A normal neuron regularly discharges a slew of molecules into the environment around it, relaying messages to neurons nearby and far. This process is the basis of learning, and now is also implicated in the development of cancer.
William Trimble, a U of T professor in biochemistry, studies neuroscience in his lab at the Hospital for Sick Children. Trimble was recently awarded a fellowship at the Royal Canadian Society for work exploring the neurological basis of learning. He has discovered a set of proteins that play a fundamental role in brain function, and may also regulate cell division throughout the body.
The process of learning, which happens on many different levels, is based on the efficacy of neuronal communication in the brain. Imagine a neuron as a Coca-Cola can. The can itself is a membrane that contains the soda to keep it carbonated. When you open it, bubbles float to the surface and release gas.
Neurons have vesicles, like the bubbles in pop, containing not gas but neurotransmitter molecules used to communicate with other neurons. Neurons “pop the bubbles” in order to send neurotransmitters across the space between neurons to deliver messages. This is called synaptic transmission.
Trimble and his team discovered a group of membrane-bound proteins, called SNARE proteins, that affect the release of neurotransmitters. He explained that since SNAREs help control the “popping” of neurotransmitter vesicles, they are part of the basis of neuron-to-neuron communication.
“The SNARE proteins cause the [neurotransmitter vesicle and the cell membrane] to melt together, resulting in…the discharge of the contents outside of the cell.”
In his research, Trimble stumbled upon a family of proteins, septins, that may regulate the function of SNAREs in synaptic communication, and also affect cell division.
“This was surprising since the septin proteins are found in neurons, which do not divide, and this suggested to us that…SNARE proteins may also be important in controlling cell division.”
Because these classes of proteins are involved not only in synaptic transmission in the brain, but in secretion in every cell in the body, and in cell division, Trimble’s research is branching out to examine whether these proteins play a role in cancer.
