Effects of tubulin post-translational modification on microtubule bending rigidity and C-terminal tails

Microtubules are cytoskeletal filaments important for cellular processes including cell division, intracellular transport, and cellular movement. Tubulin is the heterodimeric building block of microtubules. Regulation of tubulin in the cell occurs primarily through post-translational modifications on the C-terminal tails. The intrinsically disordered C-terminal tails are involved in mediating binding interactions with tubulin and affecting larger scale microtubule dynamics. However, the means by which a small, flexible domain can have these large effects is unknown. We probe atomic level behavior of the C-terminal tails by NMR (Wall et al ACS Chem Bio 2016). In parallel, we used fluorescence microscopy to study microtubule thermal fluctuations, allowing us to determine the flexural rigidity of microtubules assembled from distinct tubulin pools.