Herpes Simplex Virus Type 1 Amplicon Vectors with Glucocorticoid-Inducible Gene Expression

ABSTRACT Herpes simplex virus type 1 (HSV-1) mutants that fail to express the viral immediate-early protein ICP0 have a pronounced defect in viral gene expression and plaque formation in limited-passage human fibroblasts. ICP0 is a RING finger E3 ubiquitin ligase that induces the degradation of several cellular proteins. PML, the organizer of cellular nuclear substructures known as PML nuclear bodies or ND10, is one of the most notable proteins that is targeted by ICP0. Depletion of PML from human fibroblasts increases ICP0-null mutant HSV-1 gene expression, but not to wild-type levels. In this study, we report that depletion of Sp100, another major ND10 protein, results in a similar increase in ICP0-null mutant gene expression and that simultaneous depletion of both proteins complements the mutant virus to a greater degree. Although chromatin assembly and modification undoubtedly play major roles in the regulation of HSV-1 infection, we found that inhibition of histone deacetylase activity with trichostatin A was unable to complement the defect of ICP0-null mutant HSV-1 in either normal or PML-depleted human fibroblasts. These data lend further weight to the hypothesis that ND10 play an important role in the regulation of HSV-1 gene expression.

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Optimal Gene Expression for Efficient Replication of Herpes Simplex Virus Type 1 (HSV-1)

Herpesviridae - A Look Into This Unique Family of Viruses ◽

10.5772/19568 ◽

2012 ◽

Author(s):

Jun Nakabayashi

Keyword(s):

Gene Expression ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Virus Type ◽

Herpes Simplex Virus Type ◽

Efficient Replication ◽

Simplex Virus ◽

Hsv 1

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Specific Histone Tail Modification and Not DNA Methylation Is a Determinant of Herpes Simplex Virus Type 1 Latent Gene Expression

Journal of Virology ◽

10.1128/jvi.78.3.1139-1149.2004 ◽

2004 ◽

Vol 78 (3) ◽

pp. 1139-1149 ◽

Cited By ~ 109

Author(s):

Nicole J. Kubat ◽

Robert K. Tran ◽

Peterjon McAnany ◽

David C. Bloom

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Virus Type ◽

Herpes Simplex Virus Type ◽

Epigenetic Mechanism ◽

Simplex Virus ◽

Hsv 1

ABSTRACT During herpes simplex virus type 1 (HSV-1) latency, gene expression is tightly repressed except for the latency-associated transcript (LAT). The mechanistic basis for this repression is unknown, but its global nature suggests regulation by an epigenetic mechanism such as DNA methylation. Previous work demonstrated that latent HSV-1 genomes are not extensively methylated, but these studies lacked the resolution to examine methylation of individual CpGs that could repress transcription from individual promoters during latency. To address this point, we employed established models to predict genomic regions with the highest probability of being methylated and, using bisulfite sequencing, analyzed the methylation profiles of these regions. We found no significant methylation of latent DNA isolated from mouse dorsal root ganglia in any of the regions examined, including the ICP4 and LAT promoters. This analysis indicates that methylation is unlikely to play a major role in regulating HSV-1 latent gene expression. Subsequently we focused on differential histone modification as another epigenetic mechanism that could regulate latent transcription. Chromatin immunoprecipitation analysis of the latent HSV-1 DNA repeat regions demonstrated that a portion of the LAT region is associated with histone H3 acetylated at lysines 9 and 14, consistent with a euchromatic and nonrepressed structure. In contrast, the chromatin associated with the HSV-1 DNA polymerase gene located in the unique long segment was not enriched in H3 acetylated at lysines 9 and 14, suggesting a transcriptionally inactive structure. These data suggest that histone composition may be a major regulatory determinant of HSV latency.

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Activation of cellular interferon-responsive genes after infection of human cells with herpes simplex virus type 1

Journal of General Virology ◽

10.1099/0022-1317-81-9-2215 ◽

2000 ◽

Vol 81 (9) ◽

pp. 2215-2218 ◽

Cited By ~ 96

Author(s):

Mary Jane Nicholl ◽

Laurence H. Robinson ◽

Chris M. Preston

Keyword(s):

Gene Expression ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Virus Type ◽

Herpes Simplex Virus Type ◽

Human Fibroblasts ◽

Interferon Α ◽

Simplex Virus ◽

Hsv 1

Previous studies have shown that infection of human fibroblasts with human cytomegalovirus (HCMV) results in activation of cellular interferon-responsive gene expression. We demonstrate here that infection of human fibroblasts with herpes simplex virus type 1 (HSV-1) in the absence of de novo protein synthesis also induces the expression of interferon-responsive genes. Five genes tested (encoding ISG54, IFI56, ISG15, 9-27 and MxA) were activated by infection with HSV-1, although the degree of response varied between the individual genes. HSV-1 was a less efficient inducer than HCMV. The effect was a consequence of binding of the virus particle to the cell surface or of the presence of virion components within the infected cell. Induction was mediated by a pathway other than the mechanism through which interferon-α mediates its effects on cellular gene expression.

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Expression of the herpes simplex virus type 1 latency-associated transcripts does not influence latency establishment of virus mutants deficient for neuronal replication

Journal of General Virology ◽

10.1099/vir.0.056176-0 ◽

2013 ◽

Vol 94 (11) ◽

pp. 2489-2494 ◽

Cited By ~ 3

Author(s):

M. P. Nicoll ◽

S. Efstathiou

Keyword(s):

Gene Expression ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Virus Type ◽

Herpes Simplex Virus Type ◽

Viral Gene ◽

Peripheral Tissues ◽

Lytic Gene ◽

Simplex Virus

Herpes simplex virus type 1 establishes latency within neurons of the trigeminal ganglion. During latency, viral gene expression is largely restricted to the latency-associated transcripts (LATs), which, whilst not essential for any aspect of latency, function to suppress lytic gene expression and enhance the survival of virus-infected neurons. The latent cell population comprises primary-order neurons infected directly from peripheral tissues and cells infected following further virus spread within the ganglion. In order to assess the role of LAT expression on latency establishment within first-order neurons, we infected ROSA26R reporter mice with Cre recombinase-expressing recombinant viruses harbouring deletion of the thymidine kinase lytic gene and/or the core LAT promoter. We found that LAT expression did not impact on latency establishment in viruses unable to replicate in neurons, and under these conditions, it was not required for the survival of neurons between 3 and 31 days post-infection.

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Analysis in Cos-1 cells of processing and polyadenylation signals by using derivatives of the herpes simplex virus type 1 thymidine kinase gene.

Molecular and Cellular Biology ◽

10.1128/mcb.3.2.267 ◽

1983 ◽

Vol 3 (2) ◽

pp. 267-279 ◽

Cited By ~ 13

Author(s):

C N Cole ◽

G M Santangelo

Keyword(s):

Gene Expression ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Thymidine Kinase ◽

Virus Type ◽

Herpes Simplex Virus Type ◽

Polyoma Virus ◽

Simplex Virus ◽

Polyadenylation Signals

Bal31 nuclease was used to resect the herpes simplex virus type 1 thymidine kinase (tk) gene from its 3' end, and a plasmid, pTK206, was isolated that lacked the processing and polyadenylation signals normally found at the 3' end of the gene. The wild-type gene, pTK2, and pTK206 were each transferred to pSV010, a plasmid containing the simian virus 40 (SV40) origin of DNA replication, allowing replication and analysis of the patterns of transcription in Cos-1 cells. Fragments of DNA containing processing and polyadenylation signals from SV40 and polyoma virus were inserted into the 3' end of the resected tk gene, pTK206. We found that tk gene expression requires a processing and polyadenylation signal, that signals from SV40 and polyoma virus could substitute for the herpes simplex virus tk signal, and that considerable differences in the levels of tk mRNA were present in Cos-1 cells transfected by these gene constructs. In addition, tk gene expression was restored to a low level after the insertion of an 88-base-pair fragment from the middle of the SV40 early region. Processing and polyadenylation do not occur in the vicinity of this fragment in SV40, even though it contains the hexanucleotide 5'-AAUAAA-3'.

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