title: Folding pathways of prion and doppel.
abstract: The relevance of various residue positions for the stability and the folding characteristics of the prion protein in its normal cellular form are investigated by using molecular dynamics simulations of models exploiting the topology of the native state. These models allow for reproducing the experimentally validated two-state behavior of the normal prion isoform. Highly significant correlations are found between the most topologically relevant sites in our analysis and the single point mutations known to be associated with the arousal of the genetic forms of prion disease. Insight into the conformational change is provided by comparing the folding process of cellular prion and doppel that share a similar native state topology: the folding pathways of the former can be grouped in two main classes according to which tertiary structure contacts are formed first enroute to the native state. For the latter a single class of pathways leads to the native state again through a two-state process. Our results are consistent and supportive of the recent experimental findings that doppel lacks the scrapie isoform and that such remarkably different behavior involves residues in the region containing the two beta-strands and the intervening helix.
authors.affiliation: International School for Advanced Studies (S.I.S.S.A.) and INFM, via Beirut 2-4, 34014 Trieste, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Settanni
authors.forename: Trinh Xuan
authors.initials: TX
authors.lastname: Hoang
authors.forename: Cristian
authors.initials: C
authors.lastname: Micheletti
authors.forename: Amos
authors.initials: A
authors.lastname: Maritan
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D003198:Computer Simulation; D004735:Energy Transfer; D058851:GPI-Linked Proteins; D006801:Humans; D008958:Models, Molecular; D018621:PrPC Proteins / Q000737:chemistry; D018620:PrPSc Proteins / Q000737:chemistry; D011328:Prions / Q000737:chemistry* / Q000145:classification; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D020033:Protein Isoforms / Q000737:chemistry / Q000145:classification; D017434:Protein Structure, Tertiary; D013696:Temperature
chemical_list: D000596:Amino Acids; D058851:GPI-Linked Proteins; C501125:PRND protein, human; D018621:PrPC Proteins; D018620:PrPSc Proteins; D011328:Prions; D020033:Protein Isoforms