Detection of GTP-Tubulin Conformation in Vivo Reveals a Role for GTP Remnants in Microtubule Rescues

摘要: Microtubules display dynamic instability, with alternating phases of growth and shrinkage separated by catastrophe rescue events. The guanosine triphosphate (GTP) cap at the growing end microtubules, whose presence is essential to prevent microtubule catastrophes in vitro, has been difficult observe vivo. We selected a recombinant antibody that specifically recognizes GTP-bound tubulin microtubules found GTP-tubulin was indeed present plus microtubules. Unexpectedly, remnants were also older parts which suggests GTP hydrolysis sometimes incomplete during polymerization. Observations living cells suggested these may be responsible for events recover from catastrophe.