Demyelinating polyneuropathy in goats lacking prion protein.

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• The cellular prion protein (PrP^C) is encoded by the Prnp gene.
• Studies in mice suggest PrP^C is vital for peripheral nerve myelin maintenance.
• A naturally occurring mutation in goats provides a non-transgenic model to study PrP^C function.

Purpose of the Study:

• To investigate the role of PrP^C in peripheral nerve myelin maintenance using a goat model.
• To determine if the absence of PrP^C leads to demyelination in a non-transgenic mammal.

Main Methods:

• Utilized goats with a naturally occurring nonsense mutation leading to a lack of PrP^C.
• Examined teased nerve fiber preparations.
• Analyzed peripheral nerve lipid composition in young and adult goats with and without PrP^C.

Main Results:

• Goats lacking PrP^C exhibited a demyelinating pathology in peripheral nerves.
• Affected nerves showed immune cell invasion (macrophages, T cells), vacuolated fibers, shrunken axons, and onion bulb formations.
• Peripheral nerve lipid composition differed significantly in adult goats without PrP^C, indicating progressive neuropathy.

Conclusions:

• Loss of PrP^C function causes a subclinical demyelinating polyneuropathy in a non-transgenic mammal.
• This study confirms the essential role of PrP^C in peripheral nerve myelin maintenance.
• The findings highlight PrP^C as a critical factor for long-term nerve health.