title: Reassociation of ankyrin with band 3 in erythrocyte membranes and in lipid vesicles.
abstract: The binding of human erythrocyte ankyrin (band 2.1) to the erythrocyte membrane has been characterized by reassociating purified ankyrin with ankyrin-depleted inside-out vesicles. Ankyrin reassociates at high affinity with a limited number of protease-sensitive sites located only on the cytoplasmic side of the erythrocyte membrane. Depleting the vesicles of band 4.2 does not affect their binding capacity. A 45,000-dalton polypeptide derived from the cytoplasmic portion of band 3 competitively inhibits the binding of ankyrin to inside-out vesicles. Although the bulk of band 3 molecules appear to have the potential for binding ankyrin, nly a fraction of the band 3 molecules in native membranes or in reconstituted liposomes actually provides accessible high affinity ankyrin binding sites.
mesh_terms: D001457:Anion Exchange Protein 1, Erythrocyte; D017487:Ankyrins; D001798:Blood Proteins / Q000378:metabolism*; D002918:Chymotrypsin; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D005613:Freeze Etching; D006801:Humans; D007700:Kinetics; D046911:Macromolecular Substances; D008563:Membrane Lipids / Q000097:blood*; D008565:Membrane Proteins / Q000378:metabolism*; D008854:Microscopy, Electron; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D011485:Protein Binding
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D017487:Ankyrins; D001798:Blood Proteins; D046911:Macromolecular Substances; D008563:Membrane Lipids; D008565:Membrane Proteins; D010446:Peptide Fragments; D002918:Chymotrypsin