FIG. 5.

pX-mediated p38 MAPK activation initiates G₂/M checkpoint in 4pX-1 cells. Flow cytometry analyses of 4pX-1 cells grown for 18 h ± tetracycline addition. Cells were treated with 5 μg of tetracycline/ml (A), not treated with tetracycline (B), or not treated with tetracycline while being treated with 10 μM SB 203580 (C). (D) Western blot analyses of 4pX-1 WCE isolated ± pX for 18 h and ± 10 μM SB 203580. Where indicated, Ser216 phosphorylation of Cdc25C (upper panel) or total Cdc25C (lower panel) was monitored. Quantitation was by the OPTIMAS 6.1 software.