Figure 3.
Expression and solubility of Δ23–31 PrP in transgenic mice. A, Equal volumes of protein from the brains of mice of the indicated genotypes were either untreated (lanes 1–5) or were treated with PNGase F (lanes 6–10) before blotting with anti-PrP antibody 6D11. Δ23–31 PrP is expressed at six times, four times, and one times in the three transgenic lines (lanes 3–5), compared with the level of WT PrP in a non-Tg mouse (lane 2). The asterisk denotes the endogenous C1 cleavage product. B, Brain lysates from Prn-p0/0 (lanes 1, 2), non-Tg (lanes 3, 4), Tg(Δ23–311×) (lanes 5, 6), and Tg(PG14) (lanes 7, 8) mice were ultracentrifuged to separate soluble (S) and insoluble (I) fractions. Like WT, Δ23–31 PrP is found only in the soluble fraction, while PG14 PrP, an aggregation-prone mutant, is partially insoluble.