The mitochondrion is a multifunctional organelle.

During mitochondrial bioenergetics, acetyl-CoA converted from food molecules is oxidized to produce ATP. In addition to ATP production, mitochondria play essential roles in cell signaling including nutrient sensing, redox signaling, cell death, and many other functions [3, 7]. Note that biosynthetic pathways in mitochondria [4] are omitted in the diagram. ADP, adenosine diphosphate; AMP, adenosine monophosphate; CoA, coenzyme A; ETC, electron transport chain; TCA, tricarboxylic acid.