Fig. 1.

DJ-1 protects against cell death induced by oxidative, but not nonoxidative, stress. Survival determinations for each of the following experiments are described in Experimental Procedures. (A) Increased sensitivity to H₂O₂ in the absence of DJ-1. Cortical neurons from DJ-1+/+, DJ-1+/–, and DJ-1–/–embryos were treated for 3 h with 30 μM H₂O₂. (B) Immunofluorescence analysis of DJ-1+/+ embryonic cortical neurons infected with an adenoviral vector (Ad) expressing either GFP or GFP plus DJ-1. Hoechst nuclear staining of the same culture is also shown. (C) Protective effect of DJ-1 overexpression in DJ-1+/+ cortical neurons. DJ-1+/+ neurons infected with adenovirus expressing GFP plus WT DJ-1 protein, but not GFP plus mutated (L166P) DJ-1 protein, showed increased survival after H₂O₂ exposure. Control, no H₂O₂. (D) Protective effect of WT DJ-1 in DJ-1–/–cortical neurons. DJ-1–/–neurons infected with adenovirus expressing GFP plus WT DJ-1 showed increased survival after H₂O₂ exposure. (E) Increased sensitivity of DJ-1–/–mesencephalic dopaminergic neurons (TH⁺) to other oxidative insults. DJ-1–/–cortical neurons were exposed to 10 nM rotenone for 24 h. (F and G) Lack of sensitivity of DJ-1–/–cortical neurons (TH⁺) to nonoxidative insults. The indicated doses of camptothecin (Fig. 1F) or 2 μM staurosporine (Fig. 1G) were applied to DJ-1+/+, DJ-1+/–, and DJ-1–/–neurons for 16 h. For A and C–G, each data point is the mean ± SEM of three to five independent cultures, where * denotes a significance level of P < 0.05.