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Developing a highly efficient atom-economic method for the preparation of 3-(1-heteroarylethyl)-indole scaffolds is of significant value in pharmaceutical and agricultural chemistry. Herein, a phosphoric acid-catalyzed N-addition reaction of 3-vinyl indoles with pyrazoles and C-addition reaction of 3-vinyl indoles with pyrazolones were developed. A series of pyrazole-substituted 3-(1-heteroarylethyl)-indole scaffolds were synthesized in excellent yields (up to 99% yield) under mild reaction conditions. A reasonable reaction mechanism was proposed to explain the experimental results.
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New synthetic methods to construct 2,2-disubstituted tetrahydroquinoline derivatives are of significant value in pharmaceutical chemistry. Herein, a Rh(II)/Pd(0) dual-catalyzed diazo α-aminoallylation reaction has been developed between allylpalladium(II) and ammonium ylides derived from the Rh2(OAc)4-mediated intramolecular N-H bond insertion reaction of diazo compounds, affording various 2,2-disubstituted tetrahydroquinoline derivatives in good yields up to 93% with high chemoselectivities under mild reaction conditions. A substrate scope investigation reveals broad ester substituent tolerance, and control experiments provide the basis for a proposed reaction mechanism.
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Compostos de Amônio , Compostos de Amônio/química , Paládio/química , Estereoisomerismo , CatáliseRESUMO
NF-κB plays a crucial role in regulating cell proliferation, inflammation, apoptosis, and immune responses. HSV type 2 (HSV-2) is one of the most predominant sexually transmitted pathogens worldwide, and its infection increases the risk of HIV type 1 (HIV-1) acquisition and transmission. HSV-2 glycoprotein D (gD), highly homologous to HSV-1 gD, is essential for viral adhesion, fusion, entry, and spread. It is known that HSV-1 gD can bind herpesvirus entry mediator (HVEM) to trigger NF-κB activation and thereby facilitate viral replication at the early stage of infection. In this study, we found that purified HSV-2 gD triggered NF-κB activation at the early stage of infection, whereas ectopic expression of HSV-2 gD significantly downregulated TNF-α-induced NF-κB activity as well as TNF-α-induced IL-6 and IL-8 expression. Mechanistically, HSV-2 gD inhibited NF-κB, but not IFN-regulatory factor 3 (IRF3), activation and suppressed NF-κB activation mediated by overexpression of TNFR-associated factor 2 (TRAF2), IκB kinase α (IKKα), IKKß, or p65. Coimmunoprecipitation and binding kinetic analyses demonstrated that HSV-2 gD directly bound to the NF-κB subunit p65 and abolished the nuclear translocation of p65 upon TNF-α stimulation. Mutational analyses further revealed that HSV-2 gD interacted with the region spanning aa 19-187 of p65. Findings in this study together demonstrate that HSV-2 gD interacts with p65 to regulate p65 subcellular localization and thereby prevents NF-κB-dependent gene expression, which may contribute to HSV-2 immune evasion and pathogenesis.
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Herpesvirus Humano 2/imunologia , Fator de Transcrição RelA/imunologia , Proteínas do Envelope Viral/imunologia , Células HEK293 , Células HeLa , HumanosRESUMO
An efficient Pd-catalyzed direct C-H arylation of pyrrolo[1,2-a]quinoxalines with aryl iodides is described, providing a selective route toward a series of 1-arylated and 1,3-diarylated pyrrolo[1,2-a]quinoxalines in good yields. This method features a broad substrate scope, good functional group tolerance and gram-scale synthesis. Furthermore, the C3-thiocyanation of the arylated product is also achieved. We believe that these novel aryl-substituted pyrrolo [1,2-a]quinoxalines will have a variety of applications in organic synthesis and medicinal chemistry.
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Middle aortic syndrome (MAS) is a rare disease characterized by distal thoracic aorta or abdominal aorta coarctation, and thoraco-abdominal aortic bypass grafting is an effective treatment for this condition. However, significant trauma is associated with the conventional surgical approach. We report a 26-year-old woman with MAS who presented with hypertension and needed thoraco-abdominal bypass grafting. In this operation, we adopted the endoscopic technique to improve the conventional surgical approach (reduce the incision). This case report shows that it is safe and feasible to use an endoscopic technique to reduce the trauma during this kind of operation, and provides a reference for similar treatments.
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Coartação Aórtica , Doenças da Aorta , Adulto , Aorta , Aorta Abdominal/cirurgia , Aorta Torácica/cirurgia , Coartação Aórtica/complicações , Coartação Aórtica/cirurgia , Endoscópios , Feminino , HumanosRESUMO
The role of retinoic acid-inducible gene I (RIG-I) in foot-and-mouth disease virus (FMDV)-infected cells remains unknown. Here, we showed that RIG-I inhibits FMDV replication in host cells. FMDV infection increased the transcription of RIG-I, while it decreased RIG-I protein expression. A detailed analysis revealed that FMDV leader proteinase (Lpro), as well as 3C proteinase (3Cpro) and 2B protein, decreased RIG-I protein expression. Lpro and 3Cpro are viral proteinases that can cleave various host proteins and are responsible for several of the viral polyprotein cleavages. However, for the first time, we observed 2B-induced reduction of host protein. Further studies showed that 2B-mediated reduction of RIG-I is specific to FMDV, but not other picornaviruses, including encephalomyocarditis virus, enterovirus 71, and coxsackievirus A16. Moreover, we found the decreased protein level of RIG-I is independent of the cleavage of eukaryotic translation initiation factor 4 gamma, the induction of cellular apoptosis, or the association of proteasome, lysosome, and caspase pathways. A direct interaction was observed between RIG-I and 2B. The carboxyl-terminal amino acids 105 to 114 and amino acids 135 to 144 of 2B were essential for the reduction of RIG-I, while residues 105 to 114 were required for the interaction. These data suggest the antiviral role of RIG-I against FMDV and a novel antagonistic mechanism of FMDV that is mediated by 2B protein. IMPORTANCE: This study demonstrated that RIG-I could suppress FMDV replication during virus infection. FMDV infection increased the transcriptional expression of RIG-I, while it decreased RIG-I protein expression. FMDV 2B protein interacted with RIG-I and induced reduction of RIG-I. 2B-induced reduction of RIG-I was independent of the induction of the cleavage of eukaryotic translation initiation factor 4 gamma or cellular apoptosis. In addition, proteasome, lysosome, and caspase pathways were not involved in this process. This study provides new insight into the immune evasion mediated by FMDV and identifies 2B as an antagonistic factor for FMDV to evade the antiviral response.
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Cisteína Endopeptidases/genética , Proteína DEAD-box 58/genética , Endopeptidases/genética , Fator de Iniciação Eucariótico 4G/genética , Vírus da Febre Aftosa/genética , Interações Hospedeiro-Patógeno , Proteínas Virais/genética , Proteínas Virais Reguladoras e Acessórias/genética , Proteases Virais 3C , Sequência de Aminoácidos , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Cricetulus , Cisteína Endopeptidases/imunologia , Proteína DEAD-box 58/imunologia , Vírus da Encefalomiocardite/genética , Vírus da Encefalomiocardite/imunologia , Endopeptidases/imunologia , Enterovirus/genética , Enterovirus/imunologia , Enterovirus Suínos/genética , Enterovirus Suínos/imunologia , Células Epiteliais , Fator de Iniciação Eucariótico 4G/imunologia , Vírus da Febre Aftosa/imunologia , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Ligação Proteica , Transdução de Sinais , Especificidade da Espécie , Suínos , Proteínas Virais/imunologia , Proteínas Virais Reguladoras e Acessórias/imunologiaRESUMO
Diastereoselective aldol reaction of N-tert-butanesulfinyl imidates under typical hard enolization conditions is reported. Potassium bis(trimethylsilyl)amide (KHMDS) effectively promotes the aldol reaction of α-aryl- and α-alkyl-substituted imidates, providing anti-aldol adducts in high yields with good to excellent diastereoselectivities. In the case of α-aryl imidates, high conversion depends on adding trimethylsilyl chloride (TMSCl) to the reaction mixture. In the presence of a suitable Lewis acid, cyclohexanone is a good electrophile in the aldol reaction of imidates.
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Lung cancer is the first leading cause of cancer deaths. Chemotherapy toxicity is one of factors that limited the efficacy of platinum-based chemotherapy in lung cancer patients. Transporters and DNA repair genes play critical roles in occurrence of platinum-based chemotherapy toxicity. To investigate the relationships between transporter and DNA repair gene polymorphisms and platinum-based chemotherapy toxicity in lung cancer patients, we selected 60 polymorphisms in 14 transporters and DNA repair genes. The polymorphisms were genotyped in 317 lung cancer patients by Sequenom MassARRAY. Logistic regression was performed to estimate the association of toxicity outcome with the polymorphisms by PLINK. Our results showed that polymorphisms of SLC2A1 (rs3738514, rs4658, rs841844) were significantly related to overall toxicity. XRCC5 (rs1051685, rs6941) and AQP2 (10875989, rs3759125) polymorphisms were associated with hematologic toxicity. AQP2 polymorphisms (rs461872, rs7305534) were correlated with gastrointestinal toxicity. In conclusion, genotypes of these genes may be used to predict the platinum-based chemotherapy toxicity in lung cancer patients.
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Aquaporina 2/genética , Transportador de Glucose Tipo 1/genética , Autoantígeno Ku/genética , Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Antineoplásicos/efeitos adversos , Reparo do DNA/genética , Feminino , Genótipo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Mesenchymal stem cell therapy is a new treatment for immune rejection in heart transplantation. The aim of this paper is to investigate the effect of human amniotic mesenchymal stem cells (hAMSCs) on alleviating immune rejection of allogeneic heart transplantation in mice and its possible underlying mechanism. METHODS: We injected hAMSCs into cervical ectopic heart transplantation model mice via tail vein to observe the survival time, the pathological changes of donor myocardium, and the fluorescent distribution of hAMSCs after the transplantation. MicroRNAs (miRs) with significantly differential expression were obtained by RNA sequencing and bioinformatic analysis, and a dual luciferase reporter gene assay together with real-time quantitative PCR (qRT-PCR) was performed to verify the relationship between miRs and their targeting genes. RESULTS: The intervention of hAMSCs prolonged the graft survival time and alleviated the pathological damage of the donor heart. The injected hAMSCs were distributed mainly in the liver, spleen, and kidney, only a very small portion in the donor and recipient hearts. In the allogeneic transplantation models, the expression of miR-34b-5p significantly increased after hAMSC treatment. MiR-34b-5p showed a knockdown effect on gene Fc gamma receptor 2B (FCGR2B). CONCLUSIONS: hAMSCs can reduce the immune rejection injury after allogeneic heart transplantation. This effect may be associated with the upregulation of miR-34b-5p expression to knock down its targeting gene FCGR2B.
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Âmnio , Rejeição de Enxerto , Transplante de Coração , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , MicroRNAs , Transplante Homólogo , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Camundongos , Rejeição de Enxerto/imunologia , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/imunologia , Âmnio/citologia , Camundongos Endogâmicos BALB C , Células Cultivadas , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Sobrevivência de Enxerto/imunologia , Feminino , MasculinoRESUMO
Thiopental sodium (TPTS) is a barbiturate general anesthetic, while its effects on hypoxia/reoxygenation (H/R)-induced injury are still unclear. This study aimed to investigate whether TPTS exerts protective effects against the H/R-induced osteoblast cell injury and explore the underlying mechanisms. Osteoblast cell injury model was induced by the H/R condition, which was treated with or without TPTS. Cell viability and lactate dehydrogenase (LDH) release were determined by the corresponding commercial kits. The levels of oxidative stress were determined in the experimental groups. Cell apoptosis and Caspase-3 activities were determined by propidium iodide staining and substrate-based assay, respectively. Western blotting and qRT-PCR were performed to measure the mRNA and protein levels, respectively. Treatment with TPTS was able to increase cell viability and reduce LDH release in H/R-induced osteoblasts. Additionally, TPTS regulated oxidative stress in H/R-induced osteoblasts by suppressing malondialdehyde (MDA) and reactive oxygen species (ROS) as well as boosting superoxide dismutase (SOD). TPTS was able to suppress cell apoptosis by suppressing Caspase-3 activity and cleavage. TPTS exerted protective effects against cell injury and apoptosis induced by the H/R conditions, which were associated with its regulation of Akt signaling. Moreover, TPTS induced osteoblast differentiation under the H/R condition. In summary, TPTS attenuates H/R-induced injury in osteoblasts by regulating AKT signaling.
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Proteínas Proto-Oncogênicas c-akt , Tiopental , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tiopental/farmacologia , Tiopental/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Hipóxia/metabolismo , Estresse Oxidativo , Apoptose , Hipóxia Celular , Miócitos Cardíacos/metabolismo , Sobrevivência CelularRESUMO
Chronic constrictive pericarditis (CCP) is one of the common causes of cardiogenic cirrhosis; it is rare for a patient to have both CCP and recurrent black stool, so we consider that CCP causes cardiogenic cirrhosis. Cardiogenic cirrhosis caused portal hypertension which then resulted in gastrointestinal bleeding. Herein, we report a case of a 40-year-old Chinese woman suffering from CCP who had upper gastrointestinal bleed and had to undergo emergency surgery. Two years after the emergency surgery, multiple reexaminations showed significantly improved cardiac functions, hemoglobin, and WBC levels and gastrointestinal functions.
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Pericardite Constritiva , Adulto , Feminino , Seguimentos , Hemorragia Gastrointestinal/complicações , Humanos , Cirrose Hepática/complicações , Pericardiectomia/efeitos adversos , Pericardiectomia/métodos , Pericardite Constritiva/complicações , Pericardite Constritiva/cirurgiaRESUMO
Herpes simplex virus type 2 (HSV-2) is a prevalent human pathogen and the main cause of genital herpes. After initial infection, HSV-2 can establish lifelong latency within dorsal root ganglia by evading the innate immunity of the host. NF-κB has a crucial role in regulating cell proliferation, inflammation, apoptosis, and immune responses. It is known that inhibition of NF-κB activation by a virus could facilitate it to establish infection in the host. In the current study, we found that HSV-2 inhibited TNF-α-induced activation of NF-κB-responsive promoter in a dose-dependent manner, while UV-inactivated HSV-2 did not have such capability. We further identified the immediate early protein ICP22 of HSV-2 as a vital viral element in inhibiting the activation of NF-κB-responsive promoter. The role of ICP22 was confirmed in human cervical cell line HeLa and primary cervical fibroblasts in the context of HSV-2 infection, showing that ICP22 deficient HSV-2 largely lost the capability in suppressing NF-κB activation. HSV-2 ICP22 was further shown to suppress the activity of TNF receptor-associated factor 2 (TRAF2)-, IκB kinase α (IKK α)-, IKK ß-, IKK γ-, or p65-induced activation of NF-κB-responsive promoter. Mechanistically, HSV-2 ICP22 inhibited the phosphorylation and nuclear translocation of p65 by directly interacting with p65, resulting in the blockade of NF-κB activation. Furthermore, ICP22 from several alpha-herpesviruses could also inhibit NF-κB activation, suggesting the significance of ICP22 in herpesvirus immune evasion. Findings in this study highlight the importance of ICP22 in inhibiting NF-κB activation, revealing a novel mechanism by which HSV-2 evades the host antiviral responses.
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Herpesvirus Humano 1 , Proteínas Imediatamente Precoces , Antivirais , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 2/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , NF-kappa B/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Virais/metabolismoRESUMO
BACKGROUND: Immune rejection of heart transplantation has been regarded as the biggest challenge encountered by a patient suffering from end-stage heart disease. The transplantation of human amnion-derived mesenchymal stem cells (hAD-MSCs) has exhibited promising application prospects in organ transplantation. However, its persistent unsatisfactory tolerance has limited the widespread application of this technology. We aim to investigate the role of tumor necrosis factor-α-induced protein-8 like-2 (TIPE2)-mediated hAD-MSCs in immune tolerance in heart transplantation and its molecular regulatory mechanisms. METHODS: This project detected the effect of TIPE2 on immune tolerance by constructing an allogeneic heart transplantation mouse model through which TIPE2-overexpressed hAD-MSCs were injected into recipients. The fluorescence distribution of TIPE2-hAD-MSCs in mice was observed by a small animal in vivo imaging system. Pathological changes of the transplanted heart were detected by hematoxylin and eosin (HE) staining. Flow cytometry was performed to detect the content of cardiac lymphocytes. The expression of immune-induced related factors was measured by quantitative real-time PCR (qRT-PCR) and western blot assays. RESULTS: TIPE2-hAD-MSCs protected myocardial tissue structures, reduced the spleen and thymus indexes in recipient mice, minimized the content of cardiac lymphocytes, reduced expressions of ERK, p38, and IFN-γ, and elevated expressions of both IL-10 and TGF-ß, markedly improving the survival time and survival rates of recipient mice. CONCLUSIONS: TIPE2-hAD-MSCs induce immune tolerance and improve the survival rates of allogeneic heart transplantation in mice. This study is expected to offer an ideal source and target of cells for organ transplantation.
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Zika virus (ZIKV) infections can cause microcephaly and neurological disorders. However, the early infection events of ZIKV in neural cells remain to be characterized. Here, by using a combination of pharmacological and molecular approaches and the human glioblastoma cell T98G as a model, we first observed that ZIKV infection was inhibited by chloroquine and NH4Cl, indicating a requirement of low intracellular pH. We further showed that dynamin is required as the ZIKV entry was affected by the specific inhibitor dynasore, small interfering RNA (siRNA) knockdown of dynamin, or by expressing the dominant-negative K44A mutant. Moreover, the ZIKV entry was significantly inhibited by chlorpromazine, pitstop2, or siRNA knockdown of clathrin heavy chain, indicating an involvement of clathrin-mediated endocytosis. In addition, genistein treatment, siRNA knockdown of caveolin-1, or overexpression of a dominant-negative caveolin mutant impacted the ZIKV entry, with ZIKV particles being observed to colocalize with caveolin-1, implying that caveola endocytosis can also be involved. Furthermore, we found that the endocytosis of ZIKV is dependent on membrane cholesterol, microtubules, and actin cytoskeleton. Importantly, ZIKV infection was inhibited by silencing of Rab5 and Rab7, while confocal microscopy showed that ZIKV particles localized in Rab5- and Rab7-postive endosomes. These results indicated that, after internalization, ZIKV likely moves to Rab5-positive early endosome and Rab7-positive late endosomes before delivering its RNA into the cytoplasm. Taken together, our study, for the first time, described the early infection events of ZIKV in human glioblastoma cell T98G.
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Treating chiral N-tert-butanesulfinyl ketimines with potassium hexamethyldisilazide (or potassium tert-butoxide) and methyl triflate gives N-methylated N-tert-butanesulfinyl enamine intermediates that undergo stereoselective [2,3]-rearrangement to afford α-sulfenyloxy ketones with excellent enantiopurities. This cascade of enamination-N-methylation-rearrangement was even used to generate acyclic tertiary α-hydroxy ketones bearing two α-substituents showing negligible differences in bulkiness, such as methyl and ethyl groups.
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HSV-2 spread is predominantly dependent on cell-to-cell contact. However, the underlying mechanisms remain to be determined. Here we demonstrate that HSV-2 gJ, which was previously assigned no specific function, promotes HSV-2 cell-to-cell spread and syncytia formation. In the context of viral infection, knockout or knockdown of gJ impairs HSV-2 cell-to-cell spread among epithelial cells or from epithelial cells to neuronal cells, which leads to decreased virus production, whereas ectopic expression of gJ enhances virus production. Mechanistically, gJ increases the expression levels of HSV-2 proteins, and also enhances viral protein expression and replication of heterologous viruses like HIV-1 and JEV, suggesting that HSV-2 gJ likely functions as a regulator of viral protein expression and virus production. Findings in this study provide a basis for further understanding the role of gJ in HSV-2 replication.
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Células Epiteliais/virologia , Regulação Viral da Expressão Gênica/fisiologia , Herpesvirus Humano 2/fisiologia , Neurônios/virologia , Proteínas do Envelope Viral/metabolismo , Linhagem Celular , Proteínas do Envelope Viral/genética , Fenômenos Fisiológicos Virais , Replicação ViralRESUMO
The interferon-induced double-strand RNA activated protein kinase (PKR) plays important roles in host defense against viral infection. Here we demonstrate the significant antiviral role of PKR against foot-and-mouth disease virus (FMDV) and report that FMDV infection inhibits PKR expression and activation in porcine kidney (PK-15) cells. The viral nonstructural protein 3C proteinase (3Cpro) is identified to be responsible for this inhibition. However, it is independent of the well-known proteinase activity of 3Cpro or 3Cpro-induced shutoff of host protein synthesis. We show that 3Cpro induces PKR degradation by lysosomal pathway and no interaction is determined between 3Cpro and PKR. Together, our results indicate that PKR acts an important antiviral factor during FMDV infection, and FMDV has evolved a strategy to overcome PKR-mediated antiviral role by downregulation of PKR protein.
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Cisteína Endopeptidases/metabolismo , Vírus da Febre Aftosa/patogenicidade , Interações Hospedeiro-Patógeno , Lisossomos/metabolismo , Proteólise , Proteínas Virais/metabolismo , Replicação Viral , eIF-2 Quinase/antagonistas & inibidores , Proteases Virais 3C , Animais , Linhagem Celular , Vírus da Febre Aftosa/enzimologia , SuínosRESUMO
The role of the innate immune protein LGP2 (laboratory of genetics and physiology 2) in FMDV-infected cells remains unknown. Here, we demonstrate the antiviral role of LGP2 during FMDV infection. FMDV infection triggered LGP2 mRNA expression but reduced protein expression. Overexpression of LGP2 suppressed FMDV replication, and the inflammatory response was significantly inhibited by LGP2 in virus-infected cells. The N-terminal DExDc and the C-terminal regulatory domain regions of LGP2 were essential for LGP2-mediated antiviral activity against FMDV. Disruption of RNA recognition by LGP2 is suggested to abolish completely LGP2-mediated antiviral activity against FMDV. FMDV leader protein (Lpro), as well as the 3Cpro and 2B proteins were determined to possess the ability to induce reduction of LGP2 protein expression. 2B-induced reduction of LGP2 was independent of cleavage of eukaryotic translation initiation factor 4 gamma; and the proteasomes, lysosomes or caspase-dependent pathways were not involved in this process. The C-terminal amino acids of 101-154 were essential for 2B-induced reduction of LGP2 and upregulation of inflammatory response. Direct interaction was demonstrated between LGP2 and 2B. Our results describe the antiviral role of LGP2 against FMDV and a novel antagonistic mechanism of FMDV that is mediated by 2B protein.