α-Synuclein misfolding assessed with single molecule AFM force spectroscopy: effect of pathogenic mutations.
Misfolding and subsequent aggregation of alpha-synuclein (α-Syn) protein are critically involved in the development of several neurodegenerative diseases, including Parkinson's disease (PD). Three familial single point mutations, A30P, E46K, and A53T, correlate with early onset PD; however, the molecular mechanism of the effects of these mutations on the structural properties of α-Syn and its propensity to misfold remains unclear. Here, we address this issue utilizing a single molecule AFM force spectroscopy approach in which structural details of dimers formed by all four variants of α-Syn are characterized. Analysis of the force spectroscopy data reflecting contour length distribution for α-Syn dimer dissociation suggests that multiple segments are involved in the assembly of the dimer. The interactions are not limited to the central nonamyloid-beta component (NAC) of the protein but rather expand beyond this segment. All three mutations alter the protein's folding and interaction patterns affecting interactions far beyond their immediate locations. Implementation of these findings to our understanding of α-Syn aggregation pathways is discussed.
Department of Pharmaceutical Sciences, University of Nebraska Medical Center , 986025 Nebraska Medical Center, Omaha, Nebraska 68198, United States.
Alexey V
AV
Krasnoslobodtsev
Ivan L
IL
Volkov
Josephat M
JM
Asiago
Jagadish
J
Hindupur
Jean-Christophe
JC
Rochet
Yuri L
YL
Lyubchenko
D006801:Humans; D007700:Kinetics; D018625:Microscopy, Atomic Force; D016297:Mutagenesis, Site-Directed; D010300:Parkinson Disease / Q000235:genetics / Q000473:pathology*; D017354:Point Mutation / Q000235:genetics*; D011487:Protein Conformation; D017510:Protein Folding; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000737:chemistry* / Q000235:genetics; D051844:alpha-Synuclein / Q000737:chemistry* / Q000235:genetics
D011994:Recombinant Proteins; D051844:alpha-Synuclein