Polyamine Sharing between Tubulin Dimers Favours Microtubule Nucleation and Elongation via Facilitated Diffusion
Figure 11
Microtubule instability in the presence of polyamines.
To estimate the stability of microtubules, the time course of cold disassembly at 8°C of pre-assembled microtubules (35 µM tubulin) is reported in the presence or absence of 100 µM spermidine. The rate of disassembly is not affected by the presence of 100 µM polyamines whereas it is significantly reduced in the presence of 20 µM taxol, a well known stabilizing agent. These results are thus in agreement with our model since polyamines were not expected to significantly favor microtubule stability and thus should preserve microtubule dynamical instability.