Exposure to 3 μM Cdk4 inhibitor caused NMuMG/Fucci2 cells to undergo G1 arrest or endoreplication in a cell-cycle phase dependent manner. When the drug was applied, the observed cells were in early G1 (A), late G1 (B), G1/S (C), and S/G2 (D) phases. Scale bar, 10 μm. (B) A white arrow indicates the endoreplication. (C and D) M, M phase. A solid arrow indicates a daughter cell, which was tracked. A solid arrowhead indicates the other daughter cell.
Sakaue-Sawano et al. BMC Cell Biology 2011 12:2 doi:10.1186/1471-2121-12-2