Single particle detection and characterization of synuclein co-aggregation.
Protein aggregation is the key event in a number of human diseases such as Alzheimer's and Parkinson's disease. We present a general method to quantify and characterize protein aggregates by dual-colour scanning for intensely fluorescent targets (SIFT). In addition to high sensitivity, this approach offers a unique opportunity to study co-aggregation processes. As the ratio of two fluorescently labelled components can be analysed for each aggregate separately in a homogeneous assay, the molecular composition of aggregates can be studied even in samples containing a mixture of different types of aggregates. Using this method, we could show that wild-type alpha-synuclein forms co-aggregates with a mutant variant found in familial Parkinson's disease. Moreover, we found a striking increase in aggregate formation at non-equimolar mixing ratios, which may have important therapeutic implications, as lowering the relative amount of aberrant protein may cause an increase of protein aggregation leading to adverse effects.
Giese
Armin
A
Center for Neuropathology and Prion Research, LMU, Munich, Germany. Armin.Giese@med.uni-muenchen.de
Bader
Benedikt
B
Bieschke
Jan
J
Schaffar
Gregor
G
Odoy
Sabine
S
Kahle
Philipp J
PJ
Haass
Christian
C
Kretzschmar
Hans
H
D000682:Amyloid / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure*; D001665:Binding Sites; D019281:Dimerization; D046912:Multiprotein Complexes / Q000032:analysis / Q000737:chemistry / Q000648:ultrastructure; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure*; D011485:Protein Binding; D013050:Spectrometry, Fluorescence / Q000379:methods*; D051843:Synucleins; D051844:alpha-Synuclein
D000682:Amyloid; D046912:Multiprotein Complexes; D009419:Nerve Tissue Proteins; D051843:Synucleins; D051844:alpha-Synuclein