Recombination in SV40-infected cells: Viral DNA sequences at sites of circularization of transfecting linear DNA

ABSTRACT We have demonstrated previously that the adenovirus L1 52/55-kDa protein binds to the viral IVa2 protein in infected cells. The significance of this interaction was unclear, however, based on the known functions of these two proteins: the 52/55-kDa protein is required for viral DNA packaging, while the IVa2 protein is a transactivator of the major late promoter (MLP). In this report, we have attempted to elucidate a role for each of the two proteins in the other's known function. There is no apparent effect of the 52/55-kDa protein on the interaction of the IVa2 protein with the MLP. Surprisingly, however, we found that the IVa2 protein can interact with the adenoviral packaging signal and that this interaction involves DNA sequences that have previously been demonstrated to be required for packaging.

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Infectious linear DNA sequences replicating in simian virus 40-infected cells.

Journal of Virology ◽

10.1128/jvi.21.2.565-578.1977 ◽

1977 ◽

Vol 21 (2) ◽

pp. 565-578 ◽

Cited By ~ 6

Author(s):

P Gruss ◽

G Sauer

Keyword(s):

Dna Sequences ◽

Simian Virus 40 ◽

Simian Virus ◽

Linear Dna ◽

Infected Cells

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Intracellular forms of adenovirus DNA. V. Viral DNA sequences in hamster cells abortively infected and transformed with human adenovirus type 12.

Journal of Virology ◽

10.1128/jvi.20.2.373-383.1976 ◽

1976 ◽

Vol 20 (2) ◽

pp. 373-383 ◽

Cited By ~ 35

Author(s):

E Fanning ◽

W Doerfler

Keyword(s):

Dna Sequences ◽

Human Adenovirus ◽

Adenovirus Type ◽

Viral Dna ◽

Human Adenovirus Type 12

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Engagement of the Lysine-Specific Demethylase/HDAC1/CoREST/REST Complex by Herpes Simplex Virus 1

Journal of Virology ◽

10.1128/jvi.02515-08 ◽

2009 ◽

Vol 83 (9) ◽

pp. 4376-4385 ◽

Cited By ~ 44

Author(s):

Haidong Gu ◽

Bernard Roizman

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Nuclear Bodies ◽

Wild Type Virus ◽

Viral Dna ◽

Herpes Simplex Virus 1 ◽

Lysine Specific Demethylase ◽

Repressor Complex ◽

Infected Cells ◽

Simplex Virus

ABSTRACT Among the early events in herpes simplex virus 1 replication are localization of ICP0 in ND10 bodies and accumulation of viral DNA-protein complexes in structures abutting ND10. ICP0 degrades components of ND10 and blocks silencing of viral DNA, achieving the latter by dislodging HDAC1 or -2 from the lysine-specific demethylase 1 (LSD1)/CoREST/REST repressor complex. The role of this process is apparent from the observation that a dominant-negative CoREST protein compensates for the absence of ICP0 in a cell-dependent fashion. HDAC1 or -2 and the CoREST/REST complex are independently translocated to the nucleus once viral DNA synthesis begins. The focus of this report is twofold. First, we report that in infected cells, LSD1, a key component of the repressor complex, is partially degraded or remains stably associated with CoREST and is ultimately also translocated, in part, to the cytoplasm. Second, we examined the distribution of the components of the repressor complex and ICP8 early in infection in wild-type-virus- and ICP0 mutant virus-infected cells. The repressor component and ultimately ICP8 localize in structures that abut the ND10 nuclear bodies. There is no evidence that the two compartments fuse. We propose that ICP0 must dynamically interact with both compartments in order to accomplish its functions of degrading PML and SP100 and suppressing silencing of viral DNA through its interactions with CoREST. In turn, the remodeling of the viral DNA-protein complex enables recruitment of ICP8 and initiation of formation of replication compartments.

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Nucleolin Is Required for Efficient Nuclear Egress of Herpes Simplex Virus Type 1 Nucleocapsids

Journal of Virology ◽

10.1128/jvi.02007-09 ◽

2009 ◽

Vol 84 (4) ◽

pp. 2110-2121 ◽

Cited By ~ 29

Author(s):

Ken Sagou ◽

Masashi Uema ◽

Yasushi Kawaguchi

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Nuclear Membrane ◽

Herpes Simplex Virus Type ◽

Viral Dna ◽

Nuclear Egress ◽

Infected Cells ◽

Simplex Virus ◽

Hsv 1

ABSTRACT Herpesvirus nucleocapsids assemble in the nucleus and must cross the nuclear membrane for final assembly and maturation to form infectious progeny virions in the cytoplasm. It has been proposed that nucleocapsids enter the perinuclear space by budding through the inner nuclear membrane, and these enveloped nucleocapsids then fuse with the outer nuclear membrane to enter the cytoplasm. Little is known about the mechanism(s) for nuclear egress of herpesvirus nucleocapsids and, in particular, which, if any, cellular proteins are involved in the nuclear egress pathway. UL12 is an alkaline nuclease encoded by herpes simplex virus type 1 (HSV-1) and has been suggested to be involved in viral DNA maturation and nuclear egress of nucleocapsids. Using a live-cell imaging system to study cells infected by a recombinant HSV-1 expressing UL12 fused to a fluorescent protein, we observed the previously unreported nucleolar localization of UL12 in live infected cells and, using coimmunoprecipitation analyses, showed that UL12 formed a complex with nucleolin, a nucleolus marker, in infected cells. Knockdown of nucleolin in HSV-1-infected cells reduced capsid accumulation, as well as the amount of viral DNA resistant to staphylococcal nuclease in the cytoplasm, which represented encapsidated viral DNA, but had little effect on these viral components in the nucleus. These results indicated that nucleolin is a cellular factor required for efficient nuclear egress of HSV-1 nucleocapsids in infected cells.

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Transmission of Human T Cell Leukemia Virus Type I to Sheep: Antibody Profile and Detection of Viral DNA Sequences

AIDS Research and Human Retroviruses ◽

10.1089/aid.1996.12.1717 ◽

1996 ◽

Vol 12 (18) ◽

pp. 1717-1724 ◽

Cited By ~ 3

Author(s):

EDUARDO N. ESTEBAN ◽

MICHAEL P. SHERMAN ◽

BERNARD L. POIESZ ◽

ROBERT R. MARSHAK ◽

DAVID J. WATERS ◽

...

Keyword(s):

T Cell ◽

Virus Type ◽

Dna Sequences ◽

Leukemia Virus ◽

Type I ◽

Cell Leukemia ◽

Viral Dna ◽

Cell Leukemia Virus Type ◽

Human T Cell ◽

T Cell Leukemia Virus

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Integration of viral DNA sequences in cells transformed by adenovirus 2 or SV40

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1980.0144 ◽

1980 ◽

Vol 210 (1180) ◽

pp. 423-435 ◽

Cited By ~ 2

Keyword(s):

Cell Lines ◽

Dna Sequences ◽

Viral Genome ◽

Viral Dna ◽

Viral Genomes ◽

Viral Dnas ◽

Cellular Dna ◽

Viral Insertion ◽

Viral Sequences ◽

Heteroduplex Formation

We have cloned and propagated in prokaryotic vectors the viral DNA sequences that are integrated in a variety of cells transformed by adenovirus 2 or SV40. Analysis of the clones reveals that the viral DNA sequences sometimes are arranged in a simple fashion, collinear with the viral genome; in other cell lines there are complex arrangements of viral sequences in which tracts of the viral genome are inverted with respect to each other. In several cases the nucleotide sequences at the joints between cell and viral sequences have been determined: usually there is a sharp transition between cellular and viral DNAs. The viral sequences are integrated at different locations within the genomes of different cell lines; likewise there is no specific site on the viral genomes at which integration occurs. Sometimes the viral sequences are integrated within repetitive cellular DNA, and sometimes within unique sequences. In some cases there is evidence that the viral sequences along with the flanking cell DNA have been amplified after integration. The sequences that flank the viral insertion in the line of SV40-transformed rat cells known as 14B have been used as probes to isolate, from untransformed rat cells, clones that carry the region of the chromosome in which integration occurred. Analysis of the structure of these clones by restriction endonuclease digestion and heteroduplex formation shows that a rearrangement of cellular sequences has occurred, presumably as a consequence of integration.

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Cellular Zinc Finger Protein 622 Hinders Human Adenovirus Lytic Growth and Limits Binding of the Viral pVII Protein to Virus DNA

Journal of Virology ◽

10.1128/jvi.01628-18 ◽

2018 ◽

Vol 93 (3) ◽

Cited By ~ 2

Author(s):

Kwangchol Mun ◽

Tanel Punga

Keyword(s):

Life Cycle ◽

Zinc Finger ◽

Zinc Finger Protein ◽

Human Adenovirus ◽

Antiviral Protein ◽

Viral Dna ◽

Finger Protein ◽

Wide Range ◽

Infected Cells ◽

Cellular Zinc

ABSTRACTHuman adenovirus (HAdV) encodes a multifunctional DNA-binding protein pVII, which is involved in virus DNA packaging and extracellular immune signaling regulation. Although the pVII is an essential viral protein, its exact role in the virus life cycle and interplay with cellular proteins have remained to a large extent unclear. We have recently identified the cellular zinc finger protein 622 (ZNF622) as a potential pVII-interacting protein. In this study, we describe the functional consequences of the ZNF622-pVII interplay and the role of ZNF622 in the HAdV life cycle. ZNF622 protein expression increased, and it accumulated similarly to the pVII protein in the nuclei of virus-infected cells. The lack of the ZNF622 protein specifically increased pVII binding to viral DNA in the infected cells and elevated the pVII protein levels in the purified virions. In addition, ZNF622 knockout cells showed an increased cell lysis and enhanced accumulation of the infectious virus particles. Protein interaction studies revealed that ZNF622 forms a trimeric complex with the pVII protein and the cellular histone chaperon protein nucleophosmin 1 (NPM1). The integrity of this complex is important since ZNF622 mutations and NPM1 deficiency changed pVII ability to bind viral DNA. Collectively, our results implicate that ZNF622 may act as a cellular antiviral protein hindering lytic HAdV growth and limiting pVII protein binding to viral DNA.IMPORTANCEHuman adenoviruses (HAdVs) are common human pathogens causing a wide range of acute infections. To counteract viral pathogenicity, cells encode a variety of antiviral proteins and noncoding RNAs to block virus growth. In this study, we show that the cellular zinc finger protein 622 (ZNF622) interacts with an essential HAdV protein known as pVII. This mutual interaction limits pVII binding to viral DNA. Further, ZNF622 has a role in HAdV life cycle since the lack of ZNF622 correlates with increased lysis of the infected cells and accumulation of the infectious virions. Together, our study reveals a novel cellular antiviral protein ZNF622, which may impede lytic HAdV growth.

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The Conserved Carboxyl-Terminal Half of Herpes Simplex Virus Type 1 Regulatory Protein ICP27 Is Dispensable for Viral Growth in the Presence of Compensatory Mutations

Journal of Virology ◽

10.1128/jvi.74.16.7362-7374.2000 ◽

2000 ◽

Vol 74 (16) ◽

pp. 7362-7374 ◽

Cited By ~ 1

Author(s):

Scott M. Bunnell ◽

Stephen A. Rice

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Herpes Simplex Virus Type ◽

Vero Cells ◽

Terminal Portion ◽

Viral Dna ◽

Infected Cells ◽

Simplex Virus ◽

Hsv 1

ABSTRACT ICP27 is an essential herpes simplex virus type 1 (HSV-1) immediate-early protein that regulates viral gene expression by poorly characterized mechanisms. Previous data suggest that its carboxyl (C)-terminal portion is absolutely required for productive viral infection. In this study, we isolated M16R, a second-site revertant of a viral ICP27 C-terminal mutant. M16R harbors an intragenic reversion, as demonstrated by the fact that its cloned ICP27 allele can complement the growth of an HSV-1 ICP27 deletion mutant. DNA sequencing demonstrated that the intragenic reversion is a frameshift alteration in a homopolymeric run of C residues at codons 215 to 217. This results in the predicted expression of a truncated, 289-residue molecule bearing 72 novel C-terminal residues derived from the +1 reading frame. Consistent with this, M16R expresses an ICP27-related molecule of the predicted size in the nuclei of infected cells. Transfection-based viral complementation assays confirmed that the truncated, frameshifted protein can partially substitute for ICP27 in the context of viral infection. Surprisingly, its novel C-terminal residues are required for this activity. To see if the frameshift mutation is all that is required for M16R's viability, we re-engineered the M16R ICP27 allele and inserted it into a new viral background, creating the HSV-1 mutant M16exC. An additional mutant, exCd305, was constructed which possesses the frameshift in the context of an ICP27 gene with the C terminus deleted. We found that both M16exC and exCd305 are nonviable in Vero cells, suggesting that one or more extragenic mutations are also required for the viability of M16R. Consistent with this interpretation, we isolated two viable derivatives ofexCd305 which grow productively in Vero cells despite being incapable of encoding the C-terminal portion of ICP27. Studies of viral DNA synthesis in mutant-infected cells indicated that the truncated, frameshifted ICP27 protein can enhance viral DNA replication. In summary, our results demonstrate that the C-terminal portion of ICP27, conserved widely in herpesviruses and previously believed to be absolutely essential, is dispensable for HSV-1 lytic replication in the presence of compensatory genomic mutations.

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