Figure 5.

Knocking down PPM1G renders cells resistant to G1 cell cycle arrest. A. PPM1G knockdown decreases p27 protein level at G1 phase. The p27 level in HeLa cells stably expressing PPM1G shRNA or carrying control was examined as described in Figure 4A. B. PPM1G depletion increases cell proliferation. HeLa cells were cultured under serum derprivation condition. Cell number was determined every 24 h with a hemocytometer. C. PPM1G depletion promotes DNA synthesis. DNA synthesis in HeLa cells was measured by using BrdU incorporation assay.