Phosphorylation and dephosphorylation of ribosomal protein S8 in starved Tetrahymena induced respectively by Na+ and K+ are accompanied by changes in intracellular pH which rises by about 0.8 pH units in cells starving in the presence of Na+ (phosphorylation of S8) and falls by a little more than one pH unit after subsequent addition of K+ (dephosphorylation of S8).
