Peg3/Pw1 is a mediator between p53 and Bax in DNA damage-induced neuronal death.

Neuronal cell death after DNA damage requires p53 and Bax, but the mechanism by which p53 activation leads to Bax translocation and cell death in neurons is not known. We report here that Peg3/Pw1 is up-regulated after DNA damage in cortical neurons in a p53-dependent manner. Overexpression of Peg3/Pw1 leads to decreased neuronal viability. The deleterious effect of Peg3/Pw1 on neuronal survival is abrogated by deletion of either p53 or Bax, indicating an essential role for both in Peg3/Pw1-mediated neuronal death. Moreover, overexpression of a Peg3/Pw1 dominant negative protein inhibits Bax translocation and neuronal cell death after DNA damage. These findings implicate Peg3/Pw1 as a mediator between p53 and Bax in a neuronal cell death pathway activated by DNA damage.