NR ALGU
AU Supattapone,S.; Nguyen,H.O.B.; Muramoto,T.; Cohen,F.E.; DeArmond,S.J.; Prusiner,S.B.; Scott,M.R.D.
TI Affinity-tagged miniprion derivatives spontaneously adopt protease-resistant conformations
QU Journal of Virology 2000 Dec; 74(24): 11928-34
PT journal article
AB An abridged PrP molecule of 106 amino acids designated PrP106 can form infectious miniprions in transgenic (Tg) mice (29). Addition of six-histidine (His(6)) affinity tags to selective sites within PrP106 resulted unexpectedly in new PrP proteins that spontaneously adopted protease-resistant conformations when expressed in neuroblastoma cells and Tg mice. Acquisition of protease resistance depended on the length, charge, and placement of the affinity tag. Introduction of the disease-linked mutation E200K into the sequence of PrP106(140/6His) increased the recovery of protease-resistant PrP fivefold, whereas introduction of the mutations C213A and Delta214-220 did not affect the recovery of protease-resistant PrP. Treatment of cultured cells expressing affinity-tagged PrP106 mutants with polypropyleneimine dendrimer rendered these proteins sensitive to protease digestion in a manner similar to wild-type PrPsc. We conclude that certain affinity-tagged PrP106 proteins spontaneously fold into conformations partially resembling, yet distinct from, wild-type PrPsc. These proteins might be useful tools in the identification of new disease-causing mutations as well as for screening compounds for therapeutic efficacy.
MH Animal; Endopeptidases/*metabolism; Mice; Mice, Transgenic; Prions/*chemistry/*metabolism; *Protein Conformation; Structure-Activity Relationship; Support, Non-U.S. Gov't; Support, U.S. Gov't, P.H.S.
AD Institute for Neurodegenerative Diseases, University of California at San Francisco, San Francisco, California 94143, USA
SP englisch
PO USA