Endogénne retrovírusy (ERV) sú genetické elementy, ktoré boli integrované do genómu hostiteľa pred viac ako 100 miliónmi rokov. Ich integrácia prebehla v zárodočných bunkách, čím sa v ľudskej populácii zabezpečil ich prenos z generácie na generáciu. V súčasnosti sa predpokladá, že tvoria až 8 % ľudského genómu. V priebehu evolúcie došlo v endogénnych retrovírusoch ku hromadeniu rôznych mutácii, čo viedlo k ich znefunkčneniu, a preto sa v minulosti považovali za odpadovú DNA. V posledných rokoch sa však ukazuje, že nie sú úplne nefunkčné. S pribúdajúcimi analýzami ľudského genómu sa odhaľujú ich potenciálne úlohy aj v ľudskom organizme.
Endogenous retroviruses (ERVs) are genetic elements that were integrated into the host genome more than 100 million years ago. Their integration took place in germ cells, ensuring their vertical transmission in the human population. They are currently thought to make up to 8 % of the human genome. During evolution, various mutations have accumulated in endogenous retroviruses, leading to their dysfunction, and were therefore considered as junk DNA in the past. However, in recent years it has turned out that they are not completely dysfunctional. With more data becoming available from human genome analyses, their potential roles in the human body are being revealed.
- MeSH
- autoimunitní nemoci etiologie virologie MeSH
- endogenní retroviry * genetika metabolismus MeSH
- genom lidský genetika MeSH
- genom virový genetika MeSH
- integrace viru genetika MeSH
- lidé MeSH
- Retroviridae - proteiny onkogenní genetika metabolismus MeSH
- Retroviridae genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Herein, we report, for the first time, the screening of several ligands in terms of their ability to bind and stabilize G-quadruplexes (G4) found in seven human Papillomavirus (HPV) genomes. Using a variety of biophysical assays, HPV G-quadruplexes were shown to possess a high degree of structural polymorphism upon ligand binding, which may have an impact on transcription, replication, and viral protein production. A sequence found in high-risk HPV16 genotype folds into multiple non-canonical DNA structures; it was converted into a major G4 conformation upon interaction with a well-characterized highly selective G4 ligand, PhenDC3, which may have an impact on the viral infection. Likewise, HPV57 and 58, which fold into multiple G4 structures, were found to form single stable complexes in the presence of two other G4 ligands, C8 and pyridostatin, respectively. In addition, one of the selected compounds, the acridine derivative C8, demonstrated a significant antiviral effect in HPV18-infected organotypic raft cultures. Altogether, these results indicate that targeting HPV G4s may be an alternative route for the development of novel antiviral therapies.
- MeSH
- aminochinoliny farmakologie MeSH
- cílená molekulární terapie MeSH
- DNA vazebné proteiny genetika MeSH
- G-kvadruplexy účinky léků MeSH
- genom virový účinky léků genetika MeSH
- genotyp MeSH
- komplement C8 genetika farmakologie MeSH
- konformace nukleové kyseliny účinky léků MeSH
- kyseliny pikolinové farmakologie MeSH
- lidé MeSH
- lidský papilomavirus 16 účinky léků genetika patogenita ultrastruktura MeSH
- lidský papilomavirus 18 účinky léků genetika ultrastruktura MeSH
- ligandy MeSH
- virové nemoci farmakoterapie genetika patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Anelloviruses are small negative-sense single-stranded DNA viruses with genomes ranging in size from 1.6 to 3.9 kb. The family Anelloviridae comprised 14 genera before the present changes. However, in the last five years, a large number of diverse anelloviruses have been identified in various organisms. Here, we undertake a global analysis of mammalian anelloviruses whose full genome sequences have been determined and have an intact open reading frame 1 (ORF1). We established new criteria for the classification of anelloviruses, and, based on our analyses, we establish new genera and species to accommodate the unclassified anelloviruses. We also note that based on the updated species demarcation criteria, some previously assigned species (n = 10) merge with other species. Given the rate at which virus sequence data are accumulating, and with the identification of diverse anelloviruses, we acknowledge that the taxonomy will have to be dynamic and continuously evolve to accommodate new members.
- MeSH
- Anelloviridae klasifikace genetika MeSH
- databáze genetické MeSH
- DNA virů genetika MeSH
- fylogeneze MeSH
- genom virový genetika MeSH
- otevřené čtecí rámce genetika MeSH
- savci virologie MeSH
- sekvence nukleotidů MeSH
- terminologie jako téma MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The genus Gyrovirus was assigned to the family Anelloviridae in 2017 with only one recognized species, Chicken anemia virus. Over the last decade, many diverse viruses related to chicken anemia virus have been identified but not classified. Here, we provide a framework for the classification of new species in the genus Gyrovirus and communicate the establishment of nine new species. We adopted the 'Genus + freeform epithet' binomial system for the naming of these species.
- MeSH
- Anelloviridae klasifikace genetika MeSH
- databáze genetické MeSH
- DNA virů genetika MeSH
- fylogeneze MeSH
- genom virový genetika MeSH
- Gyrovirus klasifikace genetika MeSH
- lidé MeSH
- sekvenční analýza DNA MeSH
- terminologie jako téma * MeSH
- virové plášťové proteiny genetika MeSH
- virus anemie kuřat klasifikace genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Rotavirus genomes are distributed between 11 distinct RNA molecules, all of which must be selectively copackaged during virus assembly. This likely occurs through sequence-specific RNA interactions facilitated by the RNA chaperone NSP2. Here, we report that NSP2 autoregulates its chaperone activity through its C-terminal region (CTR) that promotes RNA-RNA interactions by limiting its helix-unwinding activity. Unexpectedly, structural proteomics data revealed that the CTR does not directly interact with RNA, while accelerating RNA release from NSP2. Cryo-electron microscopy reconstructions of an NSP2-RNA complex reveal a highly conserved acidic patch on the CTR, which is poised toward the bound RNA. Virus replication was abrogated by charge-disrupting mutations within the acidic patch but completely restored by charge-preserving mutations. Mechanistic similarities between NSP2 and the unrelated bacterial RNA chaperone Hfq suggest that accelerating RNA dissociation while promoting intermolecular RNA interactions may be a widespread strategy of RNA chaperone recycling.
- MeSH
- elektronová kryomikroskopie MeSH
- genom virový genetika MeSH
- molekulární chaperony metabolismus MeSH
- molekulární modely MeSH
- proteiny vázající RNA metabolismus MeSH
- ribonukleoproteiny metabolismus MeSH
- RNA virová genetika MeSH
- Rotavirus genetika růst a vývoj metabolismus MeSH
- sbalování RNA genetika MeSH
- virové nestrukturální proteiny metabolismus MeSH
- zabalení virového genomu genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Two novel dsDNA bacteriophages named Pectobacterium virus CB251 (PcCB251) and Pectobacterium virus CB7V (PcCB7V) targeting plant pathogen Pectobacterium parmentieri have been isolated and sequenced. The PcCB251 genome consists of 40,557 bp with G+C content of 48.6% and contains 47 predicted genes on a single strand. The phage is classified in genus Berlinvirus, family Autographiviridae. The PcCB7V phage has a circular dsDNA genome of 146,054 bp with G+C content of 50.4% and contains 269 predicted protein genes on both strands and 13 tRNA genes. The PcCB7V phage can be classified in genus Certrevirus, subfamily Vequintavirinae. Both novel bacteriophages have narrow host ranges, but they extend the list of candidates for phage-based control of pectolytic bacteria causing soft rot disease of potato.
Polyomaviruses are ancient DNA viruses that infect several species of animals. While recognition of the family Polyomaviridae has grown rapidly, there are few studies that consider their potential association with disease. Carnivora are a diverse and widespread order affected by polyomaviruses (PyVs) that have co-evolved with their hosts for millions of years. PyVs have been identified in sea lions, raccoons, badgers, Weddell seals, and dogs. We have discovered a polyomavirus, tentatively named "Ursus americanus polyomavirus 1" (UaPyV1) in black bears (Ursus americanus). UaPyV1 was detectable in various tissues of six out of seven bears submitted for necropsy. Based on viral phylogenetic clustering and detection of the virus in multiple individuals, we suggest that black bears are the natural hosts for UaPyV1. In this albeit small group, there is no clear relationship between UaPyV1 infection and any specific disease.
- MeSH
- DNA virů genetika MeSH
- fylogeneze MeSH
- genom virový genetika MeSH
- infekce onkogenními viry patologie veterinární virologie MeSH
- medvědovití virologie MeSH
- polyomavirové infekce patologie veterinární virologie MeSH
- Polyomavirus klasifikace genetika MeSH
- sekvence nukleotidů MeSH
- virové proteiny genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Spojené státy americké MeSH
Seven novel tailed lytic viruses (Ds3CZ, Ds5CZ, Ds9CZ, Ds16CZ, Ds20CZ, Ds23CZ, Ds25CZ) infecting the bacterium Dickeya solani were isolated in the Czech Republic. Genomes of these viruses are dsDNA, 149,364 to 155,285 bp in length, and the genome arrangement is very similar to that of the type virus Dickeya virus LIMEstone 1. All but the Ds25CZ virus should be regarded as strains of a single species. Most of the sequence differences are due to the presence or absence of homing endonuclease (HE) genes, with 23 HEs found in Ds3CZ, Ds5CZ, and Ds20CZ, 22 in Ds9CZ, 19 in Ds16CZ, 18 in Ds25CZ, and 15 in Ds23CZ.
- MeSH
- Caudovirales klasifikace genetika izolace a purifikace MeSH
- Dickeya virologie MeSH
- DNA virů genetika MeSH
- endonukleasy genetika MeSH
- fylogeneze MeSH
- genetická variace MeSH
- genom virový genetika MeSH
- nemoci rostlin mikrobiologie virologie MeSH
- Solanum tuberosum mikrobiologie virologie MeSH
- virové proteiny genetika MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
High-throughput sequencing technologies were used to identify plant viruses in cereal samples surveyed from 2012 to 2017. Fifteen genome sequences of a tenuivirus infecting wheat, oats, and spelt in Estonia, Norway, and Sweden were identified and characterized by their distances to other tenuivirus sequences. Like most tenuiviruses, the genome of this tenuivirus contains four genomic segments. The isolates found from different countries shared at least 92% nucleotide sequence identity at the genome level. The planthopper Javesella pellucida was identified as a vector of the virus. Laboratory transmission tests using this vector indicated that wheat, oats, barley, rye, and triticale, but none of the tested pasture grass species (Alopecurus pratensis, Dactylis glomerata, Festuca rubra, Lolium multiflorum, Phleum pratense, and Poa pratensis), are susceptible. Taking into account the vector and host range data, the tenuivirus we have found most probably represents European wheat striate mosaic virus first identified about 60 years ago. Interestingly, whereas we were not able to infect any of the tested cereal species mechanically, Nicotiana benthamiana was infected via mechanical inoculation in laboratory conditions, displaying symptoms of yellow spots and vein clearing evolving into necrosis, eventually leading to plant death. Surprisingly, one of the virus genome segments (RNA2) encoding both a putative host systemic movement enhancer protein and a putative vector transmission factor was not detected in N. benthamiana after several passages even though systemic infection was observed, raising fundamental questions about the role of this segment in the systemic spread in several hosts.
- MeSH
- genom virový * genetika MeSH
- Hemiptera virologie MeSH
- jedlá semena virologie MeSH
- nemoci rostlin virologie MeSH
- rostlinné viry * genetika MeSH
- viry mozaiky * genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Norsko MeSH
- Švédsko MeSH
Despite their ecological importance, nothing is known about the diversity and abundance of RNA viruses in termites (Termitoidae). We used a metatranscriptomics approach to determine the RNA virome structure of 50 diverse species of termite that differ in both phylogenetic position and colony composition. From these samples, we identified 67 novel RNA viruses, characterized their genomes, quantified their abundance and inferred their evolutionary history. These viruses were found within or similar to those from the Togaviridae, Iflaviridae, Polycipiviridae, Flaviviridae, Leviviridae, Narnaviridae, Mitoviridae, Lispivirdae, Phasmaviridae, Picobirnaviridae and Partitiviridae. However, all viruses identified were novel and divergent, exhibiting only 20% to 45% amino acid identity to previously identified viruses. Our analysis suggested that 17 of the viruses identified were termite-infecting, with the remainder likely associated with the termite microbiome or diet. Unclassified sobemo-like and bunya-like viruses dominated termite viromes, while most of the phylogenetic diversity was provided by the picobirna- and mitovirus-like viruses. Of note was the identification of a novel flavi-like virus most closely related to those found in marine vertebrates and invertebrates. Notably, the sampling procedure had the strongest association with virome composition, with greater RNA virome diversity in libraries prepared from whole termite bodies than those that only sampled heads.
