NR AFOA
AU Horiuchi,M.; Caughey,B.W.
TI Specific binding of normal prion protein to the scrapie form via a localized domain initiates its conversion to the protease-resistant state
QU EMBO Journal 1999 Jun 15; 18(12): 3193-203
PT journal article
AB In the transmissible spongiform encephalopathies, normal prion protein (PrP-sen) is converted to a protease-resistant isoform, PrPres, by an apparent self-propagating activity of the latter. Here we describe new, more physiological cell-free systems for analyzing the initial binding and subsequent conversion reactions between PrP-sen and PrPres. These systems allowed the use of antibodies to map the sites of interaction between PrP-sen and PrPres. Binding of antibodies (alpha219-232) to hamster PrP-sen residues 219-232 inhibited the binding of PrP-sen to PrPres and the subsequent generation of PK-resistant PrP. However, antibodies to several other parts of PrP-sen did not inhibit. The alpha219-232 epitope itself was not required for PrPres binding; thus, inhibition by alpha219-232 was likely due to steric blocking of a binding site that is close to, but does not include the epitope in the folded PrP-sen structure. The selectivity of the binding reaction was tested by incubating PrPres with cell lysates or culture supernatants. Only PrP-sen was observed to bind PrPres. This highly selective binding to PrPres and the localized nature of the binding site on PrP-sen support the idea that PrP-sen serves as a critical ligand and/or receptor for PrPres in the course of PrPres propagation and pathogenesis in vivo.
MH Animal; Antibodies, Monoclonal/pharmacology; Binding Sites; Brain; Carboxypeptidases/metabolism; Endopeptidase K/metabolism; Endopeptidases/*metabolism; Epitopes/genetics/immunology; Glycosylation; Hamsters; Immunoglobulins, Fab/pharmacology; Mice; Models, Molecular; Molecular Weight; Potassium Chloride/pharmacology; PrPc Proteins/*chemistry/genetics/immunology/*metabolism; PrPsc Proteins/*chemistry/genetics/immunology/*metabolism; Protein Binding/drug effects; Protein Conformation/drug effects; Protein Isoforms/chemistry/genetics/immunology/metabolism; Sequence Deletion; Sodium Chloride/pharmacology
AD Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, NIAID, NIH, 903 S 4th Street, Hamilton, MT 59840, USA
SP englisch
PO England
EA pdf-Datei und HTML-Version