Scientists Discover How a Common Amino Acid Boosts Cell Energy
Researchers have identified a direct link between what we eat and how our cells produce energy. The nutrient leucine, an amino acid found in protein rich foods like meat, dairy, and beans, acts as a signal to slow the breakdown of proteins on the outer surface of mitochondria. Mitochondria are the structures inside cells that generate energy. By protecting these surface proteins, leucine helps mitochondria expand their workforce of internal proteins and ramp up energy production. Experiments reveal a chain reaction: leucine blocks a sensor called GCN2, which in turn reduces levels of a molecule named SEL1L near mitochondria. Without SEL1L tagging them for destruction, the surface proteins remain stable. The findings may explain why defects in leucine processing harm fertility in worms and help certain lung cancer cells resist therapies that block mitochondrial protein import. Understanding this nutrient sensing pathway could lead to new strategies for treating metabolic diseases and cancer.
Li et al. uncover a connection between metabolic cues and mitochondrial protein degradation, showing that specifically leucine stabilizes ou