title: HPV31 utilizes the ATR-Chk1 pathway to maintain elevated RRM2 levels and a replication-competent environment in differentiating Keratinocytes.
abstract: Productive replication of human papillomaviruses (HPV) is restricted to the uppermost layers of the differentiating epithelia. How HPV ensures an adequate supply of cellular substrates for viral DNA synthesis in a differentiating environment is unclear. Here, we demonstrate that HPV31 positive cells exhibit increased dNTP pools and levels of RRM2, a component of the ribonucleotide reductase (RNR) complex, which is required for de novo synthesis of dNTPs. RRM2 depletion blocks productive replication, suggesting RRM2 provides dNTPs for viral DNA synthesis in differentiating cells. We demonstrate that HPV31 regulates RRM2 levels through expression of E7 and activation of the ATR-Chk1-E2F1 DNA damage response, which is essential to combat replication stress upon entry into S-phase, as well as for productive replication. Our findings suggest a novel way in which viral DNA synthesis is regulated through activation of ATR and Chk1 and highlight an intriguing new virus/host interaction utilized for viral replication.
authors.affiliation: Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, North Carolina, USA.
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Anacker
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, North Carolina, USA.
authors.forename: Heather L
authors.initials: HL
authors.lastname: Aloor
authors.affiliation: The Center for Drug Discovery, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
authors.forename: Caitlin N
authors.initials: CN
authors.lastname: Shepard
authors.affiliation: The Center for Drug Discovery, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
authors.forename: Gina M
authors.initials: GM
authors.lastname: Lenzi
authors.affiliation: Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, North Carolina, USA.
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Johnson
authors.affiliation: The Center for Drug Discovery, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA; Children's Healthcare of Atlanta, USA.
authors.forename: Baek
authors.initials: B
authors.lastname: Kim
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, North Carolina, USA; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, North Carolina, USA. Electronic address: camoody@med.unc.edu.
authors.forename: Cary A
authors.initials: CA
authors.lastname: Moody
mesh_terms: D064007:Ataxia Telangiectasia Mutated Proteins / Q000235:genetics / Q000378:metabolism; D000071877:Checkpoint Kinase 1 / Q000235:genetics / Q000378:metabolism*; D004249:DNA Damage; D004261:DNA Replication; D003853:Deoxyribonucleosides / Q000378:metabolism; D054884:Host-Pathogen Interactions; D058952:Human papillomavirus 31 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D015603:Keratinocytes / Q000201:enzymology / Q000821:virology*; D050725:Papillomavirus E7 Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D030361:Papillomavirus Infections / Q000201:enzymology* / Q000235:genetics / Q000821:virology; D000072417:Protein Domains; D012262:Ribonucleoside Diphosphate Reductase / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D003853:Deoxyribonucleosides; D050725:Papillomavirus E7 Proteins; C093713:ribonucleotide reductase M2; D012262:Ribonucleoside Diphosphate Reductase; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; C000605867:CHEK1 protein, human; D000071877:Checkpoint Kinase 1
keywords: DNA damage response; Human papillomavirus; Pathogenesis; Replication