The mode of interaction of ataxin-3 Q36 (AT-3 Q36) with selected endogenous and exogenous metal ions, namely, Zn(2+), Cu(2+), Ni(2+), and Cd(2+), was examined. Metal-ion-induced structural changes of the protein were monitored by fluorescence as well as Fourier transform Raman spectroscopy. We found that the cations tested lead to a decrease in alpha-helical content and a concurrent increase in beta-sheet as well as undefined (beta-turn and random-coil) structures. The most evident effect was observed for copper and nickel cations. After titration with these cations, the AT3 Q36 secondary structure content (27% alpha-helices in the presence of either ion, 31 and 27% beta-sheets for Cu(2+) and Ni(2+), respectively) was similar to that observed for the aggregated form of the protein (27% alpha-helices, 36% beta-sheets). Using the 1-anilinonaphthalene-8-sulfonate hydrophobic fluorescence probe, we showed that the presence of the metal ions tested led to the formation of solvent-exposed hydrophobic patches of AT-3 Q36, and that such an effect decreased with increasing ionic radius.
|Citazione:||Stawoska, I., Weselucha-Birczynska, A., Regonesi, M.E., Riva, M., Tortora, P., & Stochel, G. (2009). Interaction of selected divalent metal ions with human ataxin-3 Q36. JBIC, 14, 1175-1185.|
|Tipo:||Articolo in rivista - Articolo scientifico|
|Carattere della pubblicazione:||Scientifica|
|Titolo:||Interaction of selected divalent metal ions with human ataxin-3 Q36|
|Autori:||Stawoska, I; Weselucha-Birczynska, A; Regonesi, ME; Riva, M; Tortora, P; Stochel, G|
|Data di pubblicazione:||lug-2009|
|Appare nelle tipologie:||01 - Articolo su rivista|