Mitochondria are cellular organelles that play an important role in making ATP (adenosine triphosphate), the molecular fuel that powers most cellular functions. These organelles originated over a billion years ago when a primitive archaeal cell entered into a symbiotic relationship with an ancestral bacterium. Over time, mitochondria became essential for metabolism and energy production, while transferring most of their genes to the host. As a result, they now rely on the host cell to supply most of their proteins, which are synthesized by ribosomes outside the organelle and must be properly delivered to mitochondria.
Biochemists uncover new rules of mitochondrial protein import
