Dynamic instability

The cycle of microtubule polymerisation and depolymerisation is essential for the dynamic instability of microtubules observed in vivo. The rate of microtubule polymerisation, pausing, depolymerisation and rescue can be modulated by microtubule associated proteins (MAPs) and motors. Steps: 1. Rapid growth with GTP-capped end 2. Accidental loss of GTP cap 3. Rapid shrinkage 4. regain of GTP cap 5. etc