Herpesviral lytic gene functions render the viral genome susceptible to novel editing by CRISPR/Cas9
Abstract
Herpes simplex virus (HSV) establishes lifelong latent infection and can cause serious human disease, but current antiviral therapies target lytic but not latent infection. We screened for sgRNAs that cleave HSV-1 DNA sequences efficiently in vitro and used these sgRNAs to observe the first editing of quiescent HSV-1 DNA. The sgRNAs targeted lytic replicating viral DNA genomes more efficiently than quiescent genomes, consistent with the open structure of lytic chromatin. Editing of latent genomes caused short indels while editing of replicating genomes produced indels, linear molecules and large genomic sequence loss around the gRNA target site. The HSV ICP0 protein and viral DNA replication increased the loss of DNA sequences around the gRNA target site. We conclude that HSV, by promoting open chromatin needed for viral gene expression and by inhibiting the DNA damage response, makes the genome vulnerable to a novel form of editing by CRISPR-Cas9 during lytic replication.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Human herpesvirus 1 isolate KOS, complete genomeNCBI GenBank: KT899744.1.
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hg38Genome Reference Consortium, Human GRCh38.p12 (GCA_000001405.27).
Article and author information
Author details
Funding
National Institutes of Health (P01 AI098681)
- David M Knipe
National Institutes of Health (R21 AI135423)
- Kevin C Eggan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Oh et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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