund(2022A1515012657)Guangzhou Science and Technology Plan Project(202002030218)+3 种基金National Natural Science Foundation of China(31872426)South China Agricultural University high-level talent launch projectGuangdong Provincial Promotion Project on Preservation and Utilization of Local Breed of Livestock and Poultry(No.2018-143)Innovation and Entrepreneurship Training Program for College Students in Guangdong Province(S202110564098).
文摘Cholesterol-25-hydroxylase(CH25H)has been identified as an interferon-stimulated gene(ISG)in mammals that exerts its antiviral effects by catalyzing the conversion of cholesterol to 25-hydroxycholesterol(25HC).However,invertebrates lack an antiviral system homologous to vertebrate interferons(IFNs)because the genomes of invertebrates do not encode IFN-like cytokines.Nevertheless,CH25H is present in insect genomes and it therefore deserves further study of whether and by which mechanism it could exert an antiviral effect in invertebrates.In this study,the Bombyx mori CH25H(BmCH25H)gene,of which the encoded protein has high homology with other lepidopteran species,was identified and located on chromosome 9.Interestingly,we found that the expression of BmCH25H was significantly upregulated in B.mori nucleopolyhedrovirus(BmNPV)-infected BmN cells and silkworm(B.mori)larvae at the early infection stage.The inhibitory effect of BmCH25H on BmNPV replication was further demonstrated to depend on its catalytic residues to convert cholesterol to 25HC.More importantly,we demonstrated that during BmNPV infection,BmCH25H expression was increased through the Janus kinase–signal transducer and activator of transcription(JAK–STAT)pathway,similar to the induction of ISGs following virus infection in vertebrates.This is the first report that CH25H has antiviral effects in insects;the study also elucidates the regulation of its expression and its mechanism of action.
基金the National Key Research and Development Program of China(2021YFD18005022017YFD0502304)+2 种基金National Natural Science Foundation of China(31672562)NBCITS(CARS-37)ASTIP(CAAS-ASTIP-2016-LVRI)。
文摘ISG20 is an interferon-inducible exonuclease that inhibits virus replication.Although ISG20 is thought to degrade viral RNA,the antiviral mechanism and specificity of ISG20 remain unclear.In this study,the antiviral role of ovine ISG20(o ISG20)in bluetongue virus(BTV)infection was investigated.It was found that BTV infection upregulated the transcription of ovine ISG20(o ISG20)in a time-and BTV multiplicity of infection(MOI)-dependent manner.Overexpression of o ISG20 suppressed the production of BTV genome,proteins,and virus titer,whereas the knockdown of o ISG20 increased viral replication.o ISG20 was found to co-localize with BTV proteins VP4,VP5,VP6,and NS2,but only directly interacted with VP4.Exonuclease defective o ISG20 significantly decreased the inhibitory effect on BTV replication.In addition,the interaction of mutant o ISG20 and VP4 was weakened,suggesting that binding to VP4 was associated with the inhibition of BTV replication.The present data characterized the anti-BTV effect of o ISG20,and provides a novel clue for further exploring the inhibition mechanism of double-stranded RNA virus by ISG20.
基金Supported by the National Natural Science Foundation of China,No.81570540
文摘AIM To assess the effects of hepatitis E virus(HEV) on the production of type Ⅰ interferons(IFNs) and determine the underlying mechanisms.METHODS We measured the production of interferon(IFN)-alpha and-beta(-α/β) in genotype 3 HEV-infected C3 A cells at different time points(0, 8, 12, 24, 48, 72 and 120 h) by enzyme-linked immunosorbent assay(ELISA). The expression levels of IFN-stimulated gene(ISG)15 in HEVinfected C3A cells at different time points were tested by western blotting. The plasmid-expressing open reading frame 3(ORF3) or control plasmids(green fluorescent protein-expressing) were transfected into C3A cells, and the levels of IFN-α/β and ISG15 were evaluated, respectively. Furthermore, the plasmid-expressing ISG15 or small interfering RNA-inhibiting ISG15 was transfected into infected C3A cells. Then, the production of IFN-α/β was also measured by ELISA.RESULTS We showed that genotype 3 HEV could enhance the production of IFN-α/β and induce elevation of ISG15 in C3A cells. HEV ORF3 protein could enhance the production of IFN-α/β and the expression of ISG15. Additionally, ISG15 silencing enhanced the production of IFN-α/β. Overexpression of ISG15 resulted in the reduction of IFN-α/β.CONCLUSION HEV may promote production of IFN-α/β and expression of ISG15 via ORF3 in the early stages, and increased ISG15 subsequently inhibited the production of IFN-α/β.
基金the National Natural Science Foundation of China(Grant Nos.31970540&31801030)the China Agriculture Research System of MOF and MARA(Grant No.CARS-41)the National Key R&D Program of China(Grant No.2021YFD1300100)。
文摘Avian leukosis(AL)is a general term for a variety of neoplastic diseases in avian caused by avian leukosis virus(ALV).No vaccine or drug is currently available for the disease.Therefore,the disease can result in severe economic losses in poultry flocks.Increasing the resistance of poultry to ALV may be one effective strategy.In this review,we provide an overview of the roles of genes associated with ALV infection in the poultry genome,including endogenous retroviruses,virus receptors,interferon-stimulated genes,and other immune-related genes.Furthermore,some methods and techniques that can improve ALV resistance in poultry are discussed.The objectives are willing to provide some valuable references for disease resistance breeding in poultry.
基金supported by National Natural Science Foundation of China,China(No.31970887)Guangdong Science and Technology Department,China(No.2018B030337001)Guangdong Basic and Applied Basic Foundation(No.2019A1515011336)
文摘Zika virus(ZIKV) infection can cause severe neurological diseases including neonatal microcephaly and GuillainBarre syndrome. Long noncoding RNAs(lncRNAs) are the by-products of the transcription process, which are considered to affect viral infection. However, it remains largely unexplored whether host lncRNAs play a role in ZIKV infection. Here, we identified a group of human lncRNAs that were up-regulated upon ZIKV infection and were dependent on the type I interferon(IFN) signaling. Overexpression of lncRNA ZAP-IT1 leads to an impairment of ZIKV infection. Correspondently, deficiency of ZAP-IT1 led to an enhancement of ZIKV infection.We further confirmed that ZAP-IT1, an intronic lncRNA with total 551 nt in length, is mainly located in the nuclear upon ZIKV infection. Knockout of ZAP-IT1 also led to the increase of dengue virus(DENV), Japanese encephalitis virus(JEV), or vesicular stomatitis virus(VSV) infection. Mechanically, we found that the antiviral effect of ZAP-IT1 was independent of the type I IFN signaling pathway. Therefore, our data unveiled that host lncRNA ZAP-IT1 induced by the type I IFN signaling, showed robust restriction on ZIKV infection, and even on DENV, JEV, and VSV infection, which may benefit the development of antiviral therapeutics.
基金This work was supported by the China Ministry of Science and Technology Key Research&Development Program(No.2016YFC1200800)the National Natural Science Foundation of China(No.91631110)the National Mega Project on Major Infectious Disease Prevention(No.2017ZX10103005-005)。
文摘Human endogenous retroviruses(HERVs) are the remains of ancient retroviruses that invaded our ancestors’ germline cell and were integrated into the genome. The expression of HERVs has always been a cause for concern because of its association with various cancers and diseases. However, few previous studies have focused on specific activation of HERVs by viral infections. Our previous study has shown that dengue virus type 2(DENV-2) infection induces the transcription of a large number of abnormal HERVs loci;therefore, the purpose of this study was to explore the relationship between exogenous viral infection and HERV activation further. In this study, we retrieved and reanalyzed published data on 21 transcriptomes of human cells infected with various viruses. We found that infection with different viruses could induce transcriptional activation of HERV loci. Through the comparative analysis of all viral datasets, we identified 43 key HERV loci that were up-regulated by DENV-2, influenza A virus, influenza B virus, Zika virus, measles virus, and West Nile virus infections. Furthermore, the neighboring genes of these HERVs were simultaneously up-regulated, and almost all such neighboring genes were interferon-stimulated genes(ISGs), which are enriched in the host’s antiviral immune response pathways. Our data supported the hypothesis that activation of HERVs, probably via an interferon-mediated mechanism, plays an important role in innate immunity against viral infections.
基金The National Natural Science Foundation of China(Grant No.81903227)supported our study.
文摘Introduction:Verruca vulgaris is one of the most common low-risk HPV infections and is characterized by excessive proliferation of keratinocytes.Currently,very little genetic information is available regarding verruca vulgaris in the Chinese population.This study aimed to obtain comprehensive transcript information of verruca vulgaris by RNA sequencing.Methods:High-throughput sequencing was performed on three fresh verruca vulgaris samples and adjacent normal skin on the Illumina sequencing platform.The transcriptomes were analyzed using bioinformatics and the differentially expressed genes(DEGs)were verified by immunohistochemistry.Verruca vulgaris exhibited a unique molecular signature.Results:In total,1,643 DEGs were identified in verruca vulgaris compared to normal skin.The functions of the DEGs were studies by Gene Ontology(GO)enrichment,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis,DEGs Reactome analysis,disease annotation function,and STRING protein-protein interaction(PPI)network analysis.The results revealed 595 GO terms associated with the cell cycle,signal transduction,immune system,signaling molecules,and interaction.The Reactome analysis revealed enrichment in reversible hydration of carbon dioxide and BMP signaling,while the disease annotation function revealed that the enriched DEGs are involved in keratosis disorders.The STRING PPI network showed that the edges with the highest density mainly included the 2′-5′oligoadenylate synthase(OAS)family-related proteins.Furthermore,the M-code analysis found ISG15,IRF7,and OASL were scored as significant modules and their high expression compared to the control was verified by immunohistochemistry.Conclusion:These findings contribute to the genetic information of verruca vulgaris in the Chinese population,revealing that interferon-stimulated genes may play essential roles in verruca vulgaris.
文摘TRIM25 is emerging as a central factor in breast cancer due to its regulation and function.In particular,it has been shown that:(1)Estrogens modulate TRIM25 gene expression;(2)TRIM25 has activity as an E3-ligase enzyme for ubiquitin;and(3)TRIM25 is also an E3 ligase for interferon-stimulated gene 15 protein in the ISGylation system.Consequently,the proteome of mammary tissue is affected by TRIM25-associated pathways,involved in tumor development and metastasis.Here,we discuss the findings on the mechanisms involved in regulating TRIM25 expression and its functional relevance in breast cancer progression.These studies suggest that TRIM25 may be a biomarker and a therapeutic target for breast cancer.
基金supported by the Deutsche Forschungsgemeinschaft(CRC 1279)supported by a‘Bausteinprogramm’grant from Ulm University Medical Center,Else Kröner Fresenius Stiftung(2022_EKEA.47)European Union's Horizon 2020 Marie Sklodowska-Curie program(no.101062524).
文摘Extensive studies on HIV-1 have led to the discovery of a variety of structurally and functionally diverse innate defense factors that target various steps of the retroviral replication cycle.Some of them,such as APOBEC3,tetherin,and SERINC5,are well established.Their importance is evident from the fact that HIV-1 uses its accessory proteins Vif,Vpu,and Nef to counteract them.However,the list of antiviral factors is constantly increasing,and accumulating evidence suggests that innate defense mechanisms,which restrict HIV-1 and/or are counteracted by viral proteins,remain to be discovered.These antiviral factors are relevant to diseases other than HIV/AIDS,since they are commonly active against various viral pathogens.In this review,we provide an overview of recently reported antiretroviral factors and viral countermeasures,present the evidence suggesting that more innate defense mechanisms remain to be discovered,and discuss why this is a challenging but rewarding task.
基金We thank Dr. Hongbing Shu for providing IFN-β-1uc reporter, pTK- renilla, Flag-tagged RIG-I, MDA5, VISA, TBK1 and IKKE vectors, Dr. Zhengfan Jiang for Sendai virus （SeV）. We thank Zhimin Wang, Xudong Zhao and Xiaofei Guo of the core facility of the Institute of Biophysics, CAS, for technical assistance. This work was supported by grants to Guangxia Gao from Chinese Academy of Sciences （KFZD-SW-209） and National Natural Science Foundation of China （Grant No. 81530066）.
文摘Virus infection induces the production of type I interferons （IFNs）. IFNs bind to their heterodimeric receptors to initiate downstream cascade of signaling, leading to the up-regulation of interferon-stimulated genes （ISGs）. ISGs play very important roles in innate immunity through a variety of mechanisms. Although hundreds of ISGs have been identified, it is commonly recognized that more ISGs await to be discovered. The aim of this study was to identify new ISGs and to probe their roles in regulating virus-induced type I IFN production. We used consensus interferon （Con-IFN）, an artificial alpha IFN that was shown to be more potent than naturally existing type I IFN, to treat three human immune cell lines, CEM, U937 and Daudi cells. Microarray analysis was employed to identify those genes whose expres- sions were up-regulated. Six hundred and seventeen genes were up-regulated more than 3-fold. Out of these 617 genes, 138 were not previously reported as ISGs and thus were further pursued. Validation of these 138 genes using quantitative reverse transcription PCR （qRT-PCR） confirmed 91 genes. We screened 89 genes for those involved in Sendal virus （SeV）-induced IFN-13 promoter activation, and PIM1 was identified as one whose expression inhibited SeV-mediated IFN-β activation. We provide evidence indicating that PIM1 specifically inhibits RIG-I- and MDA5-mediated IFN-β signaling. Our results expand the ISG library and iden- tify PIM1 as an ISG that participates in the regulation of virus-induced type I interferon production.
文摘In a recent genome-wide association study, single nucleotide polymorphisms (SNPs) located near the interleukin-28B gene (IL28B), which encodes type Ⅲ interferon (IFN) λ3, were shown to be strongly associated with a viral response to pegylated IFNα (PEG-IFNα) and ribavirin (RBV) combination therapy and spontaneous viral clearance in patients chroni-cally and acutely infected with hepatitis C virus (HCV), respectively. The global distribution of allele frequencies shows a remarkable pattern, in which a favorable allele is nearly fixed in East Asia, has an intermediate frequency in Europe, and is least frequent in Africa. Although the under-lying mechanisms responsible for viral responses associated with IL28B SNPs have not been completely elucidated, IFN-stimulated gene expression in patients with unfavorable IL28B genotypes tends to be high at baseline and is insufficiently induced by exogenous IFN administration, resulting in poor treatment outcomes. Clinically, triple therapy with PEG-IFNα/RBV together with direct-acting anti-viral agents (DAAs) is currently used to treat chronic hepatitis C as a first-line therapy. Although the predictive power of IL28B status may be attenuated, the IL28B genotype will remain relevant to the outcomes of DAA therapy when used in combination with PEG-IFNα as a backbone. Even with the introduction of IFN-free therapies with a new class of highly effective DAAs, IL28B SNPs are still useful predictors of treatment outcomes and can be used to individualize treat-ment strategies to maximize cost-effectiveness and identify patients at risk of being refractory to treatment. This review summarizes the current understanding of the clinical sig-nificance and role of IL28B in HCV infection and response to therapy.
