TY - JOUR
T1 - In situ kinetic measurements of α-synuclein aggregation reveal large population of short-lived oligomers
AU - Zurlo, Enrico
AU - Kumar, Pravin
AU - Meisl, Georg
AU - Dear, Alexander J.
AU - Mondal, Dipro
AU - Claessens, Mireille M.A.E.
AU - Knowles, Tuomas P.J.
AU - Huber, Martina
PY - 2021/1/22
Y1 - 2021/1/22
N2 - Knowledge of the mechanisms of assembly of amyloid proteins into aggregates is of central importance in building an understanding of neurodegenerative disease. Given that oligomeric intermediates formed during the aggregation reaction are believed to be the major toxic species, methods to track such intermediates are clearly needed. Here we present a method, electron paramagnetic resonance (EPR), by which the amount of intermediates can be measured over the course of the aggregation, directly in the reacting solution, without the need for separation. We use this approach to investigate the aggregation of α-synuclein (αS), a synaptic protein implicated in Parkinson's disease and find a large population of oligomeric species. Our results show that these are primary oligomers, formed directly from monomeric species, rather than oligomers formed by secondary nucleation processes, and that they are short-lived, the majority of them dissociates rather than converts to fibrils. As demonstrated here, EPR offers the means to detect such short-lived intermediate species directly in situ. As it relies only on the change in size of the detected species, it will be applicable to a wide range of self-assembling systems, making accessible the kinetics of intermediates and thus allowing the determination of their rates of formation and conversion, key processes in the self-assembly reaction.
AB - Knowledge of the mechanisms of assembly of amyloid proteins into aggregates is of central importance in building an understanding of neurodegenerative disease. Given that oligomeric intermediates formed during the aggregation reaction are believed to be the major toxic species, methods to track such intermediates are clearly needed. Here we present a method, electron paramagnetic resonance (EPR), by which the amount of intermediates can be measured over the course of the aggregation, directly in the reacting solution, without the need for separation. We use this approach to investigate the aggregation of α-synuclein (αS), a synaptic protein implicated in Parkinson's disease and find a large population of oligomeric species. Our results show that these are primary oligomers, formed directly from monomeric species, rather than oligomers formed by secondary nucleation processes, and that they are short-lived, the majority of them dissociates rather than converts to fibrils. As demonstrated here, EPR offers the means to detect such short-lived intermediate species directly in situ. As it relies only on the change in size of the detected species, it will be applicable to a wide range of self-assembling systems, making accessible the kinetics of intermediates and thus allowing the determination of their rates of formation and conversion, key processes in the self-assembly reaction.
UR - http://www.scopus.com/inward/record.url?scp=85100002696&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0245548
DO - 10.1371/journal.pone.0245548
M3 - Article
C2 - 33481908
AN - SCOPUS:85100002696
SN - 1932-6203
VL - 16
JO - PLoS ONE
JF - PLoS ONE
IS - 1
M1 - e0245548
ER -