Expression of PrP mRNA is regulated by a fragment of MRP8 in human fibroblasts.

Prion protein (PrPc) is expressed in many tissues, both in human and animals. The scrapie isoform of PrPc has been shown to cause neurodegeneration. In other studies it has been demonstrated that overexpression of the PrP gene can result in nonneuronal tissue degradation. Little is known, however, about the normal function of PrPc and prion protein gene regulation. Using cultured periodontal ligament cells as an experimental model, we have demonstrated the stimulation of PrP mRNA expression by MRP8 (migration inhibitory factor-related protein). Additionally, we have shown that PDGF has an opposite effect acting as a suppresser. We propose that a correlation exists between PrPc mRNA expression and cell growth arrest and differentiation.