5I6C

The structure of the eukaryotic purine/H+ symporter, UapA, in complex with Xanthine

Summary for 5I6C

• Entry DOI: 10.2210/pdb5i6c/pdb
• Descriptor: Uric acid-xanthine permease, XANTHINE, DODECYL-BETA-D-MALTOSIDE (3 entities in total)
• Functional Keywords: membrane protein eukaryotic uric acid/xanthine h+ symporter, transport protein
• Biological source: Aspergillus nidulans FGSC A4
• Cellular location: Cell membrane ; Multi-pass membrane protein : Q07307
• Total number of polymer chains: 2
• Total formula weight: 124755.71

Authors

Alguel, Y.,Amillis, S.,Leung, J.,Lambrinidis, G.,Capaldi, S.,Scull, N.J.,Craven, G.,Iwata, S.,Armstrong, A.,Mikros, E.,Diallinas, G.,Cameron, A.D.,Byrne, B. (deposition date: 2016-02-16, release date: 2016-04-27, Last modification date: 2024-11-13)

Primary citation

Alguel, Y.,Amillis, S.,Leung, J.,Lambrinidis, G.,Capaldi, S.,Scull, N.J.,Craven, G.,Iwata, S.,Armstrong, A.,Mikros, E.,Diallinas, G.,Cameron, A.D.,Byrne, B.
Structure of eukaryotic purine/H(+) symporter UapA suggests a role for homodimerization in transport activity.
Nat Commun, 7:11336-11336, 2016

PubMed Abstract: The uric acid/xanthine H(+) symporter, UapA, is a high-affinity purine transporter from the filamentous fungus Aspergillus nidulans. Here we present the crystal structure of a genetically stabilized version of UapA (UapA-G411VΔ1-11) in complex with xanthine. UapA is formed from two domains, a core domain and a gate domain, similar to the previously solved uracil transporter UraA, which belongs to the same family. The structure shows UapA in an inward-facing conformation with xanthine bound to residues in the core domain. Unlike UraA, which was observed to be a monomer, UapA forms a dimer in the crystals with dimer interactions formed exclusively through the gate domain. Analysis of dominant negative mutants is consistent with dimerization playing a key role in transport. We postulate that UapA uses an elevator transport mechanism likely to be shared with other structurally homologous transporters including anion exchangers and prestin.

PubMed: 27088252
DOI: 10.1038/ncomms11336

Experimental method

X-RAY DIFFRACTION (3.7 Å)