The pre-OR residues 23–31 with a substitution of the proline residues by tryptophan or glycine residues form a PK-resistant structure in prion-infected N2a cells.

Abstract

<p>(A) Amino acid sequences of the pre-OR residues 23–31 in mutant proteins. Bold residues indicate substituted residues. (B) Western blotting of N2aC24L1-3 cells transfected with control pcDNA3.1(+) and expression vectors encoding each mutant protein using 3F4 anti-PrP antibodies. The cell lysates were treated with PK at 5 µg/ml. All of the mutant proteins were converted into PK-resistant isoforms in N2aC24L1-3 cells, and all of the mutant isoforms, moPrP(3F4)^ScΔ32–88, moPrP(3F4)^ScΔ32–88(2P2A), moPrP(3F4)^ScΔ32–88(2P2W) and moPrP(3F4)^ScΔ32–88(2P2G), gave rise to similar doublet non-glycosylated and mono-glycosylated bands. (C) Since substitution of proline residues into alanine, tryptophan or glycine residues disrupted the IBL-N epitope, the PK-resistant pre-OR residues in these mutant proteins failed to be visualized by IBL-N anti-PrP antibodies.</p