Prions “Scrapie” “mad cow disease” Nobel Prize 1997 Dr. Stanley Prusiner

Prions What are prions? What is the evidence for prions? Notable prion diseases Modes of obtaining “prion” diseases

Infectious pathogens resistant to:

From: S. Prusiner, 1998: Nobel Laureate for Prions Once the requirement of protein for infectivity was established, I thought that it was appropriate to give the infectious pathogen of scrapie a provisional name that would distinguish it from both viruses and viroids. After some contemplation, I suggested the term "prion," derived from proteinaceous and infectious (58). At that time, I defined prions as proteinaceous infectious particles that resist inactivation by procedures that modify nucleic acids. I never imagined the irate reaction of some scientists to the word "prion"   it was truly remarkable!

Prion Diseases Can have very long incubation periods Present at approximately 50-60 years of age Invariably fatal in a matter of months

Prions have been linked to various related neurological diseases Dr. Carleton Gajdusek Kuru: human Fatal Familial Insomnia: human Creutzfeldt-Jakob disease (human) Kuru New Guinea Brain tissue

Prion Diseases in Animals Scrapie (goats, sheep) BSE or Bovine Spongiform Encephalopathy (cattle) Chronic Wasting Disease (deer, elk)

Creutzfeld Jakob Scrapie BSE KURU

Normal Mammalian Cells Have a: PrP gene Perhaps functions in cell communication PrP protein

Prion diseases happen as a result of modified PrP http://gslc.genetics.utah.edu/features/prions/

The modified PrP forms “rods” and destroys nerve cells. “Holes in the tissues are where the Nerve cells have been destroyed”.

Proteins that replicate PrP Rod shape structures

Various strains of prions

Prion diseases may present as: Genetic Sporadic Infectious PrP And many other manners of contact with infected tissue.

Treatment Currently no available treatment Future drugs may target Binding of modified PrP to wt Prp

Onto HIV/AIDS