Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
33
pubmed:dateCreated
1992-12-22
pubmed:abstractText
This study investigates the relationship between human erythrocyte glucose transport protein (GLUT1) oligomeric structure and glucose transporter function. Oligomeric structure was analyzed by hydrodynamic studies of cholate-solubilized GLUT1, by chemical cross-linking studies of membrane-resident GLUT1 and by using conformation-specific antibodies. Transporter function (substrate binding) was analyzed by equilibrium cytochalasin B and D-glucose binding measurements. Erythrocyte-resident glucose transporter is a GLUT1 homotetramer, binds 1 mol of cytochalasin B/2 mol of GLUT1, and presents at least two binding sites to D-glucose. Native structure and function appear to be stabilized by intramolecular disulfide bonds and are preserved during GLUT1 purification by the omission of reductant. Native structure is independent of in vitro and in vivo membrane GLUT1 density but is transformed to dimeric GLUT1 by alkaline reduction. Dimeric GLUT1 binds 1 mol of cytochalasin B/mol of GLUT1, presents a single population of binding sites to D-glucose, and is obtained upon GLUT1 purification in the presence of reductant. Native structure and function are restored by treatment of dimeric GLUT1 with glutathione-disulfide (K0.5 glutathione disulfide = 29 microM). We propose that native structure is established prior to transporter translocation to the plasma membrane and that intrasubunit disulfide bonds promote cooperative subunit interactions that stabilize transporter structure and function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
23829-38
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:1429721-Binding Sites, pubmed-meshheading:1429721-Chromatography, Gel, pubmed-meshheading:1429721-Cytochalasin B, pubmed-meshheading:1429721-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:1429721-Erythrocyte Membrane, pubmed-meshheading:1429721-Erythrocytes, pubmed-meshheading:1429721-Glucose, pubmed-meshheading:1429721-Glutathione, pubmed-meshheading:1429721-Glutathione Disulfide, pubmed-meshheading:1429721-Humans, pubmed-meshheading:1429721-Immunoglobulin G, pubmed-meshheading:1429721-Kinetics, pubmed-meshheading:1429721-Macromolecular Substances, pubmed-meshheading:1429721-Models, Structural, pubmed-meshheading:1429721-Molecular Weight, pubmed-meshheading:1429721-Monosaccharide Transport Proteins, pubmed-meshheading:1429721-Oxidation-Reduction, pubmed-meshheading:1429721-Protein Binding, pubmed-meshheading:1429721-Protein Denaturation
pubmed:year
1992
pubmed:articleTitle
Glucose transporter oligomeric structure determines transporter function. Reversible redox-dependent interconversions of tetrameric and dimeric GLUT1.
pubmed:affiliation
Program in Molecular Medicine, University of Massachusetts Medical Center, Worcester 10605.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.