Microtubules are protein intracellular structures resembling a tube made of protofilaments - long chains of tubulin protein. They are dynamically unstable, which is expressed in their constant presence in the phases of growth or shortening. Microtubules are involved in a variety of intracellular processes such as chromosome segregation and fission spindle formation. An effective method for studying the dynamics of microtubules is based on specific plus-tip- interacting proteins. They include a family of EB proteins (EB1, EB2, EB3) that autonomously recognize the plus-end of the microtubule. It is believed that they recognize the region rich in GTP-tubulins and responsible for the stability of the microtubule. In this paper, we decided to test this hypothesis by measuring the correlation between the size of the region recognized by the EB3 protein, the growth rate of the microtubule, and the growth time of the microtubule. The obtained data, especially in the context of comparison with the previously published in vitro experiments, allow us to better understand the nature of the change in the structure of the end of the microtubules during growth, and hence - bring us closer to understanding the mechanisms of dynamic instability of microtubules in living cells.
end-binding protein, microtubule, GTP-tubulin, dynamic instability
1. Alberts B., Bray D., Hopkin K. Essential Cell Biology third edition. Garlard science, 2013, vol. 731, p. 577.
2. Desai A., Mitchison T.J. Microtubule polymerization dynamics. Annual Review of Cell and Developmental Biology, 1997, vol. 13, pp. 83-117.
3. Mustyatsa V.V., Boyakhyan A.V, Ataullakhanov F.I., Gudimchuk. EB-familie Proteins and Microtubule Interaction Mechanisms. Biochemistry, 2017, vol. 82, pp. 1033-1046.
4. Maurer S.P. [et al.] GTPᵧS microtubule mimic the growing microtubule end structure recognized by end-binding proteins (EBs). PNAS, 2011, vol. 108, no. 10, pp. 3988-3993.
5. Bieling P. [et al.] Reconstitution of a microtubule plus-end tracking system in vitro. Nature, 2007, vol. 450, pp. 1102-1104.
6. Duelberg Christian, Thomas Surrey [et al.] The size of the EB cap determines instantaneous microtubule stability. eLIFE Research article, 2011, pp. 845-850.
