Joel

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UNSW ANATOMY 2004
Prion Proteins
Andy Clare, Brian S. Borbe, David V. Le, Joel A.
Jukes, Mitchell Clare. ANAT3231 Cell Biology
Andy Prions and their role in memoery

Introduction to Prions The word Prions
(pronounced Pree-Ons) is short for proteinaceous
infectious particles and has been found to be
small mutated protein molecules related to
infectious diseases like that of mad cow and
scrapies in animals including kuru and
Creutzfeldt-Jakob disease in humans. The term
prions itself was first coined by Stanley B.
Prusiner an American scientist whom for two
decades struggled to convince his peers that
certain proteins were possibly responsible for
various unusual brain diseases, which in medical
terms is called spongiform encephalopathies.
Prusiner was later in 1997 presented with the
Nobel peace prize in medicine. Prion proteins
are as stated in their name protein molecules and
as such have no genetic information. Instead the
proteins are made up of several amino acids,
which due to a defect subsequently direct the
prion protein to fold in a dysfunctional manner.
This abnormal folding occurs when the normal PrPc
protein mutates to form an abnormal PrPsc
protein.
Mitchell
Prions How they Work Each and every protein
when activated folds in a specific way, prion
proteins are no different. When an abnormal
PrPsc protein folds, it folds in an unusual way
which adversely affects the cell (neuronal
cells). The PrPsc protein then attaches to other
healthy PrPc proteins, building a template that
changes the normal conformation of the healthy
prion protein to that of the disease causing
proteins. This continual cycle occurs until the
neuronal cell dies and disperses the infectious
prion protein to Surrounding brain cells, this
process occurs until approximately all brain
cells are affected.
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Brian
Joel
Prion Cycle???
Reference