Structural organisation of band 3 in Melanesian ovalocytes.
The diffusional freedom of human erythrocyte band 3 (anion exchanger 1) has been measured in membranes from normocytic and ovalocytic erythrocytes. A dramatic reorganisation of band 3 in the ovalocyte membranes is indicated by a markedly restricted rotational mobility. Extraction of spectrin from erythrocyte membranes had no effect on normocyte band 3 mobility, but partially relieved the restrictions on ovalocyte band 3 mobility. Further removal of ankyrin and band 4.2 resulted in an increase in the rotational mobility of both ovalocyte and normocyte band 3 to similar levels. The results suggest that the molecular basis of the unusual shape and decreased deformability of ovalocytes resides in an altered interaction of band 3 with one or more of the peripheral proteins. We present a model which illustrates a possible role for band 3 aggregation in controlling erythrocyte deformability.
Tilley
L
L
Department of Biochemistry, La Trobe University, Bundoora, Vic, Australia.
McPherson
R A
RA
Jones
G L
GL
Sawyer
W H
WH
D001457:Anion Exchange Protein 1, Erythrocyte / Q000737:chemistry* / Q000378:metabolism; D017487:Ankyrins / Q000302:isolation & purification; D001665:Binding Sites; D001798:Blood Proteins / Q000302:isolation & purification; D003598:Cytoskeletal Proteins; D004910:Erythrocyte Membrane / Q000737:chemistry / Q000378:metabolism; D004913:Erythrocytes, Abnormal / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008163:Luminescent Measurements; D008542:Melanesia; D008565:Membrane Proteins / Q000378:metabolism; D013049:Spectrin / Q000302:isolation & purification
D001457:Anion Exchange Protein 1, Erythrocyte; D017487:Ankyrins; D001798:Blood Proteins; D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; C044791:erythrocyte membrane band 4.2 protein; D013049:Spectrin