NR AXRP
AU Ludewigs,H.; Sedlaczek,C.; Messow,D.; Pace,C.; Mitteregger,G.; Kretzschmar,H.A.; Nikles,D.; Vana,K.; Weiss,S.
TI In vitro- and in-vivo Downregulation of the LRP/LR level by LRP-specific siRNAs using a Lentivirus-based Delivery System
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Pathology and Pathogenesis P03.88
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases, which include Scrapie in sheep, BSE in cattle, CWD in cervides and CJD in humans. Prions, the causative agents of TSEs, are known to interact with the cellular prion protein (PrPc) by inducing conformational changes. The 37kDa/ 67kDa laminin receptor (LRP/ LR) acts as the cell surface receptor for both, PrPc (1) and the infectious prion protein (2,3). Additionally, heparan sulfate proteoglycans (HSPGs) were identified as co-factors/ co-receptors for PrPc (4). Furthermore, it has been shown that LRP/ LR is essential for PrPsc propagation in neuronal cells (5). The accumulation of PrPsc in scrapie-infected neuronal cells (N2aSc+) has been prevented by transfection with small interfering (si) RNAs specific for the LRP mRNA (5). These results demonstrate the necessity of the laminin receptor for the PrPsc propagation in cultured cells. Vector-based application of siRNAs circumvents the transient effect of downregulation of gene expression and allows persistent suppression and therefore analysis of lossof-
function-phenotypes that develop over longer periods of time. Transduction of recombinant HIV-based lentiviral vectors expressing siRNAs directed against defined regions of the LRP mRNA resulted in reduction of both, PrPres and LRP levels in scrapie-infected neuronal cells. To further enlighten the role of LRP/LR in prion diseases, injection of recombinant LRP-specific RNA interference (RNAi) lentiviral particles into mice using an intracerebral (i.c.) route was performed. Western blot analysis of the cortical brain area of mice intracerebrally injected with lentiviral vectors expressing siRNAs directed against the LRP mRNA showed a downregulation of the 67kDa LR. Subsequent prion inoculation in these mice will prove whether the knockdown of LRP/LR by RNAi might prolong the onset of or even prevent prion disease.
(1) Gauczynski et al. (2001) EMBO J. 20, 5863-5875; (2) Morel et al. (2005) Am. J. Path., 167, 1033-1042; (3) Gauczynski et al., (2006) J Infect. Dis., 194, 702-709; (4) Hundt et al. (2001) EMBO J. 20, 5876-86; (5) Leucht et al. (2003) EMBO rep 4, 290-295
AD H. Ludewigs, C. Sedlaczek, D. Messow, D. Nikles, K. Vana, S. Weiss, Gene Center, Institute of Biochemistry, Germany; C. Pace, G. Mitteregger, H.A. Kretzschmar, Center for Neuropathology and Prion Research, Germany
SP englisch
PO Schottland