NR APUY
AU Lawson,V.A.; Priola,S.A.; Meade-White,K.; Lawson,M.; Chesebro,B.
TI Flexible N-terminal region of prion protein influences conformation of protease-resistant prion protein isoforms associated with cross-species scrapie infection in vivo and in vitro
QU The Journal of Biological Chemistry 2004 Apr 2; 279(14): 13689-95
PT journal article
AB Transmissible spongiform encephalopathy (TSE) diseases are characterized by the accumulation in brain of an abnormal protease-resistant form of the host-encoded prion protein (PrP), PrPres. PrPres conformation differs among TSE agents derived from various sources, and these conformational differences are thought to influence the biological characteristics of these agents. In this study, we introduced deletions into the flexible N-terminal region of PrP (residues 34-124) and investigated the effect of this region on the conformation of PrPres generated in an in vitro cell-free conversion assay. PrP deleted from residues 34 to 99 generated 12-16-kDa protease-resistant bands with intact C termini but variable N termini. The variable N termini were the result of exposure of new protease cleavage sites in PrPres between residues 130 and 157, suggesting that these new cleavage sites were caused by alterations in the conformation of the PrPres generated. Similarly truncated 12-16-kDa PrP bands were also identified in brain homogenates from mice infected with mouse-passaged hamster scrapie as well as in the cell-free conversion assay using conditions that mimicked the hamster/mouse species barrier to infection. Thus, by its effects on PrPres conformation, the flexible N-terminal region of PrP seemed to influence TSE pathogenesis and cross-species TSE transmission.
MH Animals; Brain/metabolism; Cell-Free System; Endopeptidases/*metabolism; Hamsters; In Vitro; Isomerism; Mice; Peptide Fragments/chemistry/metabolism; Prions/*chemistry/*metabolism; Protein Structure, Tertiary; Scrapie/etiology/*metabolism; Species Specificity
AD Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, NIAID, National Institutes of Health, Hamilton, Montana 59840, USA
SP englisch
PO USA