Clinical sesh - prion proteins 09/09 Harris Flashcards
do PrP^sc proteins aggregate intracellularly or extracellularly?
extracellularly
what is one key difference in the clinical manifestation of prion diseases like CJD, vs other neurodegenerative diseases due to protein misfolding, like Alzheimer’s?
prion diseases like CJD present late-middle age and Out of the Blue, with Rapid neurodegeneration and onset of symptoms, vs more insidious onset in Alzheimer’s
name some symptoms of prion disease
dementia (loss of cognitive ability) loss of motor control -ataxia -tremor -myoclonus
what is the incubation period of prion disease
years, decades
how long do symptoms of prion disease persist?
6 months - 5 years, death
T/F prion diseases are fatal
true
Kuru is what kind of desease
prion disease in cannibals
“kuru” = “shaking”
how was the prion disease Kuru transmitted?
ritual cannibalism in New Guinea tribes
why were women and children primarily affected by Kuru?
women and children traditionally ate the central nervous system, where pathological prion proteins were located
Scrapie is what kind of disease
prion disease in sheep
what is the penetrance of familial prion disease?
100%
if you inherit the gene, you will suffer
explain the prion hypothesis
diseases like scrapie, mad cow, cjd, kuru are caused by modified cellular proteins that are infection in the absence of nucleic acids (DNA or RNA)
i.e. proteinaceous infection, not viral, not bacterial
why did the prion hypothesis deviate from traditional knowledge at the time?
it volated the central dogma that DNA –> RNA –> protein… proteins were creating other infectious proteins without DNA or RNA
what is PrPc and where is it usually found
cell surface glycoprotein usually found in neurons and glial cells
what is the normal function of PrPsc
no normal function, exists in diseased nervous system only (however PrPc is a cell surface glycoprotein usually found in neurons and glial cells)
