Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Water and urea permeation pathways of the human excitatory amino acid transporter EAAT1
Author: Vandenberg, R.
Handford, C.
Campbell, E.
Ryan, R.
Yool, A.
Citation: Biochemical Journal, 2011; 439(2):333-340
Publisher: Portland Press
Issue Date: 2011
ISSN: 0264-6021
Statement of
Robert J. Vandenberg, Cheryl A. Handford, Ewan M. Campbell, Renae M. Ryan and Andrea J. Yool
Abstract: Glutamate transport is coupled to the co-transport of 3 Na(+) and 1 H(+) followed by the counter-transport of 1 K(+). In addition, glutamate and Na(+) binding to glutamate transporters generates an uncoupled anion conductance. The human glial glutamate transporter EAAT1 (excitatory amino acid transporter 1) also allows significant passive and active water transport, which suggests that water permeation through glutamate transporters may play an important role in glial cell homoeostasis. Urea also permeates EAAT1 and has been used to characterize the permeation properties of the transporter. We have previously identified a series of mutations that differentially affect either the glutamate transport process or the substrate-activated channel function of EAAT1. The water and urea permeation properties of wild-type EAAT1 and two mutant transporters were measured to identify which permeation pathway facilitates the movement of these molecules. We demonstrate that there is a significant rate of L-glutamate-stimulated passive and active water transport. Both the passive and active L-glutamate-stimulated water transport is most closely associated with the glutamate transport process. In contrast, L-glutamate-stimulated [(14)C]urea permeation is associated with the anion channel of the transporter. However, there is also likely to be a transporter-specific, but glutamate independent, flux of water via the anion channel.
Keywords: anion channel; glutamate transport; urea; water transport.
Rights: © The Authors Journal compilation © 2011 Biochemical Society
RMID: 0020113635
DOI: 10.1042/BJ20110905
Grant ID:
Appears in Collections:Physiology publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.