If is it in the CNS why wouldnt it be in the PNS???
Prion diseases are associated with the build up in the brain (and some other organs) of an abnormal or rogue form of a naturally occurring cellular protein, known as the prion protein. The rogue protein results from a change in shape of the normal prion protein. Once formed in the body these rogue proteins recruit and convert more of the normal prion protein into the abnormal form, setting off a kind of chain reaction which leads to a progressive accumulation of the rogue protein. In the normal course of events, once they have served their purpose, prion proteins are broken down by enzymes in the body. The abnormal prions however are more resistant to this process; so they accumulate and cause damage in the brain, which interferes with normal brain functioning. All forms of the disease are thought to be associated with an incubation period. This is a clinically ‘silent phase’ during which replication of the rogue protein is thought to be taking place.
The function of the normal form of the protein remains unclear, though it is thought they may possibly play a role in the transport of messages between specific brain cells (synaptic transmission.)