What happened to kinesin movement after the addition of colchicine?

What happened to kinesin movement after the addition of colchicine?

• A. The kinesin can no longer move toward the axon terminus
• B. The kinesin movement remained unaffected
• C. The kinesin switched direction and moved toward the cell body
• D. The kinesin movement increased significantly

Answer: (A)

Kinesin is a motor protein that typically moves along microtubules in a directed manner, transporting cellular cargo towards the plus-end of the microtubule, which is oriented towards the axon terminus in neurons. Colchicine is known to disrupt microtubule formation by binding to tubulin, preventing polymerization and causing microtubules to depolymerize. When colchicine is added to a system where kinesin is functioning, the disruption of microtubules means that kinesin can no longer effectively attach to or travel along the microtubules. Without stable microtubules, the transport mechanism that kinesins rely on is compromised, leading to an inability to move towards the axon terminus. Thus, the addition of colchicine inhibits kinesin movement in this specific directional capacity, resulting in the first choice being the correct one.

Kinesin is a motor protein that typically moves along microtubules in a directed manner, transporting cellular cargo towards the plus-end of the microtubule, which is oriented towards the axon terminus in neurons. Colchicine is known to disrupt microtubule formation by binding to tubulin, preventing polymerization and causing microtubules to depolymerize.

When colchicine is added to a system where kinesin is functioning, the disruption of microtubules means that kinesin can no longer effectively attach to or travel along the microtubules. Without stable microtubules, the transport mechanism that kinesins rely on is compromised, leading to an inability to move towards the axon terminus. Thus, the addition of colchicine inhibits kinesin movement in this specific directional capacity, resulting in the first choice being the correct one.