USC researchers focused on the two parts of the cell that carry DNA: the nucleus and the mitochondria. Most genetic material resides in the nucleus, which is the largest component of the cell. Its DNA sends coded templates telling the cell what to do. Smaller mitochondria function as energy-producing factories, turning food into fuel to power the cell. But size can be misleading. The mitochondria also contain DNA, all of it inherited from the mother, and as the new study shows, they are not just taking orders from the nucleus.
Working with human cells, the scientists discovered that when a cell is under stress and starved for nutrients, MOTS-c, a small protein encoded in the mitochondria DNA, moves into the nucleus to control genes and turn on a defensive system, including an antioxidant response.
“Most diseases are due to aging, and aging leads to a breakdown in cell functions,” Lee said. “When things go wrong in the body, it’s because some mechanism in the body went wrong. So, understanding how cells age means we have more insight into how the damage occurs and how we can prevent or fix it,” he said.
