Structural highlights
Function
Q5SIA2_THET8
Publication Abstract from PubMed
To fully understand the transport mechanism of Na+/H+ exchangers, it is necessary to clearly establish the global rearrangements required to facilitate ion translocation. Currently, two different transport models have been proposed. Some reports have suggested that structural isomerization is achieved through large elevator-like rearrangements similar to those seen in the structurally unrelated sodium-coupled glutamate-transporter homolog GltPh. Others have proposed that only small domain movements are required for ion exchange, and a conventional rocking-bundle model has been proposed instead. Here, to resolve these differences, we report atomic-resolution structures of the same Na+/H+ antiporter (NapA from Thermus thermophilus) in both outward- and inward-facing conformations. These data combined with cross-linking, molecular dynamics simulations and isothermal calorimetry suggest that Na+/H+ antiporters provide alternating access to the ion-binding site by using elevator-like structural transitions.
Crystal structures reveal the molecular basis of ion translocation in sodium/proton antiporters.,Coincon M, Uzdavinys P, Nji E, Dotson DL, Winkelmann I, Abdul-Hussein S, Cameron AD, Beckstein O, Drew D Nat Struct Mol Biol. 2016 Feb 1. doi: 10.1038/nsmb.3164. PMID:26828964[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Coincon M, Uzdavinys P, Nji E, Dotson DL, Winkelmann I, Abdul-Hussein S, Cameron AD, Beckstein O, Drew D. Crystal structures reveal the molecular basis of ion translocation in sodium/proton antiporters. Nat Struct Mol Biol. 2016 Feb 1. doi: 10.1038/nsmb.3164. PMID:26828964 doi:http://dx.doi.org/10.1038/nsmb.3164