Decreased G3PDH binding to erythrocyte membranes in sickle cell disease

Several membrane abnormalities have been described in red cells from patients with sickle cell disease, responsible for chronic hemolytic anemia. We describe here a 35-50% inhibition of the binding of glyceraldehyde-3-phosphate dehydrogenase (G3PDH) to the membrane of sickle red cells. Varying the phosphorylation state of the membrane proteins did not change their affinity for the enzyme. Protein band 3 and the cytoplasmic domain of this protein isolated from sickle red cells showed normal interaction with the enzyme. The inhibition observed with intact membranes is not due to short term oxidation of membrane proteins, as various procedures inducing acute oxidative stress in normal membranes did not reproduce the inhibition of G3PDH binding. We conclude that the alteration of the binding of G3PDH to the membrane of sickle erythrocytes is probably related to long term processes involving cycles of HbS polymer formation.