]]The western blot (sometimes called the protein immunoblot) is a widely used analytical technique used to detect specific proteins in the given sample of tissue homogenate or extract. It uses gel electrophoresis to separate native or denatured proteins by the length of the polypeptide (denaturing conditions) or by the 3-D structure of the protein (native/ non-denaturing conditions). The proteins are then transferred to a membrane, where they are probed (detected) using antibodies specific to the target protein. There are now many reagent companies that specialize in providing antibodies against tens of thousands of different proteins...