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PloS One 2016Canine herpesvirus is a widespread alphaherpesvirus that causes a fatal haemorrhagic disease of neonatal puppies. We have used high-throughput methods to determine the...
Canine herpesvirus is a widespread alphaherpesvirus that causes a fatal haemorrhagic disease of neonatal puppies. We have used high-throughput methods to determine the genome sequences of three viral strains (0194, V777 and V1154) isolated in the United Kingdom between 1985 and 2000. The sequences are very closely related to each other. The canine herpesvirus genome is estimated to be 125 kbp in size and consists of a unique long sequence (97.5 kbp) and a unique short sequence (7.7 kbp) that are each flanked by terminal and internal inverted repeats (38 bp and 10.0 kbp, respectively). The overall nucleotide composition is 31.6% G+C, which is the lowest among the completely sequenced alphaherpesviruses. The genome contains 76 open reading frames predicted to encode functional proteins, all of which have counterparts in other alphaherpesviruses. The availability of the sequences will facilitate future research on the diagnosis and treatment of canine herpesvirus-associated disease.
Topics: Alphaherpesvirinae; Amino Acid Sequence; Animals; Base Sequence; Chromosome Mapping; Dog Diseases; Dogs; Genes, Viral; Genome, Viral; Hemorrhagic Disorders; Madin Darby Canine Kidney Cells; Open Reading Frames; Sequence Analysis, DNA; Viral Proteins
PubMed: 27213534
DOI: 10.1371/journal.pone.0156015 -
Annual Review of Microbiology 2012Herpes simplex virus, varicella zoster virus, and pseudorabies virus are neurotropic pathogens of the Alphaherpesvirinae subfamily of the Herpesviridae. These viruses... (Review)
Review
Herpes simplex virus, varicella zoster virus, and pseudorabies virus are neurotropic pathogens of the Alphaherpesvirinae subfamily of the Herpesviridae. These viruses efficiently invade the peripheral nervous system and establish lifelong latency in neurons resident in peripheral ganglia. Primary and recurrent infections cycle virus particles between neurons and the peripheral tissues they innervate. This remarkable cycle of infection is the topic of this review. In addition, some of the distinguishing hallmarks of the infections caused by these viruses are evaluated in terms of their underlying similarities.
Topics: Animals; Herpesvirus 1, Suid; Herpesvirus 3, Human; Humans; Nervous System; Simplexvirus; Viral Tropism; Virus Latency
PubMed: 22726218
DOI: 10.1146/annurev-micro-092611-150051 -
Journal of Neuroimmune Pharmacology :... Sep 2010Alphaherpesviruses are a subfamily of the Herpesviridae that can invade the nervous system and establish either lytic or latent infections. The establishment of latent... (Review)
Review
Alphaherpesviruses are a subfamily of the Herpesviridae that can invade the nervous system and establish either lytic or latent infections. The establishment of latent infection can occur only in neurons, indicating a unique virus-host interaction in these cells. Here, we compare results from seven microarray studies that focused on the host response of either neural tissue or isolated neurons to alphaherpesvirus infection. These studies utilized either herpes simplex virus type 1 or pseudorabies virus as the infectious agent. From these data, we have found common host responses spanning a variety of infection models in different species, with different herpesvirus strains, and during all phases of infection including lytic, latent, and reactivation. The repeated observation of transcriptional effects on these genes and gene families indicates their likely importance in host defenses or the viral infectious process. We discuss the possible role of these different genes and genes families in alphaherpesvirus infection.
Topics: Alphaherpesvirinae; Gene Expression Regulation, Viral; Herpesviridae Infections; Humans; Neuroimmunomodulation; Signal Transduction
PubMed: 20401540
DOI: 10.1007/s11481-010-9212-0 -
Viruses Sep 2021An evolutionary arms race occurs between viruses and hosts. Hosts have developed an array of antiviral mechanisms aimed at inhibiting replication and spread of viruses,... (Review)
Review
An evolutionary arms race occurs between viruses and hosts. Hosts have developed an array of antiviral mechanisms aimed at inhibiting replication and spread of viruses, reducing their fitness, and ultimately minimising pathogenic effects. In turn, viruses have evolved sophisticated counter-measures that mediate evasion of host defence mechanisms. A key aspect of host defences is the ability to differentiate between self and non-self. Previous studies have demonstrated significant suppression of CpG and UpA dinucleotide frequencies in the coding regions of RNA and small DNA viruses. Artificially increasing these dinucleotide frequencies results in a substantial attenuation of virus replication, suggesting dinucleotide bias could facilitate recognition of non-self RNA. The interferon-inducible gene, zinc finger antiviral protein (ZAP) is the host factor responsible for sensing CpG dinucleotides in viral RNA and restricting RNA viruses through direct binding and degradation of the target RNA. Herpesviruses are large DNA viruses that comprise three subfamilies, alpha, beta and gamma, which display divergent CpG dinucleotide patterns within their genomes. ZAP has recently been shown to act as a host restriction factor against human cytomegalovirus (HCMV), a beta-herpesvirus, which in turn evades ZAP detection by suppressing CpG levels in the major immediate-early transcript IE1, one of the first genes expressed by the virus. While suppression of CpG dinucleotides allows evasion of ZAP targeting, synonymous changes in nucleotide composition that cause genome biases, such as low GC content, can cause inefficient gene expression, especially in unspliced transcripts. To maintain compact genomes, the majority of herpesvirus transcripts are unspliced. Here we discuss how the conflicting pressures of ZAP evasion, the need to maintain compact genomes through the use of unspliced transcripts and maintaining efficient gene expression may have shaped the evolution of herpesvirus genomes, leading to characteristic CpG dinucleotide patterns.
Topics: Alphaherpesvirinae; Animals; Betaherpesvirinae; Dinucleoside Phosphates; Evolution, Molecular; Gammaherpesvirinae; Gene Expression; Genome, Viral; Herpesviridae; Host-Pathogen Interactions; Humans; Interferons; RNA Splicing; RNA, Viral; RNA-Binding Proteins; Signal Transduction; Viral Proteins
PubMed: 34578438
DOI: 10.3390/v13091857 -
Viruses Nov 2020Herpes simplex viruses (HSVs) are neurotropic viruses with broad host range whose infections cause considerable health problems in both animals and humans. In fact, 67%... (Review)
Review
Herpes simplex viruses (HSVs) are neurotropic viruses with broad host range whose infections cause considerable health problems in both animals and humans. In fact, 67% of the global population under the age of 50 are infected with HSV-1 and 13% have clinically recurrent HSV-2 infections. The most prescribed antiherpetics are nucleoside analogues such as acyclovir, but the emergence of mutants resistant to these drugs and the lack of available vaccines against human HSVs has led to an imminent need for new antivirals. Valproic acid (VPA) is a branched short-chain fatty acid clinically used as a broad-spectrum antiepileptic drug in the treatment of neurological disorders, which has shown promising antiviral activity against some herpesviruses. Moreover, its amidic derivatives valpromide and valnoctamide also share this antiherpetic activity. This review summarizes the current research on the use of VPA and its amidic derivatives as alternatives to traditional antiherpetics in the fight against HSV infections.
Topics: Alphaherpesvirinae; Amides; Animals; Antiviral Agents; Dose-Response Relationship, Drug; Humans; Microbial Sensitivity Tests; Molecular Structure; Valproic Acid
PubMed: 33256172
DOI: 10.3390/v12121356 -
Antimicrobial Agents and Chemotherapy Mar 2021Herpesviruses are widespread and can cause serious illness. Many currently available antiviral drugs have limited effects, result in rapid development of resistance, and...
Herpesviruses are widespread and can cause serious illness. Many currently available antiviral drugs have limited effects, result in rapid development of resistance, and often exhibit dose-dependent toxicity. Especially for human cytomegalovirus (HCMV), new well-tolerated compounds with novel mechanisms of action are urgently needed. In this study, we characterized the antiviral activity of two new diazadispiroalkane derivatives, 11826091 and 11826236. These two small molecules exhibited strong activity against low-passage-number HCMV. Pretreatment of cell-free virus with these compounds greatly reduced infection. Time-of-addition assays where 11826091 or 11826236 was added to cells before infection, before and during infection, or during or after infection demonstrated an inhibitory effect on early steps of infection. Interestingly, 11826236 had an effect by addition to cells after infection. Results from entry assays showed the major effect to be on attachment. Only 11826236 had a minimal effect on penetration comparable to heparin. Further, no effect on virus infection was found for cell lines with a defect in heparan sulfate expression or lacking all surface glycosaminoglycans, indicating that these small molecules bind to heparan sulfate on the cell surface. To test this further, we extended our analyses to pseudorabies virus (PrV), a member of the , which is known to use cell surface heparan sulfate for initial attachment via nonessential glycoprotein C (gC). While infection with PrV wild type was strongly impaired by 11826091 or 11826236, as with heparin, a mutant lacking gC was unaffected by either treatment, demonstrating that primary attachment to heparan sulfate via gC is targeted by these small molecules.
Topics: Alkanes; Animals; Antiviral Agents; Glycosaminoglycans; Heparin; Heparitin Sulfate; Herpesvirus 1, Suid; Humans; Spiro Compounds; Viral Envelope Proteins; Virus Internalization
PubMed: 33495228
DOI: 10.1128/AAC.02103-20 -
Frontiers in Immunology 2021In the process of infecting the host, alphaherpesviruses have derived a series of adaptation and survival strategies, such as latent infection, autophagy and immune... (Review)
Review
In the process of infecting the host, alphaherpesviruses have derived a series of adaptation and survival strategies, such as latent infection, autophagy and immune evasion, to survive in the host environment. Infected cell protein 22 (ICP22) or its homologue immediate early protein 63 (IE63) is a posttranslationally modified multifunctional viral regulatory protein encoded by all alphaherpesviruses. In addition to playing an important role in the efficient use of host cell RNA polymerase II, it also plays an important role in the defense process of the virus overcoming the host immune system. These two effects of ICP22/IE63 are important survival strategies for alphaherpesviruses. In this review, we summarize the complex mechanism by which the ICP22 protein regulates the transcription of alphaherpesviruses and their host genes and the mechanism by which ICP22/IE63 participates in immune escape. Reviewing these mechanisms will also help us understand the pathogenesis of alphaherpesvirus infections and provide new strategies to combat these viral infections.
Topics: Alphaherpesvirinae; Animals; Gene Expression Regulation, Viral; Herpesviridae Infections; Humans; Immediate-Early Proteins; Immune Evasion
PubMed: 34925320
DOI: 10.3389/fimmu.2021.743466 -
Trends in Microbiology Dec 2012After replicating in surface epithelia, herpes simplex virus type-1 (HSV-1) enters the axonal terminals of peripheral neurons. The viral genome translocates to the... (Review)
Review
After replicating in surface epithelia, herpes simplex virus type-1 (HSV-1) enters the axonal terminals of peripheral neurons. The viral genome translocates to the nucleus, where it establishes a specialized infection known as latency, re-emerging periodically to seed new infections. Studies using cultured neuron models that faithfully recapitulate the molecular hallmarks of latency and reactivation defined in live animal models have provided fresh insight into the control of latency and connections to neuronal physiology. With this comes a growing appreciation for how the life cycles of HSV-1 and other herpesviruses are governed by key host pathways controlling metabolic homeostasis and cell identity.
Topics: Animals; Herpesvirus 1, Human; Humans; Neurons; Virus Activation; Virus Latency
PubMed: 22963857
DOI: 10.1016/j.tim.2012.08.005 -
Clinical Microbiology Reviews Jul 1997The clinical manifestations of herpes simplex virus infection generally involve a mild and localized primary infection followed by asymptomatic (latent) infection... (Review)
Review
The clinical manifestations of herpes simplex virus infection generally involve a mild and localized primary infection followed by asymptomatic (latent) infection interrupted sporadically by periods of recrudescence (reactivation) where virus replication and associated cytopathologic findings are manifest at the site of initial infection. During the latent phase of infection, viral genomes, but not infectious virus itself, can be detected in sensory and autonomic neurons. The process of latent infection and reactivation has been subject to continuing investigation in animal models and, more recently, in cultured cells. The initiation and maintenance of latent infection in neurons are apparently passive phenomena in that no virus gene products need be expressed or are required. Despite this, a single latency-associated transcript (LAT) encoded by DNA encompassing about 6% of the viral genome is expressed during latent infection in a minority of neurons containing viral DNA. This transcript is spliced, and the intron derived from this splicing is stably maintained in the nucleus of neurons expressing it. Reactivation, which can be induced by stress and assayed in several animal models, is facilitated by the expression of LAT. Although the mechanism of action of LAT-mediated facilitation of reactivation is not clear, all available evidence argues against its involving the expression of a protein. Rather, the most consistent models of action involve LAT expression playing a cis-acting role in a very early stage of the reactivation process.
Topics: Animals; Disease Models, Animal; Encephalitis; Gene Expression Regulation, Viral; Herpes Simplex; Herpesvirus 3, Human; Humans; In Situ Hybridization, Fluorescence; Mice; Neurons; Promoter Regions, Genetic; Rabbits; Simplexvirus; Virus Activation; Virus Latency
PubMed: 9227860
DOI: 10.1128/CMR.10.3.419 -
Viruses Aug 2021The alphaherpesviruses are pathogens of the mammalian nervous system. Initial infection is commonly at mucosal epithelia, followed by spread to, and establishment of... (Review)
Review
The alphaherpesviruses are pathogens of the mammalian nervous system. Initial infection is commonly at mucosal epithelia, followed by spread to, and establishment of latency in, the peripheral nervous system. During productive infection, viral gene expression, replication of the dsDNA genome, capsid assembly and genome packaging take place in the infected cell nucleus, after which mature nucleocapsids emerge into the cytoplasm. Capsids must then travel to their site of envelopment at cytoplasmic organelles, and enveloped virions need to reach the cell surface for release and spread. Transport at each of these steps requires movement of alphaherpesvirus particles through a crowded and viscous cytoplasm, and for distances ranging from several microns in epithelial cells, to millimeters or even meters during egress from neurons. To solve this challenging problem alphaherpesviruses, and their assembly intermediates, exploit microtubule- and actin-dependent cellular motors. This review focuses upon the mechanisms used by alphaherpesviruses to recruit kinesin, myosin and dynein motors during assembly and egress.
Topics: Actins; Alphaherpesvirinae; Capsid; Dyneins; Host Microbial Interactions; Humans; Kinesins; Microtubules; Myosins; Virion; Virus Assembly; Virus Release
PubMed: 34452486
DOI: 10.3390/v13081622