The standard eukaryotic cell cycle consists of four phases: G1, S, G2, and M phases. There are three phase transitions in a cell cycle: G1/S to initiate DNA synthesis, G2/M to enter mitosis ...
Checkpoints are depicted as thick red bars. The stages of the cell cycle (G1: Gap 1, S: DNA synthesis, G2: Gap 2, and M: mitosis) are indicated. Tumor suppressors act to maintain checkpoints ...