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Picobirnaviruses encode proteins that are functional bacterial lysins.

Picobirnaviruses (PBVs) are double-stranded RNA viruses frequently detected in human and animal enteric viromes. Associations of PBVs with enteric graft-versus-host disease and type I diabetes during pregnancy have been established. Since their discovery in 1988, PBVs have been generally assumed to be animal-infecting viruses despite the lack of culture system, animal model, or detection in animal cells or tissues. Recent studies have proposed that bacteria or fungi could be the hosts of PBVs based on genomic analysis. Here, we functionally demonstrate that multiple PBVs of different genome or…

Extensive genome-wide variability of human cytomegalovirus in congenitally infected infants.

Research has shown that RNA virus populations are highly variable, most likely due to low fidelity replication of RNA genomes. It is generally assumed that populations of DNA viruses will be less complex and show reduced variability when compared to RNA viruses. Here, we describe the use of high throughput sequencing for a genome wide study of viral populations from urine samples of neonates with congenital human cytomegalovirus (HCMV) infections. We show that HCMV intrahost genomic variability, both at the nucleotide and amino acid level, is comparable to many RNA viruses, including HIV. With…

A comparison of La Crosse virus isolated obtained from different ecological niches and an analysis of the structural components of California encephalitis serogroup viruses and other bunyaviruses.

Analyses of the oligonucleotide fingerprints of the three genome ribonucleic acid (RNA) species of 11 isolates of La Crosse (LAC) virus, obtained from various ecological niches in the northern United States and compared to those of prototype LAC virus, showed that in each place from which these isolates were obtained LAC variants and varieties were present with related, but distinguishable, nucleotide sequences for their large, medium, or small RNA species. The RNA genomes of prototypes trivittatus (TVT), snowshoe hare (SSH), Tahyna (TAH), and Lumbo (a variety of TAH) viruses of the California

Metagenomic Analysis of the Jinding Duck Fecal Virome.

Ducks play an important role in transmitting and maintaining mammalian viruses in nature, and are a reservoir host of many animal viruses. We analyzed the fecal virome of four strains (A, B, C, and D) of ducks living in isolation by using metagenomic analysis. The feces of the ducks tested contained 18 animal virus families. The percentage values of RNA virus reads, compared to the total animal virus reads in each of the four strains were 96.96% (A), 97.30% (B), 98.01 (C), and 67.49% (D), and were mainly from Orthomyxoviridae, Mimiviridae, Bunyaviridae, Picobirnaviridae, and Reoviridae. Meanwh

The Antiviral Activity of Polyphenols.

Polyphenols are secondary metabolites produced by a large variety of plants. These compounds that comprise the class of phenolic acids, stil … e-stranded linear or partially double-stranded circular DNA viruses, negative sense single-stranded RNA viruses with nonsegmented or segmented genomes, and positive sense single-stranded RNA viruses). The present work emphasizes the relevance of polyphenols, in particular epigallocatechin-3-gallate and resveratrol, as alternative or supportive antivirals. Pol …

Comprehensive detection of viruses in pediatric patients with acute liver failure using next-generation sequencing.

BACKGROUND: Pediatric acute liver failure (PALF) is a rare and severe syndrome that frequently requires liver transplantation. Viruses are one of the most frequent causes of this disease, however, pathogenic viruses are not determined in many patients. Recently next-generation sequencing (NGS) has been applied to comprehensively detect pathogens of infectious diseases of unknown etiology. OBJECTIVES: To evaluate an NGS-based approach for detecting pathogenic viruses in patients with PALF or acute hepatitis of unknown etiology. STUDY DESIGN: To detect virus-derived DNA and RNA sequences exist

A pan-viral map of host dependency factors from multi-omics integration and machine learning across influenza A, SARS-CoV-2, Zika, and dengue viruses.

BACKGROUND: Host dependency factors (HDF) are essential for viral replication and are promising targets for broad-spectrum antivirals. However, most work has focused on individual viruses or individual data types, limiting our understanding of shared host mechanisms across viruses. METHODS: We developed a pan-viral framework that integrates multi-omics data-including genome-wide perturbation screens, single-cell transcriptomes and viral interactomes-and combines graph-based learning with classical machine-learning models to prioritize HDF for four RNA viruses (SARS-CoV-2, influenza A virus, d…

Reovirus-induced acute myocarditis in mice correlates with viral RNA synthesis rather than generation of infectious virus in cardiac myocytes.

The capacity for different reovirus reassortant viruses to induce acute myocarditis in mice correlates with cytopathogenic effect in primary cultures of murine cardiac myocytes. Multiple viral genes encoding proteins involved in viral RNA synthesis are determinants of this disease. We therefore evaluated the role of viral RNA synthesis in induction of acute myocarditis by infecting primary cultures of cardiac myocytes with a panel of myocarditic and nonmyocarditic viruses and quantitating RNA synthesis. RNA synthesis correlated with induction of myocarditis and with the S1 and M1 reovirus gene

Использование Волбачии для ликвидации Денге: будет ли вирус сражаться?

Недавние полевые испытания показали, что частотность денге может быть существенно снижена за счет интуиции штаммов эндосимбиотической бактерии Волбачии в популяции комаров Aedes aegypti. Эта стратегия основана на том, что Волбачия уменьшает уязвимость Ээгипти к распространению инфекции с помощью таких позитивных вирусов РНК, как денге. Однако хорошо известно, что вирусы РНК адаптируются к антивирусному давлению. Здесь мы проанализируем стадии вирусной инфекции, где может произойти выбор устойчивых к вирусу волбачи. Мы также рассматриваем генетические ограничения, налагаемые на вирусы, которые

Совпадение в аннотации оригинала
Recent field trials have demonstrated that dengue incidence can be substantially reduced by introgressing strains of the endosymbiotic bacterium Wolbachia into Aedes aegypti mosquito populations. This strategy relies on Wolbachia reducing the susceptibility of Ae. aegypti to disseminated infection by positive-sense RNA viruses like dengue. However, RNA virus…

Sequences of Previously Unknown Rhabdoviruses Detected in Bat Samples from the Republic of the Congo.

The family Rhabdoviridae contains diverse viruses, including vector-borne and nonvector-borne viruses, some that are human pathogens, including rabies virus and also nonpathogenic viruses. Bats, which are a known reservoir of viruses with zoonotic potential including coronaviruses, also carry multiple rhabdoviruses such as but not limited to lyssaviruses. We collected samples from 193 insectivorous and frugivorous bats in the Republic of the Congo and tested them for rhabdovirus RNA. Four samples were found positive for viral RNA representing sequences of four different, not previously describ

Transcription and replication mechanisms of Bunyaviridae and Arenaviridae L proteins.

Bunyaviridae and Arenaviridae virus families include an important number of highly pathogenic viruses for humans. They are enveloped viruses with negative stranded RNA genomes divided into three (bunyaviruses) or two (arenaviruses) segments. Each genome segment is coated by the viral nucleoproteins (NPs) and the polymerase (L protein) to form a functional ribonucleoprotein (RNP) complex. The viral RNP provides the necessary context on which the L protein carries out the biosynthetic processes of RNA replication and gene transcription. Decades of research have provided a good understanding of t

Nonreplicative homologous RNA recombination: promiscuous joining of RNA pieces?

Biologically important joining of RNA pieces in cells, as exemplified by splicing and some classes of RNA editing, is posttranscriptional, whereas in RNA viruses it is generally believed to occur during viral RNA polymerase-dependent RNA synthesis. Here, we demonstrate the assembly of precise genome of an RNA virus (poliovirus) from its cotransfected fragments, which does not require specific RNA sequences, takes place before generation of the viral RNA polymerase, and occurs in different ways: Apparently unrestricted ligation of the terminal nucleotides, joining of any one of the two entire f…

Multiplexed Detection, Partitioning, and Persistence of Wild-Type and Vaccine Strains of Measles, Mumps, and Rubella Viruses in Wastewater.

Wastewater surveillance of vaccine-preventable diseases may provide early warning of outbreaks and identify areas to target for immunization. To advance wastewater monitoring of measles, mumps, and rubella viruses, we developed and validated a multiplexed RT-ddPCR assay for the detection of their RNA. Because the measles-mumps-rubella (MMR) vaccine is an attenuated live virus vaccine, we also developed an assay that distinguishes between wild-type and vaccine strains of measles in wastewater and validated it using a wastewater sample collected from a facility with an active measles outbreak. W

Synthesis of Nucleosides and Non-nucleosides Based 4,6-disubstituted-2-oxo-dihydropyridine-3-carbonitriles as Antiviral Agents.

BACKGROUND: Viral diseases are considered main threats that face the humanity worldwide. The emergence of new viruses like influenza viruses emphasizes the significance of designing novel antiviral drugs. METHOD: The aim of this work is to synthesize a new set of nucleoside and non-nucleoside cyanopyridine, characterized and evaluated for their in vitro antiviral properties against various strains. CONCLUSION: More of the compounds showed variable antiviral potential against a panel of eighteen DNA and RNA viruses. The screening data suggested that the order of activity of the active compoun…

No Increased Detection of Nucleic Acids of CNS-related Viruses in the Brains of Patients with Schizophrenia, Bipolar Disorder, and Autism Spectrum Disorder.

BACKGROUND AND HYPOTHESIS: Viral infections are increasingly recognized in the etiology of psychiatric disorders based on epidemiological an … uses in the genome and transcriptome of patients and controls. STUDY RESULTS: A variety of DNA and RNA viruses related to the central nervous system were detected in the brains of patients with major psychiatric disorders, including viruses belonging to Herpesviridae, Polyomaviridae, Retroviridae, Flaviviridae, Parvoviridae, and Adenoviridae. However, no con …

Efficient incorporation and template-dependent polymerase inhibition are major determinants for the broad-spectrum antiviral activity of remdesivir.

Remdesivir (RDV) is a direct-acting antiviral agent that is approved in several countries for the treatment of coronavirus disease 2019 caused by the severe acute respiratory syndrome coronavirus 2. RDV exhibits broad-spectrum antiviral activity against positive-sense RNA viruses, for example, severe acute respiratory syndrome coronavirus and hepatitis C virus, and nonsegmented negative-sense RNA viruses, for example, Nipah virus, whereas segmented negative-sense RNA viruses such as influenza virus or Crimean-Congo hemorrhagic fever virus are not sensitive to the drug. The reasons for this app…

Discovery of two novel totiviruses from Culex tritaeniorhynchus classifiable in a distinct clade with arthropod-infecting viruses within the family Totiviridae.

Two double-stranded RNA viruses, named Culex tritaeniorhynchus totivirus NJ2 (CTV_NJ2) and NJ3 (CTV_NJ3), were discovered from wild-captured Culex tritaeniorhynchus mosquitoes. The complete genomes (7,624 and 7,612 bp in length) were obtained using RNA sequencing. Both CTV_NJ2 and CTV_NJ3 encode a putative capsid protein and an RNA-dependent RNA polymerase. The most similar strain to CTV_NJ2/3 is Omono River virus strain AK4 (ORV-AK4). The CP and RdRp identities of AK4 are different to CTV_NJ2 (84% and 87%) and CTV_NJ3 (47% and 62%). Phylogenetic analysis showed that taxonomically speaking CTV…

Schlafen 11 Restricts Flavivirus Replication.

Schlafen 11 (Slfn11) is an interferon-stimulated gene that controls the synthesis of proteins by regulating tRNA abundance. Likely through t … hat makes multiple translation-competent copies of the incoming viral genome, we reasoned that (+)ssRNA viruses will be more sensitive to the effect of Slfn11 on protein synthesis than (-)ssRNA viruses. To evaluate this hypothesis, we tested the effects of Slfn11 on the replication of a panel of ssRNA viruses in the human glioblastoma cell line A172, which na …

Dissecting the Species-Specific Virome in Culicoides of Thrace.

Biting midges (Culicoides) are vectors of arboviruses of both veterinary and medical importance. The surge of emerging and reemerging vector … irome of 10 Culicoides species resulted in the identification of the genomic signatures of 14 novel RNA viruses, including three fully assembled viruses and four segmented viruses with at least one segment fully assembled, most of which were significantly divergent from previously identified related viruses from the Solemoviridae, Phasmaviridae, Phenuiviridae …

Acquisition of Avian-Origin PB1 Facilitates Viral RNA Synthesis by the 2009 Pandemic H1N1 Virus Polymerase.

The constant crosstalk between the large avian reservoir of influenza A viruses (IAV) and its mammalian hosts drives viral evolution and facilitates their host switching. Direct adaptation of an avian strain to human or reassortment between avian-origin gene segments with that of human strains are the two mechanisms for the emergence of pandemic viruses. While it was suggested that the 1918 pandemic virus is of avian origin, reassortment of 1918 human isolates and avian influenza viruses led to the generation of 1957 and 1968 pandemic viruses. Interestingly, the avian PB1 segment, which encode