Tubulin is one of several members of a small family of globular proteins. The most common members of the tubulin family are α-tubulin and β-tubulin, the proteins that make up microtubules. Microtubules are obligate proteinaceous elements found in nearly all eukaryotic cells. The availability of monoclonal antibodies to α-tubulin uses as a common housekeeping protein and serves as a specific and useful tool in studying proper interpretation of western blots.