Forster, I C; Köhler, K; Biber, J; Murer, H (2002). Forging the link between structure and function of electrogenic cotransporters: the renal type IIa Na+/Pi cotransporter as a case study. Progress in Biophysics and Molecular Biology, 80(3):69-108.
Full text not available from this repository.
Electrogenic cotransporters are membrane proteins that use the electrochemical gradient across the cell membrane of a cosubstrate ion, for example Na(+) or H(+), to mediate uphill cotransport of a substrate specific to the transport protein. The cotransport process involves recognition of both cosubstrate and substrate and translocation of each species according to a defined stoichiometry. Electrogenicity implies net movement of charges across the membrane in response to the transmembrane voltage and therefore, in addition to isotope flux assays, the cotransport kinetics can be studied in real-time using electrophysiological methods. As well as the cotransport mode, many cotransporters also display a uniport or slippage mode, whereby the cosubstrate ions translocate in the absence of substrate. The current challenge is to define structure-function relationships by identifying functionally important elements in the protein that confer the transport properties and thus contribute to the ultimate goal of having a 3-D model of the protein that conveys both structural and functional information. In this review we focus on a functional approach to meet this challenge, based on a combination of real-time electrophysiological assays, together with molecular biological and biochemical methods. This is illustrated, by way of example, using data obtained by heterologous expression of the renal Na(+)-coupled inorganic phosphate cotransporter (NaP(i)-IIa) for which structure-function relationships are beginning to emerge.
|Item Type:||Journal Article, refereed, original work|
|Communities & Collections:||04 Faculty of Medicine > Institute of Physiology|
07 Faculty of Science > Institute of Physiology
|DDC:||570 Life sciences; biology|
|Date:||01 November 2002|
|Deposited On:||11 Feb 2008 13:22|
|Last Modified:||23 Nov 2012 13:30|
Users (please log in): suggest update or correction for this item
Repository Staff Only: item control page