UV-mediated activation of JNK and expression of Egr-1 in FA-A primary leukocytes. (A) Peripheral blood mononuclear cells from a healthy donor (Con) and a patient with FA-A were exposed to UV radiation, and then cell lysates were immunoprecipitated with anti-JNK and subjected to immune complex kinase assay with GST-ATF2 as substrate (top panel). The lysates were analyzed by Western blot with anti-JNK (bottom panel). (B) Total RNA from UV-treated cells was extracted and analyzed for the expression of Egr-1 mRNA by semiquantitative RT-PCR. The levels of p21 were also analyzed. GAPDH mRNA was used as an amplification control.