Potholes on the highway of the brain

A few weeks ago a neurobiologist was talking to me about a former student of his that was doing a project on microtubules. Microtubules are large structural proteins made up of tubulin subunits. They form a spiderweb-like network in cells, and proteins can be transported along it by another protein called kinesin. Molecular Biology of the Cell videos of microtubules. One example is the transport of neurotransmitters along the axons of neurons. The stability of neurons means that these proteins can stay in place for years. Consequently, there can be degradation of the protein over this time. This guy was studying how sugars reacted with the protein over long periods of time and how it affected the microtubules.

A press release for another project on Science Daily shows why this might be important.

Microtubules are hollow cylinders made up of polymers of the protein tubulin. Agents that break up, or depolymerize, microtubules disrupt the railway, stop the traffic and reduce the number of cargoes that get delivered to the neuronal surface. Defects in neuronal transport are involved in many neurological diseases.
-Eunice Yuen

The research indicated that the serotonin receptor signals the cell to depolymerise microtubules. This results in the glutamate receptor not being transported to the cell surface by these microtubules. As glutamate is involved in memory and learning the hypothesis is that dysfunction in the regulation of the glutamate receptor by serotonin could lead to mental disorders.