A CRISPR-based rapid DNA repositioning strategy and the early intranuclear life of HSV-1
Abstract
The relative positions of viral DNA genomes to the host intranuclear environment play critical roles in determining virus fate. Recent advances in the application of chromosome conformation capture-based sequencing analysis (3C technologies) have revealed valuable aspects of the spatiotemporal interplay of viral genomes with host chromosomes. However, to elucidate the causal relationship between the subnuclear localization of viral genomes and the pathogenic outcome of an infection, manipulative tools are needed. Rapid repositioning of viral DNAs to specific subnuclear compartments amid infection is a powerful approach to synchronize and interrogate this dynamically changing process in space and time. Herein, we report an inducible CRISPR-based two-component platform that relocates extrachromosomal DNA pieces (5 kb to 170 kb) to the nuclear periphery in minutes (CRISPR-nuPin). Based on this strategy, investigations of herpes simplex virus 1 (HSV-1), a prototypical member of the human herpesvirus family, revealed unprecedently reported insights into the early intranuclear life of the pathogen: I) Viral genomes tethered to the nuclear periphery upon entry, compared with those freely infecting the nucleus, were wrapped around histones with increased suppressive modifications and subjected to stronger transcriptional silencing and prominent growth inhibition. II) Relocating HSV-1 genomes at 1 hour post infection significantly promoted the transcription of viral genes, termed an 'Escaping' effect. III) Early accumulation of ICP0 was a sufficient but not necessary condition for 'Escaping'. IV) Subnuclear localization was only critical during early infection. Importantly, the CRISPR-nuPin tactic, in principle, is applicable to many other DNA viruses.
Data availability
No datasets and code were generated or used during the study. All raw microscopy images, original files for charts and blots on Dryad.
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A CRISPR-based rapid DNA repositioning strategy and the early intranuclear life of HSV-1Dryad Digital Repository, doi:10.5061/dryad.vmcvdncxd.
Article and author information
Author details
Funding
National Key Research and Development Program of China (2022YFC2305400)
- Pei Xu
National Natural Science Foundation of China (No. 31870157)
- Pei Xu
Shenzhen Science and Technology Innovation Program (JCYJ20180307151536743)
- Pei Xu
Shenzhen Science and Technology Innovation Program (KQTD20180411143323605)
- Pei Xu
Natural Science Foundation of Shenzhen Municipality (JCYJ2022050145810023)
- Pei Xu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Xiang 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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