Glycophorin A dimerization and band 3 interaction during erythroid membrane biogenesis: in vivo studies in human glycophorin A transgenic mice

Citation
I. Auffray et al., Glycophorin A dimerization and band 3 interaction during erythroid membrane biogenesis: in vivo studies in human glycophorin A transgenic mice, BLOOD, 97(9), 2001, pp. 2872-2878
Citations number
42
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Hematology,"Cardiovascular & Hematology Research
Journal title
BLOOD
ISSN journal
0006-4971 → ACNP
Volume
97
Issue
9
Year of publication
2001
Pages
2872 - 2878
Database
ISI
SICI code
0006-4971(20010501)97:9<2872:GADAB3>2.0.ZU;2-M
Abstract
Band 3 and glycophorin A (GPA) are the 2 most abundant integral proteins in the human erythrocyte membrane. Earlier studies suggested that the 2 prote ins may associate not only in the mature erythrocyte membrane, but also dur ing their posttranslational processing and intracellular trafficking. The p urpose of this study was to directly examine the CPA-band 3 interaction in vivo and determine the nature of this association during erythroid membrane biogenesis. Transgenic mice were generated expressing the human glycophori n A gene and were used to examine how the induction of hu-man GPA expressio n affected the levels of murine GPA and band 3 expression in the red cell m embrane. Murine CPA expression was reduced in erythrocytes expressing human GPA, whereas the level of band 3 expression remained constant, implying a tight coupling of band 3 and GPA expression in the membrane of mature red c ells. In vivo GPA dimerization was not modulated solely by the GPA transmem brane motif, but the distance between this motif and the basic residues on the cytoplasmic side of the transmembrane domain may also be important. In addition, GPA monomers with varying degrees of glycosylation dimerized, pro viding clear evidence that carbohydrate structures on the extracellular dom ain do not affect dimerization. The association between the multiple transm embrane-spanning protein, band 3, and the single transmembrane-spanning sia loglycoprotein, GPA, may serve as a model for interactions of other multi-p ass and single-pass polypep tides during membrane biogenesis. (Blood, 2001; 91:2872-2878) (C) 2001 by The American Society of Hematology.