Botulinum toxins binds to receptors present at the axon terminal in order to enter the neuron. What vesicular transport process do you think is involved in the toxin entering the nueron?

In the case of the Botulinum toxins, the vesicular transport process that's involved is the receptor mediator endocytosis. The Botulinum toxin binds to a Botulinum toxin receptor by its heavy chain. Once endocytosed, a light chain of the toxin is released into the axon terminal where it will have its action impeding acetylcholine to be released.