Transcript Prions (this will probably be covered in lab on Friday)

“Scrapie”
“mad cow disease”
Prions
Nobel Prize 1997
Dr. Stanley Prusiner
Prions
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What are prions?
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What is the evidence for prions?
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Notable prion diseases
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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
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Can have very long incubation periods
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Present at approximately 50-60 years of age
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Invariably fatal in a matter of months
Prions have been linked to various related neurological diseases
Dr. Carleton Gajdusek
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Kuru: human
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Fatal Familial Insomnia: human
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Creutzfeldt-Jakob disease (human)
Brain tissue
Kuru
New Guinea
Prion Diseases in Animals
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Scrapie (goats, sheep)
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BSE or Bovine Spongiform Encephalopathy (cattle)
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Chronic Wasting Disease (deer, elk)
Creutzfeld Jakob
Scrapie
BSE
KURU
Normal Mammalian Cells Have a:
PrP gene
PrP protein
Perhaps functions in cell communication
Prion diseases happen as a result of modified PrP
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”.
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Proteins that replicate
PrP
Rod shape
structures
Various strains of prions
Prion diseases may present as:

Genetic
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Sporadic
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Infectious
PrP
And many other manners of contact
with infected tissue.
Treatment
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Currently no available treatment
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Future drugs may target
 Binding
of modified PrP to wt Prp
Onto HIV/AIDS