Heterogeneous PrPC metabolism in skeletal muscle cells

Recent reports have shown that prions, the causative agent of transmissible spongiform encephalopathies, accumulate in the skeletal muscle of diseased animals and man. In an attempt to characterise in this tissue the prion protein (PrPC), whose conformational rearrangement governs the generation of prions, we have analysed the protein in primary cultured murine myocytes and in different skeletal muscle types. Our results indicate that the expression and cellular processing of PrPC change during myogenesis, and in muscle fibres with different contractile properties. These findings imply a potential role for PrPC in the skeletal muscle physiology, but may also explain the different capability of muscles to sustain prion replication.