The plant-specific RNA Polymerase V (Pol V) plays a key role in gene silencing, but its role in repair of double stranded DNA breaks is unclear. Excision of the transposable element mPing creates double stranded breaks that are repaired by NHEJ. We measured mPing excision site repair in multiple DNA methylation mutants including pol V using an mPing:GFP reporter. Two independent mutant alleles of pol V showed less GFP expression, indicating that the Pol V protein plays a role in excision site repair. Sequence analysis of the pol V excision sites indicated an elevated rate of large deletions consistent with less efficient repair. These results clarify the role of Pol V, but not other RNA-directed DNA methylation proteins (Pol IV) or maintenance DNA methylation pathways (MET1), in the repair of double-strand DNA breaks.
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This content will become publicly available on May 16, 2024
Pol V produced RNA facilitates transposable element excision site repair in Arabidopsis
The plant-specific RNA Polymerase V (Pol V) plays a key role in gene silencing, but its role in repair of double stranded DNA breaks is unclear. Excision of the transposable element mPing creates double stranded breaks that are repaired by NHEJ. We measured mPing excision site repair in multiple DNA methylation mutants including pol V using an mPing : GFP reporter. Two independent mutant alleles of pol V showed less GFP expression, indicating that the Pol V protein plays a role in excision site repair. Sequence analysis of the pol V excision sites indicated an elevated rate of large deletions consistent with less efficient repair. These results clarify the role of Pol V, but not other RNA-directed DNA methylation proteins (Pol IV) or maintenance DNA methylation pathways ( MET1 ), in the repair of double-strand DNA breaks.
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« less
- Award ID(s):
- 2149964
- NSF-PAR ID:
- 10488067
- Publisher / Repository:
- Caltech Library
- Date Published:
- Journal Name:
- microPublication biology
- ISSN:
- 2578-9430
- Page Range / eLocation ID:
- 000793
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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