Protein Domain : Alpha tubulin IPR002452

Type	Family
Description	Microtubules are polymers of tubulin, a dimer of two 55kDa subunits, designated alpha and beta [, ]. Within the microtubule lattice, α-βheterodimers associate in a head-to-tail fashion, giving rise to microtubule polarity. Fluorescent labelling studies have suggested that tubulin isoriented in microtubules with beta-tubulin toward the plus end [ ]. For maximal rate and extent of polymerisation into microtubules, tubulin requires GTP. Two molecules of GTP are bound at different sites, termed N and E. At the E (Exchangeable) site, GTP is hydrolysed during incorporation into the microtubule. Close to the E site is an invariant region rich in glycine residues, which is found in both chains and is thought to control access of the nucleotide to its binding site []. Most species, excepting simple eukaryotes, express a variety of closely related alpha- and beta-isotypes. A third family member, gamma tubulin, hasalso been identified in a number of species [ ].This entry represents alpha tubulin.
Short Name	Alpha_tubulin