NR AOZT
AU Terry,L.A.; Barnicle,D.A.; Morais,A.; Jackman,R.
TI Differential proteolysis and PrPsc conformers
QU International Conference - Prion diseases: from basic research to intervention concepts - TSE-Forum, 08.10.-10.10.2003, Gasteig, München - Poster session - DG-32
PT Konferenz-Poster
AB The abnormal isoform of the prion protein (PrPsc) has been conventionally characterised by its relative resistance to degradation by proteolytic enzymes. Recent evidence has indicated that strain diversity of prion diseases may be identified by differences in proteolytic sensitivity of PrPsc. The aim of this study is to determine whether characteristics of resistance to degradation may be exploited in order to identify prion strains. Using SDS-PAGE and Western blot we have compared the patterns of hydrolysis of PrPsc derived from brain homogenates of cattle infected with BSE and sheep infected with scrapie. We have demonstrated that the susceptibility of the protease 'resistant' core, to partial and complete digestion over extended periods of time (up to 48 hours), is dependent on buffer composition. These differences in susceptibility were neither species nor strain specific. Kinetics studies to ascertain the extent of N-terminus digestion were performed using antibodies specific to distinct regions of the PrP molecule. In this case, the rate of digestion of the N-terminus was clearly species specific and partially dependent on buffer composition. In addition, the rates of digestion suggest heterogeneity of molecular forms within a sample. These studies have demonstrated patterns of proteolytic digestion of PrPsc that may facilitate the definition of subtle variation in PrPsc conformation and enable differential identification of prion strains.
AD Linda A. Terry, Donna Barnicle, Ana Morais, Roy Jackman, TSE molecular biology department, VLA, UK
SP englisch
PO Deutschland