EDITORIAL COMMENT: All metabolic roads lead to mitochondrial (dys)-function

摘要

Mitochondria lie in the heart of cell life and death [1]. These intracellular organelles provide the energy for almost all cellular processes. Taking the beating heart as an example, the myocardium requires approximately 30 kg/day of ATP via oxidative phosphorylation at the inner mitochondrial membrane. From an evolutionary point of view it is fascinating to realize that mitochondria are thought to have evolved from a bacterial progenitor around the same time in evolution when another basic cellular structure, the chloroplast, was created to generate oxidizeable fuels from the sun. Both mitochondria and chloroplasts are the only structures in cells to possess their own DNA, which is distinct from the somatic DNA of the nucleus. This does not, however, lead to a relative independent function within the cell structure. Mitochondrial DNA (mtDNA; 37 genes) encodes only for a few necessary proteins. A total of about 850 genes encoded by the nucleus and transported to the mitochondria are required for optimal function. This leads to a complex symbiosis between both entities that are partly dictated by a different set of DNA: the cell with all its metabolites and fuels on the one hand and the mitochondrion to generate the necessary energy-rich phosphates on the other hand.