Viruses have proven to be powerful tools to study fundamental cellular mechanisms. In this proposal we will focus on interactions of viruses with cellular DNA repair pathways. We have discovered that viral genomes can represent substrates for the cellular DNA repair machinery, and that viral infection can lead to activation of signaling pathways characteristic of the DNA damage response. We will use the human adeno-associated virus (AAV) as a simple model system to study interactions with cellular factors. AAV possesses a single-stranded DNA genome and a biphasic lifecycle that requires helper viruses for efficient productive infection. We have uncovered a novel cellular DNA damage response that is activated by AAV co-infection with adenovirus, involving signaling by PI3-like kinases through cellular repair proteins. We will investigate the nature of the damage response, the viral elements that trigger it, the cellular kinases involved, and its impact on virus replication. The virus lifecycle is subject to remarkable spatial and temporal regulation, with the formation of structures within the nucleus where viral replication occurs. We will develop live cell imaging approaches to visualize AAV infection and will use these to (1) detect the conversion of incoming single- stranded DNA genomes to a duplex form, (2) study the dynamics of viral replication and (3) track interactions of cellular repair factors with viral replication centers. Our studies have demonstrated that viruses provide model systems to study the cellular responses to DNA damage. The experiments proposed in this grant will address mechanistic aspects of the recognition of the AAV genome by cellular repair proteins and how this cellular response affects virus infection. We will use a combination of genetic, biochemical and cytological approaches to study these host responses to viral infection. Recombinant forms of AAV provide one of the simplest and most promising vectors for gene therapy applications. Understanding how the cell recognizes, responds and processes viral DNA, is important for any gene therapy approach that delivers genetic material in viral vectors. Therefore, in addition to providing insights into the fundamental process of recognition of damaged DNA, these studies will also have implications for genetic approaches to combat disease. ? ?

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
Project #
Application #
Study Section
Virology - A Study Section (VIRA)
Program Officer
Park, Eun-Chung
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Salk Institute for Biological Studies
La Jolla
United States
Zip Code
Weitzman, Matthew D; Weitzman, Jonathan B (2014) What's the damage? The impact of pathogens on pathways that maintain host genome integrity. Cell Host Microbe 15:283-94
Chaurushiya, Mira S; Lilley, Caroline E; Aslanian, Aaron et al. (2012) Viral E3 ubiquitin ligase-mediated degradation of a cellular E3: viral mimicry of a cellular phosphorylation mark targets the RNF8 FHA domain. Mol Cell 46:79-90
Narvaiza, Inigo; Landry, Sebastien; Weitzman, Matthew D (2012) APOBEC3 proteins and genomic stability: the high cost of a good defense. Cell Cycle 11:33-8
Landry, Sebastien; Narvaiza, Inigo; Linfesty, Daniel C et al. (2011) APOBEC3A can activate the DNA damage response and cause cell-cycle arrest. EMBO Rep 12:444-50
Weitzman, Matthew D; Lilley, Caroline E; Chaurushiya, Mira S (2011) Changing the ubiquitin landscape during viral manipulation of the DNA damage response. FEBS Lett 585:2897-906
Weitzman, Matthew D; Linden, R Michael (2011) Adeno-associated virus biology. Methods Mol Biol 807:1-23
Lilley, Caroline E; Chaurushiya, Mira S; Weitzman, Matthew D (2010) Chromatin at the intersection of viral infection and DNA damage. Biochim Biophys Acta 1799:319-27
Lamarche, Brandon J; Orazio, Nicole I; Weitzman, Matthew D (2010) The MRN complex in double-strand break repair and telomere maintenance. FEBS Lett 584:3682-95
Weitzman, Matthew D; Lilley, Caroline E; Chaurushiya, Mira S (2010) Genomes in conflict: maintaining genome integrity during virus infection. Annu Rev Microbiol 64:61-81
Chaurushiya, Mira S; Weitzman, Matthew D (2009) Viral manipulation of DNA repair and cell cycle checkpoints. DNA Repair (Amst) 8:1166-76

Showing the most recent 10 out of 11 publications