Automodification switches PARP-1 function from chromatin architectural protein to histone chaperone
Abstract
Poly-ADP-ribosylation (PARylation) is an abundant posttranslational modification in eukaryotes. The responsible enzyme, poly [ADP-ribose] polymerase 1 (PARP-1), binds to chromatin and shapes its architecture. It is activated by DNA damage and other triggers, and catalyzes the addition of long chains of poly-ADP ribose (PAR) mainly to itself. The biological effects of PARylation are unknown. Here, we show that PARylation confers the ability to bind histones and to assemble nucleosomes upon PARP-1, and also affects its interaction with chromatin. The rapid turnover of PAR groups provides a mechanism for switching PARP-1 function from nucleosome binder to nucleosome assembler. This explains the involvement of active PARP-1 in both transcription and DNA damage repair, because histone chaperone activity is required during both processes.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- September 2014
- DOI:
- Bibcode:
- 2014PNAS..11112752M