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International Journal of Molecular... Nov 2023Herpesviruses are large DNA viruses that have long been used as powerful gene therapy tools. In recent years, the ability of herpesviruses to stimulate both innate and... (Review)
Review
Herpesviruses are large DNA viruses that have long been used as powerful gene therapy tools. In recent years, the ability of herpesviruses to stimulate both innate and adaptive immune responses has led to their transition to various applications as vaccine vectors. This vaccinology branch is growing at an unprecedented and accelerated rate. To date, human herpesvirus-based vectors have been used in vaccines to combat a variety of infectious agents, including the Ebola virus, foot and mouth disease virus, and human immunodeficiency viruses. Additionally, these vectors are being tested as potential vaccines for cancer-associated antigens. Thanks to advances in recombinant DNA technology, immunology, and genomics, numerous steps in vaccine development have been greatly improved. A better understanding of herpesvirus biology and the interactions between these viruses and the host cells will undoubtedly foster the use of herpesvirus-based vaccine vectors in clinical settings. To overcome the existing drawbacks of these vectors, ongoing research is needed to further advance our knowledge of herpesvirus biology and to develop safer and more effective vaccine vectors. Advanced molecular virology and cell biology techniques must be used to better understand the mechanisms by which herpesviruses manipulate host cells and how viral gene expression is regulated during infection. In this review, we cover the underlying molecular structure of herpesviruses and the strategies used to engineer their genomes to optimize capacity and efficacy as vaccine vectors. Also, we assess the available data on the successful application of herpesvirus-based vaccines for combating diseases such as viral infections and the potential drawbacks and alternative approaches to surmount them.
Topics: Humans; Herpesviridae; Simplexvirus; Virus Diseases; Viral Vaccines; Genetic Vectors
PubMed: 38003300
DOI: 10.3390/ijms242216112 -
Virus Research Jan 2021RNA helicase A (RHA) is a ubiquitously expressed DExH-box helicase enzyme that is involved in a wide range of biological processes including transcription, translation,... (Review)
Review
RNA helicase A (RHA) is a ubiquitously expressed DExH-box helicase enzyme that is involved in a wide range of biological processes including transcription, translation, and RNA processing. A number of RNA viruses recruit RHA to the viral RNA to facilitate virus replication. DNA viruses contain a DNA genome and replicate using a DNA-dependent DNA polymerase. RHA has also been reported to associate with some DNA viruses during replication, in which the enzyme acts on the viral RNA or protein products. As shown for Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus, RHA has potential to allow the virus to control a switch in cellular gene expression to modulate the antiviral response. While the study of the interaction of RHA with DNA viruses is still at an early stage, preliminary evidence indicates that the underlying molecular mechanisms are diverse. We now review the current status of this emerging field.
Topics: DEAD-box RNA Helicases; DNA Replication; DNA Viruses; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Herpesvirus 8, Human; Host Microbial Interactions; Humans; Neoplasm Proteins; RNA, Viral; Virus Replication
PubMed: 33132162
DOI: 10.1016/j.virusres.2020.198206 -
ACS Chemical Biology Aug 2023The constant and the sudden emergence of zoonotic human and animal viruses is a significant threat to human health, the world economy, and the world food supply. This...
The constant and the sudden emergence of zoonotic human and animal viruses is a significant threat to human health, the world economy, and the world food supply. This has necessitated the development of broad-spectrum therapeutic strategies to combat these emerging pathogens. Mechanisms that are essential for viral replication and propagation have been successfully targeted in the past to develop broad-spectrum therapeutics that can be readily repurposed to combat new zoonotic pathogens. Because of the importance of viral RNA capping enzymes to viral replication and pathogenesis, as well as their presence in both DNA and RNA viruses, these viral proteins have been a long-standing therapeutic target. Here, we use genome sequencing information and yeast-based platforms (YeRC0M) to identify, characterize, and target viral genome-encoded essential RNA capping enzymes from emerging strains of DNA viruses, i.e., Monkeypox virus and African Swine Fever Virus, which are a significant threat to human and domestic animal health. We first identified and biochemically characterized these viral RNA capping enzymes and their necessary protein domains. We observed significant differences in functional protein domains and organization for RNA capping enzymes from emerging DNA viruses in comparison to emerging RNA viruses. We also observed several differences in the biochemical properties of these viral RNA capping enzymes using our phenotypic yeast-based approaches (YeRC0M) as compared to the previous in vitro studies. Further, using directed evolution, we were able to identify inactivation and attenuation mutations in these essential viral RNA capping enzymes; these data could have implications on virus biocontainment as well as live attenuated vaccine development. We also developed methods that would facilitate high-throughput phenotypic screening to identify broad-spectrum inhibitors that selectively target viral RNA capping enzymes over host RNA capping enzymes. As demonstrated here, our approaches to identify, characterize, and target viral genome-encoded essential RNA capping enzymes are highly modular and can be readily adapted for targeting emerging viral pathogens as well as their variants that emerge in the future.
Topics: Animals; Humans; Swine; Saccharomyces cerevisiae; African Swine Fever Virus; Viruses; RNA, Viral; Virus Replication; DNA Viruses
PubMed: 37498174
DOI: 10.1021/acschembio.3c00243 -
Journal of Virological Methods Oct 2023The ability of viral metagenomic Next-Generation Sequencing (mNGS) to unbiasedly detect nucleic acids in a clinical sample is a powerful tool for advanced diagnosis of...
The ability of viral metagenomic Next-Generation Sequencing (mNGS) to unbiasedly detect nucleic acids in a clinical sample is a powerful tool for advanced diagnosis of viral infections. When clinical symptoms do not provide a clear differential diagnosis, extensive laboratory testing with virus-specific PCR and serology can be replaced by a single viral mNGS analysis. However, widespread diagnostic use of viral mNGS is thus far limited by long sample-to-result times, as most protocols rely on Illumina sequencing, which provides high and accurate sequencing output but is time-consuming and expensive. Here, we describe the development of an mNGS protocol based on the more cost-effective Nanopore Flongle sequencing with decreased turnaround time and lower, yet sufficient sequencing output to provide sensitive virus detection. Sample preparation (6 h) and sequencing (2 h) times are substantially reduced compared to Illumina mNGS and allow detection of DNA/RNA viruses at low input (up to 33-38 cycle threshold of specific qPCR). Although Flongles yield lower sequencing output, direct comparison with Illumina mNGS on diverse clinical samples showed similar results. Collectively, the novel Nanopore mNGS approach is specifically tailored for use in clinical diagnostics and provides a rapid and cost-effective mNGS strategy for individual testing of severe cases.
Topics: Humans; Metagenomics; Nanopores; Virus Diseases; Viruses; RNA Viruses; DNA Viruses; High-Throughput Nucleotide Sequencing; Sensitivity and Specificity
PubMed: 37516367
DOI: 10.1016/j.jviromet.2023.114784 -
Journal of Visualized Experiments : JoVE May 2024We report a fast, easy-to-implement, highly sensitive, sequence-specific, and point-of-care (POC) DNA virus detection system, which combines recombinase polymerase...
We report a fast, easy-to-implement, highly sensitive, sequence-specific, and point-of-care (POC) DNA virus detection system, which combines recombinase polymerase amplification (RPA) and CRISPR/Cas12a system for trace detection of DNA viruses. Target DNA is amplified and recognized by RPA and CRISPR/Cas12a separately, which triggers the collateral cleavage activity of Cas12a that cleaves a fluorophore-quencher labeled DNA reporter and generalizes fluorescence. For POC detection, portable smartphone microscopy is built to take fluorescent images. Besides, deep learning models for binary classification of positive or negative samples, achieving high accuracy, are deployed within the system. Frog virus 3 (FV3, genera Ranavirus, family Iridoviridae) was tested as an example for this DNA virus POC detection system, and the limits of detection (LoD) can achieve 10 aM within 40 min. Without skilled operators and bulky instruments, the portable and miniature RPA-CRISPR/Cas12a-SPM with artificial intelligence (AI) assisted classification shows great potential for POC DNA virus detection and can help prevent the spread of such viruses.
Topics: CRISPR-Cas Systems; Deep Learning; Ranavirus; Nucleic Acid Amplification Techniques; DNA Viruses; Recombinases; DNA, Viral; Point-of-Care Systems
PubMed: 38801262
DOI: 10.3791/64833 -
The Journal of General Virology Jul 2021Members of the family have linear dsDNA genomes of 27 to 29 kbp and are the first viruses known to infect mesophilic ammonia-oxidizing archaea of the phylum...
Members of the family have linear dsDNA genomes of 27 to 29 kbp and are the first viruses known to infect mesophilic ammonia-oxidizing archaea of the phylum Thaumarchaeota. The spindle-shaped virions of Nitrosopumilus spindle-shaped virus 1 possess short tails at one pole and measure 64±3 nm in diameter and 112±6 nm in length. This morphology is similar to that of members of the families and . Virus replication is not lytic but leads to growth inhibition of the host. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family which is available at ictv.global/report/thaspiviridae.
Topics: Archaea; Archaeal Viruses; DNA Viruses; Genome, Viral; Host Specificity; Virion; Virus Replication
PubMed: 34328827
DOI: 10.1099/jgv.0.001631 -
Viruses Nov 2020Giant viruses are a group of eukaryotic double-stranded DNA viruses with large virion and genome size that challenged the traditional view of virus. Newly isolated... (Review)
Review
Giant viruses are a group of eukaryotic double-stranded DNA viruses with large virion and genome size that challenged the traditional view of virus. Newly isolated strains and sequenced genomes in the last two decades have substantially advanced our knowledge of their host diversity, gene functions, and evolutionary history. Giant viruses are now known to infect hosts from all major supergroups in the eukaryotic tree of life, which predominantly comprises microbial organisms. The seven well-recognized viral clades (taxonomic families) have drastically different host range. and , both with notable intrafamilial genome variation and high abundance in environmental samples, have members that infect the most diverse eukaryotic lineages. Laboratory experiments and comparative genomics have shed light on the unprecedented functional potential of giant viruses, encoding proteins for genetic information flow, energy metabolism, synthesis of biomolecules, membrane transport, and sensing that allow for sophisticated control of intracellular conditions and cell-environment interactions. Evolutionary genomics can illuminate how current and past hosts shape viral gene repertoires, although it becomes more obscure with divergent sequences and deep phylogenies. Continued works to characterize giant viruses from marine and other environments will further contribute to our understanding of their host range, coding potential, and virus-host coevolution.
Topics: Animals; Eukaryota; Evolution, Molecular; Genome Size; Genome, Viral; Genomics; Giant Viruses; Host Specificity; Humans; Phylogeny
PubMed: 33233432
DOI: 10.3390/v12111337 -
Viruses Oct 2020Curcumin, the primary curcuminoid compound found in turmeric spice, has shown broad activity as an antimicrobial agent, limiting the replication of many different fungi,... (Review)
Review
Curcumin, the primary curcuminoid compound found in turmeric spice, has shown broad activity as an antimicrobial agent, limiting the replication of many different fungi, bacteria and viruses. In this review, we summarize recent studies supporting the development of curcumin and its derivatives as broad-spectrum antiviral agents.
Topics: Animals; Antiviral Agents; Curcuma; Curcumin; DNA Viruses; Humans; Mice; RNA Viruses; Virus Diseases
PubMed: 33142686
DOI: 10.3390/v12111242 -
International Journal of Molecular... Jul 2019The extracellular signal-regulated kinases (ERKs) comprise a particular branch of the mitogen-activated protein kinase cascades (MAPK) that transmits extracellular... (Review)
Review
The extracellular signal-regulated kinases (ERKs) comprise a particular branch of the mitogen-activated protein kinase cascades (MAPK) that transmits extracellular signals into the intracellular environment to trigger cellular growth responses. Similar to other MAPK cascades, the MAPK-ERK pathway signals through three core kinases-Raf, MAPK/ERK kinase (MEK), and ERK-which drive the signaling mechanisms responsible for the induction of cellular responses from extracellular stimuli including differentiation, proliferation, and cellular survival. However, pathogens like DNA viruses alter MAPK-ERK signaling in order to access DNA replication machineries, induce a proliferative state in the cell, or even prevent cell death mechanisms in response to pathogen recognition. Differential utilization of this pathway by multiple DNA viruses highlights the dynamic nature of the MAPK-ERK pathway within the cell and the importance of its function in regulating a wide variety of cellular fates that ultimately influence viral infection and, in some cases, result in tumorigenesis.
Topics: DNA Virus Infections; DNA Viruses; Extracellular Signal-Regulated MAP Kinases; Host-Pathogen Interactions; Humans; MAP Kinase Signaling System; Mitogen-Activated Protein Kinases; Protein Binding
PubMed: 31336840
DOI: 10.3390/ijms20143427 -
Nature Structural & Molecular Biology May 2021Certain large DNA viruses, including those in the Marseilleviridae family, encode histones. Here we show that fused histone pairs Hβ-Hα and Hδ-Hγ from Marseillevirus...
Certain large DNA viruses, including those in the Marseilleviridae family, encode histones. Here we show that fused histone pairs Hβ-Hα and Hδ-Hγ from Marseillevirus are structurally analogous to the eukaryotic histone pairs H2B-H2A and H4-H3. These viral histones form 'forced' heterodimers, and a heterotetramer of four such heterodimers assembles DNA to form structures virtually identical to canonical eukaryotic nucleosomes.
Topics: DNA; DNA Viruses; Histones; Nucleosomes; Protein Binding; Protein Structural Elements; Protein Structure, Tertiary
PubMed: 33927388
DOI: 10.1038/s41594-021-00585-7