The Role of Adenine Nucleotide Translocase in the Mitochondrial Permeability Transition

The mitochondrial permeability transition, a Ca(2+)-induced significant increase in permeability of the inner mitochondrial membrane, plays an important role in various pathologies. The mitochondrial permeability transition is caused by induction of the permeability transition pore (PTP). Despite significant effort, the molecular composition of the PTP is not completely clear and remains an area of hot debate. The Ca(2+)-modified adenine nucleotide translocase (ANT) and F(0)F(1) ATP synthase are the major contenders for the role of pore in the PTP. This paper briefly overviews experimental results focusing on the role of ANT in the mitochondrial permeability transition and proposes that multiple molecular entities might be responsible for the conductance pathway of the PTP. Consequently, the term PTP cannot be applied to a single specific protein such as ANT or a protein complex such as F(0)F(1) ATP synthase, but rather should comprise a variety of potential contributors to increased permeability of the inner mitochondrial membrane.