4j9u
From Proteopedia
Crystal Structure of the TrkH/TrkA potassium transport complex
Structural highlights
FunctionTRKH_VIBPA Low-affinity potassium transport system. Interacts with trk system potassium uptake protein TrkA and requires TrkE for transport activity. Selective for permeation of potassium ion and rubidium ion over smaller ions such as natrium or litium. Publication Abstract from PubMedTrkH 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. Gating of the TrkH ion channel by its associated RCK protein TrkA.,Cao Y, Pan Y, Huang H, Jin X, Levin EJ, Kloss B, Zhou M Nature. 2013 Apr 18;496(7445):317-22. doi: 10.1038/nature12056. PMID:23598339[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. Loading citation details.. Citations No citations found See AlsoReferences
|
| |||||||||||||||||||
