Thin-section and critical-point-dried fracture-labeled preparations are used to determine the distribution and partition of glycophorin-associated wheat germ agglutinin (WGA) binding sites over protoplasmic and exoplasmic faces of freeze-fractured human erythrocyte membranes. Most wheat germ agglutinin binding sites are found over exoplasmic faces. Label is sparse over the protoplasmic faces. These results contrast with previous observations of the partition of band 3 component where biochemical analysis and fracture-label of concanavalin A (Con A) binding sites show preferential partition of this transmembrane protein with the protoplasmic face. Presence of characteristic proportions of WGA and Con A binding sites over each fracture face is interpreted to indicate the operation of a stochastic process during freeze-fracture. This process appears modulated by the relative expression of each transmembrane protein at either surface as well as by their association to components of the erythrocyte membrane skeleton.
Article| May 01 1982
Freeze-fracture cytochemistry: partition of glycophorin in freeze-fractured human erythrocyte membranes.
P P da Silva
M R Torrisi
Online ISSN: 1540-8140
Print ISSN: 0021-9525
J Cell Biol (1982) 93 (2): 463–469.
P P da Silva, M R Torrisi; Freeze-fracture cytochemistry: partition of glycophorin in freeze-fractured human erythrocyte membranes.. J Cell Biol 1 May 1982; 93 (2): 463–469. doi: https://doi.org/10.1083/jcb.93.2.463
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