(A) BrdU incorporation was assessed as described in Experimental Procedures in asynchronous CHO-K1 cells expressing either the wild-type GFP WT-CLS, GFP-Myc (control) or the GFP CLS SWNQ-A mutant. Error bars represent mean±SD (n=3).
(B) BrdU incorporation was assessed in CHO-K1 cells synchronized by double thymidine treatment. Cells were transfected with the indicated CLS constructs during the second thymidine treatment, released from the G1-S boundary by thymidine washout, and harvested at the indicated times as described in Experimental Procedures. Error bars represent mean ± SD (n=3).
(C) Phosphorylation of p38 MAPK at activating sites was analyzed by western blotting (Upper) in CHO-K1 cells synchronized by double thymidine treatment and transfected with the indicated CLS constructs as in Panel B, or treated with 500 mM sorbitol for 30 mm. Total p38 served as a loading control (Lower).