Here's the important point: there are plenty of stressors that will activate longevity genes without damaging the cell, including certain types of ex… - David A. Sinclair

When the Sir2 enzyme is sitting on the mating-type genes, they remain silent and the cell continues to mate and reproduce. But when a DNA break occurs, Sir2 is recruited to the break to remove the acetyl tags from the histones at the DNA break. This bundles up the histones to prevent the frayed DNA from being chewed back and to help recruit other repair proteins. Once the DNA repair is complete, most of the Sir2 protein goes back to the mating-type genes to silence them and restore fertility. That is, unless there is another emergency, such as the massive genome instability that occurs when ERCs accumulate in the nucleoli of old yeast cells.

The Information Theory of Aging starts with the primordial survival circuit we inherited from our distant ancestors.

What's the upward limit? I don't think there is one. Many of my colleagues agree.14 There is no biological law that says we must age.15 Those who say there is don't know what they're talking about. We're probably still a long way off from a world in which death is a rarity, but we're not far from pushing it ever farther into the future.