Internalization and mechanisms of action of clostridial toxins in neurons.

Botulinum toxins are metalloproteases that act inside nerve terminals and block neurotransinitter release via their activity directed specifically on SNARE proteins. This review summarizes data on botulinuin toxin modes of binding, sites of action, and biochemical activities. Their use in cell biology and neuroscience is considered, as well as their therapeutic utilization in human diseases characterized by hyperfunction of cholinergic terminals.