Figure 1From: Posttranslational modification and mutation of histidine 50 trigger alpha synuclein aggregation and toxicity HNE modification of WT and H50 mutant aSyn. A) Recombinant WT aSyn treated with different concentrations of HNE (0 - 3000 μM) for 24 h was digested by GluC in order to measure HNE modification of the H50 containing peptide 47GVVHGVATVAE57 by MALDI-TOF analysis. The modification of this peptide (*observed monoisotopic mass to charge ratio m/z: 1038) by HNE leads to a mass increase of 156 Da (↓ observed monoisotopic m/z: 1194). B) aSyn H50Q and H50R mutations completely abolish HNE modification of the corresponding peptides containing the residue 50. Only unmodified peptides, i.e. 47GVVQGVATVAE57 (*observed monoisotopic m/z: 1029) of the H50Q aSyn and 47GVVRGVATVAE57 (*observed monoisotopic m/z: 1057) of the H50R aSyn, are observed. C) Recombinant full-length WT and H50Q/R aSyn were treated with different HNE concentrations for 24 h and analyzed by MALDI-TOF MS. Unmodified (*) and HNE-modified (↓) aSyn (WT, H50Q, and H50R) with a characteristic mass difference of 156 Da are indicated. H50Q/R mutations reduce the formation of aSyn-HNE-adducts, particularly they prevent the modification by HNE at low concentrations (50 - 200 μM).Back to article page