SH-SY5Y cells are trypsinised and lysed in 1% (v/v) Triton X 100, 50 mM Tris, pH 7.5, 750 mM NaCl, 5 mM EDTA, 4 units RQ1 RNase-free DNase (Promega), protease and phosphatase inhibitor mix (Halt) on ice for 15 minutes. The lysate is passed through a 23G needle and pelleted at 17,000 x g for 30 minutes at 4°C. Triton X 100 soluble fraction is collected and protein concentration measured using the BCA protein assay. Insoluble pellets are resuspended in 2% (w/v) SDS, 8 M urea, 10 mM Tris, pH 7.5, 4 units RQ1 RNase-free DNase, protease and phosphatase inhibitor mix and incubated for 15 minutes at room temperature. Debris is removed by centrifugation at 17,000 x g for 30 minutes at 4°C.