FIG. 4.

The MRN complex is not required for the ATM response to hypoxia. LCLs of the genotypes shown were used for these experiments. (A) Cells were treated with NCS (5 ng/ml) for 10 min before harvesting. (B) A longer time course was then carried out with NCS (5 ng/ml). (C and D) Cells were then exposed to 0.02% O₂ for the times indicated, and Western blotting was carried out for the proteins/modifications shown. (E) RKO cells were exposed to hypoxia for the times indicated in the presence/absence of PARP inhibitor (PARPi), 4-amino-1,8-naphthalimide (10 μM). Western blotting was carried out for the proteins indicated. WT, wild type.