The process of autophagy (literally “self-eating”) is so vital to our survival that it was the focus of the 2016 Nobel Prize in Physiology or Medicine announced in October. Winner Yoshinori Ohsumi described the discovery of this complex process as a surprise. He watched as cells wrapped entire proteins and organelles in a protective membrane””and then shredded them to pieces with enzymes. It was the equivalent of watching a wrecking ball take down a skyscraper, reducing a majestic work of architecture into a pile of bricks.
The destruction seemed counterintuitive, even dangerous. The mantra of cellular biology up to that point had been that building proteins””not destroying them””was the key to health and survival. The controlled but nonetheless devastating demolition of these structures into which so much energy and resources had been poured was perplexing. Wouldn’t this starving cell prefer to have all of its organelles””just as a body would prefer to have all of its organs? Why, in the face of adversity, would a cell demolish something it had worked very hard to build?
As Ohsumi’s team investigated further, the metaphor used for three decades changed: Autophagy isn’t cellular self-cannibalism so much as it is cellular pruning. “Organisms never waste precious resources without good reason,” Ohsumi said, “and degradation is a process essential for the creation of new life.” At its core this process was one of destruction, but it was not reckless. A cell that was indiscriminately destroying pieces of itself was not going to last long, but one that could select old, broken, misshapen, or malignant proteins and recycle them into something new would flourish.
Read it all from CT.