FIGURE 1.
JNK activation is required for the repair of nitric oxide-induced DNA damage. INS 832/13 cells were pretreated for 30 min with TAT-TI-JIP153–163 (A and B) or SP600125 (C) at the indicated concentrations. DEANO (1 mm) was added, and the cells were cultured for 1 h, or they were cultured for 1 h, washed to remove the nitric oxide donor, and cultured for 5 additional h (repair conditions). The cells were harvested, and DNA damage was determined using the comet assay (A). This damage was quantified as the mean tail moment on 30–50 cells/condition (B and C). JNK inhibitor activity was assessed by ATF-2 or c-Jun phosphorylation in INS 832/13 cells preincubated for 30 min with TAT-TI-JIP153–163 or SP600125, respectively, followed by a 30-min treatment with IL-1 (D). Results are representative of three independent experiments.