Radioruthenium uptake by the erythrocyte membrane proteins

106Ru binding to erythrocyte membrane proteins was studied in suspensions of washed human erythrocytes. 106Ru was present in the form of RuCl3 solution adjusted by titration with 0.1 N NaOH to pH 3.7. After 1 hour incubation of 106Ru with the erythrocytes at 37 0C, the ghosts were prepared by hypotonic hemolysis and the membrane proteins were separated by SDS polyacrylamide gel electrophoresis. In general, radioactivity was associated with the stained protein bands proportionally according to the densitometric pattern of the stained gel. It means that the highest relative count rate was measured in the gel fractions corresponding to the integral membrane glycoproteins (band 3 and glycophorin) and spectrin. No specific interaction with any protein constituent of the erythrocyte membrane was observed. (author)