Treadmilling as Carried Out by Microtubules Means

Question

Treadmilling as carried out by microtubules means:
A) ATP-hydrolysis-dependent movement over a plane.
B) ATP-dependent addition of dimmers to the plus end.
C) GTP-hydrolysis-dependent movement of α-tubulin over β-tubulin.
D) GTP-dependent addition to the plus end and removal at the minus end.
E) ATP-dependent "walking" along a surface in one place.

Accepted Answer

Treadmilling refers to the constant addition of subunits to the plus end of a microtubule while simultaneously removing subunits from the minus end. This process is GTP-dependent and does not involve ATP hydrolysis or addition of dimers to the plus end. Therefore, the correct choice is D which mentions the GTP-dependent addition to the plus end and removal at the minus end.