Résumé
Promyelocytic leukemia nuclear bodies (PML NBs) are nuclear subdomains that respond to genotoxic stress by increasing in number via changes in chromatin structure. However, the role of the PML protein and PML NBs in specific mechanisms of DNA repair has not been fully characterized. Here, we have directly examined the role of PML in homologous recombination (HR) using I-SceI extrachromosomal and chromosome-based homology-directed repair (HDR) assays, and in HDR by CRISPR/Cas9-mediated gene editing. We determined that PML loss can inhibit HR in an extrachromosomal HDR assay but had less of an effect on CRISPR/Cas9-mediated chromosomal HDR. Overexpression of PML also inhibited both CRISPR HDR and I-SceI-induced HDR using a chromosomal reporter, and in an isoform-specific manner. However, the impact of PML overexpression on the chromosomal HDR reporter was dependent on the intranuclear chromosomal positioning of the reporter. Specifically, HDR at the TAP1 gene locus, which is associated with PML NBs, was reduced compared with a locus not associated with a PML NB; yet, HDR could be reduced at the non-PML NB-associated locus by PML overexpression. Thus, both loss and overexpression of PML isoforms can inhibit HDR, and proximity of a chromosomal break to a PML NB can impact HDR efficiency.
Langue d'origine | English |
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Pages (de-à) | 314-326 |
Nombre de pages | 13 |
Journal | Biochemistry and Cell Biology |
Volume | 98 |
Numéro de publication | 3 |
DOI | |
Statut de publication | Published - 2020 |
Note bibliographique
Funding Information:This work was supported by a Discovery Grant from the Natural Science and Engineering Research Council of Canada (NSERC) to G.D. (RGPIN 05616); G.D. is a Senior Scientist of the Beatrice Hunter Cancer Research Institute (BHCRI). K.M.A. was supported by a Killam Trust Predoctoral Scholarship, and studentships from NSERC and the BHCRI, with funds provided by The Terry Fox Foundation. D.C. was supported by a Nova Scotia Graduate Scholarship, and S.M. is supported by a Canada Graduate Scholarship (NSERC), a Killam Trust Predoctoral Scholarship, and the Scotia Scholars Award from the Nova Scotia Health Research Foundation (NSHRF).
Publisher Copyright:
© 2020, Canadian Science Publishing. All rights reserved.
ASJC Scopus Subject Areas
- Biochemistry
- Molecular Biology
- Cell Biology
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't