FIGURE 7.

Working model for glycation of spectrin induced by either glucose or ribose in human erythrocytes. In normal erythrocytes, glycolysis-derived ATP driving the ATP-dependent flippase maintains PS in the inner monolayer, enabling the PS-binding spectrin repeats to be anchored in the bilayer (left panel). In the absence of ATP, PS is translocated to the outer monolayer, enabling the dissociation of PS-binding repeats from the membrane and thereby making the lysine and arginine residues accessible for glycation.