XMAP215 proteins, such as Alp14 and XMAP215 (also known as CKAP5), increase microtubules dynamic polymerization rates by recruiting soluble alpha/beta-tubulin via their conserved TOG domains to polymerizing microtubule plus ends [, , ]. The TOG domain contains HEAT repeats, forming a oblong paddle-like structure. CKAP5 plays a major role in organizing spindle poles and acts as component of the TACC3/ch-TOG/clathrin complex proposed to contribute to stabilization of kinetochore fibres of the mitotic spindle by acting as inter-microtubule bridge [].Proteins in this family also includes the XMAP215 homologue, Stu2 from budding yeasts []and Alp14/Dis1 from fission yeasts [].
