2D gel analysis of the anion-exchange HPLC cytosolic fractions. Proteins from each of the fractions resulting from the anion-exchange HPLC of the cytosolic sample were separated by 2D-PAGE according to molecular weight and pI point. The 40 mM fraction is the unbound protein fraction, while the subsequent fractions are proteins eluted by the increasing ammonium bicarbonate concentration step-gradients. Total proteins were detected by colloidal Coomassie stain while phosphoproteins were detected in the same gel using the ProQ Diamond phosphoprotein-specific stain. Relative molecular weights of protein standards are indicated in kDa.