Mitochondria

In his rollicking 2005 book, Power, Sex and Suicide: Mitochondria and the Meaning of Life, Nick Lane illustrates how mitochondria rule the biological world, something we mitochondrial biologists have always suspected. The title of the book references what mitochondria can do—they generate ATP (power), their DNA is maternally inherited (sex), and they invoke programmed cell death (suicide). The “meaning of life” alludes to the evolution of the first eukaryote. A current leading hypothesis, the endosymbiont theory, suggests that ∼2 billion years ago two prokaryotes, an archaeon and an α-proteobacterium, developed a biological relationship in which both were mutually dependent on one another for nutritional requirements. Eventually, the archaeon, the host cell, acquired the α-proteobacterium, which became the primordial mitochondria. It is often assumed that the original symbiosis was based on the α-proteobacterium detoxifying oxygen and providing copious amount of ATP for the host cell. However, current data indicate that …