Function of the Herpes Simplex Virus 1 Small Capsid Protein VP26 Is Regulated by Phosphorylation at a Specific Site

Replacement of the herpes simplex virus 1 small capsid protein VP26 phosphorylation site Thr-111 with alanine reduced viral replication and neurovirulence to levels observed with the VP26 null mutation. This mutation reduced VP26 expression and mislocalized VP26 and its binding partner, the major capsid protein VP5, in the nucleus. VP5 mislocalization was also observed with the VP26 null mutation. Thus, we postulate that phosphorylation of VP26 at Thr-111 regulates VP26 functionin vitroandin vivo.

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Structural Variability of the Herpes Simplex Virus 1 GenomeIn VitroandIn Vivo

Journal of Virology ◽

10.1128/jvi.00223-12 ◽

2012 ◽

Vol 86 (16) ◽

pp. 8592-8601 ◽

Cited By ~ 9

Author(s):

Charlotte Mahiet ◽

Ayla Ergani ◽

Nicolas Huot ◽

Nicolas Alende ◽

Ahmed Azough ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Considerable Proportion ◽

Inverted Repeats ◽

Herpes Simplex Virus 1 ◽

Cell Extracts ◽

Simplex Virus ◽

Hsv 1

Herpes simplex virus 1 (HSV-1) is a human pathogen that leads to recurrent facial-oral lesions. Its 152-kb genome is organized in two covalently linked segments, each composed of a unique sequence flanked by inverted repeats. Replication of the HSV-1 genome produces concatemeric molecules in which homologous recombination events occur between the inverted repeats. This mechanism leads to four genome isomers (termed P, IS, IL, and ILS) that differ in the relative orientations of their unique fragments. Molecular combing analysis was performed on DNA extracted from viral particles and BSR, Vero, COS-7, and Neuro-2a cells infected with either strain SC16 or KOS of HSV-1, as well as from tissues of experimentally infected mice. Using fluorescence hybridization, isomers were repeatedly detected and distinguished and were accompanied by a large proportion of noncanonical forms (40%). In both cell and viral-particle extracts, the distributions of the four isomers were statistically equivalent, except for strain KOS grown in Vero and Neuro-2a cells, in which P and IS isomers were significantly overrepresented. In infected cell extracts, concatemeric molecules as long as 10 genome equivalents were detected, among which, strikingly, the isomer distributions were equivalent, suggesting that any such imbalance may occur during encapsidation.In vivo, for strain KOS-infected trigeminal ganglia, an unbalanced distribution distinct from the onein vitrowas observed, along with a considerable proportion of noncanonical assortment.

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Restoring Herpesvirus Entry Mediator (HVEM) Immune Function in HVEM−/− Mice Rescues Herpes Simplex Virus 1 Latency and Reactivation Independently of Binding to Glycoprotein D

Journal of Virology ◽

10.1128/jvi.00700-20 ◽

2020 ◽

Vol 94 (16) ◽

Author(s):

Kati Tormanen ◽

Shaohui Wang ◽

Ujjaldeep Jaggi ◽

Homayon Ghiasi

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Immune Function ◽

Interleukin 2 ◽

Glycoprotein D ◽

Herpes Simplex Virus 1 ◽

Simplex Virus ◽

Hsv 1

ABSTRACT The immune modulatory protein herpes virus entry mediator (HVEM) is one of several cellular receptors used by herpes simplex virus 1 (HSV-1) for cell entry. HVEM binds to HSV-1 glycoprotein D (gD) but is not necessary for HSV-1 replication in vitro or in vivo. Previously, we showed that although HSV-1 replication was similar in wild-type (WT) control and HVEM−/− mice, HSV-1 does not establish latency or reactivate effectively in mice lacking HVEM, suggesting that HVEM is important for these functions. It is not known whether HVEM immunomodulatory functions contribute to latency and reactivation or whether its binding to gD is necessary. We used HVEM−/− mice to establish three transgenic mouse lines that express either human WT HVEM or human or mouse HVEM with a point mutation that ablates its ability to bind to gD. Here, we show that HVEM immune function, not its ability to bind gD, is required for WT levels of latency and reactivation. We further show that HVEM binding to gD does not affect expression of the HVEM ligands BTLA, CD160, or LIGHT. Interestingly, our results suggest that binding of HVEM to gD may contribute to efficient upregulation of CD8α but not PD1, TIM-3, CTLA4, or interleukin 2 (IL-2). Together, our results establish that HVEM immune function, not binding to gD, mediates establishment of latency and reactivation. IMPORTANCE HSV-1 is a common cause of ocular infections worldwide and a significant cause of preventable blindness. Corneal scarring and blindness are consequences of the immune response induced by repeated reactivation events. Therefore, HSV-1 therapeutic approaches should focus on preventing latency and reactivation. Our data suggest that the immune function of HVEM plays an important role in the HSV-1 latency and reactivation cycle that is independent of HVEM binding to gD.

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A novel bioluminescent herpes simplex virus 1 for in vivo monitoring of herpes simplex encephalitis

Scientific Reports ◽

10.1038/s41598-021-98047-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Olus Uyar ◽

Pier-Luc Plante ◽

Jocelyne Piret ◽

Marie-Christine Venable ◽

Julie Carbonneau ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Cell Culture Supernatant ◽

Herpes Simplex Virus Encephalitis ◽

Herpes Simplex Virus 1 ◽

Simplex Virus ◽

Hsv 1 ◽

Viral Titers

AbstractHerpes simplex virus 1 (HSV-1) is responsible for herpes simplex virus encephalitis (HSE), associated with a 70% mortality rate in the absence of treatment. Despite intravenous treatment with acyclovir, mortality remains significant, highlighting the need for new anti-herpetic agents. Herein, we describe a novel neurovirulent recombinant HSV-1 (rHSV-1), expressing the fluorescent tdTomato and Gaussia luciferase (Gluc) enzyme, generated by the Clustered regularly interspaced short palindromic repeats (CRISPR)—CRISPR-associated protein 9 (Cas9) (CRISPR-Cas9) system. The Gluc activity measured in the cell culture supernatant was correlated (P = 0.0001) with infectious particles, allowing in vitro monitoring of viral replication kinetics. A significant correlation was also found between brain viral titers and Gluc activity in plasma (R2 = 0.8510, P < 0.0001) collected from BALB/c mice infected intranasally with rHSV-1. Furthermore, evaluation of valacyclovir (VACV) treatment of HSE could also be performed by analyzing Gluc activity in mouse plasma samples. Finally, it was also possible to study rHSV-1 dissemination and additionally to estimate brain viral titers by in vivo imaging system (IVIS). The new rHSV-1 with reporter proteins is not only as a powerful tool for in vitro and in vivo antiviral screening, but can also be used for studying different aspects of HSE pathogenesis.

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Activated MEK Suppresses Activation of PKR and Enables Efficient Replication and In Vivo Oncolysis by Δγ134.5 Mutants of Herpes Simplex Virus 1

Journal of Virology ◽

10.1128/jvi.80.3.1110-1120.2006 ◽

2006 ◽

Vol 80 (3) ◽

pp. 1110-1120 ◽

Cited By ~ 72

Author(s):

Kerrington D. Smith ◽

James J. Mezhir ◽

Kai Bickenbach ◽

Jula Veerapong ◽

Jean Charron ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Tumor Cells ◽

Cell Lines ◽

Human Tumor ◽

Dominant Negative ◽

Herpes Simplex Virus 1 ◽

Simplex Virus

ABSTRACT Herpes simplex virus mutants lacking the γ134.5 gene are not destructive to normal tissues but are potent cytolytic agents in human tumor cells in which the activation of double-stranded RNA-dependent protein kinase (PKR) is suppressed. Thus, replication of a Δγ134.5 mutant (R3616) in 12 genetically defined cancer cell lines correlates with suppression of PKR but not with the genotype of RAS. Extensive analyses of two cell lines transduced with either dominant negative MEK (dnMEK) or constitutively active MEK (caMEK) indicated that in R3616 mutant-infected cells dnMEK enabled PKR activation and decreased virus yields, whereas caMEK suppressed PKR and enabled better viral replication and cell destruction in transduced cells in vitro or in mouse xenografts. The results indicate that activated MEK mediates the suppression of PKR and that the status of MEK predicts the ability of Δγ134.5 mutant viruses to replicate in and destroy tumor cells.

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Persistent Infection with Herpes Simplex Virus 1 and Alzheimer’s Disease—A Call to Study How Variability in Both Virus and Host may Impact Disease

Viruses ◽

10.3390/v11100966 ◽

2019 ◽

Vol 11 (10) ◽

pp. 966 ◽

Cited By ~ 5

Author(s):

Colleen A. Mangold ◽

Moriah L. Szpara

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Future Research ◽

Herpes Simplex Virus 1 ◽

Simplex Virus ◽

Hsv 1

Increasing attention has focused on the contributions of persistent microbial infections with the manifestation of disease later in life, including neurodegenerative conditions such as Alzheimer’s disease (AD). Current data has shown the presence of herpes simplex virus 1 (HSV-1) in regions of the brain that are impacted by AD in elderly individuals. Additionally, neuronal infection with HSV-1 triggers the accumulation of amyloid beta deposits and hyperphosphorylated tau, and results in oxidative stress and synaptic dysfunction. All of these factors are implicated in the development of AD. These data highlight the fact that persistent viral infection is likely a contributing factor, rather than a sole cause of disease. Details of the correlations between HSV-1 infection and AD development are still just beginning to emerge. Future research should investigate the relative impacts of virus strain- and host-specific factors on the induction of neurodegenerative processes over time, using models such as infected neurons in vitro, and animal models in vivo, to begin to understand their relationship with cognitive dysfunction.

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The US11 Gene of Herpes Simplex Virus 1 Promotes Neuroinvasion and Periocular Replication following Corneal Infection

Journal of Virology ◽

10.1128/jvi.02246-18 ◽

2019 ◽

Vol 93 (9) ◽

Author(s):

Audra J. Charron ◽

Stephen L. Ward ◽

Brian J. North ◽

Stacey Ceron ◽

David A. Leib

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Trigeminal Ganglia ◽

Herpes Simplex Virus 1 ◽

Corneal Infection ◽

Simplex Virus ◽

Phosphorylated Eif2α ◽

Hsv 1

ABSTRACTHerpes simplex virus 1 (HSV-1) cycles between phases of latency in sensory neurons and replication in mucosal sites. HSV-1 encodes two key proteins that antagonize the shutdown of host translation, US11 through preventing PKR activation and ICP34.5 through mediating dephosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α). While profound attenuation of ICP34.5 deletion mutants has been repeatedly demonstrated, a role for US11 in HSV-1 pathogenesis remains unclear. We therefore generated an HSV-1 strain 17 US11-null virus and examined its propertiesin vitroandin vivo. In U373 glioblastoma cells, US11 cooperated with ICP34.5 to prevent eIF2α phosphorylation late in infection. However, the effect was muted in human corneal epithelial cells (HCLEs), which did not accumulate phosphorylated eIF2α unless both US11 and ICP34.5 were absent. Low levels of phosphorylated eIF2α correlated with continued protein synthesis and with the ability of virus lacking US11 to overcome antiviral immunity in HCLE and U373 cells. Neurovirulence following intracerebral inoculation of mice was not affected by the deletion of US11. In contrast, the time to endpoint criteria following corneal infection was greater for the US11-null virus than for the wild-type virus. Replication in trigeminal ganglia and periocular tissue was promoted by US11, as was periocular disease. The establishment of latency and the frequency of virus reactivation from trigeminal ganglia were unaffected by US11 deletion, although emergence of the US11-null virus occurred with slowed kinetics. Considered together, the data indicate that US11 facilitates the countering of antiviral response of infected cells and promotes the efficient emergence of virus following reactivation.IMPORTANCEAlphaherpesviruses are ubiquitous DNA viruses and include the human pathogens herpes simplex virus 1 (HSV-1) and HSV-2 and are significant causes of ulcerative mucosal sores, infectious blindness, encephalitis, and devastating neonatal disease. Successful primary infection and persistent coexistence with host immune defenses are dependent on the ability of these viruses to counter the antiviral response. HSV-1 and HSV-2 and other primate viruses within theSimplexvirusgenus encode US11, an immune antagonist that promotes virus production by preventing shutdown of protein translation. Here we investigated the impact of US11 deletion on HSV-1 growthin vitroand pathogenesisin vivo. This work supports a role for US11 in pathogenesis and emergence from latency, elucidating immunomodulation by this medically important cohort of viruses.

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Identification of an Essential Domain in the Herpes Simplex Virus 1 UL34 Protein That Is Necessary and Sufficient To Interact with UL31 Protein

Journal of Virology ◽

10.1128/jvi.79.6.3797-3806.2005 ◽

2005 ◽

Vol 79 (6) ◽

pp. 3797-3806 ◽

Cited By ~ 42

Author(s):

Li Liang ◽

Joel D. Baines

Keyword(s):

Amino Acids ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Nuclear Membrane ◽

Fluorescent Protein ◽

Herpes Simplex Virus 1 ◽

Infected Cells ◽

Simplex Virus

ABSTRACT Previous results have indicated that the herpes simplex virus 1 UL31 and UL34 proteins interact and form a complex at the inner nuclear membranes of infected cells, where both play important roles in the envelopment of nucleocapsids at the inner nuclear membrane. In the work described here, mapping studies using glutathione S-transferase pull-down assays indicated that amino acids 137 to 181 of the UL34 protein are sufficient to mediate an interaction with the UL31 protein. A recombinant virus (v3480) lacking UL34 codons 138 to 181 was constructed. Similar to a UL34 null virus, v3480 failed to replicate on Vero cells and grew to a limited extent on rabbit skin cells. A UL34-expressing cell line restored v3480 growth and plaque formation. Similar to the localization of UL31 protein in cells infected with a UL34 null virus, the UL31 protein was present in the nuclei of Hep2 cells infected with v3480. Hep2 cells infected with v3480 contained the UL34 protein in the cytoplasm, the nucleus, and the nuclear membrane, and this was noted to be similar to the appearance of cells infected with a UL31 null virus. In transient expression assays, the interaction between UL34 amino acids 137 to 181 and the UL31 protein was sufficiently robust to target green fluorescent protein and emerin to intranuclear sites that contained the UL31 protein. These data indicate that amino acids 137 to 181 of the UL34 protein are (i) sufficient to mediate interactions with the UL31 protein in vitro and in vivo, (ii) necessary for the colocalization of UL31 and UL34 in infected cells, and (iii) essential for normal viral replication.

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Identification of a Physiological Phosphorylation Site of the Herpes Simplex Virus 1-Encoded Protein Kinase Us3 Which Regulates Its Optimal Catalytic Activity In Vitro and Influences Its Function in Infected Cells

Journal of Virology ◽

10.1128/jvi.00044-08 ◽

2008 ◽

Vol 82 (13) ◽

pp. 6172-6189 ◽

Cited By ~ 66

Author(s):

Akihisa Kato ◽

Michiko Tanaka ◽

Mayuko Yamamoto ◽

Risa Asai ◽

Tetsutaro Sata ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Protein Kinase ◽

Kinase Activity ◽

Phosphorylation Site ◽

Herpes Simplex Virus 1 ◽

Infected Cells ◽

Simplex Virus ◽

Hsv 1

ABSTRACT Us3 is a serine/threonine protein kinase encoded by herpes simplex virus 1 (HSV-1). Here, we report the identification of a physiological Us3 phosphorylation site on serine at position 147 (Ser-147) which regulates its protein kinase activity in vitro. Moreover, mutation of this site influences Us3 function, including correct localization of the enzyme and induction of the usual morphological changes in HSV-1-infected cells. These conclusions are based on the following observations: (i) in in vitro kinase assays, a domain of Us3 containing Ser-147 was specifically phosphorylated by Us3 and protein kinase A, while a mutant domain in which Ser-147 was replaced with alanine was not; (ii) in vitro, alanine replacement of Ser-147 (S147A) in Us3 resulted in significant impairment of the kinase activity of the purified molecule expressed in a baculovirus system; (iii) phosphorylation of Ser-147 in Us3 tagged with the monomeric fluorescent protein (FP) VenusA206K (VenusA206K-Us3) from Vero cells infected with a recombinant HSV-1 encoding VenusA206K-Us3 was specifically detected using an antibody that recognizes phosphorylated serine or threonine residues with arginine at the −3 and −2 positions; and (iv) the S147A mutation influenced some but not all Us3 functions, including the ability of the protein to localize itself properly and to induce wild-type cytopathic effects in infected cells. Our results suggest that some of the regulatory activities of Us3 in infected cells are controlled by phosphorylation at Ser-147.

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Antiviral Activity of the G-Quadruplex Ligand TMPyP4 against Herpes Simplex Virus-1

Viruses ◽

10.3390/v13020196 ◽

2021 ◽

Vol 13 (2) ◽

pp. 196

Author(s):

Sara Artusi ◽

Emanuela Ruggiero ◽

Matteo Nadai ◽

Beatrice Tosoni ◽

Rosalba Perrone ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Dna Replication ◽

Herpes Simplex ◽

Antiviral Activity ◽

Herpes Simplex Virus 1 ◽

Tem Analysis ◽

Infected Cells ◽

Simplex Virus ◽

Hsv 1

The herpes simplex virus 1 (HSV-1) genome is extremely rich in guanine tracts that fold into G-quadruplexes (G4s), nucleic acid secondary structures implicated in key biological functions. Viral G4s were visualized in HSV-1 infected cells, with massive virus cycle-dependent G4-formation peaking during viral DNA replication. Small molecules that specifically interact with G4s have been shown to inhibit HSV-1 DNA replication. We here investigated the antiviral activity of TMPyP4, a porphyrin known to interact with G4s. The analogue TMPyP2, with lower G4 affinity, was used as control. We showed by biophysical analysis that TMPyP4 interacts with HSV-1 G4s, and inhibits polymerase progression in vitro; in infected cells, it displayed good antiviral activity which, however, was independent of inhibition of virus DNA replication or entry. At low TMPyP4 concentration, the virus released by the cells was almost null, while inside the cell virus amounts were at control levels. TEM analysis showed that virus particles were trapped inside cytoplasmatic vesicles, which could not be ascribed to autophagy, as proven by RT-qPCR, western blot, and immunofluorescence analysis. Our data indicate a unique mechanism of action of TMPyP4 against HSV-1, and suggest the unprecedented involvement of currently unknown G4s in viral or antiviral cellular defense pathways.

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