Fig. 2

Diversity of cell cycle lengths in mammary epithelial cells. a Representative time-lapse images of the cell cycle determined by tracking Fucci2 fluorescence over 24 h from a cycling cell (upper panels) and a non-cycling cell residing in G1 (lower panels). b Histogram showing the distribution of G1 length (n = 250–300 segments) and S/G2/M length (n = 130–200 segments) in the basal, HR− and HR+ luminal cells (130–300 cells measured from three independent experiments). Changes in G1 (magenta) or S/G2/M (green) fluorescence intensity during 24 h imaging in a representative (c) proliferative or (d) differentiated cell, n = 130–300 cells measured over three independent experiments. e Schematic of Ts workflow. f Representative immunofluorescent images of CldU+ (green) IdU+ (cyan) cells, with basal marker Keratin 5 (K5, red). Scale bar = 25 µm. g Schematic of Tc workflow. h Representative immunofluorescent images of CldU+ (green) IdU+ (cyan) cells, with basal marker K5 (red). Arrows show IdU+, arrowheads show CldU+ and hollow arrows show CldU+IdU+ cells. Scale bar = 25 µm. i The diagram depicts the calculated/estimated length of the different cell cycle phases as a mean value of all proliferating cells in the mammary epithelium in vivo. j Bar graph showing the length of Ts (n = 7) and Tc (n = 5); mean ± SEM. k Schematic of the CFC assay and bar graph depicting clonogenic capacity at different phases of the cell cycle for basal, HR− and HR+ luminal colonies