Why Tau


Tau is a protein found in neurons, where it works to stabilize the shape and function of the cell. As part of normal function, proteins in the body fold, unfold and refold into different shapes in order to perform specific functions, and when they are no longer needed, they are broken down and recycled by the cell. In many neurodegenerative diseases, the normal folding and unfolding stop, and the misfolded protein begins to accumulate in the neuron preventing normal cellular function. Misfolded tau is found in progressive supranuclear palsy, frontotemporal dementia with parkinsonism, and Alzheimer’s disease.

Proteins are complex molecules that are the building blocks of the cells in our body and the processes that these cells perform. Tau is a protein that helps form the shape of neurons and allows vital nutrients and proteins to move along the cell. It stabilizes the microtubules within the long axons of neurons. Microtubules act like railroad tracks inside the neuron connecting the cell body (and incoming signals) to the dendrites and synapses. If the microtubules become dysfunctional because tau isn’t doing its job, the neuron will eventually die.

In 1997, Dr. Stanley Prusiner won the Nobel Prize in Physiology or Medicine "for his discovery of prions—a new biological principle of infection." Until then, no one believed that proteins could cause or spread infection. Normal proteins fold and unfold constantly, but in neurodegenerative conditions like Alzheimer’s disease, frontotemporal dementia and progressive supranuclear palsy, the protein misfolds into a toxic form that loses its normal function, aggregates, and then spreads to adjacent cells. We now know many neurodegenerative diseases are caused by the misfolding of proteins into these toxic, infectious forms. Diseases caused by misfolded tau are called tauopathies. Pure tauopathies (diseases that only involve abnormal tau) include Pick’s disease, progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and argyrophilic grain disease. A combination of abnormal tau and other proteins also plays a destructive role in Alzheimer’s disease, chronic traumatic encephalopathy (associated with head trauma), Niemann-Pick-C, Guam-ALS-Parkinson’s-dementia, aluminum toxicity and post-encephalitic Parkinson’s disease. The Tau Consortium is working to cure pure tauopathies. If successful, these therapies have potential to treat secondary tauopathies, including Alzheimer’s disease and chronic traumatic encephalopathy.