Unveiling the Virome of Wild Birds: Exploring CRESS-DNA Viral Dark Matter.

Amid global health concerns and the constant threat of zoonotic diseases, this study delves into the diversity of circular replicase-encoding single-stranded DNA (CRESS-DNA) viruses within Chinese wild bird populations. Employing viral metagenomics to tackle the challenge of "viral dark matter, " the research collected and analyzed 3,404 cloacal swab specimens across 26 bird families. Metagenomic analysis uncovered a rich viral landscape, with 67.48% of reads classified as viral dark matter, spanning multiple taxonomic levels. Notably, certain viral families exhibited host-specific abundance patterns, with Galliformes displaying the highest diversity. Diversity analysis categorized samples into distinct groups, revealing significant differences in viral community structure, particularly noting higher diversity in terrestrial birds compared to songbirds and unique diversity in migratory birds versus perching birds. The identification of ten novel Circoviridae viruses, seven Smacoviridae viruses, and 167 Genomoviridae viruses, along with 100 unclassified CRESS-DNA viruses, underscores the expansion of knowledge on avian-associated circular DNA viruses. Phylogenetic and structural analyses of Rep proteins offered insights into evolutionary relationships and potential functional variations among CRESS-DNA viruses. In conclusion, this study significantly enhances our understanding of the avian virome, shedding light on the intricate relationships between viral communities and host characteristics in Chinese wild bird populations. The diverse array of CRESS-DNA viruses discovered opens avenues for future research into viral evolution, spread factors, and potential ecosystem impacts.

Metagenomic analysis reveals high diversity of gut viromes in yaks (Bos grunniens) from the Qinghai-Tibet Plateau.

The Qinghai-Tibet Plateau (QTP), renowned for its exceptional biological diversity, is home to numerous endemic species. However, research on the virology of vulnerable vertebrates like yaks remains limited. In this study, our objective was to use metagenomics to provide a comprehensive understanding of the diversity and evolution of the gut virome in yak populations across different regions of the QTP. Our findings revealed a remarkably diverse array of viruses in the gut of yaks, including those associated with vertebrates and bacteriophages. Notably, some vertebrate-associated viruses, such as astrovirus and picornavirus, showed significant sequence identity across diverse yak populations. Additionally, we observed differences in the functional profiles of genes carried by the yak gut virome across different regions. Moreover, the virus-bacterium symbiotic network that we discovered holds potential significance in maintaining the health of yaks. Overall, this research expands our understanding of the viral communities in the gut of yaks and highlights the importance of further investigating the interactions between viruses and their hosts. These data will be beneficial for revealing the crucial role that viruses play in the yak gut ecology in future studies.

Highly diverse RNA viruses and phage sequences concealed within birds.

The diversity of birds in most parts of the world is very high, and thus, they may carry different types of highly differentiated and unknown viruses. Thanks to advanced sequencing technologies, studies on the diversity of bird-associated viruses have increased over the past few years. In this study, a large-scale viral metagenomics survey was performed on cloacal swabs of 2,990 birds from nine provinces of the Chinese mainland. To detect undescribed RNA viruses in birds, more than 1,800 sequences sharing relatively low (<60%) amino acid sequence identity with the best match in the GenBank database were screened. Potentially novel viruses related to vertebrates have been identified, and several potential recombination signals were found. Additionally, hundreds of RNA viral sequences related to plants, fungi, and insects were detected, including previously unknown viruses. Furthermore, we investigated the novelty, functionality, and classification of the phages examined in this study. These viruses occupied topological positions on the evolutionary trees to a certain extent and might form novel putative families, genera, or species, thus providing information to fill the phylogenetic gaps of related viruses. These findings provided new insights into bird-associated viruses, but the interactions among these viruses remain unknown and require further investigation.IMPORTANCEStudying the diversity of RNA viruses in birds and mammals is crucial due to their potential impact on human health and the global ecosystem. Many RNA viruses, such as influenza and coronaviruses, have been shown to cross the species barrier and cause zoonotic diseases. In this metagenomics study involving 2,990 birds from at least 82 species, we identified over 1,800 RNA sequences with distant relationships to known viruses, some of which are rare in birds. The study highlights the scope and diversity of RNA viruses in birds, providing data to predict disease risks and monitor potential viral threats to wildlife, livestock, and human health. This information can aid in the development of strategies for disease prevention and control.

Development of a label-free photoelectrochemical immunosensor for novel astrovirus detection.

Since 2017, an infectious goose gout disease characterized by urate precipitation in viscera, mainly caused by novel goose astrovirus (GoAstV) infection, has emerged in the main goose-producing region of China. The current challenge in managing goose gout disease is largely due to the absence of a rapid and efficient detection method for the GoAstV pathogen. Notably, the potential application of immunosensors in detecting GoAstV has not yet been explored. Herein, a label-free PEC immunosensor was fabricated by using purchased TiO2 as the photoactive material and antibody against GoAstV P2 proteins as the specific recognition element. First, we successfully expressed the capsid spike domain P2 protein of ORF2 from GoAstV CHSH01 by using the pET prokaryotic expression system. Meanwhile, the polyclonal antibody against GoAstV capsid P2 protein was produced by purified protein. To our knowledge, this is the first establishment and preliminary application of the label-free photoelectrochemical immunosensor method in the detection of AstV. The PEC immunosensor had a linear range of 1.83 fg mL-1 to 3.02 ng mL-1, and the limit of detection (LOD) was as low as 0.61 fg mL-1. This immunosensor exhibited high sensitivity, great specificity, and good stability in detecting GoAstV P2 proteins. To evaluate the practical application of the immunosensor in real-world sample detection, allantoic fluid from goose embryos was collected as test samples. The results indicated that of the eight positive samples, one false negative result was detected, while both negative samples were accurately detected, suggesting that the constructed PEC immunosensor had good applicability and practical application value, providing a platform for the qualitative detection of GoAstV.

Pangenome and multi-tissue gene atlas provide new insights into the domestication and highland adaptation of yaks.

BACKGROUND: The genetic diversity of yak, a key domestic animal on the Qinghai-Tibetan Plateau (QTP), is a vital resource for domestication and breeding efforts. This study presents the first yak pangenome obtained through the de novo assembly of 16 yak genomes. RESULTS: We discovered 290 Mb of nonreference sequences and 504 new genes. Our pangenome-wide presence and absence variation (PAV) analysis revealed 5,120 PAV-related genes, highlighting a wide range of variety-specific genes and genes with varying frequencies across yak populations. Principal component analysis (PCA) based on binary gene PAV data classified yaks into three new groups: wild, domestic, and Jinchuan. Moreover, we proposed a 'two-haplotype genomic hybridization model' for understanding the hybridization patterns among breeds by integrating gene frequency, heterozygosity, and gene PAV data. A gene PAV-GWAS identified a novel gene (BosGru3G009179) that may be associated with the multirib trait in Jinchuan yaks. Furthermore, an integrated transcriptome and pangenome analysis highlighted the significant differences in the expression of core genes and the mutational burden of differentially expressed genes between yaks from high and low altitudes. Transcriptome analysis across multiple species revealed that yaks have the most unique differentially expressed mRNAs and lncRNAs (between high- and low-altitude regions), especially in the heart and lungs, when comparing high- and low-altitude adaptations. CONCLUSIONS: The yak pangenome offers a comprehensive resource and new insights for functional genomic studies, supporting future biological research and breeding strategies.

Viral metagenomic analysis reveals diverse viruses and a novel bocaparvovirus in the enteric virome of snow leopard (Panthera uncia).

The enteric virome, comprising a complex community of viruses inhabiting the gastrointestinal tract, plays a significant role in health and disease dynamics. In this study, the fecal sample of a wild snow leopard was subjected to viral metagenomic analysis using a double barcode Illumina MiSeq platform. The resulting reads were de novo assembled into contigs with SOAPdenovo2 version r240. Additional bioinformatic analysis of the assembled genome and genome annotation was done using the Geneious prime software (version 2022.0.2). Following viral metagenomic analysis and bioinformatic analysis, a total of 7 viral families and a novel specie of bocaparvovirus tentatively named Panthera uncia bocaparvovirus (PuBOV) with GenBank accession number OQ627713 were identified. The complete genome of PuBOV was predicted to contain 3 open reading frames (ORFs), contains 5433 nucleotides and has a G + C content of 47.40 %. BLASTx analysis and pairwise sequence comparison indicated the novel virus genome was a new species in the genus Bocaparvovirus based on the species demarcation criteria of the International Committee on the Taxonomy of Viruses. This study provides valuable insights into the diversity and composition of the enteric virome in wild endangered snow leopards. The identification and characterization of viruses in wildlife is crucial for developing effective strategies to manage and mitigate potential zoonotic and other viral disease threats to human and animal health.

Corrigendum: A metagenomic analysis of mosquito virome collected from different animal farms at Yunnan-Myanmar border of China.

[This corrects the article DOI: 10.3389/fmicb.2020.591478.].

RBM14 inhibits the replication of porcine epidemic diarrhea virus by recruiting p62 to degrade nucleocapsid protein through the activation of autophagy and interferon pathway.

Porcine epidemic diarrhea virus (PEDV) results in PED, which is an infectious intestinal disease with the representative features of diarrhea, vomiting, and dehydration. PEDV infects neonatal piglets, causing high mortality rates. Therefore, elucidating the interaction between the virus and host in preventing and controlling PEDV infection is of immense significance. We found a new antiviral function of the host protein, RNA-binding motif protein 14 (RBM14), which can inhibit PEDV replication via the activation of autophagy and interferon (IFN) signal pathways. We found that RBM14 can recruit cargo receptor p62 to degrade PEDV nucleocapsid (N) protein through the RBM14-p62-autophagosome pathway. Furthermore, RBM14 can also improve the antiviral ability of the hosts through interacting with mitochondrial antiviral signaling protein to induce IFN expression. These results highlight the novel mechanism underlying RBM14-induced viral restriction. This mechanism leads to the degradation of viral N protein via the autophagy pathway and upregulates IFN for inhibiting PEDV replication; thus, offering new ways for preventing and controlling PED.IMPORTANCEPorcine epidemic diarrhea virus (PEDV) is a vital reason for diarrhea in neonatal piglets, which causes high morbidity and mortality rates. There is currently no effective vaccine or drug to treat and prevent infection with the PEDV. During virus infection, the host inhibits virus replication through various antiviral factors, and at the same time, the virus antagonizes the host's antiviral reaction through its own encoded protein, thus completing the process of virus replication. Our study has revealed that the expression of RNA-binding motif protein 14 (RBM14) was downregulated in PEDV infection. We found that RBM14 can recruit cargo receptor p62 to degrade PEDV N protein via the RBM14-p62-autophagosome pathway and interacted with mitochondrial antiviral signaling protein and TRAF3 to activate the interferon signal pathway, resulting in the inhibition of PEDV replication.

An Expeditious Neutralization Assay for Porcine Reproductive and Respiratory Syndrome Virus Based on a Recombinant Virus Expressing Green Fluorescent Protein.

Due to the extensive genetic and antigenic variation in Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), as well as its rapid mutability and evolution, PRRS prevention and control can be challenging. An expeditious and sensitive neutralization assay for PRRSV is presented to monitor neutralizing antibodies (NAbs) in serum during vaccine research. Here, a PRRSV expressing eGFP was successfully rescued with reverse genetics based on the infectious clone HuN4-F112-eGFP which we constructed. The fluorescent protein expressions of the reporter viruses remained stable for at least five passages. Based on this reporter virus, the neutralization assay can be easily used to evaluate the level of NAbs by counting cells with green fluorescence. Compared with the classical CPE assay, the newly developed assay increases sensitivity by one- to four-fold at the early antibody response stage, thus saving 2 days of assay waiting time. By using this assay to unveil the dynamics of neutralizing antibodies against PRRSV, priming immunity through either a single virulent challenge or only vaccination could produce limited NAbs, but re-infection with PRRSV would induce a faster and stronger NAb response. Overall, the novel HuN4-F112-eGFP-based neutralization assay holds the potential to provide a highly efficient platform for evaluating the next generation of PRRS vaccines.

Metagenomic survey of viral diversity obtained from feces of piglets with diarrhea.

Pigs are natural host to various zoonotic pathogens including viruses. In this study, we analyzed the viral communities in the feces of 89 piglets with diarrhea under one month old which were collected from six farms in Jiangsu Province of the Eastern China, using the unbiased virus metagenomic method. A total of 89 libraries were constructed, and 46937894 unique sequence reads were generated by Illumina sequencing. Overall, the family Picornaviridae accounted for the majority of the total reads of putative mammalian viruses. Ten novel virus genomes from different family members were discovered, including Parvoviridae (n = 2), Picobirnaviridae (n = 4) and CRESS DNA viruses (n = 4). A large number of phages were identified, which mainly belonged to the order Caudovirales and the family Microviridae. Moreover, some identified viruses were closely related to viruses found in non-porcine hosts, highlighting the potential for cross-species virus dissemination. This study increased our understanding of the fecal virus communities of diarrhea piglets and provided valuable information for virus monitoring and preventing.

Identification of Linear Epitopes in the C-Terminal Region of ASFV p72 Protein.

African swine fever, which is induced by the African swine fever virus (ASFV), poses a significant threat to the global pig industry due to its high lethality in domestic pigs and wild boars. Despite the severity of the disease, there is a lack of effective vaccines and drugs against the ASFV. The p72 protein, constituting 31 to 33% of the total virus particle mass, serves as the primary capsid protein of ASFV. It is a crucial antigen for the development of ASF subunit vaccines and serological diagnostic methods. In this investigation, 27 monoclonal antibodies (mAbs) were generated through mouse immunization with the truncated C-terminal p72 protein expressed by Escherichia coli. Among these, six mAbs exhibited binding to the p72 trimer, with their respective recognized epitopes identified as 542VTAHGINLIDKF553, 568GNAIKTP574, and 584FALKPREEY592. All three epitopes were situated within the interval sequences of functional units of the C-terminal jelly-roll barrel of p72. Notably, two epitopes, 568GNAIKTP574 and 584FALKPREEY592, were internal to the p72 trimer, while the epitope 542VTAHGINLIDKF553 was exposed on the surface of the trimer and consistently conserved across all ASFV genotypes. These findings enhance our comprehension of the antigenic function and structure of the p72 protein, facilitating the utilization of p72 in the development of diagnostic techniques for ASFV.

PGAM5 degrades PDCoV N protein and activates type I interferon to antagonize viral replication.

IMPORTANCE: As a member of the δ-coronavirus family, porcine deltacoronavirus (PDCoV) is a vital reason for diarrhea in piglets, which can contribute to high morbidity and mortality rates. Initially identified in Hong Kong in 2012, the virus has rapidly spread worldwide. During PDCoV infection, the virus employs evasion mechanisms to evade host surveillance, while the host mounts corresponding responses to impede viral replication. Our research has revealed that PDCoV infection down-regulates the expression of PGAM5 to promote virus replication. In contrast, PGAM5 degrades PDCoV N through autophagy by interacting with the cargo receptor P62 and the E3 ubiquitination ligase STUB1. Additionally, PGAM5 interacts with MyD88 and TRAF3 to activate the IFN signal pathway, resulting in the inhibition of viral replication.

Virome of high-altitude canine digestive tract and genetic characterization of novel viruses potentially threatening human health.

The majority of currently emerging infectious illnesses are zoonotic infections, which have caused serious public health and economic implications. The development of viral metagenomics has helped us to explore unknown viruses. We collected 1,970 canine feces from Yushu and Guoluo in the plateau region of China for this study to do a metagenomics analysis of the viral community of the canine digestive tract. Our analysis identified 203 novel viruses, classified into 11 known families and 2 unclassified groups. These viruses include the hepatitis E virus, first identified in dogs, and the astrovirus, coronavirus, polyomavirus, and others. The relationship between the newly identified canine viruses and known viruses was investigated through the use of phylogenetic analysis. Furthermore, we demonstrated the cross-species transmission of viruses and predicted new viruses that may cause diseases in both humans and animals, providing technical support for the prevention and control of diseases caused by environmental pollution viruses. IMPORTANCE Most emerging infectious diseases are due to zoonotic disease agents. Because of their effects on the security of human or animal life, agriculture production, and food safety, zoonotic illnesses and livestock diseases are of worldwide significance. Because dogs are closely related to humans and domestic animals, they serve as one of the important links in the transmission of zoonotic and livestock diseases. Canines can contaminate the environment in which humans live such as water and soil through secretions, potentially altering the human gut microbiota or causing diseases. Our study enriched the viral community in the digestive tract microbiome of dogs and found types of viruses that threaten human health, providing technical support for the prevention and control of early warning of diseases caused by environmental contaminant viruses.

Metagenomic analysis of herbivorous mammalian viral communities in the Northwest Plateau.

BACKGROUND: Mammals are potential hosts for many infectious diseases. However, studies on the viral communities of herbivorous mammals in the Northwest Plateau are limited. Here, we studied the viral communities of herbivorous mammals in the Northwest Plateau using virus metagenomic analysis to analyze and compare the viral community composition of seven animal species. RESULTS: By library construction and next-generation sequencing, contigs and singlets reads with similar viral sequences were classified into 24 viral families. Analyzed from the perspective of sampling areas, the virus community composition was relatively similar in two areas of Wuwei and Jinchang, Gansu Province. Analyzed from the perspective of seven animal species, the viral reads of seven animal species were mostly ssDNA and dominated by CRESS-DNA viruses. Phylogenetic analysis based on viral marker genes indicated that CRESS-DNA viruses and microviruses have high genetic diversity. In addition to DNA viruses, nodaviruses, pepper mild mottle viruses and picornaviruses were RNA viruses that we performed by phylogenetic analysis. The CRESS-DNA viruses and nodaviruses are believed to infect plants and insects, and microviruses can infect bacteria, identifying that they were likely from the diet of herbivorous mammals. Notably, two picornaviruses were identified from red deer and wild horse, showing that the picornavirus found in red deer had the relatively high similarity with human hepatitis A virus, and the picornavirus carried by wild horse could potentially form a new species within the Picornaviridae family. CONCLUSIONS: This study explored the herbivorous mammalian virus community in the Northwest Plateau and the genetic characteristics of viruses that potentially threaten human health. It reveals the diversity and stability of herbivorous mammalian virus communities in the Northwest Plateau and helps to expand our knowledge of various herbivorous mammalian potentially pathogenic viruses.

PEDV N protein capture protein translation element PABPC1 and eIF4F to promote viral replication.

Porcine epidemic diarrhea (PED) is an acute, highly infectious intestinal disease caused by the porcine epidemic diarrhea virus (PEDV), which seriously endangers the healthy development of the pig industry. PEDV N protein is the most abundant viral structural protein, which can be combined with viral genomic RNA to form ribonucleoprotein complexes, thereby participating in the transcription and replication of the virus. However, how PEDV hijacks the host transcription translation system to promote viral proliferation remains unclear. In this study, we found that there is an interaction between PEDV N, polyadenylate-binding protein cytoplasmic 1 (PABPC1) and eukaryotic initiation factor 4F (eIF4F) proteins through coimmunoprecipitation, GST pulldown and fluorescence microscopy experiments. PABPC1 could bind to the poly(A) tail of the mRNA, and eIF4F could bind to the 5' end cap structure of the mRNA, so the interaction of PABPC1 and eIF4F could facilitate mRNA forming a circular shape to promote translation to the proteins. To further explore the effect of N protein capture protein translation element PABPC1 and eIF4F on PEDV replication, we overexpressed PABPC1, eIF4F (containing eIF4A, eIF4E and eIF4G) separately on Vero cells and LLC-PK1 cells, and we found that the PABPC1 and eIF4F protein could promote PEDV replication. Taken together, our data suggested that PEDV N protein promoted cyclization of viral mRNA carried by N protein through binding with PABPC1 and eIF4F proteins, thus promoting viral transcription and facilitating viral replication.

PTBP1 suppresses porcine epidemic diarrhea virus replication via inducing protein degradation and IFN production.

Porcine epidemic diarrhea virus (PEDV) causes severe morbidity and mortality among newborn piglets. It significantly threatens the porcine industry in China and around the globe. To accelerate the developmental pace of drugs or vaccines against PEDV, a deeper understanding of the interaction between viral proteins and host factors is crucial. The RNA-binding protein, polypyrimidine tract-binding protein 1 (PTBP1), is crucial for controlling RNA metabolism and biological processes. The present work focused on exploring the effect of PTBP1 on PEDV replication. PTBP1 was upregulated during PEDV infection. The PEDV nucleocapsid (N) protein was degraded through the autophagic and proteasomal degradation pathways. Moreover, PTBP1 recruits MARCH8 (an E3 ubiquitin ligase) and NDP52 (a cargo receptor) for N protein catalysis and degradation through selective autophagy. Furthermore, PTBP1 induces the host innate antiviral response via upregulating the expression of MyD88, which then regulates TNF receptor-associated factor 3/ TNF receptor-associated factor 6 expression and induces the phosphorylation of TBK1 and IFN regulatory factor 3. These processes activate the type Ⅰ IFN signaling pathway to antagonize PEDV replication. Collectively, this work illustrates a new mechanism related to PTBP1-induced viral restriction, where PTBP1 degrades the viral N protein and induces type Ⅰ IFN production to suppress PEDV replication.

Gut phageome of the giant panda (Ailuropoda melanoleuca) reveals greater diversity than relative species.

The gut flora is a treasure house of diverse bacteriophages maintaining a harmonious and coexistent relationship with their hosts. The giant panda (Ailuropoda melanoleuca), as a vulnerable endemic species in China, has existed for millions of years and is regarded as a flagship species for biodiversity conservation. And yet, limited studies have analyzed the phage communities in the gut of giant pandas. Using viral metagenomic analysis, the phageomes of giant pandas and other relative species were investigated. Our study explored and compared the composition of phage communities from different animal sources. Giant pandas possessed more diverse and abundant phage communities in the gut compared with other relevant animals. Phylogenetic analyses based on the phage terminase large subunit (TerL) showed that the Caudovirales phages in giant pandas also presented highly genetic diversity. Our study revealed the diversity of phage communities in giant pandas and other relative species, contributing to the health maintenance of giant pandas and laying the groundwork for molecular evolution research of bacteriophages in mammals. IMPORTANCE Gut phageome plays an important role in shaping gut microbiomes by direct interactions with bacteria or indirect influences on the host immune system, potentially regulating host health and disease status. The giant panda (Ailuropoda melanoleuca) is a vulnerable and umbrella species for biodiversity conservation. Our work explored and compared the gut phageome of giant pandas and relative species, contributing to the health maintenance of giant pandas.

Comparison of viral communities in the blood, feces and various tissues of wild brown rats (Rattus norvegicus).

Viral diseases caused by new outbreaks of viral infections pose a serious threat to human health. Wild brown rats (Rattus norvegicus), considered one of the world's largest and most widely distributed rodents, are host to various zoonotic pathogens. To further understand the composition of the virus community in wild brown rats and explore new types of potentially pathogenic viruses, viral metagenomics was conducted to investigate blood, feces, and various tissues of wild brown rats captured from Zhenjiang, China. Results indicated that the composition of the virus community in different samples showed significant differences. In blood and tissue samples, members of the Parvoviridae and Anelloviridae form the main body of the virus community. Picornaviridae, Picobirnaviridae, and Astroviridae made up a large proportion of fecal samples. Several novel genome sequences from members of different families, including Anelloviridae, Parvoviridae, and CRESS DNA viruses, were detected in both blood and other samples, suggesting that they have the potential to spread across organs to cause viremia. These viruses included not only strains closely related to human viruses, but also a potential recombinant virus. Multiple dual-segment picornaviruses were obtained from fecal samples, as well as virus sequences from the Astroviridae and Picornaviridae. Phylogenetic analysis showed that these viruses belonged to different genera, with multiple viruses clustered with other animal viruses. Whether they have pathogenicity and the ability to spread across species needs further study.

Viromics Reveals the High Diversity of Viruses from Fishes of the Tibet Highland.

Aquaculture is important for food security and nutrition. The economy has recently been significantly threatened and the risk of zoonoses significantly increased by aquatic diseases, and the ongoing introduction of new aquatic pathogens, particularly viruses, continues to represent a hazard. Yet, our knowledge of the diversity and abundance of fish viruses is still limited. Here, we conducted a metagenomic survey of different species of healthy fishes caught in the Lhasa River, Tibet, China, and sampled intestinal contents, gills, and tissues. To be more precise, by identifying and analyzing viral genomes, we aim to determine the abundance, diversity, and evolutionary relationships of viruses in fish with other potential hosts. Our analysis identified 28 potentially novel viruses, 22 of which may be associated with vertebrates, across seven viral families. During our research, we found several new strains of viruses in fish, including papillomavirus, hepadnavirus, and hepevirus. Additionally, we discovered two viral families, Circoviridae and Parvoviridae, which were prevalent and closely related to viruses that infect mammals. These findings further expand our understanding of highland fish viruses and highlight the emerging view that fish harbor large, unknown viruses. IMPORTANCE The economy and zoonoses have recently been significantly threatened by aquatic diseases. Yet, our knowledge of the diversity and abundance of fish viruses is still limited. We identified the wide genetic diversity of viruses that these fish were harboring. Since there are currently few studies on the virome of fish living in the Tibet highland, our research adds to the body of knowledge. This discovery lays the groundwork for future studies on the virome of fish species and other highland animals, preserving the ecological equilibrium on the plateau.

Screening and identification of the dominant antigens of the African swine fever virus.

African swine fever is a highly lethal contagious disease of pigs for which there is no vaccine. Its causative agent African swine fever virus (ASFV) is a highly complex enveloped DNA virus encoding more than 150 open reading frames. The antigenicity of ASFV is still unclear at present. In this study, 35 proteins of ASFV were expressed by Escherichia coli, and ELISA was developed for the detection of antibodies against these proteins. p30, p54, and p22 were presented as the major antigens of ASFV, positively reacting with all five clinical ASFV-positive pig sera, and 10 pig sera experimentally infected by ASFV. Five proteins (pB475L, pC129R, pE199L, pE184L, and pK145R) reacted well with ASFV-positive sera. The p30 induced a rapid and strong antibody immune response during ASFV infection. These results will promote the development of subunit vaccines and serum diagnostic methods against ASFV.