NR AURJ
AU Kaimann,T.K.; Metzger,S.; Jansen,K.; Höltje,H.D.; Brandt,B.; Riesner,D.
TI Identification of potential interaction sites in alpha-helical dimers of the prion protein
QU TSE-Forum, 6. Kongress - Nationale TSE-Forschungsplattform, Greifswald 26.6.-28.6.2006, Poster: Struktur und molekulare Mechanismen MOL-07
PT Konferenz-Poster
AB
The basic event in the pathogenesis of prion diseases is the transition from the cellular, mainly alpha-helical prion protein (PrPc) to its pathogenic, (-sheet-rich isoform (PrPsc). The process underlying this conformational conversion remains largely unknown hence identification of intermediates plays a very important role. Several structural intermediates in the putative pathway from PrPc to PrPsc were established by systematic variation of solvent conditions at neutral pH. A non-covalent alpha-helical dimer of recPrP90-231 was found1 which displays a potential first step in the conversion process. In order to get a closer understanding of this initial conversion step, we focused on the structural properties of the alpha-helical dimer. We analysed contact sites within the dimer by chemical cross-linking using the zero-distance cross-linker EDC which mediates the transformation of salt bridges into peptide bonds. Determination of these contact sites within the complexes were carried out by tryptic digestion and identification of the resulting peptides by mass spectrometry. Three distinct contact sites were identified in the monomer and the dimer revealing preferential linkage of the N-terminus with the C-terminal part of helix 1 and two acidic residues in the hinge between helix 2 and 3 and in helix 3. Based on these results new structural models were generated using molecular dynamics simulations. Thereby a model for monomer structure was developed which provides information on the structure of amino acids 90-124 of PrP, which is not part of the globular structure as analyzed by NMR.
1 Jansen et al. (2001) Biological Chemistry, 382, 683-691
AD T.Kaimann, K.Jansen, D.Riesner, Institut für Physikalische Biologie, Heinrich-Heine-Universität, Düsseldorf, Germany, 40225; T.Kaimann, S.Metzger, K.Jansen, D.Riesner, Biologisch-Medizinisches Forschungszentrum, Düsseldorf, Germany, 40225; H.-D.Höltje, B.Brandt, Institut für Pharmazeutische und Medizinische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany, 40225
SP englisch
PO Deutschland
OR Tagungsband