β-Tubulin belongs to the subfamily of tubulins. It has two β-sheets enclosed by α-helices. It also contains an N-terminal domain with the guanine nucleotide-binding region, an intermediate domain with taxol-binding site and a C-terminal domain, which has the binding surface for molecular motor proteins. Human β-tubulin consists of seven isoforms (βI (class I), βII (class II), βIII (class III), βIVa (class IVa), βIVb (class IVb), βV (class V), and βVI (class VI)). TUBB1 (tubulin beta class I) is located on human chromosome 6p21.33.(10)
Microtubules function as structural and mobile elements in mitosis, intracellular transport, flagellar movement and in the cytoskeleton. Mutation in the β-tubulin gene leads to various neuronal migration disorders such as lissencephaly, pachygyria and polymicrogyria malformations.
