Mouse PrP There is a core of 2 long helices in a hairpin. Two short β-strands are antiparallel, and are connected by a short helix. This region seems to undergo conformational changes when the PrP aggregates, in its pathological form. Riek, R., Hornemann, S., Wider, G., Billeter, M., Glockshuber, R., Wuthrich, K.: NMR structure of the mouse prion protein domain PrP(121-231). Nature 382 pp. 180 (1996) (PubMed) 1ag2 (PDB)