Linked Life Data

10545179

Source:http://linkedlifedata.com/resource/pubmed/id/10545179

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
44
pubmed:dateCreated
1999-12-22
pubmed:abstractText
AE1, the chloride/bicarbonate anion exchanger of the erythrocyte plasma membrane, is highly sensitive to inhibition by stilbene disulfonate compounds such as DIDS (4,4'-diisothiocyanostilbene-2, 2'-disulfonate) and DNDS (4,4'-dinitrostilbene-2,2'-disulfonate). Stilbene disulfonates recruit the anion binding site to an outward-facing conformation. We sought to identify the regions of AE1 that undergo conformational changes upon noncovalent binding of DNDS. Since conformational changes induced by stilbene disulfonate binding cause anion transport inhibition, identification of the DNDS binding regions may localize the substrate binding region of the protein. Cysteine residues were introduced into 27 sites in the extracellular loop regions of an otherwise cysteineless form of AE1, called AE1C(-). The ability to label these residues with biotin maleimide [3-(N-maleimidylpropionyl)biocytin] was then measured in the absence and presence of DNDS. DNDS reduced the ability to label residues in the regions around G565, S643-M663, and S731-S742. We interpret these regions either as (i) part of the DNDS binding site or (ii) distal to the binding site but undergoing a conformational change that sequesters the region from accessibility to biotin maleimide. DNDS alters the conformation of residues outside the plane of the bilayer since the S643-M663 region was previously shown to be extramembranous. Upon binding DNDS, AE1 undergoes conformational changes that can be detected in extracellular loops at least 20 residues away from the hydrophobic core of the lipid bilayer. We conclude that the TM7-10 region of AE1 is central to the stilbene disulfonate and substrate binding region of AE1.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14565-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Trapping of inhibitor-induced conformational changes in the erythrocyte membrane anion exchanger AE1.
pubmed:affiliation
Department of Physiology, Membrane Transport Group and MRC Group in Molecular Biology of Membranes, University of Alberta, Edmonton, Alberta, Canada T6G 2H7.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't