In the second part of our talk with Dr. Chapman, we discuss the positive effects that botulinum toxin A, otherwise known as Botox, can have in combating a number of medical conditions. You will be surprised by how often Botox is used for non-cosmetic procedures. It is prescribed for carpal tunnel syndrome, stuttering, excess sweating, cervical dystonia, and other debilitating conditions. Botulinum toxin A works by cleaving proteins important for cell communication (as discussed in Part 1), but exactly how it acts through the nervous system is unclear. Dr. Chapman’s lab has discovered that neurotoxins such as botulinum toxin A can be absorbed by neurons through vesicles at one end of the cell and be transported backward to the neurons connected to it on the other end of the cell, affecting specific proteins in long chains of cells. His research provides important insights into the mechanism of how this useful toxin works.
This month, in our first two-part episode, we talk about vesicle fusion with Dr. Edwin Chapman, a Howard Hughes investigator at the University of Wisconsin-Madison. Vesicles are small balloons within the cell that can carry a variety of material ranging from proteins to cellular waste. They are also important message-delivery machines that allow neurons to communicate with each other. Through an extremely fast and complicated process known as synaptic vesicle exocytosis, vesicles containing neurotransmitters fuse with the neuron's membrane, releasing packets of neurotransmitter that will bind to the receptors on a neighboring neuron. This process is the basis of nearly all neuron-to-neuron communication and, consequently, underlies our thoughts and behavior. Using different techniques, Dr. Chapman hopes to provide a better understanding of the structure, function, and dynamics of this poorly understood but fundamental process.