NR AWMM
AU Rigter,A.; Langeveld,J.P.M.; Timmer-Parohi,D.; Priem,J.; Bossers,A.
TI Probing for PrPc amino acid residues involved in PrP-PrP interactions
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions CE-42
PT Konferenz-Poster
AB To understand the underlying mechanism of prion diseases the interaction between PrPc and PrPsc is being investigated. We previously demonstrated that disease related polymorphisms do not modulate the initial binding of PrPc to PrPsc and that a subsequent step in the conversion process should be responsible for determining differential conversion efficiencies. Because it is not clear whether the primary binding site of PrPc to PrPsc is also the site where the actual conversion is initiated (nucleation site) or whether a separate nucleation site is present in PrP, residues involved in protein-protein interaction need to be determined. This may reveal the site(s) responsible for binding and/or initiation of conversion. In order to determine which residues are capable of interacting with PrPc an synthetic solid-phase array containing a complete set of overlapping 15-mer PrP-peptides was probed with wild type (ARQ) sheep PrPc fused to maltose binding protein (MBP-PrPc) and bound MBP-PrPc was detected by indirect ELISA for MBP. The results revealed two distinctive high binding areas the first covering the ovine PrP amino acid residues 30-108, comprising the N-terminal octarepeats, the second covering residues 128-197, encompassing the disease associated polymorphisms in sheep PrP. Based on these results several antibodies and peptides were tested for their capacity to block the binding of MBP-PrPc to the peptides. Parallel to that, the peptides are currently under investigation for their capacity to block PrPres formation in our in vitro conversion assay. Furthermore, binding of MBP-PrPc to the peptides has spurred investigation into direct detection of PrPc and/or PrPsc in brain homogenates.
AD A. Rigter, J. Langeveld, J. Priem, A. Bossers: Central Institute for Animal Disease Control (CIDC-Lelystad), the Netherlands; D. Timmer-Parohi: Pepscan Systems BV, the Netherlands. E-mail: alan.rigter@wur.nl
SP englisch
PO Italien