Tubulin is the major building block of microtubules. This intracellular cylindrical filamentous structure is present in almost all eukaryotic cells. Globular tubulin subunits comprise the microtubule building block, with α/β-tubulin heterodimers forming the tubulin subunit common to all eukaryotic cells. γ-tubulin is required to nucleate polymerization of tubulin subunits to form microtubule polymers. Microtubules function as structural and mobile elements in mitosis, intracellular transport, flagellar movement and in the cytoskeleton. Tubulin is a heterodimer which consists of alpha tubulin and beta tubulin.
