Figure 1.

Tight or loose models of cell death regulation. Signal processing analogy can be used – stimulus as an input signal, cellular mechanisms as a black box, top proteome changes as an output signal. Left (a): In the tight model, different stimuli cause significantly different states of the dying cell, and such a state can be traced back to the actual cause of death. Right (b): In the alternative loose model, different lethal stimuli result in a common, or very similar, state of the dying cell, and based on that state, it is hard to decipher death’s primary cause.