scholarly journals Functional Comparison of Herpes Simplex Virus 1 (HSV-1) and HSV-2 ICP27 Homologs Reveals a Role for ICP27 in Virion Release

2014 ◽  
Vol 89 (5) ◽  
pp. 2892-2905 ◽  
Author(s):  
Donglim Park ◽  
Joseph Lalli ◽  
Lenka Sedlackova-Slavikova ◽  
Stephen A. Rice
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Infected Cell ◽  
Regulatory Protein ◽  
Late Gene Expression ◽  
Herpes Simplex Virus 1 ◽  
Amino Terminal ◽  
Virion Release ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACTNumerous studies have focused on the regulatory functions of ICP27, an immediate-early (IE) protein of herpes simplex virus 1 (HSV-1). However, its homolog in HSV-2, termed ICP27t2, has been little studied. Here, we used two different approaches to functionally compare ICP27t2 and ICP27. In transfection-based assays, ICP27t2 closely resembled ICP27 in its capacity to enhance HSV-1 late gene expression, suppress the splicing of a viral intron, and complement the growth of an HSV-1 ICP27 null mutant. To study ICP27t2 in the context of viral infection, we engineered K2F1, an HSV-1 mutant that encodes ICP27t2 in place of ICP27. In Vero cells, K2F1 replicated with wild-type (WT) kinetics and yields, expressed delayed-early and late proteins normally, and was fully capable of activating several cellular signal transduction pathways that are ICP27 dependent. Thus, we conclude that ICP27t2 and ICP27 are functionally very similar and that ICP27t2 can mediate all ICP27 activities that are required for HSV-1 replication in cell culture. Surprisingly, however, we found that K2F1 forms plaques that are morphologically different from those of WT HSV-1. Investigation of this trait demonstrated that it results from the decreased release of progeny virions into the culture medium. This appears to be due to a reduction in the detachment of K2F1 progeny from the extracellular surface of the infected cell. We identified two HSV-1 ICP27 amino-terminal deletion mutants with a similar release defect. Together, these results demonstrate that ICP27 plays a heretofore-unappreciated role in modulating the efficiency of progeny virion release.IMPORTANCEICP27 is an essential, multifunctional regulatory protein that has a number of critical roles in the HSV-1 life cycle. Although ICP27 homologs are encoded by all known members of theHerpesviridae, previous work with several of these homologs has shown that they cannot substitute for ICP27 in the context of HSV-1-infected cells. Here, we identify ICP27t2 as the first homolog that can efficiently replace ICP27 in HSV-1 infection. Unexpectedly, our results also reveal that the sequence of the ICP27 gene can affect the release of HSV-1 progeny virions from the infected cell. Thus, our comparative study has revealed a novel function for ICP27 in the regulation of virus release.

scholarly journals Identification of Three Redundant Segments Responsible for Herpes Simplex Virus 1 ICP0 To Fuse with ND10 Nuclear Bodies

2015 ◽  
Vol 89 (8) ◽  
pp. 4214-4226 ◽  
Author(s):  
Yi Zheng ◽  
Haidong Gu
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Infected Cell ◽  
Nuclear Bodies ◽  
Cell Protein ◽  
Herpes Simplex Virus 1 ◽  
Infected Cell Protein ◽  
Simplex Virus ◽  
Hsv 1 ◽  
Infected Cell Protein 0

ABSTRACTInfected cell protein 0 (ICP0) of herpes simplex virus 1 (HSV-1) is a key regulator in both lytic and latent infections. In lytic infection, an important early event is the colocalization of ICP0 to nuclear domain 10 (ND10), the discrete nuclear bodies that impose restrictions on viral expression. ICP0 contains an E3 ubiquitin ligase that degrades promyelocytic leukemia protein (PML) and Sp100, two major components of ND10, and disperses ND10 to alleviate repression. We previously reported that the association between ICP0 and ND10 is a dynamic process that includes three steps: adhesion, fusion, and retention. ICP0 residues 245 to 474, defined as ND10 entry signal (ND10-ES), is a region required for the fusion step. Without ND10-ES, ICP0 adheres at the ND10 surface but fails to enter. In the present study, we focus on characterizing ND10-ES. Here we report the following. (i) Fusion of ICP0 with ND10 relies on specific sequences located within ND10-ES. Replacement of ND10-ES by the corresponding region from ORF61 of varicella-zoster virus did not rescue ND10 fusion. (ii) Three tandem ND10 fusion segments (ND10-FS1, ND10-FS2, and ND10-FS3), encompassing 200 amino acids within ND10-ES, redundantly facilitate fusion. Each of the three segments is sufficient to independently drive the fusion process, but none of the segments by themselves are necessary for ND10 fusion. Only when all three segments are deleted is fusion blocked. (iii) The SUMO interaction motif located within ND10-FS2 is not required for ND10 fusion but is required for the complete degradation of PML, suggesting that PML degradation and ND10 fusion are regulated by different molecular mechanisms.IMPORTANCEND10 nuclear bodies are part of the cell-intrinsic antiviral defenses that restrict viral gene expression upon virus infection. As a countermeasure, infected cell protein 0 (ICP0) of herpes simplex virus 1 (HSV-1) localizes to ND10s, degrades the ND10 organizer, and disperses ND10 components in order to alleviate repression. We studied the ICP0-ND10 association to delineate elements important for this dynamic interaction and to understand its role in viral replication and host defense. In this work, we show that ICP0 contains three redundant segments to ensure an effective mergence of ICP0 with ND10 nuclear bodies. This is the first study to systematically investigate ICP0 elements that are important for ICP0-ND10 fusion.

scholarly journals Characterization of the triplet repeats in the central domain of the γ 134·5 protein of herpes simplex virus 1

2005 ◽  
Vol 86 (9) ◽  
pp. 2411-2419 ◽  
Author(s):  
Xianghong Jing ◽  
Bin He
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Triplet Repeats ◽  
Herpes Simplex Virus 1 ◽  
Central Domain ◽  
Amino Terminal ◽  
Terminal Domain ◽  
Different Strains ◽  
Simplex Virus ◽  
Hsv 1

The γ 134·5 protein of herpes simplex virus 1 (HSV-1) consists of an amino-terminal domain, a central domain with triplet repeats (Ala–Thr–Pro) and a carboxyl-terminal domain. The triplet repeats are a unique feature of the γ 134·5 protein encoded by HSV-1, but the number of repeats varies among different strains. Notably, the central domain containing the triplet repeats is implicated in neuroinvasion. In this report, it has been shown that partial or full deletion of triplet repeats, i.e. from ten to either three or zero, in the γ 134·5 protein has no effect on the virus response to interferon. The triplet deletion mutants replicate efficiently in CV-1 and mouse 10T1/2 cells. However, in mouse 3T6 cells, these mutants grow with delayed growth kinetics. This decrease in growth, compared with wild-type HSV-1(F), does not result from failure of the virus to suppress the RNA-dependent protein kinase response, but rather from a delay in virus release or egress. Accordingly, these mutant viruses are predominantly present within infected cells. These results indicate that deletions in the central domain of the γ 134·5 protein impair virus egress, but not virus response to interferon.

Role of the arginine cluster in the disordered domain of Herpes Simplex Virus 1 UL34 for the recruitment of ESCRT-III for viral primary envelopment

2021 ◽  
Author(s):  
Jun Arii ◽  
Kosuke Takeshima ◽  
Yuhei Maruzuru ◽  
Naoto Koyanagi ◽  
Yoshitaka Nakayama ◽  
...  
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Nuclear Export ◽  
Herpes Simplex Virus 1 ◽  
Amino Terminal ◽  
Arginine Residues ◽  
Infected Cells ◽  
Simplex Virus ◽  
Hsv 1

During the nuclear export of nascent nucleocapsids of herpesviruses, the nucleocapsids bud through the inner nuclear membrane (INM) by acquiring the INM as a primary envelope (primary envelopment). We recently reported that herpes simplex virus 1 (HSV-1) nuclear egress complex (NEC), which consists of UL34 and UL31, interacts with an ESCRT-III adaptor ALIX and recruits ESCRT-III machinery to the INM for efficient primary envelopment. In this study, we identified a cluster of six arginine residues in the disordered domain of UL34 as a minimal region required for the interaction with ALIX as well as the recruitment of ALIX and an ESCRT-III protein CHMP4B to the INM in HSV-1-infected cells. Mutations in the arginine cluster exhibited phenotypes similar to those with ESCRT-III inhibition reported previously, including the mis-localization of NEC, induction of membranous invagination structures containing enveloped virions, aberrant accumulation of enveloped virions in the invaginations and perinuclear space, and reduction of viral replication. We also showed that the effect of the arginine cluster in UL34 on HSV-1 replication was dependent primarily on ALIX. These results indicated that the arginine cluster in the disordered domain of UL34 was required for the interaction with ALIX and the recruitment of ESCRT-III machinery to the INM to promote primary envelopment. IMPORTANCE Herpesvirus UL34 homologs contain conserved amino-terminal domains that mediate vesicle formation through interactions with UL31 homologs during primary envelopment. UL34 homologs also comprise other domains adjacent to their membrane-anchoring regions, which differ in length, are variable in herpesviruses and do not form distinguished secondary structures. However, the role of these disordered domains in infected cells remains to be elucidated. In this study, we present data suggesting that the arginine cluster in the disordered domain of HSV-1 UL34 mediates the interaction with ALIX, thereby leading to the recruitment of ESCRT-III machinery to the INM for efficient primary envelopment. This is the first study to report the role of the disordered domain of a UL34 homolog in herpesvirus infections.

scholarly journals Efficient Nuclear Export of Herpes Simplex Virus 1 Transcripts Requires both RNA Binding by ICP27 and ICP27 Interaction with TAP/NXF1

2008 ◽  
Vol 83 (3) ◽  
pp. 1184-1192 ◽  
Author(s):  
Lisa A. Johnson ◽  
Rozanne M. Sandri-Goldin
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Nuclear Export ◽  
Rna Binding ◽  
Regulatory Protein ◽  
Herpes Simplex Virus 1 ◽  
Cytoplasmic Rna ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT Herpes simplex virus 1 (HSV-1) regulatory protein ICP27 has been reported to bind viral RNA and to interact with the nuclear export adaptor Aly/REF and the major cellular mRNA nuclear export receptor TAP/NXF1. Using in situ hybridization and in vitro export assays, we show here that poly(A)+ RNA was retained in the nucleus of cells infected with viral ICP27 mutants that either cannot bind RNA or that do not interact with TAP/NXF1. Microarray analysis of nuclear and cytoplasmic RNA fractions demonstrated that efficient export of the majority of viral transcripts requires that ICP27 be able to bind RNA and to interact with TAP/NXF1. We conclude that ICP27 is the major export adaptor for HSV-1 mRNA and that it links bound transcripts to the TAP/NXF1 export receptor.

scholarly journals Herpes Simplex Virus 1 γ134.5 Protein Inhibits STING Activation That Restricts Viral Replication

2018 ◽  
Vol 92 (20) ◽  
Author(s):  
Shuang Pan ◽  
Xing Liu ◽  
Yijie Ma ◽  
Youjia Cao ◽  
Bin He
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Virulence Factor ◽  
Dna Sensing ◽  
Viral Inhibition ◽  
Herpes Simplex Virus 1 ◽  
Amino Terminal ◽  
Viral Virulence ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACTThe γ134.5 gene of herpes simplex virus 1 (HSV-1) encodes a virulence factor that promotes viral pathogenesis. Although it perturbs TANK-binding kinase 1 (TBK1) in the complex network of innate immune pathways, the underlying mechanism is obscure. Here we report that HSV-1 γ134.5 targets stimulator of interferon genes (STING) in the intracellular DNA recognition pathway that regulates TBK1 activation. In virus-infected cells the γ134.5 protein associates with and inactivates STING, which leads to downregulation of interferon regulatory factor 3 (IRF3) and IFN responses. Importantly, HSV-1 γ134.5 disrupts translocation of STING from the endoplasmic reticulum to Golgi apparatus, a process necessary to prime cellular immunity. Deletion of γ134.5 or its amino-terminal domain from HSV-1 abolishes the observed inhibitory activities. Consistently, an HSV mutant that lacks functional γ134.5 replicated less efficiently in STING+/+than in STING−/−mouse embryonic fibroblasts. Moreover, reconstituted expression of human STING in the STING−/−cells activated IRF3 and reduced viral growth. These results suggest that control of the DNA sensing pathway by γ134.5 is advantageous to HSV infection.IMPORTANCEViral inhibition of innate immunity contributes to herpes simplex virus pathogenesis. Although this complex process involves multiple factors, the underlying events remain unclear. We demonstrate that an HSV virulence factor γ134.5 precludes the activation of STING, a central adaptor in the intracellular DNA sensing pathway. Upon HSV infection, this viral protein engages with and inactivates STING. Consequently, it compromises host immunity and facilitates HSV replication. These observations uncover an HSV mechanism that is likely to mediate viral virulence.

scholarly journals ICP27 Phosphorylation Site Mutants Are Defective in Herpes Simplex Virus 1 Replication and Gene Expression

2009 ◽  
Vol 84 (5) ◽  
pp. 2200-2211 ◽  
Author(s):  
Santos Rojas ◽  
Kara A. Corbin-Lickfett ◽  
Laurimar Escudero-Paunetto ◽  
Rozanne M. Sandri-Goldin
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Regulatory Protein ◽  
Phosphorylation Site ◽  
Viral Gene ◽  
Small Ring ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT Herpes simplex virus 1 (HSV-1) protein ICP27 is a multifunctional regulatory protein that is posttranslationally modified by phosphorylation during viral infection. ICP27 has been shown to be phosphorylated on three serine residues, specifically serine residues 16 and 18, which are within casein kinase 2 (CK2) sites, and serine residue 114, which is within a protein kinase A (PKA) site. Phosphorylation is an important regulatory mechanism that is reversible and controls many signaling pathways, protein-protein interactions, and protein subcellular localization. To determine the role of phosphorylation in modulating the activities of ICP27, we constructed phosphorylation site mutations at each of the three serine residues. Single, double, and triple viral mutants were created in which alanine or glutamic acid was substituted for serines 16, 18, and 114. ICP27 phosphorylation site mutants were defective in viral replication and viral gene expression. Notably, ICP4-containing replication compartment formation was severely compromised, with the appearance of small ring-like structures that persisted even at late times after infection. Neither the colocalization of ICP27 with RNA polymerase II nor the formation of Hsc70 nuclear foci was observed during infection with the phosphorylation site mutants, both of which occur during wild-type HSV-1 infection. These data indicate that several key events in which ICP27 plays a role are curtailed during infection with ICP27 phosphorylation site mutants.

scholarly journals Arginine Methylation of the ICP27 RGG Box Regulates ICP27 Export and Is Required for Efficient Herpes Simplex Virus 1 Replication

2009 ◽  
Vol 83 (11) ◽  
pp. 5309-5320 ◽  
Author(s):  
Stuart K. Souki ◽  
Paul D. Gershon ◽  
Rozanne M. Sandri-Goldin
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Regulatory Protein ◽  
Arginine Methylation ◽  
Spectrometric Analysis ◽  
Wild Type ◽  
Herpes Simplex Virus 1 ◽  
Arginine Residues ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT The herpes simplex virus 1 (HSV-1) multifunctional regulatory protein ICP27 shuttles between the nucleus and cytoplasm in its role as a viral mRNA export factor. Arginine methylation on glycine- and arginine-rich motifs has been shown to regulate protein export. ICP27 contains an RGG box and has been shown to be methylated during viral infection. We found by mass spectrometric analysis that three arginine residues within the RGG box were methylated. Viral mutants with substitutions of lysine for arginine residues were created as single, double, and triple mutants. Growth of these mutants was impaired and the viral replication cycle was delayed compared to wild-type HSV-1. Most striking was the finding that under conditions of hypomethylation resulting from infection with arginine substitution mutants or treatment of wild-type HSV-1-infected cells with the methylation inhibitor adenosine dialdehyde, ICP27 export to the cytoplasm occurred earlier and was more rapid than wild-type ICP27 export. We conclude that arginine methylation of the ICP27 RGG box regulates its export activity and that early export of ICP27 interferes with the performance of its nuclear functions.

Assembly of VP26 in herpes simplex virus-1 capsid implicated by 3-D structure of recombinant capsid

1995 ◽  
Vol 53 ◽  
pp. 840-841
Author(s):  
Z. Hong Zhou ◽  
Jing He ◽  
Joanita Jakana ◽  
J. D. Tatman ◽  
Frazer J. Rixon ◽  
...  
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
3D Structure ◽  
Structure Study ◽  
Herpes Simplex Virus 1 ◽  
Shell Proteins ◽  
Life Threatening ◽  
Infected Cells ◽  
Simplex Virus ◽  
Hsv 1

Herpes simplex virus-1 (HSV-1) is a ubiquitous virus which is implicated in diseases ranging from self-curing cold sores to life-threatening infections. The 2500 Å diameter herpes virion is composed of a glycoprotein spike containing, lipid envelope, enclosing a protein layer (the tegument) in which is embedded the capsid (which contains the dsDNA genome). The B-, and A- and C-capsids, representing different morphogenetic stages in HSV-1 infected cells, are composed of 7, and 5 structural proteins respectively. The three capsid types are organized in similar T=16 icosahedral shells with 12 pentons, 150 hexons, and 320 connecting triplexes. Our previous 3D structure study at 26 Å revealed domain features of all these structural components and suggested probable locations for the outer shell proteins, VP5, VP26, VP19c and VP23. VP5 makes up most of both pentons and hexons. VP26 appeared to bind to the VP5 subunit in hexon but not to that in penton.

scholarly journals Herpes simplex virus 1 targets IRF7 via ICP0 to limit type I IFN induction

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
David Shahnazaryan ◽  
Rana Khalil ◽  
Claire Wynne ◽  
Caroline A. Jefferies ◽  
Joan Ní Gabhann-Dromgoole ◽  
...  
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Immune Responses ◽  
Tear Film ◽  
Cell Protein ◽  
Type I ◽  
Type I Ifn ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1

AbstractHerpes simplex keratitis (HSK), caused by herpes simplex virus type 1 (HSV-1) infection, is the commonest cause of infectious blindness in the developed world. Following infection the virus is initially suspended in the tear film, where it encounters a multi-pronged immune response comprising enzymes, complement, immunoglobulins and crucially, a range of anti-viral and pro-inflammatory cytokines. However, given that HSV-1 can overcome innate immune responses to establish lifelong latency throughout a susceptible individual’s lifetime, there is significant interest in understanding the mechanisms employed by HSV-1 to downregulate the anti-viral type I interferon (IFN) mediated immune responses. This study aimed to investigate the interactions between infected cell protein (ICP)0 and key elements of the IFN pathway to identify possible novel targets that contribute to viral immune evasion. Reporter gene assays demonstrated the ability of ICP0 to inhibit type I IFN activity downstream of pathogen recognition receptors (PRRs) which are known to be involved in host antiviral defences. Further experiments identified interferon regulatory factor (IRF)7, a driver of type I IFN, as a potential target for ICP0. These findings increase our understanding of the pathogenesis of HSK and suggest IRF7 as a potential therapeutic target.

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

Viruses ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document