Poly(ADP-ribose) (PAR) polymer is a signal

Shaida A. Andrabi, Soo Kim No, Seong Woon Yu, Hongmin Wang, David W. Koh, Masayuki Sasaki, Judith A. Klaus, Takashi Otsuka, Zhizheng Zhang, Raymond C. Koehler, Patricia D. Hurn, Guy G. Poirier, Valina L. Dawson, Ted M. Dawson

Research output: Contribution to journalArticlepeer-review

460 Scopus citations


Excessive activation of the nuclear enzyme, poly(ADP-ribose) polymerase-1 (PARP-1) plays a prominent role in various of models of cellular injury. Here, we identify poly(ADP-ribose) (PAR) polymer, a product of PARP-1 activity, as a previously uncharacterized cell death signal. PAR polymer is directly toxic to neurons, and degradation of PAR polymer by poly(ADP-ribose) glycohydrolase (PARG) or phosphodiesterase 1 prevents PAR polymer-induced cell death. PARP-1-dependent, NMDA excitotoxicity of cortical neurons is reduced by neutralizing antibodies to PAR and by overexpression of PARG. Neuronal cultures with reduced levels of PARG are more sensitive to NMDA excitotoxicity than WT cultures. Transgenic mice overexpressing PARG have significantly reduced infarct volumes after focal ischemia. Conversely, mice with reduced levels of PARG have significantly increased infarct volumes after focal ischemia compared with WT littermate controls. These results reveal PAR polymer as a signaling molecule that induces cell death and suggests that interference with PAR polymer signaling may offer innovative therapeutic approaches for the treatment of cellular injury.

Original languageEnglish (US)
Pages (from-to)18308-18313
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number48
StatePublished - Nov 28 2006


  • Excitotoxicity
  • Poly(ADP-ribose) glycohydrolase
  • Poly(ADP-ribose) polymerase
  • Stroke

ASJC Scopus subject areas

  • General


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