Disease-associated mutations in the prion protein impair laminin-induced process outgrowth and survival

In CF10 cells that express mutated PrPC, Mitomycin C also inhibited cell growth (Fig. 6A) without affecting viability measured by trypan blue exclusion (Fig. 6B). Cell death induced by Mitomycin C 48 h after treatment was also evaluated by activation of caspase 3. Contrary to the positive control, staurosporin,  Mytomycin C did not induce cell death (Fig. 6C). These cells, together with non-transfected and wild-type PrPC-expressing CF10 cells (PrP3F4), were also evaluated for process outgrowth mediated by the Ln γ1 peptide. Figure 6E shows representative images of the morphology of these cells following Ln γ1 peptide  treatment  and immunolabeling with microtubule-associated protein 2 (MAP2). CF10 cells transfected with wild- type PrPC (PrP3F4) presented long cytoplasmic processes (arrows in first panel; upper left). Remarkably, the addition of the Ln γ1 peptide was unable to promote process outgrowth in CF10 cells expressing mutated PrPC molecules (quantification in Fig. 6D). These results indicate that CF10 cells lacking PrPC, or expressing mutated PrPC, are unable to extend cytoplasmic process upon Ln γ1 peptide treatment.

 

PrPC mutations impaired protection against cell death triggered by Ln γ1 peptide

PrPC  has…