The first bacterial cytoskeletal protein FtsZ, a bacterial tubulin homologue, was found in 1992. After these 25 years of research, more bacterial cytoskeletal proteins were identified. The prokaryotic tubulin homologues include FtsZ, CetZ, TubZ and BtubA/B. X-ray crystal structures have confirmed that they have similar structures. In the presence of GTP, they assemble into different polymers, such as single filaments, double helix filaments or bundles. These filaments conduct many different important functions including cell division, controlling cell shape and plasmid partition.