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Shrivastava R, Upreti RK, Chaturvedi UC. Effects of dengue virus infection on the spleen of male mice given hexavalent chromium with drinking water. Toxicol Mech Methods 2012; 15:323-9. [PMID: 20021051 DOI: 10.1080/153765291009732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The present study was undertaken to investigate the effects of dengue virus (DV) infection in male mice given drinking water containing 250 ppm Cr (VI) and the normal control male mice given plain water to drink. On the basis of intake of water in 24 h, the average dose of Cr (VI) in each mouse was 14.8 mg/kg. After 3, 6, and 9 weeks of drinking Cr (VI), a set of five mice from each group were inoculated intracerebrally (ic) with a 1000 x LD(50) (100 times the lethal dose that kills 50% mice) dose of DV, and the effects on the spleen were studied at the fourth and eightth day postinoculation. It was observed that Cr (VI) drinking and DV infection led to reduction in the weight of the spleen, but the peak reduction was seen in Cr (VI)-fed mice infected with DV, being 30, 34, and 61% at 3, 6, and 9 weeks respectively. A similar response was seen with respect to the cytotoxic activity of spleen homogenates, phagocytic activity of macrophages, and the mitogenic response of spleen cells to concanavalin A from different groups of animals, being most marked (58 to 60%) at the ninth week of Cr (VI) drinking. This shows a summation of adverse effects of DV infection in mice preexposed to Cr (VI).
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Affiliation(s)
- Richa Shrivastava
- Biomembrane Division, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow, 226001India
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2
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Thompson RL, Preston CM, Sawtell NM. De novo synthesis of VP16 coordinates the exit from HSV latency in vivo. PLoS Pathog 2009; 5:e1000352. [PMID: 19325890 PMCID: PMC2654966 DOI: 10.1371/journal.ppat.1000352] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Accepted: 02/26/2009] [Indexed: 12/26/2022] Open
Abstract
The mechanism controlling the exit from herpes simplex virus latency (HSV) is of
central importance to recurrent disease and transmission of infection, yet
interactions between host and viral functions that govern this process remain
unclear. The cascade of HSV gene transcription is initiated by the
multifunctional virion protein VP16, which is expressed late in the viral
replication cycle. Currently, it is widely accepted that VP16 transactivating
function is not involved in the exit from latency. Utilizing the mouse ocular
model of HSV pathogenesis together with genetically engineered viral mutants and
assays to quantify latency and the exit from latency at the single neuron level,
we show that in vivo (i) the VP16 promoter confers distinct regulation critical
for viral replication in the trigeminal ganglion (TG) during the acute phase of
infection and (ii) the transactivation function of VP16 (VP16TF) is uniquely
required for the exit from latency. TG neurons latently infected with the VP16TF
mutant in1814 do not express detectable viral proteins following stress, whereas
viruses with mutations in the other major viral transcription regulators ICP0
and ICP4 do exit the latent state. Analysis of a VP16 promoter/reporter mutant
in the background of in1814 demonstrates that the VP16 promoter is activated in
latently infected neurons following stress in the absence of other viral
proteins. These findings support the novel hypothesis that de novo expression of
VP16 regulates entry into the lytic program in neurons at all phases of the
viral life cycle. HSV reactivation from latency conforms to a model in which
stochastic derepression of the VP16 promoter and expression of VP16 initiates
entry into the lytic cycle. Herpes simplex virus (HSV) establishes life-long latent infections in sensory
neurons of the human host. Periodically, HSV exits latency in an infected neuron
and is transported to the body surface where it replicates, leading to recurrent
disease and infection of new hosts. We do not currently understand how entry
into the lytic cycle is blocked in neurons and latency is established. Nor do we
know how, at some time in the future, the lytic program becomes activated in the
one or two latently infected neurons which characterize a reactivation event. In
tissue culture cells, and by analogy in cells at the body surface, the HSV
replication program is initiated by the interaction of a virion protein, VP16
(brought in with the virus as a protein), with host cell factors. Here we show
that the de novo synthesis of VP16 is required for efficient viral replication
during the acute phase of infection in neurons. This indicates that latency is
favored because VP16 may not be transported efficiently to the nerve cell
nucleus. Once latency is established, the de novo expression of VP16 is an
absolute and very early requirement for the exit from the latent state. Our data
support a model of HSV reactivation in which the stochastic derepression of the
VP16 promoter and resulting expression of VP16 starts the viral lytic
program.
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Affiliation(s)
- Richard L. Thompson
- Department of Molecular Genetics, Microbiology, and Biochemistry,
University of Cincinnati School of Medicine, Cincinnati, Ohio, United States of
America
| | - Chris M. Preston
- Medical Research Council Virology Unit, Glasgow, Scotland, United
Kingdom
| | - Nancy M. Sawtell
- Department of Pediatrics, Division of Infectious Diseases, Cincinnati
Children's Hospital Medical Center, Cincinnati, Ohio, United States of
America
- * E-mail:
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Toma HS, Murina AT, Areaux RG, Neumann DM, Bhattacharjee PS, Foster TP, Kaufman HE, Hill JM. Ocular HSV-1 latency, reactivation and recurrent disease. Semin Ophthalmol 2008; 23:249-73. [PMID: 18584563 DOI: 10.1080/08820530802111085] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ocular infection with HSV-1 continues to be a serious clinical problem despite the availability of effective antivirals. Primary infection with HSV-1 can involve ocular and adenaxial sites and can manifest as blepharitis, conjunctivitis, or corneal epithelial keratitis. After initial ocular infection, HSV-1 can establish latent infection in the trigeminal ganglia for the lifetime of the host. During latency, the viral genome is retained in the neuron without producing viral proteins. However, abundant transcription occurs at the region encoding the latency-associated transcript, which may play significant roles in the maintenance of latency as well as neuronal reactivation. Many host and viral factors are involved in HSV-1 reactivation from latency. HSV-1 DNA is shed into tears and saliva of most adults, but in most cases this does not result in lesions. Recurrent disease occurs as HSV-1 is carried by anterograde transport to the original site of infection, or any other site innervated by the latently infected ganglia, and can reinfect the ocular tissues. Recurrent corneal disease can lead to corneal scarring, thinning, stromal opacity and neovascularization and, eventually, blindness. In spite of intensive antiviral and anti-inflammatory therapy, a significant percentage of patients do not respond to chemotherapy for herpetic necrotizing stromal keratitis. Therefore, the development of therapies that would reduce asymptomatic viral shedding and lower the risks of recurrent disease and transmission of the virus is key to decreasing the morbidity of ocular herpetic disease. This review will highlight basic HSV-1 virology, and will compare the animal models of latency, reactivation, and recurrent ocular disease to the current clinical data.
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Affiliation(s)
- Hassanain S Toma
- Louisiana State University Health Sciences Center, New Orleans, LA 70112-2234, USA
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4
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Clement C, Popp MP, Bloom DC, Schultz G, Liu L, Neumann DM, Bhattacharjee PS, Hill JM. Microarray analysis of host gene expression for comparison between naïve and HSV-1 latent rabbit trigeminal ganglia. Mol Vis 2008; 14:1209-21. [PMID: 18615202 PMCID: PMC2443748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 04/03/2008] [Indexed: 10/27/2022] Open
Abstract
PURPOSE To analyze the rabbit host global gene expression patterns in uninfected and herpes simplex virus type 1 (HSV-1) latent trigeminal ganglia (TG) for identification of host response-initiated transcriptional changes during the maintenance of viral latency. METHODS The corneas of eight-week-old New Zealand White rabbits were scarified and inoculated with HSV-1 strain McKrae, 5x10(5) plaque forming units/eye. Corneal infection was verified by slit-lamp examination. Prior to sacrifice at 30 days post infection, ocular swabs confirmed no infectious virus was present. TG were aseptically removed from rabbits and placed in RNA stabilization solution. Host RNA was isolated from two groups of TG, uninfected and HSV-1 latent infected, and used to create labeled cRNA. Labeled cRNA was hybridized to two new and novel custom oligonucleotide rabbit arrays, containing a total of 3,123 probes for rabbit genes. RESULTS The rabbit TG expressed approximately 80% of genes out of a total of 3,123. A one-way ANOVA performed on the log2 transformed signal ratios showed 611 genes were significantly altered (p< or =0.05) in HSV-1 latent TG. These genes, if annotated, were separated by biologic process categories. Five broad categories were most heavily represented: protein processing, carbohydrate processing, cell adhesion, apoptosis, and host defense and immune response. Sixty of the significantly altered genes were found to be altered by more than 2 fold, and five were altered by more than 4 fold. The genes altered by more than 4 fold were all upregulated and related to host defense and immune response. Viral latency had a large effect on protein processing. Of the differentially expressed genes with an assigned biologic process, 90/349 (25.7%) were associated with protein processing. The next most populated categories were carbohydrate metabolism 39/349 (11.1%) and host defense and immune response 17/349 (4.9%). CONCLUSIONS The results of this microarray study demonstrate that host gene expression is altered in the HSV-1 latent rabbit TG. The shift in molecular processes at a pathway level reveals the presence of potential therapeutic significance inherent in the maintenance of HSV-1 latency. This is the first large-scale rabbit gene expression study, using microarray analysis, that documents the involvement of host immunity in maintaining HSV-1 latency.
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Affiliation(s)
| | | | - David C. Bloom
- Department of Molecular Genetics and Microbiology, Gainesville, FL,Department of Ophthalmology, University of Florida College of Medicine, Gainesville, FL
| | - Gregory Schultz
- Department of Ophthalmology, University of Florida College of Medicine, Gainesville, FL,University of Florida Interdisciplinary Center for Biotechnology Research, Gainesville, FL
| | - Li Liu
- Department of Obstetrics and Gynecology, Gainesville, FL,University of Florida Interdisciplinary Center for Biotechnology Research, Gainesville, FL
| | | | | | - James M. Hill
- Department of Ophthalmology, New Orleans, LA,Departments of Pharmacology, Microbiology and Neuroscience Center, Louisiana State University Health Sciences Center, New Orleans, LA
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5
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Kent JR, Fraser NW. The cellular response to herpes simplex virus type 1 (HSV-1) during latency and reactivation. J Neurovirol 2005; 11:376-83. [PMID: 16162480 DOI: 10.1080/13550280591002405] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In order to learn more about the cellular response to viral gene activity during latency and reactivation of herpes simplex virus type 1 (HSV-1), the authors have employed microarray analysis. On an array of about 1200 cellular genes, approximately 56 genes were found to be differentially regulated in infected trigeminal ganglia of mice, compared to uninfected mice, during latency and reactivation. Of these genes, 10 were examined more closely using quantitative real-time polymerase chain reaction (PCR) to confirm the microarray results. Genes involved in interferon and other signaling pathways appeared to predominate in response to a latent or reactivating HSV infection. Interestingly, some genes found to be differentially regulated in latently infected ganglia are neuronal-specific genes (pro-opiomelanocortinin; zinc finger proteins of the cerebellum 1 and 2). During reactivation, the involvement of several cell signaling molecules that may be important for the initiation of an HSV infection was observed, including various receptors and molecules involved in cell-cell spread.
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Affiliation(s)
- J R Kent
- Department of Microbiology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania 19104, USA
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6
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Sawtell NM. Quantitative analysis of herpes simplex virus reactivation in vivo demonstrates that reactivation in the nervous system is not inhibited at early times postinoculation. J Virol 2003; 77:4127-38. [PMID: 12634371 PMCID: PMC150616 DOI: 10.1128/jvi.77.7.4127-4138.2003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent studies utilizing an ex vivo mouse model of herpes simplex virus (HSV) reactivation have led to the hypothesis that, under physiologic conditions inducing viral reactivation, the immune cells within the infected ganglion block the viral replication cycle and maintain the viral genome in a latent state. One prediction from the ex vivo study is that reactivation in ganglia in vivo would be inhibited at early times postinoculation, when the numbers of inflammatory cells in the ganglia are greatest. To distinguish between an effect of the immune infiltrates on (i) infectious virus produced and/or recovered in the ganglion and (ii) the number of neurons undergoing lytic transcriptional activity (reactivating), an assay to quantify the number of neurons expressing lytic viral protein in ganglia in vivo was developed. Infectious virus and HSV protein-positive neurons were quantified from days 9 through 240 postinoculation in latently infected trigeminal ganglia before and at 22 h after hyperthermic-stress-induced reactivation. Significant increases in the amount of virus and the number of positive neurons were detected poststress in ganglia at all times examined. Unexpectedly, the greatest levels of reactivation occurred at the times examined most proximal to inoculation. Acyclovir was utilized to stop residual acute-phase virus production, and this treatment did not reduce the level of reactivation on day 14. Thus, the virus measured after induction was a product of reactivation. These data indicate that, in contrast to observations in the ex vivo model, immune cells in the ganglia during the resolution of acute infection do not inhibit reactivation of the virus in ganglia in vivo.
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Affiliation(s)
- N M Sawtell
- Division of Infectious Diseases, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA.
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7
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Nefkens I, Negorev DG, Ishov AM, Michaelson JS, Yeh ETH, Tanguay RM, Müller WEG, Maul GG. Heat shock and Cd2+ exposure regulate PML and Daxx release from ND10 by independent mechanisms that modify the induction of heat-shock proteins 70 and 25 differently. J Cell Sci 2003; 116:513-24. [PMID: 12508112 DOI: 10.1242/jcs.00253] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nuclear domains called ND10 or PML bodies might function as nuclear depots by recruiting or releasing certain proteins. Although recruitment of proteins through interferon-induced upregulation and SUMO-1 modification level of PML had been defined, it is not known whether release of proteins is regulated and has physiological consequences. Exposure to sublethal environmental stress revealed a sequential release of ND10-associated proteins. Upon heat shock Daxx and Sp100 were released but PML remained, whereas exposure to subtoxic concentrations of CdCl(2) induced the release of ND10-associated proteins, including PML, with Sp100 remaining in a few sites. In both cases, recovery times were similar and were followed by a burst of mitotic activity. Cadmium-induced release of proteins from ND10 could be blocked by inhibiting activation of p38 MAPK or ERK1/2. By contrast, heat-shock-induced desumolation of PML and release of proteins from ND10 are unaffected by these inhibitors but can be recapitulated by overexpression of the SUMO isopeptidase SENP-1. Therefore, activation of SENP-1-like SUMO isopeptidase(s) during heat shock is not affected by these kinases. Thus, the release of ND10-associated proteins is not due to a general dispersal of nuclear domains but seems to be regulated by rapid desumolation during thermal stress and through the phosphorylation cascade of stress and mitogenic signaling pathways in the case of CdCl(2). Whether the release of certain proteins had consequences was tested for heat-shock-protein transcription and synthesis. Release of Daxx correlated with Hsp25 suppression, suggesting that Daxx normally inhibits immediate Hsp25 production. Release of PML correlated with lower production of Hsp70. These results suggest that segregation or release of PML or Daxx have differential physiological relevance during the stress response. The fact that enzymatic activation of protein release or segregation after stress modifies the heat-shock response strengthens the concept of ND10 as a regulated depot of effector proteins.
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Affiliation(s)
- Isabelle Nefkens
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA
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8
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Smith CC, Nelson J, Aurelian L, Gober M, Goswami BB. Ras-GAP binding and phosphorylation by herpes simplex virus type 2 RR1 PK (ICP10) and activation of the Ras/MEK/MAPK mitogenic pathway are required for timely onset of virus growth. J Virol 2000; 74:10417-29. [PMID: 11044086 PMCID: PMC110916 DOI: 10.1128/jvi.74.22.10417-10429.2000] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We used a herpes simplex virus type 2 (HSV-2) mutant with a deletion in the RR1 (ICP10) PK domain (ICP10DeltaPK) and an MEK inhibitor (PD98059) to examine the role of ICP10 PK in virus growth. In HSV-2-infected cells, ICP10 PK binds and phosphorylates the GTPase activating protein Ras-GAP. In vitro binding and peptide competition assays indicated that Ras-GAP N-SH2 and PH domains, respectively, bind ICP10 at phosphothreonines 117 and 141 and a WD40-like motif at positions 160 to 173. Binding and phosphorylation did not occur in cells infected with ICP10DeltaPK. GTPase activity was significantly lower in HSV-2- than in ICP10DeltaPK-infected cells. Conversely, the levels of activated Ras and mitogen-activated protein kinase (MAPK), and the expression and stabilization of the transcription factor c-Fos were significantly increased in cells infected with HSV-2 or a revertant virus [HSV-2(R)] but not with ICP10DeltaPK. PD98059 inhibited MAPK activation and induction-stabilization of c-Fos. Expression from the ICP10 promoter was increased in cells infected with HSV-2 but not with ICP10DeltaPK, and increased expression was ablated by PD98059. ICP10 DNA formed a complex with nuclear extracts from HSV-2-infected cells which was supershifted by c-Fos antibody and was not seen with extracts from ICP10DeltaPK-infected cells. Complex formation was abrogated by PD98059. Onset of HSV-2 replication was significantly delayed by PD98059 (14 h versus 2 h in untreated cells), a delay similar to that seen for ICP10DeltaPK. The data indicate that Ras-GAP phosphorylation by ICP10 PK is involved in the activation of the Ras/MEK/MAPK mitogenic pathway and c-Fos induction and stabilization. This results in increased ICP10 expression and the timely onset of HSV-2 growth.
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Affiliation(s)
- C C Smith
- Departments of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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9
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Aurelian L, Smith CC. Herpes simplex virus type 2 growth and latency reactivation by cocultivation are inhibited with antisense oligonucleotides complementary to the translation initiation site of the large subunit of ribonucleotide reductase (RR1). ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 2000; 10:77-85. [PMID: 10805158 DOI: 10.1089/oli.1.2000.10.77] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Antisense oligonucleotides complementary to the translation initiation site of the herpes simplex virus type 2 (HSV-2) large subunit of ribonucleotide reductase (RR1) were studied for their ability to inhibit RR1 expression, HSV-2 growth, and its reactivation from latently infected ganglia. The oligomers caused a significant decrease (90%-97% inhibition) in HSV-2 RR1 expression and inhibited HSV-2 growth, with IC50 and IC90 values of 0.11 and 1.0 microM, respectively. The titers of HSV-2 mutants that are respectively deleted in the PK (ICP10deltaPK) or RR (ICP10deltaRR) domains of RR1 were also significantly (500-20,000-fold) decreased, indicating that the antisense oligomers interfere with the independent contributions of the two RR1 functions (PK and RR) toward virus growth. Inhibition was sequence specific, as evidenced by the failure of a two-base mutant (RR1TImu) to inhibit protein expression and HSV-2 growth. Furthermore, the antisense oligomers inhibited HSV-2 reactivation by cocultivation of latently infected ganglia (0/8). Virus was reactivated from ganglia cultured without oligomers, in the presence of unrelated oligomers (6/8), or in the presence of the two-base mutant RR1TImu (5/8) (p < 0.007 by two-tailed Fisher exact test). HSV-2 growth was not inhibited by antisense oligonucleotides complementary to the splice junction of HSV-2 immediate-early (IE) pre-mRNA 4 and 5 (IE4,5SA) or the translation initiation site of IE mRNA 4 (IE4TI), although the respective HSV-1-specific oligomers inhibit HSV-1 growth.
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MESH Headings
- 3T3 Cells
- Animals
- Antiviral Agents/pharmacology
- Chlorocebus aethiops
- Coculture Techniques
- DNA, Complementary/genetics
- DNA, Complementary/pharmacology
- DNA, Viral/pharmacology
- Growth Inhibitors/pharmacology
- HeLa Cells
- Herpesvirus 2, Human/drug effects
- Herpesvirus 2, Human/genetics
- Herpesvirus 2, Human/growth & development
- Herpesvirus 2, Human/physiology
- Humans
- Mice
- Oligonucleotides, Antisense/pharmacology
- Peptide Chain Initiation, Translational/drug effects
- Ribonucleotide Reductases/genetics
- Ribonucleotide Reductases/metabolism
- Tumor Cells, Cultured
- Vero Cells
- Virus Activation/drug effects
- Virus Activation/genetics
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Affiliation(s)
- L Aurelian
- Department of Pharmacology and Experimental Therapeutics, School of Medicine, University of Maryland, Baltimore 21201, USA
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Sundaresan P, Hunter WD, Martuza RL, Rabkin SD. Attenuated, replication-competent herpes simplex virus type 1 mutant G207: safety evaluation in mice. J Virol 2000; 74:3832-41. [PMID: 10729157 PMCID: PMC111891 DOI: 10.1128/jvi.74.8.3832-3841.2000] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) mutants that are attenuated for neurovirulence are being used for the treatment of cancer. We have examined the safety of G207, a multimutated replication-competent HSV-1 vector, in mice. BALB/c mice inoculated intracerebrally or intracerebroventricularly with 10(7) PFU of G207 survived for over 20 weeks with no apparent symptoms of disease. In contrast, over 80% of animals inoculated intracerebrally with 1.5 x 10(3) PFU of HSV-1 wild-type strain KOS and 50% of animals inoculated intracerebroventricularly with 10(4) PFU of wild-type strain F died within 10 days. Similarly, after intrahepatic inoculation of G207 (3 x 10(7) PFU) all animals survived for over 10 weeks, whereas no animals survived for even 1 week after inoculation with 10(6) PFU of KOS. After intracerebroventricular inoculation, LacZ expression was initially observed in the cells lining the ventricles and subarachnoid space; expression decreased until almost absent within 5 days postinfection, with no apparent loss of ependymal cells. G207 DNA could be detected by PCR in the brains of mice 8 weeks after intracerebral inoculation; however, no infectious virus could be detected after 2 days. As a model for latent HSV in the brain, we used survivors of an intracerebral inoculation of HSV-1 KOS at the 50% lethal dose. Inoculation of a high dose of G207 at the same stereotactic coordinates did not result in reactivation of detectable infectious virus or symptoms of disease. We conclude that G207 is safe at or above doses that were efficacious in mouse tumor studies.
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Affiliation(s)
- P Sundaresan
- Molecular Neurosurgery Laboratory, Department of Neurosurgery, Georgetown University Medical Center, Washington, D.C. 20007, USA
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11
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Cantin E, Tanamachi B, Openshaw H. Role for gamma interferon in control of herpes simplex virus type 1 reactivation. J Virol 1999; 73:3418-23. [PMID: 10074196 PMCID: PMC104106 DOI: 10.1128/jvi.73.4.3418-3423.1999] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Observation of chronic inflammatory cells and associated high-level gamma interferon (IFN-gamma) production in ganglia during herpes simplex type 1 (HSV-1) latent infection in mice (E. M. Cantin, D. R. Hinton, J. Chen, and H. Openshaw, J. Virol. 69:4898-4905, 1995) prompted studies to determine a role of IFN-gamma in maintaining latency. Mice lacking IFN-gamma (GKO mice) or the IFN-gamma receptor (RGKO mice) were inoculated with HSV-1, and the course of the infection was compared with that in IFN-gamma-competent mice with the same genetic background (129/Sv//Ev mice). A time course study showed no significant difference in trigeminal ganglionic viral titers or the timing of establishment of latency. Spontaneous reactivation resulting in infectious virus in the ganglion did not occur during latency in any of the mice. However, 24 h after the application of hyperthermic stress to mice, HSV-1 antigens were detected in multiple neurons in the null mutant mice but in only a single neuron in the 129/Sv//Ev control mice. Mononuclear inflammatory cells clustered tightly around these reactivating neurons, and by 48 h, immunostaining was present in satellite cells as well. The incidence of hyperthermia-induced reactivation as determined by recovery of infectious virus from ganglia was significantly higher in the null mutant than in control mice: 11% in 129/Sv//Ev controls, 50% in GKO mice (P = 0.0002), and 33% in RGKO mice (P = 0.03). We concluded that IFN-gamma is not involved in the induction of reactivation but rather contributes to rapid suppression of HSV once it is reactivated.
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Affiliation(s)
- E Cantin
- Beckman Research Institute, City of Hope National Medical Center, Duarte, California 91010-3012, USA. ecantin@.coh.org
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12
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Kristie TM, Vogel JL, Sears AE. Nuclear localization of the C1 factor (host cell factor) in sensory neurons correlates with reactivation of herpes simplex virus from latency. Proc Natl Acad Sci U S A 1999; 96:1229-33. [PMID: 9990006 PMCID: PMC15445 DOI: 10.1073/pnas.96.4.1229] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
After a primary infection, herpes simplex virus is maintained in a latent state in neurons of sensory ganglia until complex stimuli reactivate viral lytic replication. Although the mechanisms governing reactivation from the latent state remain unknown, the regulated expression of the viral immediate early genes represents a critical point in this process. These genes are controlled by transcription enhancer complexes whose assembly requires and is coordinated by the cellular C1 factor (host cell factor). In contrast to other tissues, the C1 factor is not detected in the nuclei of sensory neurons. Experimental conditions that induce the reactivation of herpes simplex virus in mouse model systems result in rapid nuclear localization of the protein, indicating that the C1 factor is sequestered in these cells until reactivation signals induce a redistribution of the protein. The regulated localization suggests that C1 is a critical switch determinant of the viral lytic-latent cycle.
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Affiliation(s)
- T M Kristie
- Laboratory of Viral Diseases, National Institutes of Health, Building 4-133, 9000, Rockville Pike, Bethesda, MD 20892, USA.
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13
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Miller CS, Danaher RJ, Jacob RJ. Molecular aspects of herpes simplex virus I latency, reactivation, and recurrence. CRITICAL REVIEWS IN ORAL BIOLOGY AND MEDICINE : AN OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION OF ORAL BIOLOGISTS 1998; 9:541-62. [PMID: 9825226 DOI: 10.1177/10454411980090040901] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The application of molecular biology in the study of the pathogenesis of herpes simplex virus type 1 (HSV-1) has led to significant advances in our understanding of mechanisms that regulate virus behavior in sensory neurons and epithelial tissue. Such study has provided insight into the relationship of host and viral factors that regulate latency, reactivation, and recurrent disease. This review attempts to distill decades of information involving human, animal, and cell culture studies of HSV-1 with the goal of correlating molecular events with the clinical and laboratory behavior of the virus during latency, reactivation, and recurrent disease. The purpose of such an attempt is to acquaint the clinician/scientist with the current thinking in the field, and to provide key references upon which current opinions rest.
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Affiliation(s)
- C S Miller
- Department of Oral Health Science, University of Kentucky Colleges of Dentistry and Medicine, Lexington 40536-0084, USA
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14
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Smith CC, Peng T, Kulka M, Aurelian L. The PK domain of the large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) is required for immediate-early gene expression and virus growth. J Virol 1998; 72:9131-41. [PMID: 9765459 PMCID: PMC110331 DOI: 10.1128/jvi.72.11.9131-9141.1998] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The large subunit of herpes simplex virus (HSV) ribonucleotide reductase (RR), RR1, contains a unique amino-terminal domain which has serine/threonine protein kinase (PK) activity. To examine the role of the PK activity in virus replication, we studied an HSV type 2 (HSV-2) mutant with a deletion in the RR1 PK domain (ICP10DeltaPK). ICP10DeltaPK expressed a 95-kDa RR1 protein (p95) which was PK negative but retained the ability to complex with the small RR subunit, RR2. Its RR activity was similar to that of HSV-2. In dividing cells, onset of virus growth was delayed, with replication initiating at 10 to 15 h postinfection, depending on the multiplicity of infection. In addition to the delayed growth onset, virus replication was significantly impaired (1,000-fold lower titers) in nondividing cells, and plaque-forming ability was severely compromised. The RR1 protein expressed by a revertant virus [HSV-2(R)] was structurally and functionally similar to the wild-type protein, and the virus had wild-type growth and plaque-forming properties. The growth of the ICP10DeltaPK virus and its plaque-forming potential were restored to wild-type levels in cells that constitutively express ICP10. Immediate-early (IE) genes for ICP4, ICP27, and ICP22 were not expressed in Vero cells infected with ICP10DeltaPK early in infection or in the presence of cycloheximide, and the levels of ICP0 and p95 were significantly (three- to sevenfold) lower than those in HSV-2- or HSV-2(R)-infected cells. IE gene expression was similar to that of the wild-type virus in cells that constitutively express ICP10. The data indicate that ICP10 PK is required for early expression of the viral regulatory IE genes and, consequently, for timely initiation of the protein cascade and HSV-2 growth in cultured cells.
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Affiliation(s)
- C C Smith
- Virology/Immunology Laboratories, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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15
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Sawtell NM. The probability of in vivo reactivation of herpes simplex virus type 1 increases with the number of latently infected neurons in the ganglia. J Virol 1998; 72:6888-92. [PMID: 9658140 PMCID: PMC109900 DOI: 10.1128/jvi.72.8.6888-6892.1998] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The purpose of this study was to define the relationship between herpes simplex virus (HSV) latency and in vivo ganglionic reactivation. Groups of mice with numbers of latently infected neurons ranging from 1.9 to 24% were generated by varying the input titer of wild-type HSV type 1 strain 17syn+. Reactivation of the virus in mice from each group was induced by hyperthermic stress. The number of animals that exhibited virus reactivation was positively correlated with the number of latently infected neurons in the ganglia over the entire range examined (r = 0.9852, P < 0. 0001 [Pearson correlation]).
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Affiliation(s)
- N M Sawtell
- Division of Infectious Diseases, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA.
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16
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Tal-Singer R, Podrzucki W, Lasner TM, Skokotas A, Leary JJ, Fraser NW, Berger SL. Use of differential display reverse transcription-PCR to reveal cellular changes during stimuli that result in herpes simplex virus type 1 reactivation from latency: upregulation of immediate-early cellular response genes TIS7, interferon, and interferon regulatory factor-1. J Virol 1998; 72:1252-61. [PMID: 9445025 PMCID: PMC124603 DOI: 10.1128/jvi.72.2.1252-1261.1998] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/1997] [Accepted: 10/15/1997] [Indexed: 02/05/2023] Open
Abstract
The detailed mechanism which governs the choice between herpes simplex virus (HSV) latency and reactivation remains to be elucidated. It is probable that altered expression of cellular factors in sensory neurons leads to induction of HSV gene expression resulting in reactivation. As an approach to identify novel cellular genes which are activated or repressed by stimuli that reactivate HSV from latency and hence may play a role in viral reactivation, RNA from explanted trigeminal ganglia (TG) was analyzed by differential display reverse transcription-PCR (DDRT-PCR). Nearly 50 cDNAs whose mRNA level was modified by the stress of explantation were isolated and sequenced. We present a listing of a spectrum of altered RNAs, including both known and unknown sequences. Five of those differentially displayed transcripts were identified as interferon-related murine TIS7 mRNA. These results were confirmed in both infected and uninfected ganglia by quantitative RNase protection assay and immunostaining. Alpha and beta interferons and interferon regulatory factor-1 (IRF-1) were also induced by explantation. In addition, we have identified sequences that correspond to IRF-1 consensus binding sites in both HSV type 1 origins of replication. Our findings suggest that physiological pathways that include these cellular factors may be involved in modulating HSV reactivation.
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Affiliation(s)
- R Tal-Singer
- The Wistar Institute, Philadelphia, Pennsylvania 19104-4268, USA
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17
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Abstract
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.
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Affiliation(s)
- E K Wagner
- Department of Molecular Biology and Biochemistry, University of California, Irvine 92697-3900, USA.
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18
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Kimura S. Effects of nerve growth factor and phorbol derivative on reactivation of herpes simplex virus type 1 in cultured cells of latently infected adult mouse trigeminal ganglia. Microbiol Immunol 1996; 40:645-50. [PMID: 8908609 DOI: 10.1111/j.1348-0421.1996.tb01122.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Reactivation of herpes simplex virus type 1 (HSV-1) occurred rapidly in cells of latently infected adult mouse trigeminal ganglia which were cultured in serum-free medium in the presence of sufficient nerve growth factor (NGF). However, HSV-1 reactivation was delayed significantly in ganglionic cultures in the absence of exogenous NGF or in cultures treated with 2-aminopurine in the presence of NGF. The delayed viral reactivation in ganglionic cultures without NGF was accelerated by treatment with phorbol myristate acetate or dibutyryl cyclic AMP. Culture conditions which affected HSV-1 reactivation did not affect replication of HSV-1 in normal ganglionic cultures.
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Affiliation(s)
- S Kimura
- Department of Microbiology, Kochi Medical School, Japan
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19
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Kimura S. Reactivation of herpes simplex virus type 1 in cells of latently infected mouse trigeminal ganglia cultured in serum-free medium. Microbiol Immunol 1996; 40:243-6. [PMID: 8934680 DOI: 10.1111/j.1348-0421.1996.tb03332.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Herpes simplex virus type 1 (HSV-1) was reactivated more rapidly in cells of latently infected mouse trigeminal ganglia which were cultured in serum-free medium (after 3.7 days of cultivation) than in those cultured in serum-containing Dulbecco's modified Eagle's medium (after 8.5 days of cultivation). The concentration of calcium ion (Ca2+) in the medium affected HSV-1 reactivation in ganglionic cultures, and 0.9 mM was the optimum concentration for the reactivation. Reactivation was delayed significantly in ganglia put into culture 4 months or more after infection compared with those cultured 1 month after infection.
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Affiliation(s)
- S Kimura
- Department of Microbiology, Kochi Medical School, Japan
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20
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Abstract
Herpes simplex virus type 1 (HSV-1) reactivates from the nervous system and causes recurrent disease in end organs such as the eye and the lips. We found that the beta-adrenergic receptor blocker, propranolol, reduces HSV-1 reactivation in an animal model. Mice latent for McKrae strain HSV-1 were injected with propranolol or saline once a day for 3 successive days, and subjected to a brief period of hyperthermia on the second day to induce reactivation. Twenty-four hours after the third injection, swabs of the ocular surface and homogenates of the corneas and trigeminal ganglia were analyzed for the presence of infectious virus and viral DNA. Treatment with propranolol significantly decreased the appearance of infectious virus in the tear film, cornea, and trigeminal ganglia (P < 0.05, chi 2-test). The results suggest a possible new pharmacologic approach to suppressing herpesvirus reactivation in the nervous system and thereby preventing recurrent disease.
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Affiliation(s)
- B M Gebhardt
- LSU Eye Center, Louisiana State University Medical Center, School of Medicine, New Orleans 70112, USA
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21
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Saalfrank RW, Burak R, Reihs S, Löw N, Hampel F, Stachel HD, Lentmaier J, Peters K, Peters EM, von Schnering HG. Synthese und Struktur vier- und achtkerniger Chelatkomplexe – exohedraler Gastaustausch an Tetrahemispheraplexen. Angew Chem Int Ed Engl 1995. [DOI: 10.1002/ange.19951070911] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Kramer MF, Coen DM. Quantification of transcripts from the ICP4 and thymidine kinase genes in mouse ganglia latently infected with herpes simplex virus. J Virol 1995; 69:1389-99. [PMID: 7853471 PMCID: PMC188725 DOI: 10.1128/jvi.69.3.1389-1399.1995] [Citation(s) in RCA: 177] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Herpes simplex virus establishes latency in nervous tissue in which it is maintained for the life of the mammalian host, with occasional reactivation leading to subsequent spread. Latency-associated transcripts are abundant during latency, but viral proteins and productive cycle RNAs have not been detected. Using sensitive, quantitative PCR assays, we have quantified certain viral RNAs specific to productive-cycle genes in mouse ganglia latently infected with herpes simplex virus type 1. Sense-strand RNA specific to the essential immediate-early gene, ICP4, was present in most ganglia in variable amounts relative to the amount of viral DNA, with one to seven molecules of RNA per viral genome in about 20% of ganglia. In contrast, the amount of latency-associated transcripts was much less variable, at an average of 4 x 10(4) molecules per viral genome. The amounts of ICP4-specific RNA were similar at 30 and 60 days postinfection, and at least some of these transcripts initiated within a region consistent with utilization of the ICP4 promoter. RNA specific to the thymidine kinase gene, whose transcription in productive infection is dependent on ICP4, was present in latently infected ganglia at a maximum level of 3.2 x 10(6) molecules per ganglion (500 molecules per viral genome). ICP4-specific and tk-specific RNAs measured from the same samples showed a positive correlation extending over 2 orders of magnitude. We conclude that ICP4-specific RNA is expressed in the absence of detectable reactivation and discuss possible implications of our findings for latent gene expression.
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Affiliation(s)
- M F Kramer
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
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23
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Halford WP, Carr DJ. Subversion of intracellular signal transduction by herpes simplex virus type 1. ADVANCES IN NEUROIMMUNOLOGY 1995; 5:327-34. [PMID: 8748076 DOI: 10.1016/0960-5428(95)00017-v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- W P Halford
- Department of Microbiology, LSU Medical Center, New Orleans 70112-1393, USA
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24
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Hanson N, Henderson G, Jones C. The herpes simplex virus type 2 gene which encodes the large subunit of ribonucleotide reductase has unusual regulatory properties. Virus Res 1994; 34:265-80. [PMID: 7856314 DOI: 10.1016/0168-1702(94)90127-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Expression of herpes simplex virus type 2 (HSV-2) encoded ribonucleotide reductase (RR) is required for growth of the virus in non-dividing cells. The functional enzyme is composed of a large (RRA) and small (RRB) subunit and the enzyme is expressed as a delayed early activity. The promoter of RRA contains a cis-acting motif (TAATGARAT) which resembles those found in immediate early (IE) genes suggesting RRA is an IE gene. When primate cells were infected with HSV-2, low levels of RRA transcripts were expressed in the presence of cycloheximide indicating RRA is not a true IE gene. Conditions which allow for efficient RRA RNA expression in the presence of cycloheximide were identified in human cells. A phorbol ester, 12-O-tetradecanoyl phorbol-13- acetate (TPA), and hydroxyurea increased the level of RRA RNA expression in the presence of cycloheximide. Hydroxyurea and TPA also stimulated RRA promoter activity in transient assays suggesting these agents induced factors which transactivated the RRA promoter. Expression of an intact c-myc gene transactivated the RRA promoter more than 30-fold in transient assays. Although expression of an intact retinoblastoma gene (Rb) had a slight stimulatory effect on the RRA promoter, mutant Rb proteins also stimulated the RRA promoter. These studies demonstrated that inducible factors in permissive cells increase the steady state levels of RRA RNA in the presence of cycloheximide.
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MESH Headings
- Animals
- Base Sequence
- Cells, Cultured
- Cycloheximide/pharmacology
- DNA, Viral
- Gene Expression Regulation, Viral/drug effects
- Genes, Immediate-Early
- Genes, Retinoblastoma
- Genes, Viral
- Genes, myc
- Haplorhini
- Herpesvirus 2, Human/enzymology
- Herpesvirus 2, Human/genetics
- Humans
- Hydroxyurea/pharmacology
- Molecular Sequence Data
- Promoter Regions, Genetic
- RNA, Viral
- Ribonucleotide Reductases/genetics
- Tetradecanoylphorbol Acetate/pharmacology
- Transcription Factors/metabolism
- Transcriptional Activation
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Affiliation(s)
- N Hanson
- Department of Veterinary and Biomedical Sciences, University of Nebraska, Lincoln 68583-0905
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25
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Panet A, Braun E, Honigman A, Steiner I. Genetic pituitary dwarfism with high serum concentation of growth hormone--a new inborn error of metabolism? J Theor Biol 1966; 236:88-94. [PMID: 15967186 DOI: 10.1016/j.jtbi.2005.02.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2004] [Revised: 02/17/2005] [Accepted: 02/23/2005] [Indexed: 12/15/2022]
Abstract
Herpes simplex virus (HSV) 1 has adapted to the human host through two modes of infection, the acute-transient infection that may cause diseases (such as encephalitis) and the latent state, which is a source for recurrent infection and disease. While much information has been gathered on the cellular and molecular concomitants of establishment and maintenance of HSV-1 latent state, the biological basis of viral reactivation is still unclear. Despite their obvious differences, HSV-1 and the bacterial temperate virus, the bacteriophage lambda, shares four distinct features that may help understand the viral latency phenomenon: (i) two modes of life cycle and a decision point to choose either latency (HSV-1) and lysogeny (bacteriophage lambda), or active replication, that results in cell destruction, (ii) establishment of lysogeny/latency of the respective virus is associated with protection from cell death, (iii) immunity/resistance to super-infection, (iv) agents that trigger mammalian and bacterial cell death also induce reactivation of both HSV-1 and lambda bacteriophage. Thus, despite their differences, these two viruses might display analogous mechanism(s) of reactivation. Based on clinical and experimental data, we propose in this hypothesis that while HSV-1 latency, like bacteriophage lambda lysogeny, is associated with protection from cell death and restriction to super-infection, viral reactivation from the latent state is triggered by exogenous stress signals that interfere with cellular viability and may eventually lead to cell death.
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Affiliation(s)
- Amos Panet
- Department of Virology, Hadassah University Hospital, P.O. Box 12000, Jerusalem 91120, Israel
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