Interaction of the Human Papillomavirus E1 Helicase with UAF1-USP1 Promotes Unidirectional Theta Replication of Viral Genomes

ABSTRACTHuman papillomaviruses (HPVs) are important pathogens with a significant medical burden. HPV genomes replicate in infected cells via bidirectional theta replication and a poorly understood unidirectional mechanism. In this report, we provide evidence that the previously described interaction between the viral E1 helicase and the cellular UAF1-USP1 deubiquitinating enzyme complex, a member of the Fanconi anemia DNA damage response pathway, is required for the completion of the bidirectional theta replication of the HPV11 genome and the subsequent initiation of the unidirectional replication. We show that unidirectional replication proceeds via theta structures and is supported by the cellular Bloom helicase, which interacts directly with E1 and whose engagement in HPV11 replication requires UAF1-USP1 activity. We propose that the unidirectional replication of the HPV11 genome initiates from replication fork restart events. These findings suggest a new role for the Fanconi anemia pathway in HPV replication.IMPORTANCEHuman papillomaviruses (HPVs) are important pathogens that replicate their double-stranded circular DNA genome in the nucleus of infected cells. HPV genomes replicate in infected cells via bidirectional theta replication and a poorly understood unidirectional mechanism, and the onset of viral replication requires the engagement of cellular DNA damage response pathways. In this study, we showed that the previously described interaction between the viral E1 helicase and the cellular UAF1-USP1 complex is necessary for the completion of bidirectional replication and the subsequent initiation of the unidirectional replication mechanism. Our results suggest HPVs may use the cellular Fanconi anemia DNA damage pathway to achieve the separation of daughter molecules generated by bidirectional theta replication. Additionally, our results indicate that the unidirectional replication of the HPV genome is initiated from restarted bidirectional theta replication forks.

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Differential Requirements of the C Terminus of Nbs1 in Suppressing Adenovirus DNA Replication and Promoting Concatemer Formation

Journal of Virology ◽

10.1128/jvi.00900-08 ◽

2008 ◽

Vol 82 (17) ◽

pp. 8362-8372 ◽

Cited By ~ 40

Author(s):

Seema S. Lakdawala ◽

Rachel A. Schwartz ◽

Kevin Ferenchak ◽

Christian T. Carson ◽

Brian P. McSharry ◽

...

Keyword(s):

Dna Damage ◽

Dna Replication ◽

Viral Replication ◽

Dna Damage Response ◽

Viral Genomes ◽

Mrn Complex ◽

E4 Region ◽

C Terminus ◽

Damage Response ◽

Cellular Dna

ABSTRACT Adenoviruses (Ad) with the early region E4 deleted (E4-deleted virus) are defective for DNA replication and late protein synthesis. Infection with E4-deleted viruses results in activation of a DNA damage response, accumulation of cellular repair factors in foci at viral replication centers, and joining together of viral genomes into concatemers. The cellular DNA repair complex composed of Mre11, Rad50, and Nbs1 (MRN) is required for concatemer formation and full activation of damage signaling through the protein kinases Ataxia-telangiectasia mutated (ATM) and ATM-Rad3-related (ATR). The E4orf3 and E4orf6 proteins expressed from the E4 region of Ad type 5 (Ad5) inactivate the MRN complex by degradation and mislocalization, and prevent the DNA damage response. Here we investigated individual contributions of the MRN complex, concatemer formation, and damage signaling to viral DNA replication during infection with E4-deleted virus. Using virus mutants, short hairpin RNA knockdown and hypomorphic cell lines, we show that inactivation of MRN results in increased viral replication. We demonstrate that defective replication in the absence of E4 is not due to concatemer formation or DNA damage signaling. The C terminus of Nbs1 is required for the inhibition of Ad DNA replication and recruitment of MRN to viral replication centers. We identified regions of Nbs1 that are differentially required for concatemer formation and inhibition of Ad DNA replication. These results demonstrate that targeting of the MRN complex explains the redundant functions of E4orf3 and E4orf6 in promoting Ad DNA replication. Understanding how MRN impacts the adenoviral life cycle will provide insights into the functions of this DNA damage sensor.

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Adenovirus Core Protein VII Downregulates the DNA Damage Response on the Host Genome

Journal of Virology ◽

10.1128/jvi.01089-17 ◽

2017 ◽

Vol 91 (20) ◽

Cited By ~ 15

Author(s):

Daphne C. Avgousti ◽

Ashley N. Della Fera ◽

Clayton J. Otter ◽

Christin Herrmann ◽

Neha J. Pancholi ◽

...

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Core Protein ◽

Host Genome ◽

Human Pathogens ◽

Viral Genomes ◽

Successful Infection ◽

Damage Response ◽

Cellular Dna ◽

Host Chromatin

ABSTRACT Viral manipulation of cellular proteins allows viruses to suppress host defenses and generate infectious progeny. Due to the linear double-stranded DNA nature of the adenovirus genome, the cellular DNA damage response (DDR) is considered a barrier to successful infection. The adenovirus genome is packaged with protein VII, a virally encoded histone-like core protein that is suggested to protect incoming viral genomes from detection by the cellular DNA damage machinery. We showed that protein VII localizes to host chromatin during infection, leading us to hypothesize that protein VII may affect DNA damage responses on the cellular genome. Here we show that protein VII at cellular chromatin results in a significant decrease in accumulation of phosphorylated H2AX (γH2AX) following irradiation, indicating that protein VII inhibits DDR signaling. The oncoprotein SET was recently suggested to modulate the DDR by affecting access of repair proteins to chromatin. Since protein VII binds SET, we investigated a role for SET in DDR inhibition by protein VII. We show that knockdown of SET partially rescues the protein VII-induced decrease in γH2AX accumulation on the host genome, suggesting that SET is required for inhibition. Finally, we show that knockdown of SET also allows ATM to localize to incoming viral genomes bound by protein VII during infection with a mutant lacking early region E4. Together, our data suggest that the protein VII-SET interaction contributes to DDR evasion by adenovirus. Our results provide an additional example of a strategy used by adenovirus to abrogate the host DDR and show how viruses can modify cellular processes through manipulation of host chromatin. IMPORTANCE The DNA damage response (DDR) is a cellular network that is crucial for maintaining genome integrity. DNA viruses replicating in the nucleus challenge the resident genome and must overcome cellular responses, including the DDR. Adenoviruses are prevalent human pathogens that can cause a multitude of diseases, such as respiratory infections and conjunctivitis. Here we describe how a small adenovirus core protein that localizes to host chromatin during infection can globally downregulate the DDR. Our study focuses on key players in the damage signaling pathway and highlights how viral manipulation of chromatin may influence access of DDR proteins to the host genome.

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ATR and ATRIP Are Recruited to Herpes Simplex Virus Type 1 Replication Compartments Even though ATR Signaling Is Disabled

Journal of Virology ◽

10.1128/jvi.01643-10 ◽

2010 ◽

Vol 84 (23) ◽

pp. 12152-12164 ◽

Cited By ~ 41

Author(s):

Kareem N. Mohni ◽

Christine M. Livingston ◽

David Cortez ◽

Sandra K. Weller

Keyword(s):

Dna Damage ◽

Herpes Simplex ◽

Dna Damage Response ◽

Damage Response ◽

Infected Cells ◽

Cellular Dna ◽

Simplex Virus ◽

Atr Kinase ◽

Hsv 1

ABSTRACT Although the herpes simplex virus type 1 (HSV-1) genome might be expected to induce a DNA damage response, the ATR kinase is not activated in infected cells. We previously proposed that spatial uncoupling of ATR from its interaction partner, ATRIP, could be the basis for inactivation of the ATR kinase in infected cells; however, we now show that ATR and ATRIP are in fact both recruited to HSV-1 replication compartments and can be coimmunoprecipitated from infected-cell lysates. ATRIP and replication protein A (RPA) are recruited to the earliest detectable prereplicative sites, stage II microfoci. In a normal cellular DNA damage response, ATR/ATRIP are recruited to stretches of RPA-coated single-stranded DNA in an RPA- and kinase-dependent manner, resulting in the phosphorylation of RPA by ATR in damage foci. In contrast, in HSV-1-infected cells, RPA is not phosphorylated, and endogenous phosphorylated RPA is excluded from stage II microfoci; in addition, the recruitment of ATR/ATRIP is independent of RPA and the kinase activity of ATR. Furthermore, we show that ATR/ATRIP play a beneficial role in viral gene expression and virus production. Although ICP0 has been shown to be important for partial inactivation of other cellular DNA repair pathways, we show that ICP0 is not responsible for the inactivation of ATR signaling and, furthermore, that neither ATR nor ATRIP is a target of ICP0 degradation. Thus, ATR and ATRIP may function outside the context of the canonical ATR damage signaling pathway during HSV-1 infection to participate in the viral life cycle.

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Faculty Opinions recommendation of Activation of the cellular DNA damage response in the absence of DNA lesions.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1108695.571444 ◽

2008 ◽

Author(s):

Yosef Gruenbaum

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Dna Lesions ◽

Damage Response ◽

Cellular Dna

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Targeting Protein-Protein Interactions in the DNA Damage Response Pathways for Cancer Chemotherapy

RSC Chemical Biology ◽

10.1039/d1cb00101a ◽

2021 ◽

Author(s):

Kerry Silva McPherson ◽

Dmitry Korzhnev

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Protein Interactions ◽

Cell Cycle Progression ◽

Protein Protein Interactions ◽

Cycle Progression ◽

Damage Recognition ◽

Damage Response ◽

Cellular Dna ◽

Dna Damage Recognition

Cellular DNA damage response (DDR) is an extensive signaling network that orchestrates DNA damage recognition, repair and avoidance, cell cycle progression and cell death. DDR alternation is a hallmark of...

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Avian Sarcoma and Leukosis Virus Cytopathic Effect in the Absence of TVB Death Domain Signaling

Journal of Virology ◽

10.1128/jvi.79.13.8243-8248.2005 ◽

2005 ◽

Vol 79 (13) ◽

pp. 8243-8248 ◽

Cited By ~ 7

Author(s):

Sara Klucking ◽

Asha S. Collins ◽

John A. T. Young

Keyword(s):

Dna Damage ◽

Signaling Pathways ◽

Dna Damage Response ◽

Cytopathic Effect ◽

Tumor Necrosis Factor Receptor ◽

Death Domain ◽

Trail Receptors ◽

Damage Response ◽

Cellular Dna ◽

Avian Sarcoma

ABSTRACT The cytopathic effect (CPE) seen with some subgroups of avian sarcoma and leukosis virus (ASLV) is associated with viral Env activation of the death-promoting activity of TVB (a tumor necrosis factor receptor-related receptor that is most closely related to mammalian TNF-related apoptosis-inducing ligand [TRAIL] receptors) and with viral superinfection leading to unintegrated viral DNA (UVD) accumulation, which is presumed to activate a cellular DNA damage response. In this study, we employed cells that express signaling-deficient ASLV receptors to demonstrate that an ASLV CPE can be uncoupled from the death-promoting functions of the TVB receptor. However, these cell-killing events were associated with much higher levels of viral superinfection and DNA accumulation than those seen when the virus used signaling-competent TVB receptors. These findings suggest that a putative cellular DNA damage response that is activated by UVD accumulation might act in concert with the death-signaling pathways activated by Env-TVB interactions to trigger cell death. Such a model is consistent with the well-established synergy that exists between TRAIL-signaling pathways and DNA damage responses which is currently being exploited in cancer therapy regimens.

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