Adeno-associated virus replication induces a DNA damage response coordinated by DNA-dependent protein kinase

J Virol. 2009 Jun;83(12):6269-78. doi: 10.1128/JVI.00318-09. Epub 2009 Apr 1.

Abstract

The parvovirus adeno-associated virus (AAV) contains a small single-stranded DNA genome with inverted terminal repeats that form hairpin structures. In order to propagate, AAV relies on the cellular replication machinery together with functions supplied by coinfecting helper viruses such as adenovirus (Ad). Here, we examined the host cell response to AAV replication in the context of Ad or Ad helper proteins. We show that AAV and Ad coinfection activates a DNA damage response (DDR) that is distinct from that seen during Ad or AAV infection alone. The DDR was also triggered when AAV replicated in the presence of minimal Ad helper proteins. We detected autophosphorylation of the kinases ataxia telangiectasia mutated (ATM) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and signaling to downstream targets SMC1, Chk1, Chk2, H2AX, and XRCC4 and multiple sites on RPA32. The Mre11 complex was not required for activation of the DDR to AAV infection. Additionally, we found that DNA-PKcs was the primary mediator of damage signaling in response to AAV replication. Immunofluorescence revealed that some activated damage proteins were found in a pan-nuclear pattern (phosphorylated ATM, SMC1, and H2AX), while others such as DNA-PK components (DNA-PKcs, Ku70, and Ku86) and RPA32 accumulated at AAV replication centers. Although expression of the large viral Rep proteins contributed to some damage signaling, we observed that the full response required replication of the AAV genome. Our results demonstrate that AAV replication in the presence of Ad helper functions elicits a unique damage response controlled by DNA-PK.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Adenoviridae / physiology
  • Ataxia Telangiectasia Mutated Proteins
  • Cell Cycle Proteins / metabolism
  • DNA Damage*
  • DNA, Viral / genetics
  • DNA-Activated Protein Kinase / metabolism*
  • DNA-Binding Proteins / metabolism
  • Dependovirus / genetics
  • Dependovirus / physiology*
  • HeLa Cells
  • Humans
  • Parvoviridae Infections / virology
  • Phosphorylation
  • Protein Serine-Threonine Kinases / metabolism
  • Signal Transduction*
  • Tumor Suppressor Proteins / metabolism
  • Virus Replication*

Substances

  • Cell Cycle Proteins
  • DNA, Viral
  • DNA-Binding Proteins
  • Tumor Suppressor Proteins
  • ATM protein, human
  • Ataxia Telangiectasia Mutated Proteins
  • DNA-Activated Protein Kinase
  • Protein Serine-Threonine Kinases