Figure 5. Control of timing in cell-cycle progression but not commitment decision by G1 Cyclin/CDK complexes.
(a) Scatter plot based on commitment as determined by Amp under inhibition of CDKs (PD0332991 for CDK4/6 and CVT-313 for CDK2). Committed cells were measured by EdU labelling after 48 h incubation, and divided cells were counted 48 h after addition of 10% BGS. (b) Histogram based on cell division as determined by Amp under inhibition of CDKs (48 h observation). (c) Proportion of committed/divided cells under different inhibitions of CDKs during a 48- and 92-h (the latter only for the combined inhibition) observation window. The exact number of total cells followed and that of cells committed/divided are indicated on top of each error bar. (d) Four representative E2F1 dynamics trajectories under the same conditions as a. Each colour bar on top indicates the length of t2 of its corresponding trajectory. (e) Distribution of t2 of individual cells in mock, CDK4/6-, CDK2- and combinational inhibited samples. Mean±s.d. is shown on top right of each panel. 54 (Vehicle), 106 (15 nM PD0332991), 102 (100 nM PD0332991), 109 (1 μM PD0332991), 94 (1 μM CVT313), 105 (5 μM CVT313) and 101 (1 μM PD0332991 and 5 μM CVT313) cells were analysed for each condition, respectively. (f) Plot of the first cell cycle length (T) under the condition as in e. Every dot represents a single cell. Black cross indicates the median of T among the cells divided within 48 h. *P=0.01855, Wilcoxon one-side test. For all testing results, P<0.005 unless marked.