ABSTRACT
In this study, emotional stress-induced herpes simplex virus type 1(HSV-1) susceptibility model was employed to simu-late the pathological state of " depression-induced liver fire", and the protection effect of Qingre Xiaoyanning(QX) in clearing liver fire was investigated. BALB/c mice were randomly divided into a normal group, a HSV-1 group, a restraint stress + HSV-1 group,low-(0. 658 g·kg~(-1)) and high-dose(1. 316 g·kg~(-1)) QX groups, and an acyclovir group. Except for the normal group and the HSV-1 group, the mice in other groups received daily restraint stress for 6 h from day 3 of medication. On day 9 of medication, mice were anesthetized by isoflurane and infected intranasally with HSV-1. Survival rate, weight change, encephalitis symptoms, and eye injury of mice were recorded for 14 d after virus infection. Hematoxylin-eosin(HE) staining and immunohistochemical staining were used to detect pathological changes and HSV-1 antigen distribution. Plaque assay was performed to detect the titer of HSV-1. The protein ex-pression of ICP27 in the mouse brain was detected by Western blot. The experimental results showed that QX could increase the survival rate of HSV-1-infected mice loaded with emotional stress(P<0. 001), reduce the titer of HSV-1 in the mouse brain(P<0. 01), relieve brain inflammation(P<0. 05) and eye injury(P<0. 05), down-regulate the expression of ICP27 related to HSV-1(P<0. 05), and decrease the distribution of HSV-1 antigen in the mouse brain. The results demonstrated that QX significantly reduced the susceptibility to HSV-1 induced by emotional stress, which is expected to provide a theoretical basis for the treatment and preven-tion of HSV-1 infection and promote the clinical development and application of Chinese medicine effective in clearing liver fire.
Subject(s)
Animals , Mice , Capsules , Herpes Simplex , Herpesvirus 1, Human , Mice, Inbred BALB C , Psychological DistressABSTRACT
The function of the herpes simplex virus type 1(HSV-1)UL4 protein is still elusive. Our objective is to investigate the subcellular transport mechanism of the UL4 protein. In this study,fluorescence microscopy was employed to investigate the subcellular localization of UL4 and characterize the transport mechanism in living cells. By constructing a series of deletion mutants fused with enhanced yellow fluorescent protein(EYFP),the nuclear export signals(NES)of UL4 were for the first time mapped to amino acid residues 178 to 186. In addition,the N-terminal 19 amino acids are identified to be required for the granule-like cytoplasmic pattern of UL4.Furthermore,the UL4 protein was demonstrated to be exported to the cytoplasm through the NES in a chromosomal region maintenance 1(CRM l)-dependent manner involving RanGTP hydrolysis.
ABSTRACT
Herpes simplex virus type 1 (HSV-1) is the causative agent of cold sores and other more serious diseases. HSV-1 infected-cell protein 27 (ICP27) is an immediate-early regulatory phosphoprotein homologous to gene products identified in all classes of herpesviruses so far. To raise the antiserum to ICP27 for further characterization of its biological function, the ICP27 gene was cloned into the pET-28a (+) vector, then ICP27 protein was expressed in E. Coli and purified by nickel-nitrilotriacetic acid (Ni2+-NTA) affinity resin column,finally the purified protein was used to raise antiserum. Western blot analysis demonstrated that the antiserum recognized the recombinant protein, and the antiserum was able to probe the ICP27 in HSV-1 infected cells with high specificity by immunofluorescence assay (IFA). Therefore, the specific antiserum will provide a valuable tool for further studies investigating ICP27's biological function during HSV-1 infection.
ABSTRACT
The protein HTRP (human transcription regulator protein) is encoded by the differential gene htrp and induced by Herpes simplex virus type 1 (HSV-1) infection in KMB-17 cells. HTRP was found to interact with SAP30 (mSin3A Association Protein), one of the components of co-repressor complex mSin3A, which is part of the deacetylation transfer enzyme HDAC. To reveal the biological significance of the interaction between HTRP and SAP30, real- time PCR and a dual-luciferase detecting system was used. The results indicate that HTRP could inhibit the transcription of a viral promoter, whose interaction with SAP30 synergistically affects transcriptional inhibition of the viral genes, and is related to HDAC enzyme activity. ChIP experiments demonstrate that HTRP could promote HDAC activity by increasing the deacetylation level of lysine 14 and lysine 9 in histone H3.
ABSTRACT
In this study,a standard strain of HSV-1(strain SM44)was used to investigate the antiviral activity of the recombinant Cyanovirin-N(CV-N)against Herpes simplex virus type 1(HSV-1)in vitro and in vivo.Cytopathic effect(CPE)and MTT assays were used to evaluate the effect of CV-N on HSV-1 in Vero cells.The number of copies of HSV-DNA was detected by real-time fluorescence quantitative PCR(FQ-PCR).The results showed that CV-N had a low cytotoxicity on Vero cells with a CC50 of 359.03±0.56 μg/mL,and that it could not directly inactivate HSV-1 infectivity.CV-N not only reduced the CPE of HSV-1 when added before or after viral infection,with a 50% inhibitory concentration(IC50)with 2.26 and 30.16μg/mL respectively,but it also decreased the copies of HSV-1 DNA in infected host cells.The encephalitis model for HSV-1 infection was conducted in Kunming mice,and treated with three dosages of CV-N(0.5,5 & 10 mg/kg)which was administered intraperitoneally at 2h,3d,5d,7d post infection.The duration for the appearance of symptoms of encephalitis and the survival days were recorded and brain tissue samples were obtained for pathological examination(HEstaining).Compared with the untreated control group,in the 5mg/kg CV-N and 10mg/kg CV-N treated groups,the mice suffered light symptoms and the number of survival days were more than 9d and 14d respectively.HE staining also showed that in 5mg/kg CV-N and 10mg/kg CV-N treated groups,the brain cells did not show visible changes,except for a slight inflammation.Our results demonstrated that CV-N has pronounced antiviral activity against HSV-1 both in vitro and in vivo,and it would be a promising new candidate for anti-HSV therapeutics.
ABSTRACT
The herpes simplex virus type 1 (HSV-1) VP22, is one of the most abundant HSV-1 tegument proteins with an average stoichiometry of 2 400 copies per virion and conserved among alphaherpesvirinae. Many functions are attributed to VP22, including nuclear localization, chromatin binding, microtubule binding, induction of microtubule reorganization, intercellular transport, interaction with cellular proteins, such as template activating factor I (TAF-I) and nonmuscle myosin II A (NMIIA), and viral proteins including tegument protein VP16, pUS9 and pUL46, glycoprotein E (gE) and gD. Recently, many novel functions performed by the HSV-1 VP22 protein have been shown, including promotion of protein synthesis at late times in infection, accumulation of a subset of viral mRNAs at early times in infection and possible transcriptional regulation function.
ABSTRACT
Herpes simplex virus type-1 (HSV-1) is one of many pathogens that use the cell surface glycosaminoglycan heparan sulfate as a receptor.Heparan sulfate is highly expressed on the surface and extracellular matrix of virtually all cell types making it an ideal receptor.Heparan sulfate interacts with HSV-1 envelope glycoproteins gB and gC during the initial attachment step during HSV-1 entry.In addition,a modified form of heparan sulfate,known as 3-O-sulfated heparan sulfate,interacts with HSV-1 gD to induce fusion between the viral envelope and host cell membrane.The 3-O-sulfation of heparan sulfate is a rare modification which occurs during the biosynthesis of heparan sulfate that is carded out by a family of enzymes known as 3-O-sulfotransferases.Due to its involvement in multiple steps of the infection process,heparan sulfate has been a prime target for the development of agents to inhibit HSV entry.Understanding how heparan sulfate functions during HSV-1 infection may not only be critical for inhibiting infection by this virus,but it may also be crucial in the fight against many other pathogens as well.
ABSTRACT
The three immediate-early proteins of HSV-1, ICPO, ICP22, and ICP27, have specific and pivotal functions in transcriptional activation and inhibition, multiple regulatory and control processes of viral genes. In this paper, the expression and localization of these three proteins were studied in neuroblastoma cells using biochemical assays, and their possible and potential interactive functions are discussed. The data show that the three proteins are localized in different structures, specifically in the PML-NB-associated structure, which is a specific nuclear structure composed of many protein molecules and bound tightly to the nuclear matrix in neuroblastoma cells. The results suggest that the activating and suppressive functions of ICPs are mostly dependent on their transcriptional and regulatory roles, including the PML-NB-associated structure.
ABSTRACT
The herpes simplex virus type 1 (HSV-1) infected-cell protein 27 (ICP27) is an essential,highly conserved protein involved in various steps of HSV-1 gene regulation as well as in the shut-off of host gene expression during infection.It functions primarily at the post-transcriptional level in inhibiting precursor mRNA splicing and in promoting nuclear export of viral transcripts.Recently,many novel functions performed by the HSV-1 ICP27 protein were shown,including leptomycin B resistance,inhibition of the type I interferon signaling,regulation of the viral mRNA translation and determining the composition of HSV-1 virions.