Tissue lysate was prepared by homogenization in ice-cold modified RIPA Lysis Buffer with cocktail of protease inhibitors (Sigma). Cell debris was removed by centrifugation. Protein concentration was determined with Bradford assay (Bio-Rad protein assay, Microplate Standard assay). The lysate was adjusted to 5 mg/ml.
Use it directly for immuno-precipitation, or heat lysate with SDS gel loading buffer to 95°C for 5 minutes followed by rapid cooling for western blot application. If dissociating conditions are required, add reducing agent prior to heating.
In modified RIPA Lysis Buffer.
Store at -80°C. Aliquot to avoid repeated freezing and thawing.