S [47,59,60].methylsulfonyl fluoride, with the addition of 0?0 mM SDS as required.

S [47,59,60].methylsulfonyl fluoride, with the addition of 0?0 mM SDS as required. Samples were incubated without shaking at 37uC in airtight containers to prevent evaporation.Thioflavin T FluorescenceThioT fluorescence measurements were recorded on a Gemini platereader, using the buffering conditions described previously with the addition of 30 mM ThT and 0?0 mM SDS. Excitation and emission wavelengths of 430 nm and 480 nm with a cut off filter of 455 nm were used, and both excitation and emission were read from the underneath of a black clear bottom plate. All reactions were completed at 37uC with no shaking.117793 site Membrane Filter Trap AssayAliquots containing 7.4 mg of protein were taken from the fibrillogenesis reaction, diluted 1:1 with a 4 (w/v) SDS/100 mM DTT solution and then boiled for 5 min at 100uC. 200 mL of 2 (w/v) SDS was then added to each of the samples, and 5 mg of protein were filtered through a 0.2 mm cellulose acetate membrane (Schleicher and Schuell) using a Bio-Rad Bio-Dot SF microfiltration unit. The membrane was then washed twice by filtering 200 mL of 0.1 (w/v) SDS, and blotted with a hexahistidine (His6) antibody (Serotec). Densitometry was completed using the program Phoretix 1D Quantifier.Materials and Methods MaterialsPhenylmethylsulfonyl fluoride, b-mercaptoethanol and thioT were all obtained from Sigma.Transmission Electron MicroscopyTEM images were obtained using a Hitatchi H7500 transmission electron microscope with an accelerating voltage of 80 kV. The samples were adsorbed onto a carbon-coated grid and stained with 1 (w/v) uranyl acetate.Expression and Purification of Ataxin-3 variantsAll ataxin-3 variants were expressed and purified as previously described 1315463 [61,62], and the proteins were stored at 280uC. Following purification the deubiquitinating activity of the proteins was measured [10] and before use all were analyzed using gel filtration to ensure that no multimeric species were present.Protein-lipid OverlayThe protein-lipid overlay assay was performed using fibrillar protein stopped at various timepoints. The protein was incubated with the phospholipids (PIP Strips, Molecular Title Loaded From File Probes) overnight at 4uC. Each lipid dot contained 100 pmol of phospholipids. The membrane was then blotted using His6 primary antibody (Serotec) and peroxidase-conjugated secondary antibody as described [64].Circular DichroismFar-UV CD spectra were measured on a Jasco-810 spectropolarimeter at 37uC using a path length of 0.1 mm. Scans of monomeric protein in the presence of different concentrations of SDS were carried out. For time course assays, protein aliquots were diluted 1:1 with TBSG (100 mM Tris, 80 mM NaCl, 10 (v/v) glycerol, pH 7.4), to a final concentration of 30 mM protein. In all scans, spectra were measured from 190 to 260 nm with a scanning speed of 50 nm/min. The CD spectra were analyzed by spectral deconvolution using the CONTINLL algorithm [63].Supporting InformationFigure S1 Far-UV CD spectra of ataxin-3(Q15) and the Josephin domain during aggregation in the presence of SDS. Protein aliquots were taken from a fibrillogenesis time course assay and the far-UV CD spectra determined. For 23977191 each indicated SDS concentration aliquots were taken at times of 0 hr (black), 4 hr (green), 46 hr (red) and 100 hr (blue). (TIFF) Figure S2 Morphology of fibrils formed by ataxin3(Q15) and Josephin with SDS. Transmission Electron Microscopy of ataxin-3(Q15) with 0 mM (A), 1 mM (B) and 5 mM SDS (C), and Josephin domain with 0 mM.S [47,59,60].methylsulfonyl fluoride, with the addition of 0?0 mM SDS as required. Samples were incubated without shaking at 37uC in airtight containers to prevent evaporation.Thioflavin T FluorescenceThioT fluorescence measurements were recorded on a Gemini platereader, using the buffering conditions described previously with the addition of 30 mM ThT and 0?0 mM SDS. Excitation and emission wavelengths of 430 nm and 480 nm with a cut off filter of 455 nm were used, and both excitation and emission were read from the underneath of a black clear bottom plate. All reactions were completed at 37uC with no shaking.Membrane Filter Trap AssayAliquots containing 7.4 mg of protein were taken from the fibrillogenesis reaction, diluted 1:1 with a 4 (w/v) SDS/100 mM DTT solution and then boiled for 5 min at 100uC. 200 mL of 2 (w/v) SDS was then added to each of the samples, and 5 mg of protein were filtered through a 0.2 mm cellulose acetate membrane (Schleicher and Schuell) using a Bio-Rad Bio-Dot SF microfiltration unit. The membrane was then washed twice by filtering 200 mL of 0.1 (w/v) SDS, and blotted with a hexahistidine (His6) antibody (Serotec). Densitometry was completed using the program Phoretix 1D Quantifier.Materials and Methods MaterialsPhenylmethylsulfonyl fluoride, b-mercaptoethanol and thioT were all obtained from Sigma.Transmission Electron MicroscopyTEM images were obtained using a Hitatchi H7500 transmission electron microscope with an accelerating voltage of 80 kV. The samples were adsorbed onto a carbon-coated grid and stained with 1 (w/v) uranyl acetate.Expression and Purification of Ataxin-3 variantsAll ataxin-3 variants were expressed and purified as previously described 1315463 [61,62], and the proteins were stored at 280uC. Following purification the deubiquitinating activity of the proteins was measured [10] and before use all were analyzed using gel filtration to ensure that no multimeric species were present.Protein-lipid OverlayThe protein-lipid overlay assay was performed using fibrillar protein stopped at various timepoints. The protein was incubated with the phospholipids (PIP Strips, Molecular Probes) overnight at 4uC. Each lipid dot contained 100 pmol of phospholipids. The membrane was then blotted using His6 primary antibody (Serotec) and peroxidase-conjugated secondary antibody as described [64].Circular DichroismFar-UV CD spectra were measured on a Jasco-810 spectropolarimeter at 37uC using a path length of 0.1 mm. Scans of monomeric protein in the presence of different concentrations of SDS were carried out. For time course assays, protein aliquots were diluted 1:1 with TBSG (100 mM Tris, 80 mM NaCl, 10 (v/v) glycerol, pH 7.4), to a final concentration of 30 mM protein. In all scans, spectra were measured from 190 to 260 nm with a scanning speed of 50 nm/min. The CD spectra were analyzed by spectral deconvolution using the CONTINLL algorithm [63].Supporting InformationFigure S1 Far-UV CD spectra of ataxin-3(Q15) and the Josephin domain during aggregation in the presence of SDS. Protein aliquots were taken from a fibrillogenesis time course assay and the far-UV CD spectra determined. For 23977191 each indicated SDS concentration aliquots were taken at times of 0 hr (black), 4 hr (green), 46 hr (red) and 100 hr (blue). (TIFF) Figure S2 Morphology of fibrils formed by ataxin3(Q15) and Josephin with SDS. Transmission Electron Microscopy of ataxin-3(Q15) with 0 mM (A), 1 mM (B) and 5 mM SDS (C), and Josephin domain with 0 mM.