Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
PLoS Pathog ; 19(6): e1011443, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37327222

RESUMO

The host always employs various ways to defend against viral infection and spread. However, viruses have evolved their own effective strategies, such as inhibition of RNA translation of the antiviral effectors, to destroy the host's defense barriers. Protein synthesis, commonly controlled by the α-subunit of eukaryotic translation initiation factor 2 (eIF2α), is a basic cellular biological process among all species. In response to viral infection, in addition to inducing the transcription of antiviral cytokines by innate immunity, infected cells also inhibit the RNA translation of antiviral factors by activating the protein kinase R (PKR)-eIF2α signaling pathway. Regulation of innate immunity has been well studied; however, regulation of the PKR-eIF2α signaling pathway remains unclear. In this study, we found that the E3 ligase TRIM21 negatively regulates the PKR-eIF2α signaling pathway. Mechanistically, TRIM21 interacts with the PKR phosphatase PP1α and promotes K6-linked polyubiquitination of PP1α. Ubiquitinated PP1α augments its interaction with PKR, causing PKR dephosphorylation and subsequent translational inhibition release. Furthermore, TRIM21 can constitutively restrict viral infection by reversing PKR-dependent translational inhibition of various previously known and unknown antiviral factors. Our study highlights a previously undiscovered role of TRIM21 in regulating translation, which will provide new insights into the host antiviral response and novel targets for the treatment of translation-associated diseases in the clinic.


Assuntos
RNA , Viroses , Humanos , RNA/metabolismo , eIF-2 Quinase/metabolismo , Processamento de Proteína Pós-Traducional , Fosforilação , Antivirais , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Replicação Viral
2.
J Virol ; 97(12): e0151323, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38032198

RESUMO

IMPORTANCE: The precise regulation of the innate immune response is essential for the maintenance of homeostasis. MAVS and STING play key roles in immune signaling pathways activated by RNA and DNA viruses, respectively. Here, we showed that DHCR24 impaired the antiviral response by targeting MAVS and STING. Notably, DHCR24 interacts with MAVS and STING and inhibits TRIM21-triggered K27-linked ubiquitination of MAVS and AMFR-triggered K27-linked ubiquitination of STING, restraining the activation of MAVS and STING, respectively. Together, this study elucidates how one cholesterol key enzyme orchestrates two antiviral signal transduction pathways.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Imunidade Inata , Proteínas de Membrana , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Animais , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Hidroxiesteroides , Proteínas de Membrana/metabolismo , Oxirredutases , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Ubiquitinação , Linhagem Celular
3.
J Immunol ; 209(10): 1987-1998, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36426955

RESUMO

Pyroptosis is a form of regulated cell death mediated by the gasdermin protein family. During virus infection, cell pyroptosis restricts viral replication. The mechanisms of the tripartite motif (TRIM) protein family and IFN-stimulated genes (ISGs) against viruses have been studied. The role of TRIMs and ISGs in pyroptosis remains unclear. In this study, we show that TRIM21 interacts with ISG12a in viral infection and facilitates its translocation into the mitochondria by promoting its ubiquitination, thereby causing caspase 3 activation. Gasdermin E (GSDME) is specifically cleaved by caspase 3 upon viral infection, releasing the GSDME N-terminal domain, perforating the cell membrane, and causing cell pyroptosis. Our study uncovers a new mechanism of TRIM21 and ISG12a in regulating virus-induced cell pyroptosis.


Assuntos
Piroptose , Vírus , Piroptose/fisiologia , Caspase 3/metabolismo , Ubiquitinação , Morte Celular , Proteínas com Motivo Tripartido/metabolismo
4.
Development ; 147(20)2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-32820022

RESUMO

Seipin, an evolutionary conserved protein, plays pivotal roles during lipid droplet (LD) biogenesis and is associated with various human diseases with unclear mechanisms. Here, we analyzed Caenorhabditis elegans mutants deleted of the sole SEIPIN gene, seip-1 Homozygous seip-1 mutants displayed penetrant embryonic lethality, which is caused by the disruption of the lipid-rich permeability barrier, the innermost layer of the C. elegans embryonic eggshell. In C. elegans oocytes and embryos, SEIP-1 is associated with LDs and is crucial for controlling LD size and lipid homeostasis. The seip-1 deletion mutants reduced the ratio of polyunsaturated fatty acids (PUFAs) in their embryonic fatty acid pool. Interestingly, dietary supplementation of selected n-6 PUFAs rescued the embryonic lethality and defective permeability barrier. Accordingly, we propose that SEIP-1 may maternally regulate LD biogenesis and lipid homeostasis to orchestrate the formation of the permeability barrier for eggshell synthesis during embryogenesis. A lipodystrophy allele of seip-1 resulted in embryonic lethality as well and could be rescued by PUFA supplementation. These experiments support a great potential for using C. elegans to model SEIPIN-associated human diseases.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Casca de Ovo/embriologia , Genes de Helmintos , Proteínas de Membrana/genética , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/ultraestrutura , Proteínas de Caenorhabditis elegans/metabolismo , Suplementos Nutricionais , Modelos Animais de Doenças , Casca de Ovo/efeitos dos fármacos , Casca de Ovo/ultraestrutura , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/ultraestrutura , Ácidos Graxos Insaturados/farmacologia , Fertilização , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/ultraestrutura , Lipidômica , Proteínas de Membrana/metabolismo , Mutação/genética , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Oócitos/ultraestrutura , Ovulação/efeitos dos fármacos , Permeabilidade , Saccharomyces cerevisiae/genética
5.
J Virol ; 96(7): e0020722, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35297670

RESUMO

Long noncoding RNAs (lncRNAs) widely exist in the cells and play important roles in various biological processes. The role of lncRNAs in immunity remains largely unknown. lncRNA BST2-2 (lncBST2-2) was upregulated upon viral infection and dependent on the interferon (IFN)/JAK/STAT signaling pathway. There was no coding potential found in the lncBST2-2 transcript. Overexpression of lncBST2-2 inhibited the replication of hepatitis C virus (HCV), Newcastle disease virus (NDV), vesicular stomatitis virus (VSV), and herpes simplex virus (HSV), while knockdown of lncBST2-2 facilitated viral replication. Further studies showed that lncBST2-2 promoted the phosphorylation, dimerization, and nuclear transport of IRF3, promoting the production of IFNs. Importantly, lncBST2-2 interacted with the DNA-binding domain of IRF3, which augmented TBK1 and IRF3 interaction, thereby inducing robust production of IFNs. Moreover, lncBST2-2 impaired the interaction between IRF3 and PP2A-RACK1 complex, an essential step for the dephosphorylation of IRF3. These data shown that lncBST2-2 promotes the innate immune response to viral infection through targeting IRF3. Our study reveals the lncRNA involved in the activation of IRF3 and provides a new insight into the role of lncRNA in antiviral innate immunity. IMPORTANCE Innate immunity is an important part of the human immune system to resist the invasion of foreign pathogens. IRF3 plays a critical role in the innate immune response to viral infection. In this study, we demonstrated that lncBST2-2 plays an important role in innate immunity. Virus-induced lncBST2-2 positively regulates innate immunity by interacting with IRF3 and blocking the dephosphorylation effect of RACK1-PP2A complex on IRF3, thus inhibiting viral infection. Our study provides a new insight into the role of lncBST2-2 in the regulation of IRF3 signaling activation.


Assuntos
Interações Hospedeiro-Patógeno , Imunidade Inata , RNA Longo não Codificante , Viroses , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/genética , Fator Regulador 3 de Interferon/metabolismo , Interferons/metabolismo , RNA Longo não Codificante/genética , Viroses/genética , Viroses/imunologia , Replicação Viral , Vírus/imunologia
6.
J Virol ; 96(7): e0000122, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35254105

RESUMO

The induction of interferons (IFNs) plays an important role in the elimination of invading pathogens. Heat shock binding protein 21 (HBP21), first known as a molecular chaperone of HSP70, is involved in tumor development. Heat shock binding proteins have been shown to regulate diverse biological processes, such as cell cycle, kinetochore localization, transcription, and cilium formation. Their role in antimicrobial immunity remains unknown. Here, we found that HBP21 drives a positive feedback loop to promote IRF3-mediated IFN production triggered by viral infection. HBP21 deficiency significantly impaired the virus-induced production of IFN and resulted in greater susceptibility to viral infection both in vitro and in vivo. Mechanistically, HBP21 interacted with IRF3 and promoted the formation of a TBK1-IRF3 complex. Moreover, HBP21 abolished the interaction between PP2A and IRF3 to repress the dephosphorylation of IRF3. Analysis of HBP21 protein structure further confirmed that HBP21 promotes the activation of IRF3 by depressing the dephosphorylation of IRF3 by PP2A. Further study demonstrated that virus-induced phosphorylation of Ser85 and Ser153 of HBP21 itself is important for the phosphorylation and dimerization of IRF3. Our study identifies HBP21 as a new positive regulator of innate antiviral response, which adds novel insight into activation of IRF3 controlled by multiple networks that specify behavior of tumors and immunity. IMPORTANCE The innate immune system is the first-line host defense against microbial pathogen invasion. The physiological functions of molecular chaperones, involving cell differentiation, migration, proliferation and inflammation, have been intensively studied. HBP21 as a molecular chaperone is critical for tumor development. Tumor is related to immunity. Whether HBP21 regulates immunity remains unknown. Here, we found that HBP21 promotes innate immunity response by dual regulation of IRF3. HBP21 interacts with IRF3 and promotes the formation of a TBK1-IRF3 complex. Moreover, HBP21 disturbs the interaction between PP2A and IRF3 to depress the dephosphorylation of IRF3. Analysis of HBP21 protein structure confirms that HBP21 promotes the activation of IRF3 by blocking the dephosphorylation of IRF3 by PP2A. Interestingly, virus-induced Ser85 and Ser153 phosphorylation of HBP21 is important for IRF3 activation. Our findings add to the known novel immunological functions of molecular chaperones and provide new insights into the regulation of innate immunity.


Assuntos
Imunidade Inata , Chaperonas Moleculares , Viroses , Humanos , Imunidade Inata/genética , Imunidade Inata/imunologia , Fator Regulador 3 de Interferon/metabolismo , Chaperonas Moleculares/metabolismo , Fosforilação , Viroses/imunologia
7.
J Virol ; 96(6): e0217521, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35107381

RESUMO

REC8 meiotic recombination protein (REC8) is a member of structural maintenance of chromosome (SMC) protein partners, which play an important role in meiosis, antitumor activity, and sperm formation. As the adaptor proteins of RIG-I-like receptor (RLR) signaling and cyclic GMP-AMP synthase (cGAS)-DNA signaling, the activity and stability of MAVS (mitochondrial antiviral signaling protein; also known as VISA, Cardif, and IPS-1) and STING (stimulator of interferon genes; also known as MITA) are critical for innate immunity. Here, we report that REC8 interacts with MAVS and STING and inhibits their ubiquitination and subsequent degradation, thereby promoting innate antiviral signaling. REC8 is upregulated through the JAK-STAT signaling pathway during viral infection. Knockdown of REC8 impairs the innate immune responses against vesicular stomatitis virus (VSV), Newcastle disease virus (NDV), and herpes simplex virus (HSV). Mechanistically, during infection with viruses, the SUMOylated REC8 is transferred from the nucleus to the cytoplasm and then interacts with MAVS and STING to inhibit their K48-linked ubiquitination triggered by RNF5. Moreover, REC8 promotes the recruitment of TBK1 to MAVS and STING. Thus, REC8 functions as a positive modulator of innate immunity. Our work highlights a previously undocumented role of meiosis-associated protein REC8 in regulating innate immunity. IMPORTANCE The innate immune response is crucial for the host to resist the invasion of viruses and other pathogens. STING and MAVS play a critical role in the innate immune response to DNA and RNA viral infection, respectively. In this study, REC8 promoted the innate immune response by targeting STING and MAVS. Notably, REC8 interacts with MAVS and STING in the cytoplasm and inhibits K48-linked ubiquitination of MAVS and STING triggered by RNF5, stabilizing MAVS and STING protein to promote innate immunity and gradually inhibiting viral infection. Our study provides a new insight for the study of antiviral innate immunity.


Assuntos
Proteínas de Ciclo Celular , Imunidade Inata , Viroses , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Antivirais , Proteínas de Ciclo Celular/imunologia , Proteínas de Membrana/metabolismo , Vírus da Doença de Newcastle , Simplexvirus , Ubiquitinação , Vírus da Estomatite Vesicular Indiana , Viroses/imunologia
8.
Int J Mol Sci ; 24(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36768623

RESUMO

The detection of circulating tumor cells (CTCs) is an emerging strategy for the early detection, prognostication, and identification of recurrent cancer. The clinical utility of CTC detection has been established, but few studies have employed this strategy for the detection of gynecologic cancers. Here, we present a novel, biochip-based microfluidic device for the detection of CTCs in gynecologic cancers. The study cohort included three patients with cervical cancer, eight with endometrial cancer, two with ovarian cancer, two with breast cancer, and one with vaginal small cell carcinoma. Four cancer type-specific molecular markers (PanCK, GATA3, HER2, and HE4), as well as CD13, were used for prognostication and recurrence detection, along with downstream genomic analysis. GATA3 and HER2 were markedly expressed in the patients with cervical cancer, and this expression was strongly correlated with the early detection of recurrent disease. All four molecular markers were expressed preoperatively in the patients with endometrial cancer, and the re-expression of different markers was observed at follow-up before recurrence was confirmed. CD13 was identified as an alternative prognostic marker for both cervical and endometrial cancer. Our pilot study indicated that the novel CTC detection system can be used for prognostication and early detection of disease recurrence, which needed further investigation.


Assuntos
Neoplasias da Mama , Neoplasias do Endométrio , Neoplasias dos Genitais Femininos , Células Neoplásicas Circulantes , Neoplasias do Colo do Útero , Humanos , Feminino , Células Neoplásicas Circulantes/patologia , Microfluídica , Projetos Piloto , Recidiva Local de Neoplasia/diagnóstico , Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias da Mama/metabolismo , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Biomarcadores Tumorais
9.
Eur J Immunol ; 51(7): 1762-1773, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33811647

RESUMO

The type I interferon (IFN-I) system is important for antiviral and anticancer immunity. Prolonged activation of IFN/JAK/STAT signaling is closely associated with autoimmune diseases. TRIM10 dysfunction may be associated closely with certain autoimmune disorders. Here, we observed that the serum TRIM10 protein level is lower in patients with systemic lupus erythematosus than in healthy control subjects. We speculated the possible involvement of TRIM10-induced modulation of the IFN/JAK/STAT signaling pathway in systemic lupus erythematosus. In line with our hypothesis, TRIM10 inhibited the activation of JAK/STAT signaling pathway triggered by various stimuli. TRIM10 restricted the IFN-I/JAK/STAT signaling pathway, which was independent of its E3 ligase activity. Mechanistically, TRIM10 interacted with the intracellular domain of IFNAR1 and blocked the association of IFNAR1 with TYK2. These data suggest the possible TRIM10 suppresses IFN/JAK/STAT signaling pathway through blocking the interaction between IFNAR1 and TYK2. Targeting TRIM10 is a potential strategy for treating autoimmune diseases.


Assuntos
Interferon Tipo I/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Receptor de Interferon alfa e beta/metabolismo , Transdução de Sinais/fisiologia , Proteínas com Motivo Tripartido/metabolismo , Antivirais/farmacologia , Linhagem Celular , Feminino , Células HEK293 , Humanos , Fosforilação/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , TYK2 Quinase/metabolismo
10.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36499466

RESUMO

Single-cell sequencing provides promising information in tumor evolution and heterogeneity. Even with the recent advances in circulating tumor cell (CTC) technologies, it remains a big challenge to precisely and effectively isolate CTCs for downstream analysis. The Cell RevealTM system integrates an automatic CTC enrichment and staining machine, an AI-assisted automatic CTC scanning and identification system, and an automatic cell picking machine for CTC isolation. H1975 cell line was used for the spiking test. The identification of CTCs and the isolation of target CTCs for genetic sequencing were performed from the peripheral blood of three cancer patients, including two with lung cancer and one with both lung cancer and thyroid cancer. The spiking test revealed a mean recovery rate of 81.81% even with extremely low spiking cell counts with a linear relationship between the spiked cell counts and the recovered cell counts (Y = 0.7241 × X + 19.76, R2 = 0.9984). The three cancer patients had significantly higher TTF-1+ CTCs than healthy volunteers. All target CTCs were successfully isolated by the Cell Picker machine for a subsequent genetic analysis. Six tumor-associated mutations in four genes were detected. The present study reveals the Cell RevealTM platform can precisely identify and isolate target CTCs and then successfully perform single-cell sequencing by using commercially available genetic devices.


Assuntos
Neoplasias Pulmonares , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Separação Celular , Linhagem Celular Tumoral , Dispositivos Lab-On-A-Chip , Neoplasias Pulmonares/genética
11.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500559

RESUMO

A series of binary composites Bi4O5Br2/BiPO4 (PBX) was fabricated through a simple mechanical ball milling protocol. Relevant microstructural, morphological, and optical properties were thoroughly analyzed via various techniques. The integration of both components was confirmed to produce heterojunction domains at the phase boundaries. Upon exposure to visible light irradiation, the as-achieved PBX series possessed the reinforced photocatalytic NOx removal efficiencies and the weakened generation of toxic intermediate NO2 in comparison to both bare components, chiefly attributed to the efficient transport and separation of carriers and boosted production of superoxide radicals (·O2-) through the combination of a wide-bandgap ornament BiPO4 as an electron acceptor. In particular, the composite PB5 with the optimal phase composition exhibited the highest NOx removal of 40% with the lowest NO2 formation of 40 ppb among all tested candidates. According to the band structures' estimation and reactive species' detection, a reasonable mechanism was ultimately proposed to describe the migration of charge carriers and the enhancement of photocatalytic performance.


Assuntos
Luz , Oxidantes , Superóxidos
12.
J Virol ; 94(22)2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32878885

RESUMO

Innate immunity is an essential way for host cells to resist viral infection through the production of interferons (IFNs) and proinflammatory cytokines. Interferon regulatory factor 3 (IRF3) plays a critical role in the innate immune response to viral infection. However, the role of IRF1 in innate immunity remains largely unknown. In this study, we found that IRF1 is upregulated through the IFN/JAK/STAT signaling pathway upon viral infection. The silencing of IRF1 attenuates the innate immune response to viral infection. IRF1 interacts with IRF3 and augments the activation of IRF3 by blocking the interaction between IRF3 and protein phosphatase 2A (PP2A). The DNA binding domain (DBD) of IRF1 is the key functional domain for its interaction with IRF3. Overall, our study reveals a novel mechanism by which IRF1 promotes the innate immune response to viral infection by enhancing the activation of IRF3, thereby inhibiting viral infection.IMPORTANCE The activation of innate immunity is essential for host cells to restrict the spread of invading viruses and other pathogens. IRF3 plays a critical role in the innate immune response to RNA viral infection. However, whether IRF1 plays a role in innate immunity is unclear. In this study, we demonstrated that IRF1 promotes the innate immune response to viral infection. IRF1 is induced by viral infection. Notably, IRF1 targets and augments the phosphorylation of IRF3 by blocking the interaction between IRF3 and PP2A, leading to the upregulation of innate immunity. Collectively, the results of our study provide new insight into the regulatory mechanism of IFN signaling and uncover the role of IRF1 in the positive regulation of the innate immune response to viral infection.


Assuntos
Imunidade Inata/imunologia , Fator Regulador 1 de Interferon/imunologia , Fator Regulador 3 de Interferon/metabolismo , Viroses/imunologia , Linhagem Celular , Proteínas de Ligação a DNA , Células HEK293 , Humanos , Fator Regulador 1 de Interferon/metabolismo , Fosforilação , Infecções por Vírus de RNA/imunologia , Vírus de RNA , Transdução de Sinais/imunologia
13.
J Virol ; 93(14)2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31068419

RESUMO

The Src-associated in mitosis 68-kDa (Sam68) protein is a highly conserved nuclear protein and is involved in a series of cellular processes, including transcription and signal transduction. Sam68 is comprised of 443 amino acids and contains an RGG box domain, a KH domain, and a tyrosine-rich domain. Its role in hepatitis C virus (HCV) replication is unknown. Here, we find that Sam68 promotes HCV replication without affecting viral translation. The RNA immunoprecipitation experiments show that the positive strand of HCV RNA interacts with Sam68. HCV infection triggers the translocation of the Sam68 protein from the nucleus to the cytoplasm, where it interacts with the HCV genome. Further study shows that the region of Sam68 spanning amino acids 1 to 157 is the pivotal domain to interact with the stem-loop 2 of the HCV 5' untranslated region (5' UTR) and is responsible for the enhancement of HCV replication. These data suggested that Sam68 may serve as a proviral factor of HCV to facilitate viral replication through interaction with the viral genome.IMPORTANCE Hepatitis C virus (HCV) is a member of the Flaviviridae family, and its infection causes chronic hepatitis, liver cirrhosis, and even hepatocellular carcinoma. No vaccine is available. Many host factors may be implicated in the pathogenesis of HCV-related diseases. This study discloses a new host factor that binds to the HCV 5' UTR and promotes HCV replication. Sam68 may play an important role in HCV-related diseases, and further investigation is highly encouraged to explore its specific actions in HCV pathogenesis.


Assuntos
Regiões 5' não Traduzidas , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Hepacivirus/fisiologia , Conformação de Ácido Nucleico , RNA Viral/metabolismo , Proteínas de Ligação a RNA/metabolismo , Replicação Viral/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Genoma Viral , Hepatite C/genética , Hepatite C/metabolismo , Hepatite C/patologia , Humanos , RNA Viral/genética , Proteínas de Ligação a RNA/genética
14.
J Virol ; 92(17)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29899107

RESUMO

Emerging evidence indicates that long noncoding RNAs (lncRNAs) regulate various biological processes, especially innate and adaptive immunity. However, the relationship between lncRNAs and the interferon (IFN) pathway remains largely unknown. Here, we report that lncRNA ITPRIP-1 (lncITPRIP-1) is involved in viral infection and plays a crucial role in the virus-triggered IFN signaling pathway through the targeting of melanoma differentiation-associated gene 5 (MDA5). LncITPRIP-1 can be induced by viral infection, which is not entirely dependent on the IFN signal. Besides, there is no coding potential found in the lncITPRIP-1 transcript. LncITPRIP-1 binds to the C terminus of MDA5, and it possesses the ability to boost the oligomerization of both the full length and the 2 caspase activation and recruitment domains of MDA5 in a K63-linked polyubiquitination-independent manner. Amazingly, we also found that MDA5 can suppress hepatitis C virus (HCV) replication independently of IFN signaling through its C-terminal-deficient domain bound to viral RNA, in which lncITPRIP-1 plays a role as an assistant. In addition, the expression of lncITPRIP-1 is highly consistent with MDA5 expression, indicating that lncITPRIP-1 may function as a cofactor of MDA5. All the data suggest that lncITPRIP-1 enhances the innate immune response to viral infection through the promotion of oligomerization and activation of MDA5. Our study discovers the first lncRNA ITPRIP-1 involved in MDA5 activation.IMPORTANCE Hepatitis C virus infection is a global health issue, and there is still no available vaccine, which makes it urgent to reveal the underlying mechanisms of HCV and host factors. Although RIG-I has been recognized as the leading cytoplasmic sensor against HCV for a long time, recent findings that MDA5 regulates the IFN response to HCV have emerged. Our work validates the significant role of MDA5 in IFN signaling and HCV infection and proposes the first lncRNA inhibiting HCV replication by promoting the activation of MDA5 and mediating the association between MDA5 and HCV RNA, the study of which may shed light on the MDA5 function and treatment for hepatitis C patients. Our suggested model of how lncITPRIP-1 orchestrates signal transduction for IFN production illustrates the essential role of lncRNAs in virus elimination.


Assuntos
Imunidade Inata/fisiologia , Helicase IFIH1 Induzida por Interferon/genética , Interferons/imunologia , Proteínas de Membrana/fisiologia , RNA Longo não Codificante/fisiologia , Transdução de Sinais/imunologia , Linhagem Celular , Regulação da Expressão Gênica/imunologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/imunologia , Helicase IFIH1 Induzida por Interferon/fisiologia , Interferons/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , RNA Viral/genética , Transdução de Sinais/genética
15.
J Environ Sci (China) ; 76: 188-198, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30528009

RESUMO

Phosphate residue is regarded as a hazardous waste, which could potentially create significant environmental and health problems if it is not properly treated and disposed of. In this study, nitrogen-doped carbon nanotubes-FePO4 (NCNTs-FePO4) composite was successfully synthesized from phosphate residue, and its application as an effective catalyst was explored. Firstly, an effective method was developed to recover FePO4 from phosphate residue, achieving an impressive FePO4 mass recovery rate of 98.14%. Then, the NCNTs-FePO4 catalyst was synthesized from the recovered FePO4 by two main reactions, including surface modification and chemical vapor deposition. Finally, the synthesized NCNTs-FePO4 was applied to photo-degrade 15 mg/L Rhodamine B (RhB) in a Fenton-like system. The results showed that 98.9% of RhB could be degraded in 60 min, closely following the pseudo-first-order kinetics model. It was found that even after six consecutive cycles, NCNTs-FePO4 still retained a high catalytic capacity (>50%). Moreover, •OH radicals participating in the RhB degradation process were evidenced using quenching experiments and electron paramagnetic resonance analysis, and a rational mechanism was proposed. It was demonstrated that the materials synthesized from hazardous phosphate residue can be used as an effective catalyst for dye removal.


Assuntos
Corantes/química , Compostos Férricos/química , Nanotecnologia , Nanotubos de Carbono/química , Nitrogênio/química , Fosfatos/química , Poluentes Químicos da Água/química , Catálise , Técnicas de Química Sintética , Corantes/isolamento & purificação , Peróxido de Hidrogênio/química , Ferro/química , Nanocompostos/química , Rodaminas/química , Rodaminas/isolamento & purificação , Água/química , Poluentes Químicos da Água/isolamento & purificação
16.
J Virol ; 90(15): 6832-45, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27194766

RESUMO

UNLABELLED: Interferons (IFNs) restrict various kinds of viral infection via induction of hundreds of IFN-stimulated genes (ISGs), while the functions of the majority of ISGs are broadly unclear. Here, we show that a high-IFN-inducible gene, ISG12a (also known as IFI27), exhibits a nonapoptotic antiviral effect on hepatitis C virus (HCV) infection. Viral NS5A protein is targeted specifically by ISG12a, which mediates NS5A degradation via a ubiquitination-dependent proteasomal pathway. K374R mutation in NS5A domain III abrogates ISG12a-induced ubiquitination and degradation of NS5A. S-phase kinase-associated protein 2 (SKP2) is identified as an ubiquitin E3 ligase for NS5A. ISG12a functions as a crucial adaptor that promotes SKP2 to interact with and degrade viral protein. Moreover, the antiviral effect of ISG12a is dependent on the E3 ligase activity of SKP2. These findings uncover an intriguing mechanism by which ISG12a restricts viral infection and provide clues for understanding the actions of innate immunity. IMPORTANCE: Upon virus invasion, IFNs induce numerous ISGs to control viral spread, while the functions of the majority of ISGs are broadly unclear. The present study shows a novel antiviral mechanism of ISGs and elucidated that ISG12a recruits an E3 ligase, SKP2, for ubiquitination and degradation of viral protein and restricts viral infection. These findings provide important insights into exploring the working principles of innate immunity.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C/prevenção & controle , Proteínas de Membrana/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ubiquitina/metabolismo , Proteínas não Estruturais Virais/metabolismo , Células Cultivadas , Hepatite C/metabolismo , Hepatite C/virologia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Humanos , Proteólise , Ubiquitinação
17.
Environ Sci Technol ; 49(17): 10589-97, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26218836

RESUMO

Nano zerovalent iron synthesized with carboxymethylcelluose (CMC-nZVI) is among the leading formulations of nZVI currently used for in situ groundwater remediation. The main advantage of CMC-nZVI is that it forms stable suspensions, which are relatively mobile in porous media. Rapid contaminant reduction by CMC-nZVI is well documented, but the fate of the CMC-nZVI (including "aging" and "reductant demand") is not well characterized. Improved understanding of CMC-nZVI fate requires methods with greater specificity for Fe(0), less vulnerability to sampling/recovery artifacts, and more practical application in the field. These criteria can be met with a simple and specific colorimetric approach using indigo-5,5'-disulfonate (I2S) as a chemical redox probe (CRP). The measured stoichiometric ratio for reaction between I2S and nZVI is 1.45 ± 0.03, suggesting complete oxidation of nZVI to Fe(III) species. However, near pH 7, reduction of I2S is diagnostic for Fe(0), because aqueous Fe(II) reduces I2S much more slowly than Fe(0). At that pH, adding Fe(II) increased I2S reduction rates by Fe(0), consistent with depassivation of nZVI, but did not affect the stoichiometry. Using the I2S assay to quantify changes in the Fe(0) content of CMC-nZVI, the rate of Fe(0) oxidation by water was found to be orders of magnitude faster than previously reported values for other types of nZVI.


Assuntos
Carboximetilcelulose Sódica/química , Ferro/química , Nanopartículas/química , Elétrons , Água Subterrânea/química , Cinética , Sondas Moleculares/química , Oxirredução , Porosidade , Água/química
18.
Antiviral Res ; 222: 105797, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38185222

RESUMO

RNA viral infections seriously endanger human health. Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 2 (SHP2) suppresses innate immunity against influenza A virus, and pharmacological inhibition of SHP2 provokes hepatic innate immunity. SHP2 binds and catalyzes tyrosyl dephosphorylation of protein zero-related (PZR), but the regulatory effect of PZR on innate immune response to viral infection is unclear. In this study, the transcription and protein level of PZR in host cells were found to be decreased with RNA viral infection, and high level of PZR was uncovered to inhibit interferon (IFN) signaling mediated by RIG-I and MDA5. Through localizing in mitochondria, PZR targeted and interacted with MAVS (also known as IPS-1/VISA/Cardif), suppressing the aggregation and activation of MAVS. Specifically, Y263 residue in ITIM is critical for PZR to exert immunosuppression under RNA viral infection. Moreover, the recruited SHP2 by PZR that modified with tyrosine phosphorylation under RNA viral infection might inhibit phosphorylation activation of MAVS. In conclusion, PZR and SHP2 suppress innate immune response to RNA viral infection through inhibiting MAVS activation. This study reveals the regulatory mechanism of PZR-SHP2-MAVS signal axis on IFN signaling mediated by RIG-I and MDA5, which may provide new sight for developing antiviral drugs.


Assuntos
Infecções por Vírus de RNA , Vírus de RNA , Viroses , Humanos , Transdução de Sinais , Proteína DEAD-box 58 , Imunidade Inata , Interferons , RNA
19.
Wei Sheng Yan Jiu ; 42(1): 67-71, 2013 Jan.
Artigo em Zh | MEDLINE | ID: mdl-23596710

RESUMO

OBJECTIVE: To analyze the status of malnutrition and its influencing factors in children under 5 years old in Guangnan District of Yunnan Province in 2009 - 2010. METHODS: By the random cluster sampling and stratified sampling methods, 1002 children within 5 years old in rural areas were selected from poverty-stricken counties in Yunnan Province. The questionnaire survey including questionnaire, anthropometric measurement and dietary survey such as height and weight were used respectively for the survey. Z score was used for evaluating the nutritional status. The prevalence of malnutrition was calculated by statistics software. Multiple factors analysis was finished by non condition Logistic regression in software. RESULTS: During 2009 - 2010, of all children under the age of 5 years old, the underweight rate is 18.8%, stunted growth rate is 34.3% and emaciation rate is 3.1% in impoverished rural area of Yunnan Province. Removing other variables, the result indicated: (1) Comparing with these children under 2 years old who are provided with breastfeeding, the children under 2 years old who are not given breastfeeding are more possible to get malnutrition. (2) The children under 2 years old who were added more vegetable and fruit supplement are less possible to get malnutrition than those children who were added less vegetable and fruit supplement during the past 7 days. (3) The children under 2 years old with good conditions are less possible to get malnutrition than the children with normal conditions or bad conditions. CONCLUSION: Malnutrition in children under 5 years old in pour rural areas of Yunnan province should not be ignored. The main influencing factors of children malnutrition include feeding ways, increasing supplementary food, and the conditions compared with other children under 2 years old.


Assuntos
Desnutrição/epidemiologia , População Rural , Pré-Escolar , China/epidemiologia , Inquéritos sobre Dietas , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Áreas de Pobreza , Prevalência , Estudos de Amostragem , Inquéritos e Questionários , Magreza/epidemiologia
20.
Environ Sci Pollut Res Int ; 30(6): 14240-14252, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36149563

RESUMO

Sulfidated nanoscale zerovalent iron (S-nZVI) supported on a flower spherical Mg(OH)2 with different Mg/Fe ration were successfully synthesized. The synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS). The results showed that S-nZVI particles were well dispersed on the petals of the flower spherical Mg(OH)2. The influence of factors, including the initial solution pH, Mg/Fe, S/Fe were studied. The trichloroethylene (TCE) adsorption data on Mg(OH)2 and S-nZVI @Mg(OH)2 fit well to a Langmuir isotherm model, and the maximum adsorption of S-nZVI @Mg(OH)2 was 253.55 mg/g, which was 2.6-fold of S-nZVI. Meanwhile, the S-nZVI @Mg(OH)2 composite expanded the pH selection range of S-nZVI from 2 to 11. Cycling experiments showed that removal rate was 58.3% for the 5th cycle. TCE removal was due to synergistic action of reduction coupled with adsorption. During this process, 65.43% of total remove TCE from ion chromatography data was reduced and 34.57% of total remove TCE was adsorbed finally. At the same time, adsorption favors reduction. These observations indicated that the S-nZVI @Mg(OH)2 can be considered as potential adsorbents to remove TCE for environment remediation.


Assuntos
Recuperação e Remediação Ambiental , Tricloroetileno , Poluentes Químicos da Água , Tricloroetileno/química , Ferro/química , Adsorção , Difração de Raios X , Poluentes Químicos da Água/química
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa