If the proteins that anchor acetylcholine-containing vesicles to the presynaptic membrane are damaged by botulism toxins, what effect will this have on the neuromuscular junction? A) Reuptake by the presynaptic membrane will be impaired. B) An action potential will not be able to open voltage-gated Ca²⁺ channels. C) Neurotransmitter will not be released into the synaptic cleft. D) Graded potentials will cause fusion of the vesicles with the cell membrane. E) Endocytosis of acetylcholinesterase will be impaired.

Question

Quizplus · Accepted Answer

The proteins that anchor acetylcholine-containing vesicles to the presynaptic membrane are called SNARE proteins. Botulism toxins damage these proteins, preventing the fusion of the vesicle membrane with the presynaptic membrane and the subsequent release of acetylcholine into the synaptic cleft. This will result in a decrease or cessation of neuromuscular transmission.

If the Proteins That Anchor Acetylcholine-Containing Vesicles to the Presynaptic