RESUMEN
The tripartite motif (TRIM) protein family is the largest subfamily of E3 ubiquitin ligases, playing a crucial role in the antiviral process. In this study, we found that TRIM72, a member of the TRIM protein family, was increased in neuronal cells and mouse brains following rabies lyssavirus (RABV) infection. Over-expression of TRIM72 significantly reduced the viral titer of RABV in neuronal cells and mitigated the pathogenicity of RABV in mice. Furthermore, we found that TRIM72 over-expression effectively prevents the assembly and/or release of RABV. In terms of the mechanism, TRIM72 promotes the K48-linked ubiquitination of RABV Matrix protein (M), leading to the degradation of M through the proteasome pathway. TRIM72 directly interacts with M and the interaction sites were identified and confirmed through TRIM72-M interaction model construction and mutation analysis. Further investigation revealed that the degradation of M induced by TRIM72 was attributed to TRIM72's promotion of ubiquitination at site K195 in M. Importantly, the K195 site was found to be partially conserved among lyssavirus's M proteins, and TRIM72 over-expression induced the degradation of these lyssavirus M proteins. In summary, our study has uncovered a TRIM family protein, TRIM72, that can restrict lyssavirus replication by degrading M, and we have identified a novel ubiquitination site (K195) in lyssavirus M.
Asunto(s)
Rabia , Proteínas de Motivos Tripartitos , Animales , Ratones , Lyssavirus/metabolismo , Lyssavirus/patogenicidad , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas/metabolismo , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Virus de la Rabia/metabolismo , Virus de la Rabia/patogenicidad , Rabia/genéticaRESUMEN
BACKGROUND: Japanese encephalitis virus (JEV) remains a predominant cause of Japanese encephalitis (JE) globally. Its infection is usually accompanied by disrupted bloodâbrain barrier (BBB) integrity and central nervous system (CNS) inflammation in a poorly understood pathogenesis. Productive JEV infection in brain microvascular endothelial cells (BMECs) is considered the initial event of the virus in penetrating the BBB. Type I/III IFN and related factors have been described as negative regulators in CNS inflammation, whereas their role in JE remains ambiguous. METHODS: RNA-sequencing profiling (RNA-seq), real-time quantitative PCR, enzyme-linked immunosorbent assay, and Western blotting analysis were performed to analyze the gene and protein expression changes between mock- and JEV-infected hBMECs. Bioinformatic tools were used to cluster altered signaling pathway members during JEV infection. The shRNA-mediated immune factor-knockdown hBMECs and the in vitro transwell BBB model were utilized to explore the interrelation between immune factors, as well as between immune factors and BBB endothelial integrity. RESULTS: RNA-Seq data of JEV-infected hBMECs identified 417, 1256, and 2748 differentially expressed genes (DEGs) at 12, 36, and 72 h post-infection (hpi), respectively. The altered genes clustered into distinct pathways in gene ontology (GO) terms and KEGG pathway enrichment analysis, including host antiviral immune defense and endothelial cell leakage. Further investigation revealed that pattern-recognition receptors (PRRs, including TLR3, RIG-I, and MDA5) sensed JEV and initiated IRF/IFN signaling. IFNs triggered the expression of interferon-induced proteins with tetratricopeptide repeats (IFITs) via the JAK/STAT pathway. Distinct PRRs exert different functions in barrier homeostasis, while treatment with IFN (IFN-ß and IFN-λ1) in hBMECs stabilizes the endothelial barrier by alleviating exogenous destruction. Despite the complex interrelationship, IFITs are considered nonessential in the IFN-mediated maintenance of hBMEC barrier integrity. CONCLUSIONS: This research provided the first comprehensive description of the molecular mechanisms of hostâpathogen interplay in hBMECs responding to JEV invasion, in which type I/III IFN and related factors strongly correlated with regulating the hBMEC barrier and restricting JEV infection. This might help with developing an attractive therapeutic strategy in JE.
Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Virus de la Encefalitis Japonesa (Subgrupo) , Encefalitis Japonesa , Interferón Tipo I , Humanos , Encefalitis Japonesa/genética , Barrera Hematoencefálica , Interferón lambda , Células Endoteliales , Quinasas Janus , Factores de Transcripción STAT , Transducción de Señal , InflamaciónRESUMEN
Rabies, caused by rabies virus (RABV), is a widespread zoonosis that is nearly 100% fatal. Alteration of the metabolic environment affects viral replication and the immune response during viral infection. In this study, glucose uptake was increased in mouse brains at the late stage of infection with different RABV strains (lab-attenuated CVS strain and wild-type DRV strain). To illustrate the mechanism underlying glucose metabolism alteration, comprehensive analysis of lysine acetylation and target analysis of energy metabolites in mouse brains infected with CVS and DRV strains were performed. A total of 156 acetylated sites and 115 acetylated proteins were identified as significantly different during RABV infection. Compared to CVS- and mock-infected mice, the lysine acetylation levels of glycolysis and tricarboxylic acid (TCA) cycle enzymes were decreased, and enzyme activity was upregulated in DRV-infected mouse brains. Metabolomic analysis revealed high levels of oxaloacetate (OAA) in RABV-infected mouse brains. Specifically, the OAA level in CVS-infected mouse brains was higher than that in DRV-infected mouse brains, which contributed to the enhancement of the metabolic rate at the substrate level. Finally, we confirmed that OAA could reduce excessive neuroinflammation in CVS-infected mouse brains by inhibiting JNK and P38 phosphorylation. Taken together, this study provides fresh insight into the different strategies the host adapts to regulate glucose metabolism for energy requirements after different RABV strain infections and suggests that OAA treatment is a strategy to prevent neural damage during RABV infection. IMPORTANCE Both viral replication and the host immune response are highly energy dependent. It is important to understand how the rabies virus affects energy metabolism in the brain. Glucose is the direct energy source for cell metabolism. Previous studies have revealed that there is some association between acetylation and metabolic processes. In this study, comprehensive protein acetylation and glucose metabolism analysis were conducted to compare glucose metabolism in mouse brains infected with different RABV strains. Our study demonstrates that the regulation of enzyme activity by acetylation and OAA accumulation at the substrate level are two strategies for the host to respond to energy requirements after RABV infection. Our study also indicates the role OAA could play in neuronal protection by suppressing excessive neuroinflammation.
Asunto(s)
Encéfalo/metabolismo , Glucosa/metabolismo , Virus de la Rabia/patogenicidad , Rabia/metabolismo , Acetilación , Animales , Encéfalo/efectos de los fármacos , Encéfalo/inmunología , Encéfalo/virología , Metabolismo Energético , Inflamación , Ratones , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Ácido Oxaloacético/metabolismo , Ácido Oxaloacético/uso terapéutico , Proteoma/metabolismo , Rabia/tratamiento farmacológico , Rabia/virologíaRESUMEN
Rabies virus (RABV) infection can initiate the host immune defence response and induce an antiviral state characterized by the expression of interferon (IFN)-stimulated genes (ISGs), among which the family of genes of IFN-induced protein with tetratricopeptide repeats (Ifits) are prominent representatives. Herein, we demonstrated that the mRNA and protein levels of Ifit1, Ifit2 and Ifit3 were highly increased in cultured cells and mouse brains after RABV infection. Recombinant RABV expressing Ifit3, designated rRABV-Ifit3, displayed a lower pathogenicity than the parent RABV in C57BL/6 mice after intramuscular administration, and Ifit3-deficient mice exhibited higher susceptibility to RABV infection and higher mortality during RABV infection. Moreover, compared with their individual expressions, co-expression of Ifit2 and Ifit3 could more effectively inhibit RABV replication in vitro. These results indicate that murine Ifit3 plays an essential role in restricting the replication and reducing the pathogenicity of RABV. Ifit3 acts synergistically with Ifit2 to inhibit RABV replication, providing further insight into the function and complexity of the Ifit family.
Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/metabolismo , Virus de la Rabia/fisiología , Rabia/virología , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Encéfalo/metabolismo , Encéfalo/virología , Línea Celular , Femenino , Humanos , Inmunidad Innata , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Rabia/inmunología , Virus de la Rabia/patogenicidad , Transcriptoma , Carga Viral , Replicación ViralRESUMEN
Peroxynitrite is an ion acting as a powerful oxidant and nucleophile, which plays a key role in the inflammation and aging process by nitrating tyrosine or tryptophan residues of the proteins. Nitration of a target protein is considered to be a proper method to study the behavioral change of the proteins being nitrated. The commonly used methods for peroxynitrite preparation in vitro usually contain high concentration of sodium hydroxide, which easily induces hydrolysis of target proteins. Accordingly, the method for peroxynitrite preparation was optimized in vitro by changing the sequence of hydrochloric acid and sodium hydroxide added. After different amount of hydrochloric acid added to the system following sodium nitrite, peroxynitrite can be yielded in a concentration up to 60 mM with sodium hydroxide as low as 17 mM. More importantly, biological activity of the target protein was well maintained after protein nitration since low sodium hydroxide was used.
Asunto(s)
Bioquímica/métodos , Nitratos/metabolismo , Ácido Peroxinitroso/metabolismo , Proteínas/metabolismo , Hidróxido de Sodio/farmacología , Animales , Células CHO , Quimiocina CCL2/metabolismo , Cricetinae , CricetulusRESUMEN
Protein-protein interaction (PPI) network maintains proper function of all organisms. Simple high-throughput technologies are desperately needed to delineate the landscape of PPI networks. While recent state-of-the-art yeast two-hybrid (Y2H) systems improved screening efficiency, either individual colony isolation, library preparation arrays, gene barcoding or massive sequencing are still required. Here, we developed a recombination-based 'library vs library' Y2H system (RLL-Y2H), by which multi-library screening can be accomplished in a single pool without any individual treatment. This system is based on the phiC31 integrase-mediated integration between bait and prey plasmids. The integrated fragments were digested by MmeI and subjected to deep sequencing to decode the interaction matrix. We applied this system to decipher the trans-kingdom interactome between Mycobacterium tuberculosis and host cells and further identified Rv2427c interfering with the phagosome-lysosome fusion. This concept can also be applied to other systems to screen protein-RNA and protein-DNA interactions and delineate signaling landscape in cells.
Asunto(s)
Proteínas Relacionadas con la Autofagia/genética , Proteínas Bacterianas/genética , Biblioteca de Genes , Ensayos Analíticos de Alto Rendimiento , Interacciones Huésped-Patógeno/genética , Mycobacterium tuberculosis/genética , Animales , Proteínas Relacionadas con la Autofagia/clasificación , Proteínas Relacionadas con la Autofagia/metabolismo , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/metabolismo , Sistemas CRISPR-Cas , Desoxirribonucleasas de Localización Especificada Tipo II/química , Edición Génica/métodos , Genes Reporteros , Secuenciación de Nucleótidos de Alto Rendimiento , Integrasas/genética , Integrasas/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Ratones , Mycobacterium tuberculosis/metabolismo , Fagosomas/metabolismo , Fagosomas/microbiología , Plásmidos/química , Plásmidos/metabolismo , Mapeo de Interacción de Proteínas/métodos , Células RAW 264.7 , Recombinación Genética , Siphoviridae/química , Técnicas del Sistema de Dos Híbridos , Proteína Fluorescente RojaRESUMEN
Canine distemper (CD) causes gastrointestinal and respiratory and/or neurological signs and results in high morbidity and mortality, remaining a threat to carnivores around the world. Live-attenuated vaccines have been widely used to reduce the number of CD outbreaks, but efforts are still needed to improve immune efficiency. Interleukin-7 (IL-7) has been reported to boost host immunity by recruiting follicle helper T (TFH) or germinal center (GC) B cells. Here, we constructed a recombinant canine distemper virus (rCDV) by reverse genetics and evaluated the properties of six intergenic sites for insertion of a foreign gene. We found that the P/M intergenic region was the optimal site to insert a foreign gene into the CDV genome. The effect of overexpressing IL-7 on rCDV immunogenicity was then evaluated in a mouse model. We found that mice immunized with rCDV-IL7 could not significantly enhance the maturation of dendritic cells (DCs) but significantly facilitated the generation of TFH cells, GC B cells and plasma cells (PCs), as well as the formation of GCs, consequently enhancing the production of CDV-specific neutralizing antibodies and total IgG. Together, these results suggested that the overexpression of IL-7 by rCDV could enhance humoral responses by activating the TFH-GC B-PC axis, which will help to improve vaccines for CD.
Asunto(s)
Virus del Moquillo Canino/inmunología , Moquillo/inmunología , Inmunidad Humoral/inmunología , Interleucina-7/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Linfocitos B/inmunología , Chlorocebus aethiops , Perros , Femenino , Centro Germinal/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos ICR , Linfocitos T Colaboradores-Inductores/inmunología , Vacunación/métodos , Vacunas Atenuadas/inmunología , Células Vero , Vacunas Virales/inmunologíaRESUMEN
Rabies, caused by rabies virus (RABV), is a fatal zoonosis, which still poses a threat to public health in most parts of the world. Glycoprotein of RABV is the only viral surface protein, which is critical for the induction of virus-neutralizing antibodies (VNA). In order to improve the production of VNA, recombinant RABVs containing two copies of G gene and codon-optimized G gene were constructed by using reverse genetics, named LBNSE-dG and LBNSE-dOG, respectively. After being inoculated into the mouse brains, LBNSE-dOG induced more apoptosis and recruited more inflammatory cells than LBNSE-dG and LBNSE, resulting in reduced virulence in vivo. After intramuscular (im) immunization in mice, LBNSE-dOG promoted the formation of germinal centres (GCs), the recruitment of GC B cells and the generation of antibody-secreting cells (ASCs) in the draining lymph nodes (LNs). Consistently, LBNSE-dOG boosted the production of VNA and provided better protection against lethal RABV challenge than LBNSE-dG and LBNSE when it was used as both live and inactivated vaccines. Our results demonstrate that the codon-optimized RABV LBNSE-dOG displays attenuated pathogenicity and enhanced immunogenicity, therefore it could be a potential candidate for the next generation of rabies vaccines.
Asunto(s)
Codón/genética , Glicoproteínas/genética , Glicoproteínas/inmunología , Inmunidad Humoral , Virus de la Rabia/inmunología , Rabia/inmunología , Proteínas Virales/genética , Proteínas Virales/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Femenino , Glicoproteínas/administración & dosificación , Humanos , Ratones , Ratones Endogámicos ICR , Rabia/prevención & control , Rabia/virología , Vacunas Antirrábicas/administración & dosificación , Vacunas Antirrábicas/genética , Vacunas Antirrábicas/inmunología , Virus de la Rabia/genética , Proteínas Virales/administración & dosificaciónRESUMEN
Coronaviruses pose serious health threats to humans and other animals. Understanding the mechanisms of their replication has important implications for global health and economic stability. Nonstructural protein 9 (nsp9) is an essential RNA binding protein for coronavirus replication. However, the mechanisms of the dimerization and nucleic acid binding of nsp9 remain elusive. Here, we report four crystal structures, including wild-type porcine delta coronavirus (PDCoV) nsp9, PDCoV nsp9-ΔN7 (N-terminal 7 amino acids deleted), wild-type porcine epidemic diarrhea virus (PEDV) nsp9, and PEDV nsp9-C59A mutant. These structures reveal the diverse dimerization forms of coronavirus nsp9. We first found that the N-finger of nsp9 from PDCoV plays a critical role in dimerization. Meanwhile, PEDV nsp9 is distinguished by the presence of a disulfide bond in the dimer interface. Interestingly, size exclusion chromatography and analytical ultracentrifugation analyses indicate that the PDCoV nsp9-ΔN7 and PEDV nsp9-C59A mutants are monomeric in solution. In addition, electrophoretic mobility shift assays and microscale thermophoresis analysis indicate that the monomeric forms of PDCoV nsp9 and PEDV nsp9 still have nucleic acid binding affinity, although it is lower than that of the wild type. Our results show that the diverse dimerization forms of coronavirus nsp9 proteins enhance their nucleic acid binding affinity.IMPORTANCE Coronaviruses cause widespread respiratory, gastrointestinal, and central nervous system diseases in humans and other animals, threatening human health and causing economic loss. Coronavirus nsp9, a member of the replication complex, is an important RNA binding subunit in the RNA-synthesizing machinery of all coronaviruses. However, the mechanisms of the dimerization and nucleic acid binding of nsp9 remain elusive. In this study we determined the nsp9 crystal structures of PDCoV and PEDV. We first found that the N-finger of nsp9 from PDCoV plays a critical role in dimerization. Meanwhile, PEDV nsp9 is distinguished by the presence of a disulfide bond in the dimer interface. This study provides a structural and functional basis for understanding the mechanism of dimerization and shows that the diverse dimerization modes of coronavirus nsp9 proteins enhance their nucleic acid binding affinity. Importantly, these findings may provide a new insight for antiviral drug development.
Asunto(s)
Coronavirus/fisiología , Multimerización de Proteína , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/metabolismo , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , Animales , Cristalografía por Rayos X , Modelos Moleculares , Ácidos Nucleicos , Conformación Proteica , PorcinosRESUMEN
Loop-mediated isothermal amplification (LAMP) is a widely used isothermal nucleic acid amplification method. Here we developed a new closed-tube colorimetric method for judging LAMP with a novel metal indicator. First, the metal indicator, acid chrome blue K (ACBK), was evaluated in the LAMP reaction with various combinations of reaction reagents, such as reaction buffer, dNTP mixtures, primer mixtures, or Mg2+. We found that the solution color of the LAMP reaction with ACBK changed from red to blue based on a decrease in the Mg2+ concentration in the reaction solution. We then optimized the LAMP with ACBK method for detecting the Cauliflower Mosaic Virus 35S promoter. Further, the specificity of the new colorimetric assay using ACBK in the LAMP reaction for detecting the 35S promoter was tested with diverse transgenic events in different crops, and the sensitivity threshold of the assay was â¼50 copies for transgenic rice genomic DNA and 100 ng of 0.1 % DNA from rice, soybean, rapeseed, and maize. Finally, the applicability of the LAMP assay was successfully validated using practical maize samples. All the detection results could be easily discerned either by UV-vis spectroscopy or the naked eye. Graphical Abstract The visual detect LAMP amplification by the addition of ACBK as a signal indicator. The color of the LAMP-ACBK solution turned from red to blue as the concentration of free Mg2+ decreases. The detection results could be easily discerned either by UV-vis spectroscopy or the naked eye.
Asunto(s)
Colorimetría/métodos , Metales/química , Regiones Promotoras Genéticas , Caulimovirus/genética , Electroforesis en Gel de Agar , Límite de Detección , Plantas Modificadas Genéticamente/genética , Reacción en Cadena de la Polimerasa , Espectrofotometría UltravioletaRESUMEN
Rabies remains a major public health threat around the world. Once symptoms appear, there is no effective treatment to prevent death. In this work, we tested a recombinant parainfluenza virus 5 (PIV5) strain expressing the glycoprotein (G) of rabies (PIV5-G) as a therapy for rabies virus infection: we have found that PIV5-G protected mice as late as 6 days after rabies virus infection. PIV5-G is a promising vaccine for prevention and treatment of rabies virus infection.
Asunto(s)
Vectores Genéticos/genética , Virus de la Parainfluenza 5/genética , Vacunas Antirrábicas/administración & dosificación , Virus de la Rabia/inmunología , Rabia/prevención & control , Proteínas del Envoltorio Viral/administración & dosificación , Animales , Anticuerpos Antivirales/inmunología , Expresión Génica , Vectores Genéticos/metabolismo , Humanos , Ratones , Virus de la Parainfluenza 5/metabolismo , Rabia/inmunología , Rabia/virología , Vacunas Antirrábicas/genética , Vacunas Antirrábicas/inmunología , Virus de la Rabia/genética , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunologíaRESUMEN
Rabies, caused by lyssavirus rabies (Rabies lyssavirus, RABV), is a fatal disease among humans and almost all warm-blooded animals. In this study, we found that RABV infection induces the up-regulation of receptor transporter protein 4 (RTP4) in mouse brains and different cells of nervous tissue. Over-expression of RTP4 reduces the viral titer of RABV in different neuronal cells. Furthermore, a recombinant RABV expressing RTP4, named rRABV-RTP4, was constructed and displayed a lower viral titer in different neuronal cells due to the expression of RTP4. Moreover, the survival rates of mice infected with rRABV-RTP4 were significantly higher than those of mice infected with parent virus rRABV or control virus rRABV-RTP4(-). In terms of mechanism, RTP4 could bind viral genomic RNA (vRNA) of RABV, and suppress the whole viral genome amplification. In addition, we found that the zinc finger domain (ZFD) of RTP4 exerts the antiviral function by truncation analysis, and an important amino acids site (C95) in the RTP4 3CxxC motif which is essential for its antiviral function was identified by mutation analysis. This study contributes to our understanding of how RTP4 or other RTP proteins play a role in defense against the invasion of RABV or other viruses.
Asunto(s)
ARN Viral , Virus de la Rabia , Rabia , Animales , Humanos , Ratones , Encéfalo/virología , Línea Celular , Genoma Viral , Lyssavirus/genética , Neuronas/virología , Rabia/virología , Virus de la Rabia/genética , Virus de la Rabia/fisiología , Virus de la Rabia/patogenicidad , ARN Viral/genética , Replicación ViralRESUMEN
Lyssavirus is a kind of neurotropic pathogen that needs to evade peripheral host immunity to enter the central nervous system to accomplish infection. NLRP3 inflammasome activation is essential for the host to defend against pathogen invasion. This study demonstrates that the matrix protein (M) of lyssavirus can inhibit both the priming step and the activation step of NLRP3 inflammasome activation. Specifically, M of lyssavirus can compete with NEK7 for binding to NLRP3, which restricts downstream apoptosis-associated speck-like protein containing a CARD (ASC) oligomerization. The serine amino acid at the 158th site of M among lyssavirus is critical for restricting ASC oligomerization. Moreover, recombinant lab-attenuated lyssavirus rabies (rabies lyssavirus [RABV]) with G158S mutation at M decreases interleukin-1ß (IL-1ß) production in bone-marrow-derived dendritic cells (BMDCs) to facilitate lyssavirus invasion into the brain thereby elevating pathogenicity in mice. Taken together, this study reveals a common mechanism by which lyssavirus inhibits NLRP3 inflammasome activation to evade host defenses.
Asunto(s)
Células Dendríticas , Inflamasomas , Interleucina-1beta , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR , Proteínas de la Matriz Viral , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Animales , Inflamasomas/metabolismo , Inflamasomas/inmunología , Ratones , Proteínas de la Matriz Viral/metabolismo , Humanos , Interleucina-1beta/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/virología , Lyssavirus/metabolismo , Lyssavirus/inmunología , Quinasas Relacionadas con NIMA/metabolismo , Unión Proteica , Proteínas Adaptadoras de Señalización CARD/metabolismo , Células HEK293RESUMEN
Human brain microvascular endothelial cells (hBMECs) are the main component cells of the blood-brain barrier (BBB) and play a crucial role in responding to viral infections to prevent the central nervous system (CNS) from viral invasion. Interferon-inducible transmembrane protein 1 (IFITM1) is a multifunctional membrane protein downstream of type-I interferon. In this study, we discovered that hIFITM1 expression was highly upregulated in hBMECs during Japanese encephalitis virus (JEV) infection. Depletion of hIFITM1 with CRISPR/Cas9 in hBMECs enhanced JEV replication, while overexpression of hIFITM1 restricted the viruses. Additionally, overexpression of hIFITM1 promoted the monolayer formation of hBMECs with a better integrity and a higher transendothelial electrical resistance (TEER), and reduced the penetration of JEV across the BBB. However, the function of hIFITM1 is governed by palmitoylation. Mutations of palmitoylation residues in conserved CD225 domain of hIFITM1 impaired its antiviral capacity. Moreover, mutants retained hIFITM1 in the cytoplasm and lessened its interaction with tight junction protein Occludin. Taken together, palmitoylation of hIFITM1 is essential for its antiviral activity in hBMECs, and more notably, for the maintenance of BBB homeostasis.
Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Humanos , Barrera Hematoencefálica/metabolismo , Virus de la Encefalitis Japonesa (Especie)/genética , Células Endoteliales/metabolismo , Lipoilación , Encefalitis Japonesa/genética , Antivirales/metabolismo , Interferones/metabolismoRESUMEN
Technology for spatial multi-omics aids the discovery of new insights into cellular functions and disease mechanisms. Here we report the development and applicability of multi-omics in situ pairwise sequencing (MiP-seq), a method for the simultaneous detection of DNAs, RNAs, proteins and biomolecules at subcellular resolution. Compared with other in situ sequencing methods, MiP-seq enhances decoding capacity and reduces sequencing and imaging costs while maintaining the efficacy of detection of gene mutations, allele-specific expression and RNA modifications. MiP-seq can be integrated with in vivo calcium imaging and Raman imaging, which enabled us to generate a spatial multi-omics atlas of mouse brain tissues and to correlate gene expression with neuronal activity and cellular biochemical fingerprints. We also report a sequential dilution strategy for resolving optically crowded signals during in situ sequencing. High-throughput in situ pairwise sequencing may facilitate the multidimensional analysis of molecular and functional maps of tissues.
Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Animales , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Ratones , Encéfalo/metabolismo , Calcio/metabolismo , Genómica/métodos , MultiómicaRESUMEN
In the unprecedented single-cell sequencing and spatial multiomics era of biology, fluorescence in situ hybridization (FISH) technologies with higher sensitivity and robustness, especially for detecting short RNAs and other biomolecules, are greatly desired. Here, we develop the robust multiplex π-FISH rainbow method to detect diverse biomolecules (DNA, RNA, proteins, and neurotransmitters) individually or simultaneously with high efficiency. This versatile method is successfully applied to detect gene expression in different species, from microorganisms to plants and animals. Furthermore, we delineate the landscape of diverse neuron subclusters by decoding the spatial distribution of 21 marker genes via only two rounds of hybridization. Significantly, we combine π-FISH rainbow with hybridization chain reaction to develop π-FISH+ technology for short nucleic acid fragments, such as microRNA and prostate cancer anti-androgen therapy-resistant marker ARV7 splicing variant in circulating tumour cells from patients. Our study provides a robust biomolecule in situ detection technology for spatial multiomics investigation and clinical diagnosis.
Asunto(s)
MicroARNs , Ácidos Nucleicos , Neoplasias de la Próstata , Humanos , Masculino , Animales , Hibridación Fluorescente in Situ/métodos , MicroARNs/genética , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genéticaRESUMEN
IMPORTANCE: African swine fever (ASF), caused by African swine fever virus (ASFV), has become a major crisis for the pork industry in recent years. The mechanism for ASFV pathology and the clinical symptoms difference of ASF between domestic pigs and reservoir hosts remain to be elucidated. We deciphered the comprehensive protein-protein interaction (PPI) network between ASFV and host immune pathways. The intensive PPI network contained both ASFV-host immune pathway PPI and ASFV-ASFV PPI information, providing a comprehensive ASFV-host interaction landscape. Furthermore, the ASFV-host PPI difference between domestic pigs and warthogs was explored, which will be instructive for exploring essential candidates involved in ASFV pathology. Moreover, we screened the inhibitory effect of ASFV proteins in the PPI with cGAS-STING pathway on IFN-I and NF-κB, further providing possible functions of ASFV-host PPI network in innate immune regulation.
Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Interferón Tipo I , Porcinos , Animales , Fiebre Porcina Africana/metabolismo , Sus scrofa , FN-kappa B/metabolismo , Interferón Tipo I/metabolismoRESUMEN
Mumps virus (MuV) is highly neurotropic and neurovirulent, hence, the neurovirulence of virus seeds used in the production of mumps vaccines must be tested. The previous neurovirulence evaluation method involves measuring the area of the cavity in the Lewis neonatal rat brain caused by MuV through paraffin sectioning and hematoxylin-eosin (HE) staining. However, the processes of paraffin sectioning and HE staining are time consuming and complicated. To solve this problem, in this study, a vibratome sectioning system was first deployed to evaluate MuV neurovirulence in the rat brain instead of paraffin sectioning and HE staining. The results showed that the vibratome sectioning method could assess the neurovirulence potential of MuV more objectively and efficiently. In addition, the effects of different MuV doses and the ages of the rats in days on this evaluation method were explored. The results indicate that MuV at no less than 10 50 % cell culture infective dose (CCID50) could cause obvious cavity formation in 1-day-old rat brains. The neonatal rat model developed in this study could evaluate the neurovirulence of different MuV strains with high sensitivity and good repeatability.
Asunto(s)
Virus de la Parotiditis , Paperas , Animales , Ratas , Ratas Wistar , Parafina , Eosina Amarillenta-(YS) , Hematoxilina , Ratas Endogámicas Lew , Virulencia , Vacuna contra la ParotiditisRESUMEN
The establishment of Japanese encephalitis virus (JEV) infection in brain microvascular endothelial cells (BMECs) is thought to be a critical step to induce viral encephalitis with compromised blood-brain barrier (BBB), and the mechanisms involved in this process are not completely understood. In this study, we found that epidermal growth factor receptor (EGFR) is related to JEV escape from interferon-related host innate immunity based on a STRING analysis of JEV-infected primary human brain microvascular endothelial cells (hBMECs) and mouse brain. At the early phase of the infection processes, JEV induced the phosphorylation of EGFR. In JEV-infected hBMECs, a rapid internalization of EGFR that co-localizes with the endosomal marker EEA1 occurred. Using specific inhibitors to block EGFR, reduced production of viral particles was observed. Similar results were also found in an EGFR-KO hBMEC cell line. Even though the process of viral infection in attachment and entry was not noticeably influenced, the induction of IFNs in EGFR-KO hBMECs was significantly increased, which may account for the decreased viral production. Further investigation demonstrated that EGFR downstream cascade ERK, but not STAT3, was involved in the antiviral effect of IFNs, and a lowered viral yield was observed by utilizing the specific inhibitor of ERK. Taken together, the results revealed that JEV induces EGFR activation, leading to a suppression of interferon signaling and promotion of viral replication, which could provide a potential target for future therapies for the JEV infection.
RESUMEN
The nervous and immune systems are closely entwined to maintain the immune balance in health and disease. Here, we showed that LPS can activate suprarenal and celiac ganglia (SrG-CG) neurons and upregulate NPY expression in rats. Single-cell sequencing analysis revealed that knockdown of the NPY gene in SrG-CG altered the proliferation and activation of splenic lymphocytes. In a neuron and splenocyte coculture system and in vivo experiments, neuronal NPY in SrG-CG attenuated the splenic immune response. Notably, we demonstrated that neuronal NPF in Drosophila exerted a conservative immunomodulatory effect. Moreover, numerous SNPs in NPY and its receptors were significantly associated with human autoimmune diseases, which was further supported by the autoimmune disease patients and mouse model experiments. Together, we demonstrated that NPY is an ancient language for nervous-immune system crosstalk and might be utilized to alleviate inflammatory storms during infection and to modulate immune balance in autoimmune diseases.