Fig. 3. Distribution of WT-ACE and GPI-ACE in lipid rafts. CHO and SH-SY5Y cells expressing either WT-ACE or GPI-ACE were used to prepare lipid rafts by buoyant sucrose density-gradient centrifugation in the presence of Triton X-100 as described in Materials and Methods. The sucrose gradients were fractionated in 0.5 ml aliquots (0, insoluble pellet; 1, bottom of tube; 9, top of tube). (A) Distribution of total protein in sucrose gradient fractions. (B) Distribution of caveolin (CHO cells) and flotillin (SH-SY5Y cells) in sucrose gradient fractions. (C) Distribution of ACE activity in sucrose gradient fractions. The results are representative of triplicate experiments.