https://phys.org/news/2018-07-mighty-mitochondria-flex-dna-power.html

The findings are significant because aging causes cells to break down, leading to diseases such as cancer and Alzheimer's. Understanding the cell's inner workings opens opportunities for medical advances that can help save lives. The study appears today in the journal Cell Metabolism.

"Mitochondria have their own DNA that presumably comes from ancient bacteria that joined our cells a long time ago. We didn't know that our mitochondrial DNA encoded messages to control the nucleus. In fact, the nucleus has been long thought to hold all our genetic blueprint for building and operating a cell," Lee said. "This is a fundamental discovery that integrates our two genomes as a co-evolved genetic system and may have a lasting impact for a broad range of scientific and medical fields."