Adenoviruses — Model for DNA Replication in Mammalian Cells — Role of Viral Proteins in Viral DNA Replication

DNA Synthesis ◽  
1978 ◽  
pp. 839-867
Author(s):  
M. Green ◽  
W. S. M. Wold
Keyword(s):  
Dna Replication ◽  
Mammalian Cells ◽  
Viral Proteins ◽  
Viral Dna ◽  
Viral Dna Replication

Polyomavirus-plasmid recombinants capable of replicating have an enhanced transforming potential

1983 ◽  
Vol 3 (9) ◽  
pp. 1670-1674
Author(s):  
W J Muller ◽  
M A Naujokas ◽  
J A Hassell
Keyword(s):  
Dna Replication ◽  
Mammalian Cells ◽  
T Antigen ◽  
Viral Gene ◽  
Large T Antigen ◽  
Viral Dna ◽  
Viral Dna Replication ◽  
Transfected Cells ◽  
Cis Acting ◽  
Viral Gene Product

The frequency of transformation of rodent fibroblasts by polyomavirus is enhanced by a viral gene product, large T-antigen. However, this effect of large T-antigen cannot be demonstrated with pBR322-cloned viral DNA. Recently, it was discovered that pBR322 contains cis-acting sequences inhibitory to DNA replication in mammalian cells. Because polyomavirus large T-antigen is required for viral DNA replication, we examined the possibility that our inability to demonstrate a requirement for large T-antigen in transformation with pBR322-cloned viral DNA was due to the failure of the chimeric DNA to replicate in the transfected cells. To this end we constructed polyomavirus recombinant molecules with a plasmid (pML-2) that lacks these "poison" sequences and measured their capacity to transform cells. Here we report that recombinant plasmids capable of replicating in the transfected cells transform these cells at frequencies approximately sixfold greater than their replication-defective counterparts.

scholarly journals Cellular DNA Ligase I Is Recruited to Cytoplasmic Vaccinia Virus Factories and Masks the Role of the Vaccinia Ligase in Viral DNA Replication

2009 ◽  
Vol 6 (6) ◽  
pp. 563-569 ◽  
Author(s):  
Nir Paran ◽  
Frank S. De Silva ◽  
Tatiana G. Senkevich ◽  
Bernard Moss
Keyword(s):  
Dna Replication ◽  
Vaccinia Virus ◽  
Dna Ligase ◽  
Viral Dna ◽  
Viral Dna Replication ◽  
Dna Ligase I ◽  
Cellular Dna

scholarly journals Polyomavirus-plasmid recombinants capable of replicating have an enhanced transforming potential.

1983 ◽  
Vol 3 (9) ◽  
pp. 1670-1674 ◽  
Author(s):  
W J Muller ◽  
M A Naujokas ◽  
J A Hassell
Keyword(s):  
Dna Replication ◽  
Mammalian Cells ◽  
T Antigen ◽  
Viral Gene ◽  
Large T Antigen ◽  
Viral Dna ◽  
Viral Dna Replication ◽  
Transfected Cells ◽  
Cis Acting ◽  
Viral Gene Product

The frequency of transformation of rodent fibroblasts by polyomavirus is enhanced by a viral gene product, large T-antigen. However, this effect of large T-antigen cannot be demonstrated with pBR322-cloned viral DNA. Recently, it was discovered that pBR322 contains cis-acting sequences inhibitory to DNA replication in mammalian cells. Because polyomavirus large T-antigen is required for viral DNA replication, we examined the possibility that our inability to demonstrate a requirement for large T-antigen in transformation with pBR322-cloned viral DNA was due to the failure of the chimeric DNA to replicate in the transfected cells. To this end we constructed polyomavirus recombinant molecules with a plasmid (pML-2) that lacks these "poison" sequences and measured their capacity to transform cells. Here we report that recombinant plasmids capable of replicating in the transfected cells transform these cells at frequencies approximately sixfold greater than their replication-defective counterparts.

scholarly journals Evidence Supporting a Role for TopBP1 and Brd4 in the Initiation but Not Continuation of Human Papillomavirus 16 E1/E2-Mediated DNA Replication

2015 ◽  
Vol 89 (9) ◽  
pp. 4980-4991 ◽  
Author(s):  
Elaine J. Gauson ◽  
Mary M. Donaldson ◽  
Edward S. Dornan ◽  
Xu Wang ◽  
Molly Bristol ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
Dna Replication ◽  
Viral Proteins ◽  
Future Generations ◽  
Cellular Proteins ◽  
Origin Of Replication ◽  
Viral Dna ◽  
Viral Origin ◽  
Viral Dna Replication ◽  
Human Papillomavirus 16

ABSTRACTTo replicate the double-stranded human papillomavirus 16 (HPV16) DNA genome, viral proteins E1 and E2 associate with the viral origin of replication, and E2 can also regulate transcription from adjacent promoters. E2 interacts with host proteins in order to regulate both transcription and replication; TopBP1 and Brd4 are cellular proteins that interact with HPV16 E2. Previous work with E2 mutants demonstrated the Brd4 requirement for the transactivation properties of E2, while TopBP1 is required for DNA replication induced by E2 from the viral origin of replication in association with E1. More-recent studies have also implicated Brd4 in the regulation of DNA replication by E2 and E1. Here, we demonstrate that both TopBP1 and Brd4 are present at the viral origin of replication and that interaction with E2 is required for optimal initiation of DNA replication. Both cellular proteins are present in E1-E2-containing nuclear foci, and the viral origin of replication is required for the efficient formation of these foci. Short hairpin RNA (shRNA) against either TopBP1 or Brd4 destroys the E1-E2 nuclear bodies but has no effect on E1-E2-mediated levels of DNA replication. An E2 mutation in the context of the complete HPV16 genome that compromises Brd4 interaction fails to efficiently establish episomes in primary human keratinocytes. Overall, the results suggest that interactions between TopBP1 and E2 and between Brd4 and E2 are required to correctly initiate DNA replication but are not required for continuing DNA replication, which may be mediated by alternative processes such as rolling circle amplification and/or homologous recombination.IMPORTANCEHuman papillomavirus 16 (HPV16) is causative in many human cancers, including cervical and head and neck cancers, and is responsible for the annual deaths of hundreds of thousands of people worldwide. The current vaccine will save lives in future generations, but antivirals targeting HPV16 are required for the alleviation of disease burden on the current, and future, generations. Targeting viral DNA replication that is mediated by two viral proteins, E1 and E2, in association with cellular proteins such as TopBP1 and Brd4 would have therapeutic benefits. This report suggests a role for these cellular proteins in the initiation of viral DNA replication by HPV16 E1-E2 but not for continuing replication. This is important if viral replication is to be effectively targeted; we need to understand the viral and cellular proteins required at each phase of viral DNA replication so that it can be effectively disrupted.

Role of bacteriophage M13 gene 2 in viral DNA replication

1972 ◽  
Vol 72 (1) ◽  
pp. 37-49 ◽  
Author(s):  
Norm S.-C. Lin ◽  
David Pratt
Keyword(s):  
Dna Replication ◽  
Viral Dna ◽  
Viral Dna Replication ◽  
Bacteriophage M13

Immunological characterization of the role of adenovirus terminal protein in viral DNA replication

Virology ◽  
1983 ◽  
Vol 131 (2) ◽  
pp. 287-295 ◽  
Author(s):  
A.W.M. Rijnders ◽  
B.G.M. Van Bergen ◽  
P.C. Van Der Vliet ◽  
J.S. Sussenbach
Keyword(s):  
Dna Replication ◽  
Viral Dna ◽  
Terminal Protein ◽  
Viral Dna Replication ◽  
Immunological Characterization

scholarly journals Kaposi's Sarcoma-Associated Herpesvirus-Encoded Protein Kinase and Its Interaction with K-bZIP

2006 ◽  
Vol 81 (3) ◽  
pp. 1072-1082 ◽  
Author(s):  
Yoshihiro Izumiya ◽  
Chie Izumiya ◽  
Albert Van Geelen ◽  
Don-Hong Wang ◽  
Kit S. Lam ◽  
...  
Keyword(s):  
Dna Replication ◽  
Protein Kinase ◽  
Viral Protein ◽  
Kaposi's Sarcoma ◽  
Kaposi’S Sarcoma ◽  
Viral Transcription ◽  
Viral Dna ◽  
Viral Dna Replication ◽  
Kaposi’S Sarcoma Associated Herpesvirus

ABSTRACT The oncogenic herpesvirus, Kaposi's sarcoma-associated herpesvirus, also identified as human herpesvirus 8, contains genes producing proteins that control transcription and influence cell signaling. Open reading frame 36 (ORF36) of this virus encodes a serine/threonine protein kinase, which is designated the viral protein kinase (vPK). Our recent efforts to elucidate the role of vPK in the viral life cycle have focused on identifying viral protein substrates and determining the effects of vPK-mediated phosphorylation on specific steps in viral replication. The vPK gene was transcribed into 4.2-kb and 3.6-kb mRNAs during the early and late phases of viral reactivation. vPK is colocalized with viral DNA replication/transcription compartments as marked by a polymerase processivity factor, and K-bZIP, a protein known to bind the viral DNA replication origin (Ori-Lyt) and to regulate viral transcription. The vPK physically associated with and strongly phosphorylated K-bZIP at threonine 111, a site also recognized by the cyclin-dependent kinase Cdk2. Both K-bZIP and vPK were corecruited to viral promoters targeted by K-bZIP as well as to the Ori-Lyt region. Phosphorylation of K-bZIP by vPK had a negative impact on K-bZIP transcription repression activity. The extent of posttranslational modification of K-bZIP by sumoylation, a process that influences its repression function, was decreased by vPK phosphorylation at threonine 111. Our data thus identify a new role of vPK as a modulator of viral transcription.

scholarly journals Herpes Simplex Virus DNA Synthesis Is Not a Decisive Regulatory Event in the Initiation of Lytic Viral Protein Expression in Neurons In Vivo during Primary Infection or Reactivation from Latency

2006 ◽  
Vol 80 (1) ◽  
pp. 38-50 ◽  
Author(s):  
N. M. Sawtell ◽  
R. L. Thompson ◽  
R. L. Haas
Keyword(s):  
Gene Expression ◽  
Dna Replication ◽  
Dna Synthesis ◽  
Sensory Neurons ◽  
Viral Proteins ◽  
Lytic Cycle ◽  
Viral Dna ◽  
Viral Dna Replication ◽  
Simplex Virus

ABSTRACT The herpes simplex virus genome can enter a repressed transcriptional state (latency) in sensory neurons of the host nervous system. Although reduced permissiveness of the neuronal environment is widely accepted as a causal factor, the molecular pathway(s) directing and maintaining the viral genome in the latent state remains undefined. Over the past decade, the field has been strongly influenced by the observations of Kosz-Vnenchak et al., which have been interpreted to indicate that, in sensory neurons in vivo, a critical level of viral DNA synthesis within the neuron is required for sufficient viral immediate-early (IE) and early (E) gene expression (M. Kosz-Vnenchak, J. Jacobson, D. M. Coen, and D. M. Knipe, J. Virol. 67:5383-5393, 1993). The levels of IE and E genes are, in turn, thought to regulate the decision to enter the lytic cycle or latency. We have reexamined this issue using new strategies for in situ detection and quantification of viral gene expression in whole tissues. Our results using thymidine kinase-null and rescued mutants as well as wild-type strains in conjunction with viral DNA synthesis blockers demonstrate that (i) despite inhibition of viral DNA replication, many neurons express lytic viral proteins, including IE proteins, during acute infection in the ganglion; (ii) at early times postinoculation, the number of neurons expressing viral proteins in the ganglion is not reduced by inhibition of viral DNA replication; and (iii) following a reactivation stimulus, the numbers of neurons and apparent levels of lytic viral proteins, including IE proteins, are not reduced by inhibition of viral DNA replication. We conclude that viral DNA replication in the neuron per se does not regulate IE gene expression or entry into the lytic cycle.

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