Phosphate metabolite regulation of spectrin interactions

The deformability of the erythrocyte membrane is believed to depend upon component interactions in the spectrin, actin and band 4.1 complex. Phosphate metabolites, such as 2,3-diphosphoglycerate (2,3 DPG) will dissociate spectrin from actin and band 4.1. This dissociation by 2,3 DPG is highly pH dependent but does not involve divalent cations, 2,3 DPG hydrolysis or spectrin dephosphorylation. In intact erythrocytes the concentrations of 2,3 DPG and the lipid, triphosphatidyl inositol, are sufficient to cause increased labilization in the spectrin, actin and band 4.1 network.