Question

"We now know that the core molecular cause of Parkinson's disease and Huntington's disease resembles that of several other neurodegenerative disorders: Creutzfeld-Jakob disease, Alzheimer's disease, frontotemporal dementia, chronic traumatic encephalopathy (the progressive brain degeneration seen in people who have suffered repeated concussions), and the genetic form of amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease). All of these diseases result from abnormally folded proteins that form clumps in the brain, becoming toxic and eventually killing neurons.

In 1982, Stanley Pruisner of the University of California, San Fransisco, announced a remarkable discovery: an infectious abnormally folded protein is involved in Creutzfeld-Jakob disease, a rare degenerative brain disorder, Pruisner called this protein a prion."

Discuss how prions are formed, how they are infectious and how they kill neurons. At what 3 points in prion formation may potential drugs be effective in slowing brain degeneration?

Answer 1

The Prion Protein (PrP) belongs to the class of amyloid-forming proteins.

A prion is a type of protein that can trigger normal proteins in the brain to fold abnormally.

It is not known what causes the normal protein to misfold, but the abnormal three-dimensional structure is suspected of conferring infectious properties, collapsing nearby protein molecules into the same shape.

The word prion derives from "proteinaceous infectious particle"

Prion diseases occur when normal prion protein, found on the surface of many cells, becomes abnormal and clump in the brain, causing brain damage.

This abnormal accumulation of protein in the brain can cause memory impairment, personality changes, and difficulties with movement. Experts still don't know a lot about prion diseases, but unfortunately, these disorders are generally fatal.

How they kill neurones?

Brain-wasting proteins called prions kill neurons by shortening the dendritic spines that the cells use to transmit signals to each other.