Highly purified adenylate translocase (ANT) from rat heart mitochondria was functionally reconstituted as ATP/ADP exchange carrier in asotectin/cardiolipin vesicles. The ANT preparations used were free of porin, cyclophilin D, and Bax as analysed immunologically and by activity measurements. After pre-loading the ANT-containing proteoliposomes with ATP, malate or AMP, a gradual release of the trapped compounds by increasing the external Ca2+ concentrations could be demonstrated. N-Methyl-Val-4- cyclosporin did not inhibit the Ca2+ dependent release of internal substances from ANT liposomes. This inhibitor was found to be specific for the mitochondrial permeability transition pore (MTP) in intact mitochondria or reconstituted MTP-like protein complexes (e.g. hexokinase, porin, ANT complex). However, ADP in concentrations > 20 gM inhibited the liberation of internal compounds, while in contrast, atractyloside (30 μM) and HgCl2 (5 μM) both induced permeability of the ANT-containing liposomes resulting in a release of trapped substances. These results strongly suggest that ANT itself is capable to adopt a pore-like structure under conditions known to induce the permeability transition in mitochondria.
Rück, A., Dolder, M., Wallimann, T., & Brdiczka, D. (1998). Reconstituted adenine nucleotide translocase forms a channel for small molecules comparable to the mitochondrial permeability transition pore. FEBS Letters, 426(1), 97–101. https://doi.org/10.1016/S0014-5793(98)00317-2