In a neuron, proteins, and membranes are primarily synthesized in the cell body. These materials must be transported down the axon to the synaptic region using microtubules in an anterograde fashion. Such axonal transport is directed by
- Kinesin I
- Dynein and Kinesin I
Rephrasing the question:
What is the motor protein involved in anterograde axonal transport?
Kinesin is the motor protein that directs anterograde axonal transport (option 2).
In the cell, components like organelles and vesicles don’t just move randomly – it would be chaos! Proteins and organelles are transported along the ‘road system’ of the cells – a wide, dense network of microtubules.
This is also true in neurons, where most of the components used in the axon and the axon terminal are synthesized in the axon’s cell body and then transported in vesicles to the axon.
If microtubules are the ‘roads’ and vesicles are the ‘cargo,’ the ‘car engine’ that physically moves the vesicle along the road is the motor protein.
There are two motor proteins that work in axonal transport: dynein and kinesin.
- Dynein moves cargo from the cell body to the axon (anterograde movement).
- Kinesin moves cargo in the opposite direction – from the axon to the cell body (retrograde movement).
If you tend to confuse dynein and kinesin, you can use the mnemonic ADKR. This is just the words Anterograde, Dynein, Kinesin, and Retrograde in alphabetical order. Anterograde movement is powered by Dynein, and Kinesin directs Retrograde movement.