Title
Effect of metal ions on de novo aggregation of full-length prion protein
Author
Armin Giese, Johannes Levin, Uwe Bertsch, Hans Kretzschmar
Year
2004
Journal
Biochemical and Biophysical Research Communications
Abstract
It is well established that the prion protein (PrP) contains metal ion binding sites with specificity for copper. Changes in copper levels have been suggested to influence incubation time in experimental prion disease. Therefore, we studied the effect of heavy metal ions (Cu2+, Mn2+, Ni2+, Co2+, and Zn2+) in vitro in a model system that utilizes changes in the concentration of SDS to induce structural conversion and aggregation of recombinant PrP. To quantify and characterize PrP aggregates, we used fluorescently labelled PrP and cross-correlation analysis as well as scanning for intensely fluorescent targets in a confocal single molecule detection system. We found a specific strong pro-aggregatory effect of Mn2+ at low micromolar concentrations that could be blocked by nanomolar concentration of Cu2+. These findings suggest that metal ions such as copper and manganese may also affect PrP conversion in vivo.
Instrument
J-715
Keywords
Circular dichroism, Secondary structure, Ligand binding, Vesicle interactions, Biochemistry