FIG. 9.

Ectopic expression of HIRA causes arrest in S phase of the cell cycle. (a) U2OS cells were transfected without (−HIRA) or with (+HIRA) a plasmid encoding WT HA-HIRA[1–1017] together with a plasmid encoding cell surface marker pCD19. Two days after transfection the cells were processed for two-color FACS analysis to determine the DNA content (propidium iodide staining) of the transfected cells (CD19 positive). The dot plots show DNA content of transfected and untransfected cells. Transfected cells (CD19 positive) are boxed (R1). The histograms show DNA content of only the transfected cells. FITC, fluorescein isothiocyanate. (b) U2OS cells were transfected without (−HIRA) or with (+HIRA) a plasmid encoding WT HA-HIRA[1–1017] together with a plasmid encoding cell surface marker pCD19. Two days after transfection the cells were pulse-labeled for 1 h with 5′-BrdU and then processed for two-color FACS analysis to determine whether the transfected cells were actively synthesizing DNA (5′-BrdU-positive cells). The dot plots show 5′-BrdU labeling of transfected and untransfected cells. Transfected cells (CD19 positive) are boxed (R1). The histograms show 5′-BrdU labeling of only the transfected cells.