4J9U

Crystal Structure of the TrkH/TrkA potassium transport complex

Summary for 4J9U

• Entry DOI: 10.2210/pdb4j9u/pdb
• Related: 4J9V
• Descriptor: Trk system potassium uptake protein TrkH, Potassium uptake protein TrkA, HEXATANTALUM DODECABROMIDE, ... (5 entities in total)
• Functional Keywords: rck domain, potassium transport, membrane protein, structural genomics, psi-biology, new york consortium on membrane protein structure, nycomps, transport protein
• Biological source: Vibrio parahaemolyticus; More
• Cellular location: Cell inner membrane; Multi-pass membrane protein (By similarity): Q87TN7
• Total number of polymer chains: 8
• Total formula weight: 452801.57

Authors

Cao, Y.,Jin, X.,Huang, H.,Levin, E.J.,Zhou, M.,New York Consortium on Membrane Protein Structure (NYCOMPS) (deposition date: 2013-02-17, release date: 2013-04-03, Last modification date: 2024-10-30)

Primary citation

Cao, Y.,Pan, Y.,Huang, H.,Jin, X.,Levin, E.J.,Kloss, B.,Zhou, M.
Gating of the TrkH ion channel by its associated RCK protein TrkA.
Nature, 496:317-322, 2013

PubMed Abstract: TrkH belongs to a superfamily of K(+) transport proteins required for growth of bacteria in low external K(+) concentrations. The crystal structure of TrkH from Vibrio parahaemolyticus showed that TrkH resembles a K(+) channel and may have a gating mechanism substantially different from K(+) channels. TrkH assembles with TrkA, a cytosolic protein comprising two RCK (regulate the conductance of K(+)) domains, which are found in certain K(+) channels and control their gating. However, fundamental questions on whether TrkH is an ion channel and how it is regulated by TrkA remain unresolved. Here we show single-channel activity of TrkH that is upregulated by ATP via TrkA. We report two structures of the tetrameric TrkA ring, one in complex with TrkH and one in isolation, in which the ring assumes two markedly different conformations. These results suggest a mechanism for how ATP increases TrkH activity by inducing conformational changes in TrkA.

PubMed: 23598339
DOI: 10.1038/nature12056

Experimental method

X-RAY DIFFRACTION (3.8 Å)