FIG. 1.

Mitochondrial energy metabolism and solute exchange. Schematic visualization of the ATP-generating mitochondrial oxidative phosphorylation system (yellow) and TCA cycle. Solute exchangers are indicated in different colors. See main text for details. This figure was compiled by integrating information from (160, 188, 185, 227, 315, 335). Δψ, trans-MIM electrical gradient; ΔpH, trans-MIM pH gradient; AA, amino acids; ADP, adenosine diphosphate; ANT, adenine nucleotide translocator; AQP8, aquaporin-8; ATP, adenosine triphosphate; C, cytochrome-c; CI-CV, complex I–V; FAs, fatty acids; Gln, glutamine; IMS, intermembrane space; KHE, K⁺/H⁺ exchanger; Kv1.3, mitochondrial voltage-activated K⁺ channel of the Kv1.3 type; LETM1, leucine zipper-EF-hand-containing transmembrane protein 1; mBK_Ca, mitochondrial Ca²⁺-regulated K⁺ large conductance channel; MCU, mitochondrial calcium uniporter; mHCX, mitochondrial H⁺/Ca²⁺ exchanger; MIM, mitochondrial inner membrane; mK_ATP, mitochondrial ATP-activated K⁺ channel; mNCX, mitochondrial Na⁺/Ca²⁺ exchanger; mNHE, mitochondrial Na⁺/H⁺ exchanger; MOM, mitochondrial outer membrane; mPTP, mitochondrial permeability transition pore; mRYR, mitochondrial ryanodine receptor; mSK_Ca, mitochondrial small conductance Ca²⁺-activated K⁺ channel; NNT, nicotinamide nucleotide transhydrogenase; OXPHOS, oxidative phosphorylation; PiC, Pi/H⁺ symporter; PMF, proton-motive force; Pyr, pyruvate; Q, Coenzyme Q₁₀; RaM, rapid mode of Ca²⁺ uptake; ROS, reactive oxygen species; TCA, tricarboxylic acid; UCP, uncoupling protein. Color images are available online.