Upon realizing there isn’t much food around, our body starts rummaging through our cells in a salvage operation, looking for anything we don’t need—defective proteins, malfunctioning mitochondria, and other stuff that isn’t working anymore. It clears out the junk and upcycles it, turning it into fuel or new building materials, thereby renewing our cells. So, autophagy plays two major roles: nutrient recovery and quality control. The conservation of autophagy machinery over a billion years of biological evolution underscores the importance of this universal recycling program,234 recognized in
...more
