Lysosomes are versatile garbage disposals. In addition to taking in shrouded material, they can also pull in individual proteins through special portals on their surface. Lysosomes can even extend a mouthlike projection from their membrane and chew off pieces of a cell.
The shredded debris that streams out of the lysosomes is not useless waste. A cell uses the material to build new molecules, gradually recreating itself from old parts. “Every three days, you basically have a new heart,” said Dr. Ana Maria Cuervo, a molecular biologist at Albert Einstein College of Medicine.
This self-destruction may seem like a reckless waste of time and energy. Yet it is essential for our survival, and in many different ways. Proteasomes destroy certain proteins quickly, allowing them to survive for only about half an hour. That speed allows cells to keep tight control over the concentrations of the proteins. By tweaking the rate of destruction, it can swiftly raise or lower the number of any kind of protein.
In my opinion, this has some major implications for the design of self-repairing autogenous systems, not only physical but informational.
[Added:]
good post on NextBigFuture covering that and SENS applications.