Autophagy unveiled

In cell biology research it seems that building gets more attention than destruction: work on the cell cycle leapt ahead while apoptosis research was in its infancy, and protein synthesis pathways were well established when autophagy was, for most researchers, a word that drew blank stares.

Thus the molecular description of autophagy is a relatively recent phenomenon (Klionsky and Emr, 2000). But the morphology came early. Autophagy is the destructive process in which a double membrane envelops cytoplasm and organelles before targeting them to lysosomes for destruction. It was first spotted in differentiating kidney cells as they redirected their metabolic energies (Clark, 1957).

A robust model was established by Ashford and Porter (1962), who spotted autophagy when glucagon was perfused into rat livers. Glucagon is made in response to low blood sugar levels,...