scholarly journals Dynamic Response of IFI16 and Promyelocytic Leukemia Nuclear Body Components to Herpes Simplex Virus 1 Infection

2015 ◽  
Vol 90 (1) ◽  
pp. 167-179 ◽  
Author(s):  
Roger D. Everett
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Genome ◽  
Viral Gene Expression ◽  
Nuclear Body ◽  
Viral Gene ◽  
Intrinsic Resistance ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACTIntrinsic immunity is an aspect of antiviral defense that operates through diverse mechanisms at the intracellular level through a wide range of constitutively expressed cellular proteins. In the case of herpesviruses, intrinsic resistance involves the repression of viral gene expression during the very early stages of infection, a process that is normally overcome by viral tegument and/or immediate-early proteins. Thus, the balance between cellular repressors and virus-counteracting proteins determines whether or not a cell becomes productively infected. One aspect of intrinsic resistance to herpes simplex virus 1 (HSV-1) is conferred by components of promyelocytic leukemia nuclear bodies (PML NBs), which respond to infection by accumulating at sites that are closely associated with the incoming parental HSV-1 genomes. Other cellular proteins, including IFI16, which has been implicated in sensing pathogen DNA and initiating signaling pathways that lead to an interferon response, also respond to viral genomes in this manner. Here, studies of the dynamics of the response of PML NB components and IFI16 to invading HSV-1 genomes demonstrated that this response is extremely rapid, occurring within the first hour after addition of the virus, and that human Daxx (hDaxx) and IFI16 respond more rapidly than PML. In the absence of HSV-1 regulatory protein ICP0, which counteracts the recruitment process, the newly formed, viral-genome-induced PML NB-like foci can fuse with existing PML NBs. These data are consistent with a model involving viral genome sequestration into such structures, thereby contributing to the low probability of initiation of lytic infection in the absence of ICP0.IMPORTANCEHerpesviruses have intimate interactions with their hosts, with infection leading either to the productive lytic cycle or to a quiescent infection in which viral gene expression is suppressed while the viral genome is maintained in the host cell nucleus. Whether a cell becomes lytically or quiescently infected can be determined through the competing activities of cellular repressors and viral activators, some of which counteract cell-mediated repression. Therefore, the events that occur within the earliest stages of infection can be of crucial importance. This paper describes the extremely rapid response to herpes simplex virus 1 infection of cellular protein IFI16, a sensor of pathogen DNA, and also of the PML nuclear body proteins PML and hDaxx, as revealed by live-cell microscopy. The data imply that these proteins can accumulate on or close to the viral genomes in a sequential manner which may lead to their sequestration and repression.

scholarly journals Regulation of viral gene expression by the herpes simplex virus 1 UL24 protein (HSV-1 UL24 inhibits accumulation of viral transcripts)

Virology ◽  
2016 ◽  
Vol 495 ◽  
pp. 148-160 ◽  
Author(s):  
Carolina Sanabria-Solano ◽  
Carmen Elena Gonzalez ◽  
Nicolas Richerioux ◽  
Luc Bertrand ◽  
Slimane Dridi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1

scholarly journals RNA Polymerase II Promoter-Proximal Pausing and Release to Elongation Are Key Steps Regulating Herpes Simplex Virus 1 Transcription

2019 ◽  
Vol 94 (5) ◽  
Author(s):  
Claire H. Birkenheuer ◽  
Joel D. Baines
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Rna Polymerase Ii ◽  
Viral Genome ◽  
Viral Dna ◽  
Herpes Simplex Virus 1 ◽  
Pol Ii ◽  
Late Genes ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT Herpes simplex virus 1 (HSV-1) genes are transcribed by cellular RNA polymerase II (Pol II). Expression of viral immediate early (α) genes is followed sequentially by early (β), late (γ1), and true late (γ2) genes. We used precision nuclear run-on with deep sequencing to map and to quantify Pol II on the HSV-1(F) genome with single-nucleotide resolution. Approximately 30% of total Pol II relocated to viral genomes within 3 h postinfection (hpi), when it occupied genes of all temporal classes. At that time, Pol II on α genes accumulated most heavily at promoter-proximal pause (PPP) sites located ∼60 nucleotides downstream of the transcriptional start site, while β genes bore Pol II more evenly across gene bodies. At 6 hpi, Pol II increased on γ1 and γ2 genes while Pol II pausing remained prominent on α genes. At that time, average cytoplasmic mRNA expression from α and β genes decreased, relative to levels at 3 hpi, while γ1 relative expression increased slightly and γ2 expression increased more substantially. Cycloheximide treatment during the first 3 h reduced the amount of Pol II associated with the viral genome and confined most of the remaining Pol II to α gene PPP sites. Inhibition of both cyclin-dependent kinase 9 activity and viral DNA replication reduced Pol II on the viral genome and restricted much of the remaining Pol II to PPP sites. IMPORTANCE These data suggest that viral transcription is regulated not only by Pol II recruitment to viral genes but also by control of elongation into viral gene bodies. We provide a detailed map of Pol II occupancy on the HSV-1 genome that clarifies features of the viral transcriptome, including the first identification of Pol II PPP sites. The data indicate that Pol II is recruited to late genes early in infection. Comparing α and β gene occupancy at PPP sites and gene bodies suggests that Pol II is released more efficiently into the bodies of β genes than α genes at 3 hpi and that repression of α gene expression late in infection is mediated by prolonged promoter-proximal pausing. In addition, DNA replication is required to maintain full Pol II occupancy on viral DNA and to promote elongation on late genes later in infection.

scholarly journals Herpes Simplex Virus Latency Is Noisier the Closer We Look

2019 ◽  
Vol 94 (4) ◽  
Author(s):  
Navneet Singh ◽  
David C. Tscharke
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Genome ◽  
Infectious Virus ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Peripheral Neurons ◽  
Virus Latency ◽  
Simplex Virus

ABSTRACT During herpes simplex virus (HSV) latency, the viral genome is harbored in peripheral neurons in the absence of infectious virus but with the potential to restart infection. Advances in epigenetics have helped explain how viral gene expression is largely inhibited during latency. Paradoxically, at the same time, the view that latency is entirely silent has been eroding. This low-level noise has implications for our understanding of HSV latency and should not be ignored.

Chicken ovalbumin gene fused to a herpes simplex virus alpha promoter and linked to a thymidine kinase gene is regulated like a viral gene

1982 ◽  
Vol 2 (3) ◽  
pp. 233-240
Author(s):  
L E Post ◽  
B Norrild ◽  
T Simpson ◽  
B Roizman
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Extracellular Fluid ◽  
Regulatory Elements ◽  
Viral Gene ◽  
Herpes Simplex Virus 1 ◽  
Kinase Gene ◽  
Covalently Linked ◽  
Simplex Virus ◽  
Hsv 1

We are describing a system for the introduction, selection, and expression of eucaryotic genes in higher eucaryotic cells. The carrier consisted of the herpes simplex virus 1 (HSV-1) tk gene covalently linked to an HSV-1 alpha promoter directed away from the tk gene. In this study we fused to the alpha promoter the 5' transcribed noncoding sequences and the coding sequences of the chicken oviduct ovalbumin gene. Cells converted to the TK+ phenotype with this chimeric fragment produced an ovalbumin precursor which was processed and secreted into the extracellular fluid. The ovalbumin gene utilized the HSV-1 alpha promoter and was regulated as a viral gene inasmuch as inversion of the genomic DNA relative to the alpha promoter resulted in no ovalbumin synthesis, and production of ovalbumin was enhanced after superinfection with HSV-1. Synthesis of ovalbumin was not detected when cDNA was linked to the HSV-1 alpha promoter. The carrier system described in this study is suitable for introduction, selection, and expression of eucaryotic genes whose natural promoter is either weak or requires the presence of regulatory elements which may be absent from undifferentiated cells in culture.

scholarly journals The latency-associated transcript locus of herpes simplex virus 1 is a virulence determinant in human skin

2020 ◽  
Vol 16 (12) ◽  
pp. e1009166
Author(s):  
Emilia A. H. Vanni ◽  
Joseph W. Foley ◽  
Andrew J. Davison ◽  
Marvin Sommer ◽  
Dongmei Liu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Human Skin ◽  
Lytic Infection ◽  
Growth Defect ◽  
Viral Gene ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1

Herpes simplex virus 1 (HSV-1) infects skin and mucosal epithelial cells and then travels along axons to establish latency in the neurones of sensory ganglia. Although viral gene expression is restricted during latency, the latency-associated transcript (LAT) locus encodes many RNAs, including a 2 kb intron known as the hallmark of HSV-1 latency. Here, we studied HSV-1 infection and the role of the LAT locus in human skin xenografts in vivo and in cultured explants. We sequenced the genomes of our stock of HSV-1 strain 17syn+ and seven derived viruses and found nonsynonymous mutations in many viral proteins that had no impact on skin infection. In contrast, deletions in the LAT locus severely impaired HSV-1 replication and lesion formation in skin. However, skin replication was not affected by impaired intron splicing. Moreover, although the LAT locus has been implicated in regulating gene expression in neurones, we observed only small changes in transcript levels that were unrelated to the growth defect in skin, suggesting that its functions in skin may be different from those in neurones. Thus, although the LAT locus was previously thought to be dispensable for lytic infection, we show that it is a determinant of HSV-1 virulence during lytic infection of human skin.

scholarly journals Herpes Simplex Virus VP16, but Not ICP0, Is Required To Reduce Histone Occupancy and Enhance Histone Acetylation on Viral Genomes in U2OS Osteosarcoma Cells

2009 ◽  
Vol 84 (3) ◽  
pp. 1366-1375 ◽  
Author(s):  
Meaghan H. Hancock ◽  
Anna R. Cliffe ◽  
David M. Knipe ◽  
James R. Smiley
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Chromatin Structure ◽  
Viral Genome ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Osteosarcoma Cell ◽  
U2os Cells ◽  
Simplex Virus

ABSTRACT The herpes simplex virus (HSV) genome rapidly becomes associated with histones after injection into the host cell nucleus. The viral proteins ICP0 and VP16 are required for efficient viral gene expression and have been implicated in reducing the levels of underacetylated histones on the viral genome, raising the possibility that high levels of underacetylated histones inhibit viral gene expression. The U2OS osteosarcoma cell line is permissive for replication of ICP0 and VP16 mutants and appears to lack an innate antiviral repression mechanism present in other cell types. We therefore used chromatin immunoprecipitation to determine whether U2OS cells are competent to load histones onto HSV DNA and, if so, whether ICP0 and/or VP16 are required to reduce histone occupancy and enhance acetylation in this cell type. High levels of underacetylated histone H3 accumulated at several locations on the viral genome in the absence of VP16 activation function; in contrast, an ICP0 mutant displayed markedly reduced histone levels and enhanced acetylation, similar to wild-type HSV. These results demonstrate that U2OS cells are competent to load underacetylated histones onto HSV DNA and uncover an unexpected role for VP16 in modulating chromatin structure at viral early and late loci. One interpretation of these findings is that ICP0 and VP16 affect viral chromatin structure through separate pathways, and the pathway targeted by ICP0 is defective in U2OS cells. We also show that HSV infection results in decreased histone levels on some actively transcribed genes within the cellular genome, demonstrating that viral infection alters cellular chromatin structure.

scholarly journals Promoting Simultaneous Onset of Viral Gene Expression Among Cells Infected with Herpes Simplex Virus-1

2017 ◽  
Vol 8 ◽  
Author(s):  
Maya Ralph ◽  
Marina Bednarchik ◽  
Enosh Tomer ◽  
Dor Rafael ◽  
Sefi Zargarian ◽  
...  
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus

scholarly journals Linker Histones Are Mobilized during Infection with Herpes Simplex Virus Type 1

2008 ◽  
Vol 82 (17) ◽  
pp. 8629-8646 ◽  
Author(s):  
Kristen L. Conn ◽  
Michael J. Hendzel ◽  
Luis M. Schang
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Virus Type ◽  
Herpes Simplex Virus Type ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Genome Replication ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT Histones interact with herpes simplex virus type 1 (HSV-1) genomes and localize to replication compartments early during infections. However, HSV-1 genomes do not interact with histones in virions and are deposited in nuclear domains devoid of histones. Moreover, late viral replication compartments are also devoid of histones. The processes whereby histones come to interact with HSV-1 genomes, to be later displaced, remain unknown. However, they would involve the early movement of histones to the domains containing HSV-1 genomes and the later movement away from them. Histones unbind from chromatin, diffuse through the nucleoplasm, and rebind at different sites. Such mobility is upregulated by, for example, phosphorylation or acetylation. We evaluated whether HSV-1 infection modulates histone mobility, using fluorescence recovery after photobleaching. All somatic H1 variants were mobilized to different degrees. H1.2, the most mobilized, was mobilized at 4 h and further so at 7 h after infection, resulting in increases in its “free” pools. H1.2 was mobilized to a “basal” degree under conditions of little to no HSV-1 protein expression. This basal mobilization required nuclear native HSV-1 genomes but was independent of HSV-1 proteins and most likely due to cellular responses. Mobilization above this basal degree, and increases in H1.2 free pools, however, depended on immediate-early or early HSV-1 proteins, but not on HSV-1 genome replication or late proteins. Linker histone mobilization is a novel consequence of cell-virus interactions, which is consistent with the dynamic interactions between histones and HSV-1 genomes during lytic infection; it may also participate in the regulation of viral gene expression.

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