Question

Consider a microtubules that is in its shrinking phase. What would happen if the solution contained an analog of the GTP that cannot by hydrolyzed?

a. The ends of the microtubules would fray.
b. The microtubules would disassemble at a faster rate
c. The microtubule would undergo rescue and keep growing
d. The microtubule would continue shrinking
e. The microtubule would stop shrinking but wouldn't grow any further

Answer 1

A microtubule exposed to a non-hydrolyzable GTP analog would cease to shrink but also would not grow, since GTP hydrolysis typically drives these dynamics.

Step-by-step explanation:

If a microtubule that is in its shrinking phase were exposed to an analog of GTP that cannot be hydrolyzed, the microtubule would stop shrinking but wouldn't grow any further. This is because the hydrolysis of GTP to GDP is what normally powers both the growth and disassembly of microtubules. If the GTP analog is bound to the microtubule ends, it could potentially cap the ends and prevent the addition of new tubulin dimers, as well as protect it from disassembly.

This is because hydrolysis of GTP is a necessary step for microtubule disassembly. Without hydrolysis, the microtubule would not be able to disassemble and would continue to shrink.