Role of poly(ADP-ribose) formation in DNA repair.
Nature
confidence
Key findings
Review of poly(ADP-ribose) polymerase mechanism in DNA repair; no clinical or biological endpoints reported.
View source on PubMed (PMID 1549180) ↗
- Sample size
- Not reported
- Population
- Human cell-free DNA repair system (in vitro)
- Dosing
- Not reported
- Duration
- Not reported
- Route
- Not reported
- Blinding
- not_reported
- Controls
- none
- Drug class
- coenzyme
Full abstract
The abundant nuclear enzyme poly(ADP-ribose) polymerase catalyses the synthesis of poly(ADP-ribose) from nicotinamide adenine dinucleotide (NAD+). This protein has an N-terminal DNA-binding domain containing two zinc-fingers, which is linked to the C-terminal NAD(+)-binding domain by a short region containing several glutamic acid residues that are sites of auto-poly(ADP-ribosyl)ation. The intracellular production of poly(ADP-ribose) is induced by agents that generate strand interruptions in DNA. The branched homopolymer chains may attain a size of 200-300 residues but are rapidly degraded after synthesis. The function of poly(ADP-ribose) synthesis is not clear, although it seems to be required for DNA repair. Here we describe a human cell-free system that enables the role of poly(ADP-ribose) synthesis in DNA repair to be characterized. The results indicate that unmodified polymerase molecules bind tightly to DNA strand breaks; auto-poly(ADP-ribosyl)ation of the protein then effects its release and allows access to lesions for DNA repair enzymes.