RESUMEN
The family Rhabdoviridae includes viruses with a negative-sense RNA genome. This family is divided into four subfamilies, and until recently, the subfamily Betarhabdovirinae, encompassing all plant-associated rhabdoviruses, was further divided into six genera. Here, we report the creation of two new genera within the subfamily Betarhabdovirinae - Alphagymnorhavirus and Betagymnorhavirus - to include recently described gymnosperm-associated viruses. The genus Alphagymnorhavirus includes nine species, while the genus Betagymnorhavirus includes only one species. Phylogenetic analysis indicated that these viruses form two well-supported clades that are clustered with the varicosaviruses, which have bisegmented genomes. In contrast, the 10 viruses included in the newly created genera have the distinctive feature that they have an unsegmented genome encoding five or six proteins. The creation of the genera Alphagymnorhavirus and Betagymnorhavirus has been ratified by the International Committee on Taxonomy of Viruses (ICTV).
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Genoma Viral , Filogenia , Enfermedades de las Plantas , Rhabdoviridae , Rhabdoviridae/genética , Rhabdoviridae/clasificación , Rhabdoviridae/aislamiento & purificación , Genoma Viral/genética , Enfermedades de las Plantas/virología , Cycadopsida/virología , ARN Viral/genéticaAsunto(s)
Epidemiología , Urgencias Médicas , Encefalitis , Rhabdoviridae , Mpox , Orthobunyavirus , Vesiculovirus , LepraRESUMEN
PHD1 is a member of the prolyl hydroxylase domain protein (PHD1-4) family, which plays a prominent role in the post-translational modification of its target proteins by hydroxylating proline residues. The best-characterized targets of PHD1 are hypoxia-inducible factor α (HIF-1α and HIF-2α), two master regulators of the hypoxia signaling pathway. In this study, we show that zebrafish phd1 positively regulates mavs-mediated antiviral innate immunity. Overexpression of phd1 enhances the cellular antiviral response. Consistently, zebrafish lacking phd1 are more susceptible to spring viremia of carp virus infection. Further assays indicate that phd1 interacts with mavs through the C-terminal transmembrane domain of mavs and promotes mavs aggregation. In addition, zebrafish phd1 attenuates K48-linked polyubiquitination of mavs, leading to stabilization of mavs. However, the enzymatic activity of phd1 is not required for phd1 to activate mavs. In conclusion, this study reveals a novel function of phd1 in the regulation of antiviral innate immunity.IMPORTANCEPHD1 is a key regulator of the hypoxia signaling pathway, but its role in antiviral innate immunity is largely unknown. In this study, we found that zebrafish phd1 enhances cellular antiviral responses in a hydroxylation-independent manner. Phd1 interacts with mavs through the C-terminal transmembrane domain of mavs and promotes mavs aggregation. In addition, phd1 attenuates K48-linked polyubiquitination of mavs, leading to stabilization of mavs. Zebrafish lacking phd1 are more susceptible to spring viremia of carp virus infection. These findings reveal a novel role for phd1 in the regulation of mavs-mediated antiviral innate immunity.
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Proteínas Adaptadoras Transductoras de Señales , Inmunidad Innata , Infecciones por Rhabdoviridae , Rhabdoviridae , Ubiquitinación , Proteínas de Pez Cebra , Pez Cebra , Animales , Pez Cebra/inmunología , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Infecciones por Rhabdoviridae/inmunología , Hidroxilación , Humanos , Células HEK293 , Transducción de Señal , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/virología , Procesamiento Proteico-PostraduccionalRESUMEN
The production of type I interferon is tightly regulated to prevent excessive immune activation. However, the role of selective autophagy receptor SQSTM1 in this regulation in teleost remains unknown. In this study, we cloned the triploid fish SQSTM1 (3nSQSTM1), which comprises 1371 nucleotides, encoding 457 amino acids. qRT-PCR data revealed that the transcript levels of SQSTM1 in triploid fish were increased both in vivo and in vitro following spring viraemia of carp virus (SVCV) infection. Immunofluorescence analysis confirmed that 3nSQSTM1 was mainly distributed in the cytoplasm. Luciferase reporter assay results showed that 3nSQSTM1 significantly blocked the activation of interferon promoters induced by 3nMDA5, 3nMAVS, 3nTBK1, and 3nIRF7. Co-immunoprecipitation assays further confirmed that 3nSQSTM1 could interact with both 3nTBK1 and 3nIRF7. Moreover, upon co-transfection, 3nSQSTM1 significantly inhibited the antiviral activity mediated by TBK1 and IRF7. Mechanistically, 3nSQSTM1 decreased the TBK1 phosphorylation and its interaction with 3nIRF7, thereby suppressing the subsequent antiviral response. Notably, we discovered that 3nSQSTM1 also interacted with SVCV N and P proteins, and these viral proteins may exploit 3nSQSTM1 to further limit the host's antiviral innate immune responses. In conclusion, our study demonstrates that 3nSQSTM1 plays a pivotal role in negatively regulating the interferon signaling pathway by targeting 3nTBK1 and 3nIRF7.
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Carpas , Enfermedades de los Peces , Proteínas de Peces , Inmunidad Innata , Factor 7 Regulador del Interferón , Infecciones por Rhabdoviridae , Rhabdoviridae , Animales , Inmunidad Innata/genética , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/virología , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Factor 7 Regulador del Interferón/genética , Factor 7 Regulador del Interferón/inmunología , Rhabdoviridae/fisiología , Infecciones por Rhabdoviridae/inmunología , Infecciones por Rhabdoviridae/veterinaria , Carpas/inmunología , Carpas/genética , Proteína Sequestosoma-1/genética , Proteína Sequestosoma-1/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/inmunología , Proteínas Serina-Treonina Quinasas/metabolismo , Regulación de la Expresión Génica/inmunología , Transducción de Señal/inmunología , Triploidía , Filogenia , Secuencia de Aminoácidos , Alineación de Secuencia/veterinaria , Perfilación de la Expresión Génica/veterinariaRESUMEN
Spring viremia of carp virus (SVCV) is a rhabdovirus that primarily infects cyprinid finfishes and causes a disease notifiable to the World Organization for Animal Health. Amphibians, which are sympatric with cyprinids in freshwater ecosystems, are considered non-permissive hosts of rhabdoviruses. The potential host range expansion of SVCV in an atypical host species was evaluated by testing the susceptibility of amphibians native to the Pacific Northwest. Larval long-toed salamanders Ambystoma macrodactylum and Pacific tree frog Pseudacris regilla tadpoles were exposed to SVCV strains from genotypes Ia, Ib, Ic, or Id by either intraperitoneal injection, immersion, or cohabitation with virus-infected koi Cyprinus rubrofuscus. Cumulative mortality was 100% for salamanders injected with SVCV, 98-100% for tadpoles exposed to virus via immersion, and 0-100% for tadpoles cohabited with SVCV-infected koi. Many of the animals that died exhibited clinical signs of disease and SVCV RNA was found by in situ hybridization in tissue sections of immersion-exposed tadpoles, particularly in the cells of the gastrointestinal tract and liver. SVCV was also detected by plaque assay and RT-qPCR testing in both amphibian species regardless of the virus exposure method, and viable virus was detected up to 28 days after initial exposure. Recovery of infectious virus from naïve tadpoles cohabited with SVCV-infected koi further demonstrated that SVCV transmission can occur between classes of ectothermic vertebrates. Collectively, these results indicated that SVCV, a fish rhabdovirus, can be transmitted to and cause lethal disease in two amphibian species. Therefore, members of all five of the major vertebrate groups (mammals, birds, reptiles, fish, and amphibians) appear to be vulnerable to rhabdovirus infections. Future research studying potential spillover and spillback infections of aquatic rhabdoviruses between foreign and domestic amphibian and fish species will provide insights into the stressors driving novel interclass virus transmission events.
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Enfermedades de los Peces , Larva , Infecciones por Rhabdoviridae , Rhabdoviridae , Animales , Enfermedades de los Peces/virología , Enfermedades de los Peces/transmisión , Infecciones por Rhabdoviridae/veterinaria , Infecciones por Rhabdoviridae/virología , Infecciones por Rhabdoviridae/transmisión , Rhabdoviridae/genética , Rhabdoviridae/patogenicidad , Rhabdoviridae/fisiología , Larva/virología , Anfibios/virología , Especificidad del Huésped , Anuros/virología , Genotipo , Ambystoma/virología , Peces/virologíaRESUMEN
Leafhoppers are economically important pests and may serve as vectors for pathogenic viruses that cause substantial crop damage. In this study, using deep transcriptome sequencing, we identified three novel viruses within the order Mononegavirales, including two viruses belonging to the family Rhabdoviridae and one to the family Lispiviridae. The complete genome sequences were obtained via the rapid amplification of cDNA ends and tentatively named Recilia dorsalis rhabdovirus 1 (RdRV1, 14,251 nucleotides, nt), Nephotettix virescens rhabdovirus 1 (NvRV1, 13,726 nt), and Nephotettix virescens lispivirus 1 (NvLV1, 14,055 nt). The results of a phylogenetic analysis and sequence identity comparison suggest that RdRV1 and NvRV1 represent novel species within the family Rhabdoviridae, while NvLV1 is a new virus belonging to the family Lispiviridae. As negative-sense single-strand RNA viruses, RdRV1 and NvRV1 contain the conserved transcription termination signal and intergenic trinucleotides in the non-transcribed region. Intergenomic sequence and transcriptome profile analyses suggested that all these genes were co-transcriptionally expressed in these viral genomes, facilitated by specific intergenic trinucleotides and putative transcription initiation sequences.
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Genoma Viral , Genómica , Hemípteros , Mononegavirales , Filogenia , Rhabdoviridae , Animales , Mononegavirales/genética , Mononegavirales/clasificación , Rhabdoviridae/genética , Rhabdoviridae/clasificación , Hemípteros/virología , Genómica/métodos , ARN Viral/genética , Secuenciación de Nucleótidos de Alto Rendimiento , TranscriptomaRESUMEN
Rhabdoviral vectors can induce lysis of cancer cells. While studied almost exclusively at 37 °C, viruses are subject to a range of temperatures in vivo, including temperatures ≤31 °C. Despite potential implications, the effect of temperatures <37 °C on the performance of rhabdoviral vectors is unknown. We investigated the effect of low anatomical temperatures on two rhabdoviruses, vesicular stomatitis virus (VSV) and Maraba virus (MG1). Using a metabolic resazurin assay, VSV- and MG1-mediated oncolysis was characterized in a panel of cell lines at 28, 31, 34 and 37 °C. The oncolytic ability of both viruses was hindered at 31 and 28 °C. Cold adaptation of both viruses was attempted as a mitigation strategy. Viruses were serially passaged at decreasing temperatures in an attempt to induce mutations. Unfortunately, the cold-adaptation strategies failed to potentiate the oncolytic activity of the viruses at temperatures <37 °C. Interestingly, we discovered that viral replication was unaffected at low temperatures despite the abrogation of oncolytic activity. In contrast, the proliferation of cancer cells was reduced at low temperatures. Equivalent oncolytic effects could be achieved if cells at low temperatures were treated with viruses for longer times. This suggests that rhabdovirus-mediated oncolysis could be compromised at low temperatures in vivo where therapeutic windows are limited.
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Frío , Virus Oncolíticos , Rhabdoviridae , Replicación Viral , Humanos , Rhabdoviridae/fisiología , Rhabdoviridae/genética , Animales , Virus Oncolíticos/fisiología , Virus Oncolíticos/genética , Vesiculovirus/fisiología , Vesiculovirus/genética , Viroterapia Oncolítica/métodos , Línea Celular , Vectores Genéticos/genética , Línea Celular Tumoral , TemperaturaRESUMEN
Spring viremia of carp virus (SVCV) has a broad fish host spectrum and is responsible for a disease that generally affects juvenile fishes with a mortality rate of up to 90%. In the absence of treatments or vaccines against SVCV, the search for prophylactic or therapeutic solutions is thus relevant, particularly to identify solutions compatible with mass vaccination. In addition to being a threat to aquaculture and ecosystems, SVCV is a unique pathogen to study virus-host interactions in the zebrafish model. Establishing the first reverse genetics system for SVCV and the design of recombinant SVCV (rSVCV) expressing fluorescent or bioluminescent proteins adds a new dimension for the study of these interactions using innovative imaging techniques. The infection by bath immersion of zebrafish larvae with rSVCV expressing mCherry allows us to define the first SVCV replication sites and the host innate immune responses using different transgenic lines of zebrafish. The fins were found as the main initial sites of infection in both zebrafish and carp, its natural host. Hence, new insights into the physiopathology of SVCV infection have been described. We report that neutrophils are recruited at the sites of infection and persist up to the death of the animal leading to an uncontrolled inflammation correlated with the expression of the pro-inflammatory cytokine IL1ß. Tissue damage was observed at the site of initial replication, a likely consequence of virus-induced injury or the pro-inflammatory response. Interestingly, SVCV infection by bath immersion triggers a persistent pro-inflammatory response rather than activation of the antiviral IFN signaling pathway as observed following intravenous injection, highlighting the importance of the route of infection on the progression of pathogenicity. Thus, this model of zebrafish larvae infection by rSVCV offers new perspectives to study in detail virus-host interactions and to discover new prophylactic or therapeutic solutions.
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Carpas , Enfermedades de los Peces , Infecciones por Rhabdoviridae , Rhabdoviridae , Pez Cebra , Animales , Pez Cebra/virología , Rhabdoviridae/fisiología , Enfermedades de los Peces/virología , Infecciones por Rhabdoviridae/virología , Infecciones por Rhabdoviridae/inmunología , Carpas/virología , Animales Modificados Genéticamente , Modelos Animales de Enfermedad , Inmunidad Innata , ViremiaRESUMEN
Gene regulatory networks (GRNs) are crucial for understanding organismal molecular mechanisms and processes. Construction of GRN in the epithelioma papulosum cyprini (EPC) cells of cyprinid fish by spring viremia of carp virus (SVCV) infection helps understand the immune regulatory mechanisms that enhance the survival capabilities of cyprinid fish. Although many computational methods have been used to infer GRNs, specialized approaches for predicting the GRN of EPC cells following SVCV infection are lacking. In addition, most existing methods focus primarily on gene expression features, neglecting the valuable network structural information in known GRNs. In this study, we propose a novel supervised deep neural network, named MEFFGRN (Matrix Enhancement- and Feature Fusion-based method for Gene Regulatory Network inference), to accurately predict the GRN of EPC cells following SVCV infection. MEFFGRN considers both gene expression data and network structure information of known GRN and introduces a matrix enhancement method to address the sparsity issue of known GRN, extracting richer network structure information. To optimize the benefits of CNN (Convolutional Neural Network) in image processing, gene expression and enhanced GRN data were transformed into histogram images for each gene pair respectively. Subsequently, these histograms were separately fed into CNNs for training to obtain the corresponding gene expression and network structural features. Furthermore, a feature fusion mechanism was introduced to comprehensively integrate the gene expression and network structural features. This integration considers the specificity of each feature and their interactive information, resulting in a more comprehensive and precise feature representation during the fusion process. Experimental results from both real-world and benchmark datasets demonstrate that MEFFGRN achieves competitive performance compared with state-of-the-art computational methods. Furthermore, study findings from SVCV-infected EPC cells suggest that MEFFGRN can predict novel gene regulatory relationships.
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Enfermedades de los Peces , Redes Reguladoras de Genes , Infecciones por Rhabdoviridae , Rhabdoviridae , Animales , Rhabdoviridae/genética , Enfermedades de los Peces/genética , Enfermedades de los Peces/virología , Infecciones por Rhabdoviridae/genética , Infecciones por Rhabdoviridae/virología , Carpas/genética , Carpas/virología , Biología Computacional/métodos , Redes Neurales de la Computación , Cyprinidae/genéticaRESUMEN
BACKGROUND: Spring viremia of carp virus (SVCV) infects a wide range of fish species and causes high mortality rates in aquaculture. This viral infection is characterized by seasonal outbreaks that are temperature-dependent. However, the specific mechanism behind temperature-dependent SVCV infectivity and pathogenicity remains unclear. Given the high sensitivity of the composition of intestinal microbiota to temperature changes, it would be interesting to investigate if the intestinal microbiota of fish could play a role in modulating the infectivity of SVCV at different temperatures. RESULTS: Our study found that significantly higher infectivity and pathogenicity of SVCV infection in zebrafish occurred at relatively lower temperature. Comparative analysis of the intestinal microbiota in zebrafish exposed to high- and low-temperature conditions revealed that temperature influenced the abundance and diversity of the intestinal microbiota in zebrafish. A significantly higher abundance of Parabacteroides distasonis and its metabolite secondary bile acid (deoxycholic acid, DCA) was detected in the intestine of zebrafish exposed to high temperature. Both colonization of Parabacteroides distasonis and feeding of DCA to zebrafish at low temperature significantly reduced the mortality caused by SVCV. An in vitro assay demonstrated that DCA could inhibit the assembly and release of SVCV. Notably, DCA also showed an inhibitory effect on the infectious hematopoietic necrosis virus, another Rhabdoviridae member known to be more infectious at low temperature. CONCLUSIONS: This study provides evidence that temperature can be an important factor to influence the composition of intestinal microbiota in zebrafish, consequently impacting the infectivity and pathogenicity of SVCV. The findings highlight the enrichment of Parabacteroides distasonis and its derivative, DCA, in the intestines of zebrafish raised at high temperature, and they possess an important role in preventing the infection of SVCV and other Rhabdoviridae members in host fish. Video Abstract.
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Bacteroidetes , Enfermedades de los Peces , Microbioma Gastrointestinal , Infecciones por Rhabdoviridae , Rhabdoviridae , Temperatura , Pez Cebra , Animales , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/virología , Infecciones por Rhabdoviridae/virología , Rhabdoviridae/fisiología , Rhabdoviridae/patogenicidad , Bacteroidetes/patogenicidad , Agua , Virus de la Necrosis Hematopoyética Infecciosa/patogenicidadRESUMEN
Le Dantec virus (LDV), assigned to the species Ledantevirus ledantec, genus Ledantevirus, family Rhabdoviridae has been associated with human disease but has gone undetected since the 1970s. We describe the detection of LDV in a human case of undifferentiated fever in Uganda by metagenomic sequencing and demonstrate a serological response using ELISA and pseudotype neutralisation. By screening 997 individuals sampled in 2016, we show frequent exposure to ledanteviruses with 76% of individuals seropositive in Western Uganda, but lower seroprevalence in other areas. Serological cross-reactivity as measured by pseudotype-based neutralisation was confined to ledanteviruses, indicating population seropositivity may represent either exposure to LDV or related ledanteviruses. We also describe the discovery of a closely related ledantevirus in blood from the synanthropic rodent Mastomys erythroleucus. Ledantevirus infection is common in Uganda but is geographically heterogenous. Further surveys of patients presenting with acute fever are required to determine the contribution of these emerging viruses to febrile illness in Uganda.
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Anticuerpos Antivirales , Rhabdoviridae , Humanos , Uganda/epidemiología , Adulto , Masculino , Femenino , Adolescente , Adulto Joven , Persona de Mediana Edad , Anticuerpos Antivirales/sangre , Niño , Rhabdoviridae/aislamiento & purificación , Rhabdoviridae/genética , Rhabdoviridae/clasificación , Preescolar , Infecciones por Rhabdoviridae/epidemiología , Infecciones por Rhabdoviridae/virología , Infecciones por Rhabdoviridae/veterinaria , Estudios Seroepidemiológicos , Animales , Reacciones Cruzadas , Lactante , Anciano , Filogenia , Ensayo de Inmunoadsorción Enzimática , MetagenómicaRESUMEN
BACKGROUND: Hainan Island and the Leizhou Peninsula, the southernmost part of mainland China, are areas where Aedes aegypti and Ae. albopictus are sympatric and are also high-incidence areas of dengue outbreaks in China. Many studies have suggested that Aedes endogenous viral components (EVEs) are enriched in piRNA clusters which can silence incoming viral genomes. Investigation the EVEs present in the piRNA clusters associated with viral infection of Aedes mosquitoes in these regions may provide a theoretical basis for novel transmission-blocking vector control strategies. METHODS: In this study, specific primers for endogenous Flaviviridae elements (EFVEs) and endogenous Rhabdoviridae elements (ERVEs) were used to detect the distribution of Zika virus infection associated EVEs in the genomes of individuals of the two Aedes mosquitoes. Genetic diversity of EVEs with a high detection rate was also analyzed. RESULTS: The results showed that many EVEs associated with Zika virus infection were detected in both Aedes species, with the detection rates were 47.68% to 100% in Ae. aegypti and 36.15% to 92.31% in sympatric Ae. albopictus populations. EVEs detection rates in another 17 Ae. albopictus populations ranged from 29.39% to 89.85%. Genetic diversity analyses of the four EVEs (AaFlavi53, AaRha61, AaRha91 and AaRha100) of Ae. aegypti showed that each had high haplotype diversity and low nucleotide diversity. The number of haplotypes in AaFlavi53 was 8, with the dominant haplotype being Hap_1 and the other 7 haplotypes being further mutated from Hap_1 in a lineage direction. In contrast, the haplotype diversity of the other three ERVEs (AaRha61, AaRha91 and AaRha100) was more diverse and richer, with the haplotype numbers were 9, 15 and 19 respectively. In addition, these EVEs all showed inconsistent patterns of both population differentiation and dispersal compared to neutral evolutionary genes such as the Mitochondrial COI gene. CONCLUSION: The EFVEs and ERVEs tested were present at high frequencies in the field Aedes mosquito populations. The haplotype diversity of the EFVE AaFlavi53 was relatively lower and the three ERVEs (AaRha61, AaRha91, AaRha100) were higher. None of the four EVEs could be indicative of the genetic diversity of the Ae. aegypti population. This study provided theoretical support for the use of EVEs to block arbovirus transmission, but further research is needed into the mechanisms by which these EVEs are antiviral to Aedes mosquitoes.
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Aedes , Variación Genética , Rhabdoviridae , Aedes/virología , Aedes/genética , Animales , China/epidemiología , Rhabdoviridae/genética , Flaviviridae/genética , Flaviviridae/clasificación , Mosquitos Vectores/virología , Mosquitos Vectores/genética , Filogenia , ARN Interferente Pequeño/genética , Virus Zika/genética , Infección por el Virus Zika/virología , Infección por el Virus Zika/transmisión , Infección por el Virus Zika/epidemiologíaRESUMEN
The immune system of bony fish closely resembles that of mammals, comprising both specific (adaptive) and non-specific (innate) components. Notably, the mucosa-associated lymphoid tissue (MALT) serves as the first line of defense within the non-specific immune system, playing a critical role in protecting these aquatic organisms against invading pathogens. MALT encompasses a network of immune cells strategically distributed throughout the gills and intestines, forming an integral part of the mucosal barrier that interfaces directly with the surrounding aquatic environment. Spring Viremia of Carp Virusï¼SVCVï¼, a highly pathogenic agent causing substantial harm to common carp populations, has been designated as a Class 2 animal disease by the Ministry of Agriculture and Rural Affairs of China. Utilizing a comprehensive array of research techniques, including Hematoxylin and Eosin (HE)ãAlcian Blue Periodic Acid-Schiff (AB-PAS)ãtranscriptome analysis for global gene expression profiling and Reverse Transcription-Polymerase Chain Reaction (RT-qPCR), this study uncovered several key findings: SVCV is capable of compromising the mucosal architecture in the gill and intestinal tissues of carp, and stimulate the proliferation of mucous cells both in gill and intestinal tissues. Critically, the study revealed that SVCV's invasion elicits a robust response from the carp's mucosal immune system, demonstrating the organism's capacity to resist SVCV invasion despite the challenges posed by the pathogen.
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Carpas , Enfermedades de los Peces , Perfilación de la Expresión Génica , Branquias , Intestinos , Infecciones por Rhabdoviridae , Rhabdoviridae , Animales , Branquias/inmunología , Branquias/virología , Rhabdoviridae/fisiología , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/virología , Carpas/inmunología , Carpas/genética , Perfilación de la Expresión Génica/veterinaria , Infecciones por Rhabdoviridae/inmunología , Infecciones por Rhabdoviridae/veterinaria , Infecciones por Rhabdoviridae/virología , Intestinos/inmunología , Intestinos/virología , Inmunidad Innata/genética , Transcriptoma/inmunología , Inmunidad MucosaRESUMEN
Sequestosome 1 (SQSTM1/p62) is a selective autophagy adapter protein that participates in antiviral and bacterial immune responses and plays an important regulatory role in clearing the proteins to be degraded and maintaining intracellular protein homeostasis. In this study, two p62 genes were cloned from common carp (Cyprinus carpio), namely Ccp62-1 and Ccp62-2, and conducted bioinformatics analysis on them. The results showed that Ccp62s had the same structural domain (Phox and Bem1 domain, ZZ-type zinc finger domain, and ubiquitin-associated domain) as p62 from other species. Ccp62s were widely expressed in various tissues of fish, and highly expressed in immune organs such as gills, spleen, head kidney, etc. Subcellular localization study showed that they were mainly distributed in punctate aggregates in the cytoplasm. After stimulation with Aeromonas hydrophila and spring viraemia of carp virus (SVCV), the expression level of Ccp62s was generally up-regulated. Overexpression of Ccp62s in EPC cells could inhibit SVCV replication. Upon A. hydrophila challenge, the bacterial load in Ccp62s-overexpressing group was significantly reduced, the expression levels of pro-inflammatory cytokines and interferon factors were increased, and the survival rate of the fish was improved. These results indicated that Ccp62s were involved in the immune response of common carp to bacterial and viral infections.
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Aeromonas hydrophila , Carpas , Enfermedades de los Peces , Proteínas de Peces , Infecciones por Bacterias Gramnegativas , Inmunidad Innata , Filogenia , Infecciones por Rhabdoviridae , Rhabdoviridae , Animales , Carpas/inmunología , Carpas/genética , Enfermedades de los Peces/inmunología , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Aeromonas hydrophila/fisiología , Inmunidad Innata/genética , Rhabdoviridae/fisiología , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Rhabdoviridae/inmunología , Infecciones por Rhabdoviridae/veterinaria , Regulación de la Expresión Génica/inmunología , Proteína Sequestosoma-1/genética , Proteína Sequestosoma-1/inmunología , Perfilación de la Expresión Génica/veterinaria , Alineación de Secuencia/veterinaria , Secuencia de Aminoácidos , Autofagia/inmunologíaRESUMEN
Micropterus salmoides rhabdovirus (MSRV) is an important pathogen of largemouth bass. Despite extensive research, the functional receptors of MSRV remained unknown. This study identified the host protein, laminin receptor (LamR), as a cellular receptor facilitating MSRV entry into host cells. Our results demonstrated that LamR directly interacts with MSRV G protein, playing a pivotal role in the attachment and internalization processes of MSRV. Knockdown of LamR with siRNA, blocking cells with LamR antibody, or incubating MSRV virions with soluble LamR protein significantly reduced MSRV entry. Notably, we found that LamR mediated MSRV entry via clathrin-mediated endocytosis. Additionally, our findings revealed that MSRV G and LamR were internalized into cells and co-localized in the early and late endosomes. These findings highlight the significance of LamR as a cellular receptor facilitating MSRV binding and entry into target cells through interaction with the MSRV G protein. IMPORTANCE: Despite the serious epidemic caused by Micropterus salmoides rhabdovirus (MSRV) in largemouth bass, the precise mechanism by which it invades host cells remains unclear. Here, we determined that laminin receptor (LamR) is a novel target of MSRV, that interacts with its G protein and is involved in viral attachment and internalization, transporting with MSRV together in early and late endosomes. This is the first report demonstrating that LamR is a cellular receptor in the MSRV life cycle, thus contributing new insights into host-pathogen interactions.
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Enfermedades de los Peces , Receptores de Laminina , Rhabdoviridae , Internalización del Virus , Animales , Receptores de Laminina/metabolismo , Rhabdoviridae/metabolismo , Rhabdoviridae/fisiología , Enfermedades de los Peces/virología , Enfermedades de los Peces/metabolismo , Lubina/virología , Lubina/metabolismo , Receptores Virales/metabolismo , Infecciones por Rhabdoviridae/virología , Infecciones por Rhabdoviridae/metabolismo , EndocitosisRESUMEN
Potassium (K+) plays crucial roles in both plant development and immunity. However, the function of K+ in plant-virus interactions remains largely unknown. Here, we utilized Barley yellow striate mosaic virus (BYSMV), an insect-transmitted plant cytorhabdovirus, to investigate the interplay between viral infection and plant K+ homeostasis. The BYSMV accessory P9 protein exhibits viroporin activity by enhancing membrane permeability in Escherichia coli. Additionally, P9 increases K+ uptake in yeast (Saccharomyces cerevisiae) cells, which is disrupted by a point mutation of glycine 14 to threonine (P9G14T). Furthermore, BYSMV P9 forms oligomers and targets to both the viral envelope and the plant membrane. Based on the recombinant BYSMV-GFP (BYGFP) virus, a P9-deleted mutant (BYGFPΔP9) was rescued and demonstrated infectivity within individual plant cells of Nicotiana benthamiana and insect vectors. However, BYGFPΔP9 failed to infect barley plants after transmission by insect vectors. Furthermore, infection of barley plants was severely impaired for BYGFP-P9G14T lacking P9 K+ channel activity. In vitro assays demonstrate that K+ facilitates virion disassembly and the release of genome RNA for viral mRNA transcription. Altogether, our results show that the K+ channel activity of viroporins is conserved in plant cytorhabdoviruses and plays crucial roles in insect-mediated virus transmission.
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Hordeum , Nicotiana , Enfermedades de las Plantas , Rhabdoviridae , Hordeum/virología , Hordeum/genética , Enfermedades de las Plantas/virología , Rhabdoviridae/fisiología , Rhabdoviridae/genética , Animales , Nicotiana/virología , Nicotiana/genética , Potasio/metabolismo , Proteínas Virales/metabolismo , Proteínas Virales/genética , Insectos Vectores/virología , Virus de Plantas/fisiología , Virus de Plantas/patogenicidad , Virus de Plantas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/virologíaRESUMEN
Stimulator of interferon genes (STING), as an imperative adaptor protein in innate immune, responds to nucleic acid from invading pathogens to build antiviral responses in host cells. Aberrant activation of STING may trigger tissue damage and autoimmune diseases. Given the decisive role in initiating innate immune response, the activity of STING is intricately governed by several posttranslational modifications, including phosphorylation and ubiquitination. Here, we cloned and characterized a novel RNF122 homolog from common carp (named CcRNF122L). Expression analysis disclosed that the expression of CcRNF122L is up-regulated under spring viremia of carp virus (SVCV) stimulation in vivo and in vitro. Overexpression of CcRNF122L hampers SVCV- or poly(I:C)-mediated the expression of IFN-1 and ISGs in a dose-dependent way. Mechanistically, CcRNF122L interacts with STING and promotes the polyubiquitylation of STING. This polyubiquitylation event inhibits the aggregation of STING and the subsequent recruitment of TBK1 and IRF3 to the signaling complex. Additionally, the deletion of the TM domain abolishes the negative regulatory function of CcRNF122L. Collectively, our discoveries unveil a mechanism that governs the STING function and the precise adjustment of the innate immune response in teleost.
Asunto(s)
Carpas , Proteínas de Peces , Inmunidad Innata , Proteínas de la Membrana , Rhabdoviridae , Animales , Carpas/inmunología , Carpas/genética , Carpas/virología , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Rhabdoviridae/fisiología , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Proteínas de Peces/metabolismo , Ubiquitinación , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/virología , Infecciones por Rhabdoviridae/inmunología , Transducción de SeñalRESUMEN
Tripartite motif (TRIM) proteins are involved in different cellular functions, including regulating virus infection. In teleosts, two orthologous genes of mammalian TRIM2 are identified. However, the functions and molecular mechanisms of piscine TRIM2 remain unclear. Here, we show that trim2b-knockout zebrafish are more susceptible to spring viremia of carp virus (SVCV) infection than wild-type zebrafish. Transcriptomic analysis demonstrates that NOD-like receptor (NLR), but not RIG-I-like receptor (RLR), signaling pathway is significantly enriched in the trim2b-knockout zebrafish. In vitro, overexpression of Trim2b fails to degrade RLRs and those key proteins involved in the RLR signaling pathway but does for negative regulators NLRP12-like proteins. Zebrafish Trim2b degrades NLRP12-like proteins through its NHL_TRIM2_like and IG_FLMN domains in a ubiquitin-proteasome degradation pathway. SVCV-N and SVCV-G proteins are also degraded by NHL_TRIM2_like domains, and the degradation pathway is an autophagy lysosomal pathway. Moreover, zebrafish Trim2b can interfere with the binding between NLRP12-like protein and SVCV viral RNA and can completely block the negative regulation of NLRP12-like protein on SVCV infection. Taken together, our data demonstrate that the mechanism of action of zebrafish trim2b against SVCV infection is through targeting the degradation of host-negative regulators NLRP12-like receptors and viral SVCV-N/SVCV-G genes.IMPORTANCESpring viremia of carp virus (SVCV) is a lethal freshwater pathogen that causes high mortality in cyprinid fish. In the present study, we identified zebrafish trim2b, NLRP12-L1, and NLRP12-L2 as potential pattern recognition receptors (PRRs) for sensing and binding viral RNA. Zebrafish trim2b functions as a positive regulator; however, NLRP12-L1 and NLRP12-L2 function as negative regulators during SVCV infection. Furthermore, we find that zebrafish trim2b decreases host lethality in two manners. First, zebrafish Trim2b promotes protein degradations of negative regulators NLRP12-L1 and NLRP12-L2 by enhancing K48-linked ubiquitination and decreasing K63-linked ubiquitination. Second, zebrafish trim2b targets viral RNAs for degradation. Therefore, this study reveals a special antiviral mechanism in lower vertebrates.
Asunto(s)
Carpas , Proteolisis , Receptores de Reconocimiento de Patrones , Rhabdoviridae , Proteínas de Motivos Tripartitos , Proteínas Virales , Proteínas de Pez Cebra , Pez Cebra , Animales , Carpas/virología , Proteína 58 DEAD Box/metabolismo , Enfermedades de los Peces/virología , Enfermedades de los Peces/metabolismo , Inmunidad Innata , Receptores de Reconocimiento de Patrones/metabolismo , Rhabdoviridae/metabolismo , Infecciones por Rhabdoviridae/metabolismo , Infecciones por Rhabdoviridae/veterinaria , Infecciones por Rhabdoviridae/virología , Transducción de Señal , Proteínas de Motivos Tripartitos/deficiencia , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitinación , Proteínas Virales/metabolismo , Viremia/veterinaria , Viremia/virología , Pez Cebra/genética , Pez Cebra/metabolismo , Pez Cebra/virología , Proteínas de Pez Cebra/deficiencia , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismoRESUMEN
USP14 regulates the immune related pathways by deubiquitinating the signaling molecules in mammals. In teleost, USP14 is also reported to inhibit the antiviral immune response through TBK1, but its regulatory mechanism remains obscure. To elucidate the role of USP14 in the RLR/IFN antiviral pathway in teleost, the homolog USP14 (bcUSP14) of black carp (Mylopharyngodon piceus) has been cloned and characterize in this paper. bcUSP14 contains 490 amino acids (aa), and the sequence is well conserved among in vertebrates. Over-expression of bcUSP14 in EPC cells attenuated SVCV-induced transcription activity of IFN promoters and enhanced SVCV replication. Knockdown of bcUSP14 in MPK cells led to the increased transcription of IFNs and decreased SVCV replication, suggesting the improved antiviral activity of the host cells. The interaction between bcUSP14 and bcTBK1 was identified by both co-immunoprecipitation and immunofluorescent staining. Co-expressed bcUSP14 obviously inhibited bcTBK1-induced IFN production and antiviral activity in EPC cells. K63-linked polyubiquitination of bcTBK1 was dampened by co-expressed bcUSP14, and bcTBK1-mediated phosphorylation and nuclear translocation of IRF3 were also inhibited by this deubiquitinase. Thus, all the data demonstrated that USP14 interacts with and inhibits TBK1 through deubiquitinating TBK1 in black carp.