Beta human papillomavirus 8E6 promotes alternative end-joining
- Fred Hutchinson Cancer Research Center, United States
- Kansas State University, United States
- University of Florida, United States
- Stony Brook University, United States
Abstract
Double strand breaks (DSBs) are one of the most lethal DNA lesions in cells. The E6 protein of beta-human papillomavirus (HPV8 E6) impairs two critical DSB repair pathways; homologous recombination (HR) and non-homologous end-joining (NHEJ). However, HPV8 E6 only delays DSB repair. How DSBs are repaired in cells with HPV8 E6 remains to be studied. We hypothesize that HPV8 E6 promotes a less commonly used DSB repair pathway, alternative end-joining (Alt-EJ). Using CAS9 based Alt-EJ reporters, we show that HPV8 E6 promotes Alt-EJ. Further, using small molecule inhibitors, CRISPR/CAS9 gene knockout, and HPV8 E6 mutant, we find that HPV8 E6 promotes Alt-EJ by binding p300, an acetyltransferase that facilitates DSB repair by HR and NHEJ. At least some of this repair occurs through a subset of Alt-EJ known as polymerase theta dependent end joining. Finally, whole genome sequencing analysis showed HPV8 E6 caused an increased frequency of deletions bearing the microhomology signatures of Alt-EJ. This study fills the knowledge gap of how DSB is repaired in cells with HPV8 E6 and the mutagenic consequences of HPV8 E6 mediated p300 destabilization. Broadly, this study supports the hypothesis that beta-HPV promotes cancer formation by increasing genomic instability.
Data availability
Sequences have been deposited in the NCBI SRA database with accession number (PRJNA 856469).
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Beta human papillomavirus 8E6 promotes alternative end-joiningNCBI BioProject, PRJNA856469.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (P20GM130448)
- Nicholas Wallace
NIH Research Enhancement Award (NCI R15 CA242057 01A1)
- Nicholas Wallace
U.S. Department of Defense (CMDRP PRCRP CA160224 (NW))
- Nicholas Wallace
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Hu 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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Beta human papillomavirus 8E6 promotes alternative end-joining
eLife 12:e81923.
https://doi.org/10.7554/eLife.81923
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