L4 Prion Flashcards
(44 cards)
Define prion Diseases.
Prion diseases occur when proteins normally in the body misfold and cause illness. The misfolding leads to brain damage and other symptoms.
What 2 diseases does prion protein have significance in?
Cancer
Alzheimers
What does GPI do?
Facilitate attachment of prion on cell membrane
Why are the multiple bands on western blots of PrPc?
cleavages & glycosylation
Why is beta cleavage unusual?
Beta cleavage is unusual as not a traditional protease that does this - oxidative stress clips this protein off
What are genetic human prion diseases?
CJD, GSS due to PRNP mutations
What are infectious prion human diseases?
Kuru
Iatrogenic CJD
Variant CJD
Are sporadic CJD infectious?
Yes
What was Kuru associated with?
Ritualistic cannibalism
What is scrapie?
Disease of sheep
What is BSE?
Disease of cattle
What is CWD?
Disease of deer/elk
How does the prion protein change in disease?
Increase in beta sheet content & protein is resistant to proteases
not soluble in non-ionic detergents
resistant to destruction by standard decontamination processes
What are 3 forms of transmission/
Molecule-to-molecules
Host-to-host transmission
cell-to-cell transmission
How does the disease pass from cell to cell?
Use tunneling nanotubules
What mutations are found in the C & N terminus?
C = point mutations
N = insertions
What protein is AD related to?
APP
What pathway is bad processing of Ab?
Amyloidgenic pathway
beta-secretase
What pathway is good processing of Ab?
Alpha secretase
What are 3 steps to AB oligomers neuropathology?
- ab production
- assembley into oligomers
- Ab interaction with neuron receptors
What is PrPc a regulator of?
AB production
What do AB oligomers bind to?
N-terminus of membrane bound PrPc in AD brains
What does PrPc/sc expression enhance?
AB plaque production
Does PrPSc also bind to AB?
yes
