Reconstitution of intramembrane particles in recombinants of erythrocyte protein band 3 and lipid: effects of spectrin-actin association.
AUTOR(ES)
Yu, J
RESUMO
The integral membrane protein Band 3 of the human erythrocyte, either purified or in a crude Triton X-100 extract of ghosts, was combined with egg lecithin in a cholate solution. During dialysis to remove cholate, lipid bilayer vesicles formed in which Band 3 existed as a dimer and in which intramembrane particles indistinguishable from those in the native membrane were exposed by freeze-fracturing. The recombinant vesicles were stable in both high and low salt concentrations, sedimented at a density that increased in prportion to their protein content, and bound spectrin-actin extracted from erythrocyte ghosts. When spectrin-actin was associated with the vesicles, the behavior of the recombinant intramembrane particles simulated that of the erythrocyte ghost intramembrane particles: they were dispersed at pH 7.6 and aggregrated at pH 5-5.5. Thus, some of the characteristics of the native membrane have been reconstituted in the recombinant.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=431254Documentos Relacionados
- Irreversible deformation of the spectrin-actin lattice in irreversibly sickled cells.
- Protein 4.1 deficiency associated with an altered binding to the spectrin-actin complex of the red cell membrane skeleton.
- Hydrodynamic steering effects in protein association.
- Reconstitution of spectrin-deficient, spherocytic mouse erythrocyte membranes.
- Molecular analysis of insertion/deletion mutations in protein 4.1 in elliptocytosis. I. Biochemical identification of rearrangements in the spectrin/actin binding domain and functional characterizations.