The p53 pulse encoder counts by topological necessity: theory, evidence, and the molecular origin of the 5.5-hour clock
After DNA damage, p53 does not signal how much damage there is by how much p53 there is: single cells fire a series of pulses whose amplitude is dose-invariant and whose number grows with dose. Why the encoder works this way has been open since the pulses were discovered. We show that the answer is topological. Pulse-g...