Figure 5.

Knockdown of Δ133p53 arrests cell growth at the G2 phase and promotes cell senescence upon γ-irradiation. (A) Cell colony formation of irradiated cells. QSG-7701 cells transfected with non-specific siNS, Δ133p53i-1, or Δ133p53i-2 siRNA were treated with 10 gray of γ-ray irradiation. The pictures were taken at 5 dpi. (B) FACS analysis of the percentage of cells at different cell cycle phases based on Propidium Iodide (PI) staining. QSG-7701 cells transfected with siNS, Δ133p53i-1, or Δ133p53i-2 siRNA at 5 dpi as indicated. (C) SA-β-gal staining to analyze the senescence status in the QSG-7701 cells with different treatments as described in B. (D) Statistical analysis of the senescent cells in different samples shown in C.