Tubulin, beta 3 class III, also known as TUBB3, is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha-chain. TUBB3 plays a critical role in proper axon guidance and mantainance. Recombinant human TUBB3 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.