Peroxynitrite nitration of Tyr 56 in Hsp90 induces PC12 cell death through P2X7R-dependent PTEN activation.

The diffusion-limited reaction of nitric oxide (NO) and superoxide (O) produces peroxynitrite (ONOO), a biological oxidant that has been implicated in a number of pathological conditions, including neurodegenerative disorders. We previously reported that incubation of PC12 cells with peroxynitrite triggers apoptosis by simultaneously inhibiting the PI3K/Akt survival pathway, and activating the p38 and JNK MAP kinase pathways. We also reported that peroxynitrite-treated Heat Shock Protein 90 (Hsp90) stimulates PC12 cell death.