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Coltiviruses isolated from mosquitoes collected in Indonesia.

Viruses with genomes consisting of 12 segments of double-stranded (ds) RNA were isolated from mosquito pools collected in Indonesia in 1980 and 1981. The genome segments of 11 virus isolates exhibited two distinct electrophoretic patterns in agarose gels, and the viruses probably represent distinct groups of Coltiviruses. Ten of the 11 virus isolates produced recognizably similar PAGE profiles of two groups of 6 segments (6-6) with 3 distinct profile variants, and the remaining virus isolate displayed a unique 6-5-1 profile. These profiles were distinct from that of Colorado tick fever (CTF) v

Particles containing RNA-instructed DNA polymerase and virus-related RNA in human breast cancers.

Human breast cancers contain an RNA related to that of mouse mammary tumor virus. In 79% of the breast malignancies examined, this type of RNA is a 70S-component encapsulated with RNA-instructed DNA polymerase in a particle possessing the density characteristics of RNA tumor viruses. Further, the DNA synthesized by the human RNA enzyme complex hybridizes specifically with the RNA of mouse mammary tumor virus. Thus, four features diagnostic of agents similar to mouse mammary tumor virus are also exhibited by a particle found with high frequency in human breast cancers. The accumulating evidence

Histopathological, Immunohistochemical and In-Situ Hybridization Findings in Suckling Rats Experimentally Infected With Akabane Genogroups Ⅰ and Ⅱ, Aino and Peaton Viruses.

Akabane, Aino and Peaton viruses are closely related arthropod-borne viruses in the genus Orthobunyavirus of the family Peribunyaviridae that can cause congenital abnormalities in cattle, sheep and goats. East Asian Akabane virus strains are subdivided into genogroups Ⅰ and Ⅱ, and the former can also cause non-suppurative encephalomyelitis in post-natal animals. Specific detection of the infecting virus in tissues is essential for accurate diagnosis. Immunohistochemistry (IHC) has been used to identify viral antigen but cannot always detect specific viruses due to potential cross-reactivity of

Toward in planta studies of persistent fungal viruses in a model plant.

A model plant, Nicotiana benthamiana, was examined as a host for persistent fungal viruses capable of crossing organismal kingdoms. Protoplasts of N. benthamiana were transfected with a mixture of virions of a betapartitivirus, Rosellinia necatrix partitivirus 18 (RnPV18), and an alphapartitivirus, RnPV19, and were then subjected to plantlet regeneration. Primary RT-PCR-based screening showed that nearly 100% of the resulting calli tested positive for RnPV18, whereas approximately 90% were positive for RnPV19. However, secondary screening performed at a later stage of tissue culture revealed t

Respiratory virus shedding in exhaled breath and efficacy of face masks.

We identified seasonal human coronaviruses, influenza viruses and rhinoviruses in exhaled breath and coughs of children and adults with acute respiratory illness. Surgical face masks significantly reduced detection of influenza virus RNA in respiratory droplets and coronavirus RNA in aerosols, with a trend toward reduced detection of coronavirus RNA in respiratory droplets. Our results indicate that surgical face masks could prevent transmission of human coronaviruses and influenza viruses from symptomatic individuals.

Polymerase trapping as the mechanism of H5 highly pathogenic avian influenza virus genesis.

Highly pathogenic avian influenza viruses (HPAIVs) derive from H5 and H7 low pathogenic avian influenza viruses (LPAIVs). Although insertion … result from an RNA structure-driven diversity-generating mechanism, which could also occur in other RNA viruses.

Evolution of transient RNA structure-RNA polymerase interactions in respiratory RNA virus genomes.

RNA viruses are important human pathogens that cause seasonal epidemics and occasional pandemics. Examples are influenza A viruses (IAV) and coronaviruses (CoV). When emerging IAV and CoV spill over to humans, they adapt to evade immune responses and optimize their replication and spread in human cells. In IAV, adaptation occurs in all viral proteins, including the viral ribonucleoprotein (RNP) complex. RNPs consists of a copy of the viral RNA polymerase, a double-helical coil of nucleoprotein, and one of the eight segments of the IAV RNA genome. The RNA segments and their transcripts are part…

Development of a Taqman RT-PCR assay for the detection and quantification of negatively stranded RNA of human enteroviruses: evidence for false-priming and improvement by tagged RT-PCR.

Human enteroviruses are among the most common viruses infecting humans. These viruses are known to be able to infect a wide range of tissues and are believed to establish persistent infections. Enteroviruses are positive-sense single-stranded RNA viruses whose replication involves the synthesis of negative strand intermediates. Therefore, the specific detection of negatively stranded viral RNA in tissues or cells is a reliable marker of active enteroviral replication. The present report presents the development of a real-time RT-PCR allowing the specific detection and quantification of negativ…

Гелькватский комплекс, как потный ингибатор флавивиралов и коронавиральных полимеразов.

Вирусы РНК (RNA (RNA) в позитивном мышлении оказались важными патогенами, способными угрожать современным обществам и наносить им серьезный ущерб, о чем свидетельствует продолжающаяся пандемия COVID-19. Поэтому срочно необходимы соединения, действующие против большинства или многих +РНК. Здесь мы представляем PR673, соединение, похожее на гелькват, способное сдерживать воспроизведение вируса SARS-COV-2 и вируса энцефалита тика в клеточной культуре. Используя анализы in vitro полимеразы, мы показываем, что PR673 препятствует синтезу RNA вирусным RNA-зависимым от RNA полимеразам (RdRps). Наши ре

Совпадение в аннотации оригинала
Positive-sense single-stranded RNA (+RNA) viruses have proven to be important pathogens that are able to threaten and deeply damage modern societies, as illustrated by the ongoing COVID-19 pandemic. Therefore, compounds active against most or many +RNA viruses are urgently needed. Here, we present PR673, a helquat-like compound that is able to inhibit the re…

RNA-Free and Ribonucleoprotein-Associated Influenza Virus Polymerases Directly Bind the Serine-5-Phosphorylated Carboxyl-Terminal Domain of Host RNA Polymerase II.

UNLABELLED: Influenza viruses subvert the transcriptional machinery of their hosts to synthesize their own viral mRNA. Ongoing transcription by cellular RNA polymerase II (Pol II) is required for viral mRNA synthesis. By a process known as cap snatching, the virus steals short 5' capped RNA fragments from host capped RNAs and uses them to prime viral transcription. An interaction between the influenza A virus RNA polymerase and the C-terminal domain (CTD) of the large subunit of Pol II has been established, but the molecular details of this interaction remain unknown. We show here that the inf

RNA virus diversity and prevalence in field and laboratory populations of melon fly throughout its distribution.

Insects have a rich diversity of RNA viruses that can either cause acute infections or persist in host populations without visible symptoms. The melon fly, Zeugodacus cucurbitae (Tephritidae) causes substantial economic losses through infestation of diverse cucurbit and other crops. Of Indomalayan origin, it is now established in many tropical regions of the world. The virome diversity of Z. cucurbitae is largely unknown across large parts of its distribution, including the Indian subcontinent. We have analysed three transcriptomes each of one field-collected and one laboratory-reared Z. cucur…

Landscape and ecological correlates of tick-associated viruses in Inner Mongolia, China.

INTRODUCTION: Ticks harbour complex RNA viromes containing both confirmed pathogens and numerous viruses with unknown transmission routes. D … dy identified 146 RNA viral sequences representing 36 viral species, including seven putative novel RNA viruses. The virome also contained several known tick-borne viruses (TBVs), including Alongshan virus (ALSV), tick-borne encephalitis virus (TBEV), and Beiji nairovirus (BJNV). These pathogens showed high genetic diversity and recombination signals in easte …

Molecular biology of viral hepatitis and hepatocellular carcinoma.

Five viruses are the major causes of hepatitis. These viruses are totally unrelated to each other in structure and mode of replication despite the similarity in the acute syndrome produced by each virus. HAV is a single-stranded RNA virus that has a very stable capsid and whose proteins are derived from a single polyprotein. HBV is a DNA virus that replicates through an RNA intermediate. HCV is a labile single-stranded RNA virus whose proteins are derived from a polyprotein. HDV is a defective RNA virus related to viroids that encodes a capsid antigen, delta antigen, and requires the envelope

Crystal structure of the rabies virus nucleoprotein-RNA complex.

Negative-strand RNA viruses condense their genome into a helical nucleoprotein-RNA complex, the nucleocapsid, which is packed into virions and serves as a template for the RNA-dependent RNA polymerase complex. The crystal structure of a recombinant rabies virus nucleoprotein-RNA complex, organized in an undecameric ring, has been determined at 3.5 angstrom resolution. Polymerization of the nucleoprotein is achieved by domain exchange between protomers, with flexible hinges allowing nucleocapsid formation. The two core domains of the nucleoprotein clamp around the RNA at their interface and shi…

A microarray-based pathogen chip for simultaneous molecular detection of transfusion-transmitted infectious agents.

BACKGROUND: New and emerging transfusion-transmitted infections remain a threat to the blood supply. Blood donors are currently screened for … rray-based platform (pathogen chip) for simultaneous molecular detection of transfusion-transmitted RNA viruses. METHODS: Sixteen RNA viruses that pose a significant risk for transfusion-transmission were selected for inclusion on the pathogen chip. Viruses were targeted for detection by 1769 oligonucleotide probes selected by Agilent eArray software. Differ …

Characterization and Tissue Tropism of Newly Identified Iflavirus and Negeviruses in Glossina morsitans morsitans Tsetse Flies.

Tsetse flies cause major health and economic problems as they transmit trypanosomes causing sleeping sickness in humans (Human African Trypa … t viruses threaten tsetse mass production. Here we demonstrated the presence of two single-stranded RNA viruses isolated from Glossina morsitans morsitans originating from a colony at the Seibersdorf rearing facility. The genome organization and the phylogenetic analysis based on the RNA-dependent RNA polymerase (RdRp) revealed that the two viruses belong to …

Endomembrane targeting of human OAS1 p46 augments antiviral activity.

Many host RNA sensors are positioned in the cytosol to detect viral RNA during infection. However, most positive-strand RNA viruses replicate within a modified organelle co-opted from intracellular membranes of the endomembrane system, which shields viral products from cellular innate immune sensors. Targeting innate RNA sensors to the endomembrane system may enhance their ability to sense RNA generated by viruses that use these compartments for replication. Here, we reveal that an isoform of oligoadenylate synthetase 1, OAS1 p46, is prenylated and targeted to the endomembrane system. Membrane…

Similarities and differences in hepatitis B and C virus induced hepatocarcinogenesis.

Hepatocellular carcinoma (HCC), the major manifestation of primary liver cancer, is one of the most frequent and malignant diseases worldwide. Among other environmental factors, hepatitis viruses, as the hepatitis B (HBV) and hepatitis C (HCV) viruses, are to be listed in the etiology of HCC. Both of these viruses cause a wide spectrum of clinical manifestations, ranging from healthy carrier state to acute and chronic hepatitis, cirrhosis and HCC. HBV and HCV are different viruses in structure: HBV contains a DNA genome which replicates through an RNA intermediate and requires an active viral

Characterization of a novel Iflavirus from the locust Calliptamus italicus in Xinjiang, China.

Insect-specific viruses represent a promising yet underexplored resource for the biological control of locust pests. In this study, we performed metatranscriptomic sequencing of three dominant locust species-Calliptamus italicus, Calliptamus barbarus, and Oedaleus decorus decorus-collected from field populations in Xinjiang, China. Bioinformatic analysis identified 32 RNA viruses, 137 DNA viruses, and 33 unclassified viruses. Notably, this study reports the first detection of a novel insect-specific virus in locusts. Phylogenetic and homology analyses revealed that the newly discovered virus b…

Evolution of transient RNA structure-RNA polymerase interactions in respiratory RNA virus genomes.

RNA viruses are important human pathogens that cause seasonal epidemics and occasional pandemics. Examples are influenza A viruses (IAV) and coronaviruses (CoV). When emerging IAV and CoV spill over to humans, they adapt to evade immune responses and optimize their replication and spread in human cells. In IAV, adaptation occurs in all viral proteins, including the viral ribonucleoprotein (RNP) complex. RNPs consist of a copy of the viral RNA polymerase, a double-helical coil of nucleoprotein, and one of the eight segments of the IAV RNA genome. The RNA segments and their transcripts are parti…