Tissue extracts are provided as Western blotting positive controls. Each vial contains 500 µg protein in 200 µl SDS-PAGE Western blotting solution. Recommended use is 50 µg (20 µl) per lane. Extracts should be stored at -20ºC, and repeated freezing and thawing should be minimized. Sample vial should be boiled once prior to use. Tissue extracts for immunoprecipitation are provided SDS-free. Each vial contains 2 mg protein in 800 μl SDS-free buffer. For subsequent WB use, resuspend pellet in 80-800 μl electrophoresis sample buffer (sc-24945, page 1170), boil once prior to use and load up to 20 μl per lane. Extracts should be stored at -80º C and repeated freezing and thawing should be avoided.