Fig. 1.

Mitochondrial dynamics: the process of fission and fusion. Mitochondrial fission is regulated by Drp1 and FIS1, which compress and separate mitochondrial tubules. Under conditions of low energy demand, fission facilitates uncoupled respiration, resulting to reduced ATP synthesis. Oppositely, during fusion, Mfn1/2 and OPA1 integrate the OMMs and IMMs. Mitochondrial fusion is stimulated by energy demand and stress and leads to upregulation of metabolic competence. Drp1, dynamin-like/related protein 1; FIS1, mitochondrial fission 1 protein; Mfn1, mitofusin 1; Mfn2, mitofusin 2; OPA1, optic atrophy 1; OMM; outer mitochondrial membrane; IMM, inner mitochondrial membrane