Post‐translational modifications of tubulin, such as the removal of the C‐terminal tyrosine of α‐tubulin, have long been proposed to influence the ability of microtubule motors to walk along the microtubule surface. This hypothesis has now been tested for cytoplasmic dynein‐1 (dynein), revealing that active dynein–dynactin–adaptor complexes prefer to start moving on tyrosinated microtubules. This choice is governed by the p150 subunit of dynactin. Once moving, however, dynein is not choosy about whether the microtubule is tyrosinated or not.
See also: RJ McKenney et al
Microtubules (MTs) provide the tracks along which the dynein and kinesin families of motors move. Together, they generate the myriad complex movements that are needed for cells to grow, divide, move and communicate. MTs are polymers of alpha and beta tubulin dimers (Fig 1), which are very highly conserved eukaryotic proteins. In the cell, MTs vary greatly in their longevity, with some lasting only minutes, while others persist for many hours (Yu et al, 2015). MTs are particularly stable within axons, cilia and flagella. Such stable MTs accumulate a range of post‐translational modifications (PTMs), including acetylation, polyamination, polyglutamylation, polyglycylation and the removal of C‐terminal tyrosine from α‐tubulin (Janke, 2014; Yu et al, 2015). However, many cultured cell types, such as HeLa, have mostly unmodified tubulin.
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