Mitochondrial network: electric cable and more

Abstract

Mitochondria in a cell can unite and organize complex extended structures that extend over the entire cellular volume, ensuring a uniform supply of energy to cellular compartments with ATP synthesized in the mitochondria. In accordance with the chemiosmotic concept, the energy of oxidation of respiratory substrates is largely stored in the form of an electrical potential difference on the inner membrane of mitochondria. The theory of the functioning of extended mitochondrial structures as intracellular electrical wires suggests that mitochondria provide the fast delivery of electrical energy through the cellular volume, with following use of this energy for ATP synthesis, thereby speeding up the process of ATP delivery compared to the rather slow diffusion of ATP in the cell. The analytical review gives the history of the cable theory, solved and unsolved critical problems, the lability of the mitochondrial network and the role of oxidative stress in this process. In addition to the already proven functioning of extended mitochondrial structures as electrical cables, a few of additional functions are proposed, in particular, the hypothesis is put forward that mitochondrial networks provide a uniform distribution of redox potential throughout the cell, which can change in pathological conditions during fragmentation of the mitochondrial reticulum. A few of pathologies accompanied by a violation of the redox status and the participation of mitochondria in them are considered.