Professor Kenneth Kosik discusses the tau protein and its relationship to the neurofibrillary tangles found in Alzheimer's disease.
Tau is the protein that is formed in the neurofibrillary tangle, but tau is also a normal protein that we all have in our brain. It is mostly present in the axon of a neuron, the part that is projecting a long distance. In the axon, it is attached to the microtubules. You can think of tau as the ties along railroad tracks, with the railroad tracks being the microtubules and the ties being the tau protein. The purpose of this system of tau and microtubules is for moving cargo down these long distances, the long axons. Now, there has been some speculation that tau, because tau is a little complicated in all the different isoforms, the different forms it can have in the brain, that perhaps its regulation may indeed have some role in cognition. But we know very, very little about that at this time.