title: Inhibition of prion amplification by expression of dominant inhibitory mutants--a systematic insertion mutagenesis study.
abstract: Until now it is still not clear which structural elements of the prion protein (PrP) are involved in its conversion process. Characterisation of these essential regions would help to understand the conversion process itself and might help to develop specific therapeutic approaches to inhibit PrP(res) formation by dominant inhibitory mutations. To address this important question 33 evenly spaced insertion mutants were generated spanning the entire sequence of the murine 3F4-tagged PrP. The mutants were expressed by retroviral transduction in three different scrapie infected cell lines (ScN2a; SMB[RC040]; SMB[22F]). The convertibility was affected not only by introducing the insertion in the putatively refolded region (aa100-170), but also in the C-terminus of PrP (up to aa214). Moreover, dominant inhibitory effects on conversion were observed for PrP-mutants at four distinguished regions (aa100-112; aa130-154; aa166-172, aa196-200). Computer based structural analysis revealed that these segments were organized in two structurally clearly separated regions supporting the idea that they could function as protein-protein interaction sites which are necessary during seed formation.
authors.affiliation: Institute for Novel and Emerging Infectious Diseases at the Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany. martin.groschup@fli.bund.de
authors.forename: Markus
authors.initials: M
authors.lastname: Geissen
authors.forename: Harriet
authors.initials: H
authors.lastname: Mella
authors.forename: Armin
authors.initials: A
authors.lastname: Saalmüller
authors.forename: Martin
authors.initials: M
authors.lastname: Eiden
authors.forename: Juliane
authors.initials: J
authors.lastname: Proft
authors.forename: Eberhard
authors.initials: E
authors.lastname: Pfaff
authors.forename: Hermann M
authors.initials: HM
authors.lastname: Schätzl
authors.forename: Martin H
authors.initials: MH
authors.lastname: Groschup
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D005786:Gene Expression Regulation; D006031:Glycosylation; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D018620:PrPSc Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054730:Protein Interaction Domains and Motifs; D020033:Protein Isoforms; D017434:Protein Structure, Tertiary; D021381:Protein Transport
chemical_list: D018620:PrPSc Proteins; D020033:Protein Isoforms