Sample preparation: 1. Place cells in a microcentrifuge tube and centrifuge to collect cell pellet. 2. Lyse the cell pellet with 100 μl lysis buffer on ice for 30 min (For 1 X 106 cells, lyse with 100 μl lysis buffer). 3. Centrifuge at 14,000 rpm (16,000 x g) for 10 min at 4°C. 4. Transfer the supernatant to a new tube and discard the pellet. Remove 20 μl supernatant and mix with 20 μl of 2x sample buffer. 5. Boil for 5 min. Cool at RT for 5 min. Microcentrifuge for 5 min. 6. Load up 40 μl of sample to each well of a 1.5 mm thick gel*. 7. Set gel running conditions according to the manufacturer’s instructions. Transfer the proteins to a nitrocellulose or PVDF membrane with variable power settings according to the manufacturer’s instructions. *Guidelines for choosing gel percentages are based on protein size to be detected: 4-5% gel, >200 kD; 7.5% gel, 120-200 kD; 8-10% gel, 40-120 kD; 13% gel, 15-40 kD; 15% gel, < 20 kD.