How the cell’s power station survives attacks

Salk Institute News, 01/18/2016

Salk scientists discover how mitochondria recover after damage, offering clues to cancer, diabetes and brain disease.
Mitochondria, the power generators in our cells, are essential for life. When they are under attack – from poisons, environmental stress or genetic mutations – cells wrench these power stations apart, strip out the damaged pieces and reassemble them into usable mitochondria. Now, scientists at the Salk Institute have uncovered an unexpected way in which cells trigger this critical response to threats, offering insight into disorders such as mitochondrial disease, cancer, diabetes and neurodegenerative disease – particularly Parkinson’s disease, which is linked to dysfunctional mitochondria. The work appears January 15, 2016 in Science. In the new work, the Salk team found that when cells are exposed to mitochondria damage, a central cellular fuel gauge, the enzyme AMPK, sends an emergency alert to mitochondria instructing them to break apart into many tiny mitochondrial fragments. Interestingly, AMPK is activated by the widely used diabetes therapeutic metformin, as well as exercise and a restricted diet. The new findings suggest that some of the benefits from these therapies may result from their effects in promoting mitochondrial health.