Reagents: Protein extraction buffer (Camiolo buffer): 100 ml= (0.075M Potassium Acetate) 0.736g (0.3M) NaCl 1.753g (0.1M) L-arginine basic salt 1.742g (0.01M) EDTA-HCl 0.292g (0.25%) Triton X-100 250. ul up to 100 ml with dH20. pH 7.4. Then 0.2 um filter. 1. Freeze tissue in liquid nitrogen. 2. Rinse in PBS then mince. 3. Add 1 ml Camiolo extraction buffer per 100 mg of tissue. 4. Homogenize for 1 minute at 4'C. 5. Spin at 3,000. rpm/15 minutes/4'C. 6. Remove supernatant and save in another tube. 7. If necessary, dialize the supernatant against PBS with 50mM/L Tris-HCl pH 7.4.