Fig. 2.

Impact of experimental parameters on the activity of regulatory nodes for cell cycle control. a Impact of combinatorial expression of key regulatory nodes on cell cycle arrest in G0/1. U2-OS cells were transiently co-transfected with plasmids encoding overexpression of combinations of one, two, and three key node proteins. The resulting arrest in G0/1 of the cell population was assayed via DNA staining and flow cytometry. b Impact of p16 on cell cycle arrest in G0/1 of different cell lines. HeLa, HEK293, or U2-OS cells were transiently transfected with a plasmid encoding p16 or a control and the percentage of the cell population in G0/1 was measured. c Impact of the arrangement of expression cassettes encoding regulatory nodes on cell cycle arrest in G0/1. U2-OS cells were transiently transfected with a single plasmid containing two expression cassettes, encoding a transfection marker and a regulatory node (p16 or p27) in tandem, or with two plasmids separately encoding the transfection marker and the regulatory node. The resulting arrest in G0/1 of the cell population was assayed. *, p < 0.05. Error bars represent standard deviation across biological triplicates