Download or read book The Role of the Cytoplasmic Domain of Herpes Simplex Virus Type 1 Glycoprotein C in Membrane Anchoring and Protein Processing written by Anne M. Skoff and published by . This book was released on 1993 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Human Herpesviruses written by Ann Arvin and published by Cambridge University Press. This book was released on 2007-08-16 with total page 1325 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive account of the human herpesviruses provides an encyclopedic overview of their basic virology and clinical manifestations. This group of viruses includes human simplex type 1 and 2, Epstein–Barr virus, Kaposi's Sarcoma-associated herpesvirus, cytomegalovirus, HHV6A, 6B and 7, and varicella-zoster virus. The viral diseases and cancers they cause are significant and often recurrent. Their prevalence in the developed world accounts for a major burden of disease, and as a result there is a great deal of research into the pathophysiology of infection and immunobiology. Another important area covered within this volume concerns antiviral therapy and the development of vaccines. All these aspects are covered in depth, both scientifically and in terms of clinical guidelines for patient care. The text is illustrated generously throughout and is fully referenced to the latest research and developments.
Download or read book Glycoprotein M and ESCRT in Herpes Simplex Virus Type 1 Assembly written by Yudan Ren and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Herpes simplex virus type 1 (HSV-1) has a large linear double-stranded DNA genome in an icosahedral capsid shell, a cell-derived lipid envelope and a proteinaceous tegument layer. There are over fifty viral proteins and many host proteins identified in HSV-1 virions. The final formation of mature virus particles requires the membrane wrapping of tegumented capsids in the cytoplasm, a process termed secondary envelopment. This process involves the coordination of numerous viral and cellular proteins and results in double-membrane structures with enveloped virions contained within cellular vesicles. Mature viruses are then released through the fusion of these virion-containing vesicles and plasma membranes. This thesis describes investigation into the functions of viral glycoprotein M (gM) and the cellular Endosomal Sorting Complexes Required for Transport (ESCRT) in secondary envelopment. Firstly, it has been reported that gH/L can be efficiently internalised and targeted to the TGN by the co-expression of gM in transfection assays. In order to examine the role of gM in guiding the localisation of viral proteins in infected cells, a HSV-1 gM deletion virus (∆gM), and its revertant virus were constructed. The major phenotype demonstrated was that the absence of gM caused the internalisation of cell surface gH/L to be inhibited and higher levels of gH/L to be observed on the cell surface. Further, lower levels of gH/L were detected in purified ∆gM virions, which was in agreement with the delayed entry kinetics, smaller plaque sizes and greater replication deficits at low multiplicity of infection observed in ∆gM infected cells. Over all the results presented in this thesis demonstrate that in infected cells the efficient incorporation of gH/L into virions relies on the function of gM in HSV-1. Secondly, during HSV-1 secondary envelopment the budding and scission of the viral envelope from the host membrane share topological similarities with the formation of intraluminal vesicle in multivesicular bodies, retrovirus budding, and abscission at the end of cytokinesis, processes that require the cellular ESCRT machinery. There are four multiprotein ESCRT complexes and many associated proteins involved in their regulation. It has been previously shown that the ESCRT-III complex and a functional ATPase VPS4 are required for HSV-1 secondary envelopment, but different from the strategy utilised by HIV-1, the recruitment of ESCRT during HSV-1 infection is independent of TSG101 and/or ALIX. Data presented in this thesis demonstrate that CHMP4A/B/C proteins of the ESCRT-III complex are specifically crucial for HSV-1 secondary envelopment. Simultaneous depletion of CHMP4A/B/C proteins significantly inhibited HSV-1 replication. Ultrastructure analysis revealed that there were virtually no extracellular virions in CHMP4A/B/C depleted samples while more free capsids were observed in the cytoplasm, although the nuclear capsids and primary envelopment events appeared to be normal. In order to identify interactions between HSV-1 and ESCRT proteins, 22 HSV-1 tegument proteins were cloned and tested against a panel of ESCRT and ESCRT-associated proteins in yeast two-hydrid assays. Analysis of positive hits from yeast two-hybrid interaction screens using GST pull-down, co-immunoprecipitation and protein co-localisation assays have validated interactions of pUL47 with CC2D1A/1B, CIN85, CHMP6 and ALIX, pUL46 and pUL49 with CC2D1A/1B and CIN85, and pUL16 with CC2D1A/1B. Furthermore, the newly identified ESCRT associated proteins CC2D1A and CC2D1B have been detected in purified virions. The role of the identified ESCRT proteins in HSV-1 replication has been investigated using siRNA depletion. Unfortunately siRNA depletions of the various ESCRT candidates individually or in combinations did not show any significant effect on HSV-1 replication. Overall these data suggest that unlike HIV and other retroviruses, HSV-1 has evolved multiple parallel pathways to hijack the ESCRT machinery to facilitate its replication, particularly, through the interactions that lead directly to the recruitment of CHMP4A/B/C proteins. Disruption of some of these pathways did not prevent HSV-1 replication in tissue culture, suggesting any one potential pathway is sufficient for ESCRT recruitment to sites of HSV-1 assembly.
Download or read book Gene Delivery to Mammalian Cells written by William C. Heiser and published by Springer Science & Business Media. This book was released on 2008-02-02 with total page 561 pages. Available in PDF, EPUB and Kindle. Book excerpt: The efficiency of delivering DNA into mammalian cells has increased t- mendously since DEAE dextran was first shown to be capable of enhancing transfer of RNA into mammalian cells in culture. Not only have other chemical methods been developed and refined, but also very efficient physical and viral delivery methods have been established. The technique of introducing DNA into cells has developed from transfecting tissue culture cells to delivering DNA to specific cell types and organs in vivo. Moreover, two important areas of biology—assessment of gene function and gene therapy—require succe- ful DNA delivery to cells, driving the practical need to increase the efficiency and efficacy of gene transfer both in vitro and in vivo. TM These two volumes of the Methods in Molecular Biology series, Gene Del- ery to Mammalian Cells, are designed as a compendium of those techniques that have proven most useful in the expanding field of gene transfer in mammalian cells. It is intended that these volumes will provide a thorough background on chemical, physical, and viral methods of gene delivery, a synopsis of the myriad techniques currently available to introduce genes into mammalian cells, as well as a practical guide on how to accomplish this. It is my expectation that it will be useful to the novice in the field as well as to the scientist with expertise in gene delivery.
Download or read book A Structural and Functional Analysis of Herpes Simplex Virus Type 1 Glycoprotein L an Essential Component of the Viral Fusogenic Complex written by Michael J. Novotny and published by . This book was released on 1996 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Herpes Simplex Virus Type 1 UL31 and UL34 Proteins and Their Roles in Viral Envelopment at the Inner Nuclear Membrane written by Li Liang and published by . This book was released on 2005 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Functional Analysis of the Transmembrane Domain and Cytoplasmic Tail of Herpes Simplex Virus Type 1 Glycoprotein H written by A. Harman and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparative Roles of Herpes Simplex Virus Type 1 HSV 1 Glycoproteins in Cytoplasmic Virion Egress written by Hyun Cheol Lee and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1993 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gene and Cell Therapy written by Nancy Smyth Templeton and published by CRC Press. This book was released on 2003-12-17 with total page 894 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reference is completely revised and expanded to reflect the most critical studies, controversies, and technologies impacting the medical field, including probing research on lentivirus, gutless adenovirus, bacterial and baculovirus vectors, retargeted viral vectors, in vivo electroporation, in vitro and in vivo gene detection systems, and all inducible gene expression systems. Scrutinizing every tool, technology, and issue impacting the future of gene and cell research, it is specifically written and organized for laymen, scholars, and specialists from varying backgrounds and disciplines to understand the current status of gene and cell therapy and anticipate future developments in the field.
Download or read book Structural and Functional Study of Bovine Herpesvirus 1 Glycoprotein B in the Interaction with Madin Darby Bovine Kidney Cells written by and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Entry of herpesviruses is mediated by the interactions between viral glycoproteins and cellular receptors. Among these glycoproteins, gB plays an important role. In this study, my major focus was to study gB's functions in the virus entry process and the structural requirements for gB to conduct its functions. The virus model in my study is bovine herpesvirus 1 (BHV-1), a member of the alphaherpesviruses. BHV-1 gB is a type I integral membrane protein with a potential transmembrane anchor at the C-terminal region. A cleavage site in the middle divides this molecule into two subunits, gBb and gBc. In this study, a truncated gB, gBt (residues 1 to 763), and N-terminal subunit, gBb (residues 1 to 505), were first expressed under the control of the bovine heat-shock protein 70A (hsp70A) gene promoter in stably transfected Madin Darby bovine kidney (MDBK) cells. Both forms of gB were secreted into the medium with apparent molecular weights as anticipated, and they were reactive to all gB-specific monoclonal antibodies used in this study. Affinity-purified gBt and gBb were able to elicit antibody responses in mice to an extent comparable to those induced by authentic gB. These results suggest that gBt and gBb retain the structural and antigenic properties of authentic gB. Furthermore, the intracellular processing of gBt and gBb was similar to that of authentic gB in virus-infected cells. Finally, gBt was proteolytically cleaved after conversion of the high mannose-containing precursor to the mature form. These truncated gBs that were prepared served as reagents for the core of my studies. BHV-I gB can bind to heparin sulfate (HS) and another non-HS receptor on MDBK cells. We assume that high-affinity binding to the non-HS receptor is important for BHV-1 infectivity. BHV-1 gB forms dimers in infected cells and in virions, and its dimerization domain may be located between residues 506 to 763. The cytoplasmic domain of BHV-1 gB is important for the existence of the high-aff.
Download or read book Contributions of Amphipathic Helices and the Cytoplasmic Tail of the Herpes Simplex Virus Type 2 Glycoprotein B to Its Role in Membrane Fusion written by Daniel David Norton and published by . This book was released on 2000 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cell Biology of Herpes Viruses written by Klaus Osterrieder and published by Springer. This book was released on 2017-05-20 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herpes viruses are widely distributed in nature, causing disease in organisms as diverse as bivalves and primates, including humans. Each virus appears to have established a long-standing relationship with its host, and the viruses have the ability to manipulate and control the metabolism of host cells, as well as innate and adaptive antiviral immune responses. Herpes viruses maintain themselves within hosts in a latent state resulting in virus persistence for years – usually for the life span of the hosts. Herpes viruses comprise a large number of pathogens with diverse cellular targets and biological consequences of infection. What they have in common is their structure and the fact that they establish a dormant (latent) infection in their hosts that usually persists for life. The reviews here will highlight the general principles of herpes virus infection, with equal attention to overall principle and important difference. Also, the cell type- and life-style dependent differences in the establishment and maintenance of virus persistence will be covered.
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1997 with total page 1860 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Herpes Simplex Virus Type 1 written by Kari Lynn Roberts and published by . This book was released on 2011 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herpes simplex virus type 1 (HSV-1) replicates in the nucleus and buds through the nuclear membrane to access the cytosol and complete the maturation process. The HSV-1 protein pUL31, along with its binding partner, pUL34, has been previously shown to be required for nucleocapsids to successfully bud through the nuclear membrane. pUL31 is also required for efficient viral DNA synthesis and packaging. After the HSV-1 exits the nucleus, the capsid acquires several accessory proteins (tegument) and finally a mature envelope by budding into vesicles of the trans-Golgi network (TGN). These virion-laden vesicles traffic toward the cell periphery and through cortical actin until ultimately the virion is secreted upon fusion of the TGN vesicle with the plasma membrane. The data presented here reveals new roles for pUL31, as cells infected with a UL31-null virus were delayed for viral gene expression as well as activation of NF[kappa]B and c-Jun N-terminal kinase (JNK) in multiple cell lines. At least one representative from each kinetic class of viral genes was examined at various times post infection. The protein expression defects were not caused by a failure to enter cells, was not rescued by ICP27 expressed in trans and correlated with NF[kappa]B activation. The data shows that these defects were not observed in the absence of the pUL31 binding partner, pUL34, and that while most pUL31 is expressed at late times post infection, low levels are detectable as early as 2 hours post infection. Data presented in this work also demonstrates a role for the actin motor myosin Va in the secretion of HSV-1 virions. Expression of two isoforms of dominant negative myosin Va (DN-myoVa) decreased virion secretion by 5075% as well as significantly decreased surface expression of viral glycoproteins B, M and D. DN-myoVa colocalized with TGN markers and the conformation of native myosin Va in infected cells was altered by 4 hours post infection. These data suggest that myosin Va is involved in the egress of virion-laden TGN vesicles as they transit through cortical actin toward the plasma membrane.
Download or read book Newly Identified Roles of Glycoprotein C in Herpes Simplex Virus Infectivity written by Tri Komala Sari and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herpes simplex virus (HSV) infections are mainly asymptomatic, but are ubiquitous in the adult population, and can be fatal in individuals with suppressed immune systems. Prophylactic and treatment measures have not been sufficient to stop disease dissemination. HSV expresses at least 12 different glycoproteins and utilizes multiple entry pathways to infect cells. This combined with its ability to establish latent infection and evade immune responses have contributed to the challenges in developing effective control measures. HSV uses the concerted action of essential glycoproteins B, D, and H/L to execute entry. HSV carries more than a dozen surface glycoproteins, and this may pose evolutionary advantages. It is likely that HSV uses specific surface glycoprotein(s) to effectively enter one pathway, but not the other. Here we report novel roles of glycoprotein C in HSV infectivity. gB from HSV-1 fully deleted for the gC gene undergoes low-pH induced antigenic changes at a pH that is 0.4-0.6 units lower than wild type. Moreover, gC-null mutant HSV exits cellular endosomes at time points 10-20 min later than wild type, suggesting that gB present in gC-null HSV fuses with a more acidic (later) endosome. We also report for the first time, low-pH antigenic changes in domain II of HSV gB. Although gC plays a role in gB antigenic changes, its absence does not affect gB oligomeric changes nor reversibility of conformational changes under conditions tested. The threshold for reversibility of gB conformational changes in wild type and gC-null HSV is shown to be around pH 5.6. This suggests that at this pH gB exists at an equilibrium of pre- and post-fusion forms. We also tested the ability of gB antibodies to block HSV infectivity in the absence of gC. We found that gC-null HSV is significantly more sensitive to neutralization by gB antibodies. The level and composition of HSV glycoproteins in wild type and gC-null mutant are similar. Interestingly, reactivity of gB antibodies with gC-null virus is greater than wild type. Control gE-null HSV is not more sensitive to neutralization by gB antibodies. Together our results demonstrate newly identified functional interactions between HSV gC and gB.
Download or read book Interactions Between the Tegument Proteins UL11 and UL16 and the Glycoprotein E of Herpes Simplex Virus written by Pei-Chun Yeh and published by . This book was released on 2009 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: The herpesvirus tegument region present between the virion envelope and the nucleocapsid contains more than 20 different virus-encoded proteins. The process of tegument assembly and final envelopment has been unfoldeding over the past few decades. It is thought that a few tegument proteins are added to the capsid in the nucleus, whereas most of them are acquired after entering the cytoplasm or traveling to the site of final envelopment at the trans-Golgi network. Overall, the research presented in this dissertation provides insights into the molecular mechanism of protein-protein interactions that may be involved in (or contribute to) assembly and maturation of herpes simplex virus type 1 (HSV-1). The UL11 (membrane-bound) and UL16 (capsid-associated) tegument proteins are conserved among all herpesviruses, and interaction between the two has been implicated in linking the viral capsid, tegument, and membrane during final envelopment process. Both in transfected and virus-infected cells, a subpopulation of the UL11 protein was found associated with detergent-resistant membranes via modifications with two fatty- acid chains (myristate and palmitate). UL11 can directly interact with UL16 in a manner dependent on the acidic cluster and leucine-isoleucine motifs of UL11. And, N-ethylmaleimide-modified UL16 was found to be incapable of binding UL11, suggesting that free cysteines in UL16 somehow play a role in the interaction. UL16 is stably associated with cytoplasmic capsids isolated from infected cells. In response to initial attachment of virus to the cell surface, an 'outside-in' signal is transmitted across the virion membrane, and as a result, UL16 is dissociated from the capsid. The mechanism by which the signal is sent to UL16 remains unclear but seems likely to be mediated by the glycoproteins on the virion envelope. A GST chimera bearing the cytoplasmic tail of glycoprotein E (gE. CT) was found to be capable of binding UL16 expressed in mammalian or insect cells. To better understand the molecular mechanism of this signaling process, the interaction network emanating from UL16 was investigated. In addition, previously using a GST pull-down assay, it was observed that UL16 interacts with virus-specific proteins from HSV- and PRV-infected cell lysates, providing evidence that UL16 is present in protein complexes. To characterize native complexes that contain UL16, a recombinant virus was constructed expressing a tagged derivative. Using the combination of tandem affinity purification and mass spectrometry analysis, we identified gE to be present in the complexes isolated from infected cells. The UL16-gE interaction was confirmed in co-immunoprecipitation assays with infected cell lysates. Moreover, mutational analyses of gE. CT have suggested that in infected cells UL16 may interact with gE. CT in both UL11-dependent and -independent manners. Based on all available data, we hypothesize that UL11, UL16, and gE may form a tripartite complex which plays a role in multiple aspects of the virus life cycle, including signaling events during virus attachment, virion maturation, or cell-to-cell spread. Collectively, our research focused on the protein-protein network has built a foundation for future studies, and also advanced our current knowledge of herpesvirus replication.
