Cells poised to divide can delay their commitment to proliferate

For a cell to progress through the G1 phase of the cell cycle and divide, it must first integrate various signals. It emerges that cells in a ‘primed’ G1 state — characterized by intermediate activation of a transcription factor called E2F — can hold off making this commitment or even reverse back into G1. Intermediate activity of a protein called E2F puts cells in a ‘primed’ state before they either divide or reverse back to quiescence.