Effects of intramembrane particle aggregation on erythrocyte membrane fluidity: an electron spin resonance study in normal and in dystrophic subjects.

Abstract

Mobilization and aggregation of intramembrane particles (IMPs) are physiological events observed in various cells. In erythrocyte membranes, aggregation of IMPs can be induced by the exposure of partially desprectrinized erythrocyte membranes to acidic pH. We investigated the association between IMPs aggregation, protein mobility, and membrane fluidity in erythrocyte membranes of healthy controls and Duchenne muscular dystrophy (DMD) patients by using electron spin resonance and specific spin labels for membrane proteins and lipids. In erythrocyte membranes of control subjects, the partial spectrin removal induced a decreased segmental motion of protein spin label indicating an increase of protein-protein interactions. Stearic acid spin labels 5- and 16-(N-oxyl-4,4'-dimethyloxazolidine) showed that the treatment induces an increase of membrane fluidity. In DMD patients, both treated and untreated erythrocyte membranes showed changes of membrane fluidity when compared to those of the controls. Our results suggest that defects in the interactions between skeletal proteins and/or between membrane and skeleton components may contribute to the alterations of erythrocyte membranes in DMD.

• Authors: G Ferretti, A Tangorra, G Curatola
• Journal: Experimental cell research (Exp Cell Res) Vol. 191 Issue 1 Pg. 14-21 (Nov 1990) ISSN: 0014-4827 [Print] United States
• PMID: 2171966 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Membrane Proteins
• Spin Labels
• Spectrin

Topics

• Electron Spin Resonance Spectroscopy
• Erythrocyte Membrane (metabolism, ultrastructure)
• Freeze Fracturing
• Humans
• Hydrogen-Ion Concentration
• Male
• Membrane Fluidity
• Membrane Proteins (metabolism)
• Muscular Dystrophies (blood)
• Protein Denaturation
• Spectrin (metabolism)
• Spin Labels
• Temperature