6gci

Publication Abstract from PubMed

Mitochondrial ADP/ATP carriers transport ADP into the mitochondrial matrix for ATP synthesis, and ATP out to fuel the cell, by cycling between cytoplasmic-open and matrix-open states. The structure of the cytoplasmic-open state is known, but it has proved difficult to understand the transport mechanism in the absence of a structure in the matrix-open state. Here, we describe the structure of the matrix-open state locked by bongkrekic acid bound in the ADP/ATP-binding site at the bottom of the central cavity. The cytoplasmic side of the carrier is closed by conserved hydrophobic residues, and a salt bridge network, braced by tyrosines. Glycine and small amino acid residues allow close-packing of helices on the matrix side. Uniquely, the carrier switches between states by rotation of its three domains about a fulcrum provided by the substrate-binding site. Because these features are highly conserved, this mechanism is likely to apply to the whole mitochondrial carrier family.

The Molecular Mechanism of Transport by the Mitochondrial ADP/ATP Carrier.,Ruprecht JJ, King MS, Zogg T, Aleksandrova AA, Pardon E, Crichton PG, Steyaert J, Kunji ERS Cell. 2019 Jan 2. pii: S0092-8674(18)31517-4. doi: 10.1016/j.cell.2018.11.025. PMID:30611538^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.