Download or read book Characterization of the Herpes Simplex Virus 1 DNA Polymerase and Its Interaction with UL42 Protein and ICP8 and Mutational Analysis of a Viral Origin of Replication written by Thomas R. Hernandez and published by . This book was released on 1993 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Functional Significance of the Physical Interaction Between the Herpes Simplex Virus Type 1 Origin binding Protein UL9 and the DNA Polymerase Processivity Factor UL42 written by Kelly S. Trego and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The origin (ori)-binding protein of herpes simplex virus type 1 (HSV-1), encoded by the UL9 open-reading frame, has been shown to physically interact with a number of cellular and viral proteins, including three HSV-1 proteins (ICP8, UL42, and UL8) essential for ori-dependent DNA replication. In this report, it is demonstrated for the first time that the DNA polymerase processivity factor, UL42 protein, provides accessory function to the UL9 protein, by enhancing the 3' to 5' helicase activity of UL9 on partially duplex non-specific DNA substrates. UL42 fails to enhance the unwinding activity of a non-cognate helicase, suggesting enhancement of unwinding requires the physical interaction between UL42 and UL9. UL42 increases the steady-state rate for unwinding a 23/38-mer by UL9, but only at limiting UL9 concentrations, consistent with a role in increasing the affinity of UL9 for DNA. Optimum enhancement of unwinding was observed at UL42:UL9 molecular ratios of 4:1, although enhancement was reduced when high ratios of UL42:DNA were present. Under the assay conditions employed, UL42 did not alter the rate of dissociation of UL9 from the DNA substrate. UL42 also did not alter the requirement or time for an assembly/conformational change step, regardless of whether it was added to DNA prior to or at the same time as UL9, or after steady-state unwinding by UL9 alone had been achieved. Thus, the increased affinity of UL9 for DNA most likely is the result of an increase in the association rate constant for binding of UL9 to DNA, and explains why helicase enhancement is observed only at subsaturating concentrations of UL9 with respect to DNA. Consistent with this interpretation are results which demonstrate that UL42 also enhances the ATPase activity of UL9 on single-strand and partially duplex DNA substrates when UL9 is limiting. In contrast, ICP8 enhances unwinding at both saturating and subsaturating UL9 concentrations, and reduces or eliminates the lag period. The different means by which ICP8 and UL42 enhance activities of UL9 suggest that these two members of the presumed functional replisome may act synergistically on UL9 to effect initiation of HSV-1 DNA replication in vivo.
Download or read book Further Characterization of the UL37 Protein of Herpes Simplex Virus Type 1 and Its Interaction with ICP8 the Major DNA binding Protein of Herpes Simplex Virus written by Allen G. Albright and published by . This book was released on 1994 with total page 222 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 Herpes Simplex Virus 1 DNA Packaging written by Ying Fan and published by . This book was released on 1997 with total page 192 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 1994 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Identification and Characterization of the UL37 Protein of Herpes Simplex Virus Type 1 and Demonstration that it Interacts with ICP8 the Major DNA Binding Protein of Herpes Simplex Virus written by Lisa S. G. Shelton and published by . This book was released on 1992 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1993 with total page 1488 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1993 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Isolation of Host Proteins Involved in Herpes Simplex Virus Type 1 DNA Synthesis written by Whitney Cogswell and published by . This book was released on 2008 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Herpes simplex virus type 1 (HSV-1) is the prototypic member of a large family of viruses known as Herpesviridae. Herpesviruses possess a double-stranded DNA genome and infect a broad range of species. In addition to HSV-1, there are seven other herpesviruses that are known to infect humans. Although antiviral treatment is available for HSV infections, there are few or no options for treatment of infections by other herpesviruses. One of the best targets for development of new antivirals is the viral DNA replication apparatus. HSV-1 encodes for seven proteins directly involved in viral DNA replication. However, no HSV-1 origin-dependent DNA replication has been reconstituted in vitro using purified viral proteins. It is hypothesized that proteins (host and/or viral) in addition to the seven known viral DNA replication proteins are involved in viral DNA replication in vivo. Moreover, it is predicted that such proteins would interact with one or more of the viral DNA replication proteins. In an effort to identify interacting host proteins, co-immunoprecipitation analysis was performed using antibodies specific for an essential HSV DNA replication protein, UL42, the polymerase processivity factor. Extracts from infected and mock-infected cells were immunoprecipitated with the UL42 antibody. UL42, and all that is bound to it, bind to the antibody which binds to the Protein G agarose matrix. Those proteins that are specifically pulled down from infected cell extracts, but not from mock-infected extracts, were to be identified by mass-spectrometry. The immunoprecipitates were analyzed following separation on denaturing polyacrylamide gels. Gels were silver-stained or analyzed for the presence of UL42 using a Western blot. Conditions were adjusted to optimize the amount of UL42 immunoprecipitated, but UL42 could not be immunoprecipitated quantitatively. Following immunoprecipitation under optimum conditions, no differences were observed between the proteins pulled-down from mock- or infected-cell extracts. Due to the poor ability of the antibody to pull-down UL42, a second approach was employed. A histidine-tagged version of UL42 was purified using a nickel chelating column and then mixed with infected or mock-infected cell extracts. Those proteins that specifically interact with his-UL42 were expected to bind to a nickel column. However, nonspecific interactions with the matrix were observed and prevented identification of proteins by mass-spectrometry.
Download or read book The Role of the Associated 3 to 5 Exonuclease Activity and Processivity Factor UL42 of Herpes Simplex Virus Type 1 DNA Polymerase on the Fidelity of DNA Replication written by Liping Song and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Herpes simplex virus type 1 (HSV-1) DNA polymerase (pol) has an associated 32 to 52 exonuclease (exo) activity that plays an important role in maintaining the fidelity of DNA replication and viability of the virus. To assess the functional significance of the exo activity, the aspects of fidelity and translesion DNA synthesis affected by HSV-1 pol deficient in this exo activity (D368A) were examined and compared with those of wild-type pol. Because HSV-1 pol forms a stable heterodimer with UL42, a protein that stimulates the polymerizing activity and increases the processivity of pol, the impact of UL42 on fidelity was also evaluated. Pre-steady-state kinetic analysis revealed that the D368A mutation destroyed exo activity without significantly altering the inherent polymerization function. It was demonstrated that both wild-type and mutant pols could selectively incorporate correct vs. incorrect nucleotides, and exo activity enhanced nucleotide selectivity by roughly an order of magnitude under steady-state conditions. However, the primary effect of exo activity on fidelity was manifested during processive DNA synthesis, because it functioned to remove incorporated mismatches, the latter which impeded the extension ability of pol, particularly in the presence of UL42 processivity factor. UL42 did not alter the pre-steady-state rate constants for correct nucleotide incorporation, misincorporation, translocation, or nucleotide excision. However, UL42 decreased dissociation of pol from DNA, which not only made the enzyme more processive but also allowed enough time to excise replication errors. Lesions, such as abasic (AP) sites, also impeded extension beyond the sites, although both HSV-1 wild-type and exo-deficient pols could incorporate dATP opposite the AP site with reduced efficiencies compared to that for normal DNA synthesis. The exo activity facilitated sensing of the lesion through increased excision rate, thereby preventing extension through repeated incorporation and excision events. Taken together, the results of this study suggest that the associated exo activity of HSV-1 pol coordinates with the polymerizing activity by partitioning the primer terminus between the exo and polymerizing sites to proofread errors and prevent translesion synthesis, ultimately increasing the fidelity of HSV-1 DNA synthesis.
Download or read book Annual Commencement written by Stanford University and published by . This book was released on 1992 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biological Agricultural Index written by and published by . This book was released on 1993 with total page 2728 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Viral Genome Replication written by Craig E. Cameron and published by Springer Science & Business Media. This book was released on 2009-05-28 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the first comprehensive review of viral genome replication strategies, emphasizing not only pathways and regulation but also the structure-function, mechanism, and inhibition of proteins and enzymes required for this process.
Download or read book DNA Replication in Eukaryotic Cells written by Melvin L. DePamphilis and published by CSHL Press. This book was released on 1996 with total page 1080 pages. Available in PDF, EPUB and Kindle. Book excerpt: National Institutes of Health. Cold Spring Harbor Monograph, Volume 31 Extensive text on the replication of DNA, specifically in eukaryotic cells, for researchers. 68 contributors, 54 U.S.
Download or read book Encyclopedia of Virology written by and published by Academic Press. This book was released on 2021-02-24 with total page 4109 pages. Available in PDF, EPUB and Kindle. Book excerpt: Encyclopedia of Virology, Fourth Edition, Five Volume Set builds on the solid foundation laid by the previous editions, expanding its reach with new and timely topics. In five volumes, the work provides comprehensive coverage of the whole virosphere, making this a unique resource. Content explores viruses present in the environment and the pathogenic viruses of humans, animals, plants and microorganisms. Key areas and concepts concerning virus classification, structure, epidemiology, pathogenesis, diagnosis, treatment and prevention are discussed, guiding the reader through chapters that are presented at an accessible level, and include further readings for those needing more specific information. More than ever now, with the Covid19 pandemic, we are seeing the huge impact viruses have on our life and society. This encyclopedia is a must-have resource for scientists and practitioners, and a great source of information for the wider public. Offers students and researchers a one-stop shop for information on virology not easily available elsewhere Fills a critical gap of information in a field that has seen significant progress in recent years Authored and edited by recognized experts in the field, with a range of different expertise, thus ensuring a high-quality standard
Download or read book Essential Human Virology written by Jennifer Louten and published by Academic Press. This book was released on 2022-05-28 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential Human Virology, Second Edition focuses on the structure and classification of viruses, virus transmission and virus replication strategies based upon type of viral nucleic acid. Several chapters focus on notable and recognizable viruses and the diseases caused by them, including influenza, HIV, hepatitis viruses, poliovirus, herpesviruses and emerging and dangerous viruses. Additionally, how viruses cause disease (pathogenesis) is highlighted, along with discussions on immune response to viruses, vaccines, anti-viral drugs, gene therapy, the beneficial uses of viruses, research laboratory assays and viral diagnosis assays. Fully revised and updated with new chapters on coronaviruses, nonliving infectious agents, and notable non-human viruses, the book provides students with a solid foundation in virology. - Focuses on human diseases and the cellular pathology that viruses cause - Highlights current and cutting-edge technology and associated issues - Presents real case studies and current news highlights in each chapter - Features dynamic illustrations, chapter assessment questions, key terms, and a summary of concepts, as well as an instructor website with lecture slides, a test bank and recommended activities - Updated and revised, with new chapters on coronaviruses, nonliving infectious agents, and notable non-human viruses
