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Suicidal cross-linking of PARP-1 to AP site intermediates in cells undergoing base excision repair
- Source :
- Nucleic Acids Research
- Publication Year :
- 2014
- Publisher :
- Oxford University Press (OUP), 2014.
-
Abstract
- Poly(ADP-ribose) polymerase-1 (PARP-1) is an abundant nuclear enzyme in mammalian cells. The enzyme synthesizes polymers of ADP-ribose from the coenzyme NAD(+) and plays multifaceted roles in cellular responses to genotoxic stress, including DNA repair. It had been shown that mouse fibroblasts treated with a DNA methylating agent in combination with a PARP inhibitor exhibit higher cytotoxicity than cells treated with methylating agent alone. This lethality of the PARP inhibitor is dependent on apurinic/apyrimidinic (AP) sites in the DNA and the presence of PARP-1. Here, we show that purified PARP-1 is capable of forming a DNA-protein cross-link (DPC) by covalently attaching to the AP site. This DPC formation is specific to the presence of the natural AP site in DNA and is accompanied by a single-strand DNA incision. Cellular studies confirm the formation of PARP-1 DPCs during alkylating agent-induced base excision repair (BER) and formation of DPCs is enhanced by a PARP inhibitor. Using an N-terminal and C-terminal truncated PARP-1 we show that a polypeptide fragment comprising the zinc 3 and BRCT sub-domains is sufficient for DPC formation. The covalent attachment of PARP-1 to AP site-containing DNA appears to be a suicidal event when BER is overwhelmed or disrupted.
- Subjects :
- DNA Repair
DNA repair
Poly ADP ribose polymerase
Poly (ADP-Ribose) Polymerase-1
Genome Integrity, Repair and Replication
Biology
AP endonuclease
Mice
03 medical and health sciences
Genetics
Animals
Humans
AP site
Cysteine
Cells, Cultured
030304 developmental biology
0303 health sciences
030302 biochemistry & molecular biology
DNA
Base excision repair
Molecular biology
Protein Structure, Tertiary
DNA glycosylase
PARP inhibitor
biology.protein
Poly(ADP-ribose) Polymerases
Nucleotide excision repair
Subjects
Details
- ISSN :
- 13624962 and 03051048
- Volume :
- 42
- Database :
- OpenAIRE
- Journal :
- Nucleic Acids Research
- Accession number :
- edsair.doi.dedup.....358a93db633b52abb92e2d5a6d7a525f