tokens: Cells were lysed in buffer ( 20 mM HEPES pH 8 . 0 , 150 mM sodium chloride , 1 % Triton X - 100 , 2 mM EDTA ) with commercial protease ( Complete inhibitor cocktail , Roche , Pleasanton , CA , USA ) and phosphatase inhibitors ( 10 mM sodium fluoride , 2 mM sodium vanadate , 50 mu M ammonium molybdate ) .