Figure 3.

Targeting RSK inhibits radiation-induced YB-1 phosphorylation in nuclear fractions without affecting YB-1 nuclear level. SKBR3 and HBL-100 cells were treated with or without the RSK inhibitor LJI308 (both 5 µM, 2 h). At the indicated time-points after IR, cytoplasmic and nuclear protein fractions were prepared, and P-YB-1, YB-1, and RSK1/2/3 were detected by Western blotting. α-Tubulin and Lamin A/C were detected as cytoplasmic and nuclear markers, respectively. Arrows indicate distinct RSK isoforms.