Effect of acidic pH on the stability of α-synuclein dimers

Zhengjian Lv, Alexey V Krasnoslobodtsev, Yuliang Zhang, Daniel Ysselstein, Jean Christophe Rochet, Scott C. Blanchard, Yuri L Lyubchenko

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Environmental factors, such as acidic pH, facilitate the assembly of α-synuclein (α-Syn) in aggregates, but the impact of pH on the very first step of α-Syn aggregation remains elusive. Recently, we developed a single-molecule approach that enabled us to measure directly the stability of α-Syn dimers. Unlabeled α-Syn monomers were immobilized on a substrate, and fluorophore-labeled monomers were added to the solution to allow them to form dimers with immobilized α-Syn monomers. The dimer lifetimes were measured directly from the fluorescence bursts on the time trajectories. Herein, we applied the single-molecule tethered approach for probing of intermolecular interaction to characterize the effect of acidic pH on the lifetimes of α-Syn dimers. The experiments were performed at pH 5 and 7 for wild-type α−Syn and for two mutants containing familial type mutations E46K and A53T. We demonstrate that a decrease of pH resulted in more than threefold increase in the α-Syn dimers lifetimes with some variability between the α-Syn species. We hypothesize that the stabilization effect is explained by neutralization of residues 96–140 of α-Syn and this electrostatic effect facilitates the association of the two monomers. Given that dimerization is the first step of α-Syn aggregation, we posit that the electrostatic effect thereby contributes to accelerating α-Syn aggregation at acidic pH.

Original languageEnglish (US)
Pages (from-to)715-724
Number of pages10
JournalBiopolymers
DOIs
StatePublished - Oct 1 2016

Fingerprint

Synucleins
Dimers
Monomers
Agglomeration
Electrostatics
Static Electricity
Molecules
Dimerization
Fluorophores
Stabilization
Fluorescence
Trajectories
Association reactions
Substrates
Mutation

Keywords

  • alpha-synuclein protein
  • amyloid aggregation
  • interprotein interactions
  • protein self-assembly
  • single molecule fluorescence

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Biomaterials
  • Organic Chemistry

Cite this

Effect of acidic pH on the stability of α-synuclein dimers. / Lv, Zhengjian; Krasnoslobodtsev, Alexey V; Zhang, Yuliang; Ysselstein, Daniel; Rochet, Jean Christophe; Blanchard, Scott C.; Lyubchenko, Yuri L.

In: Biopolymers, 01.10.2016, p. 715-724.

Research output: Contribution to journalArticle

Lv Z, Krasnoslobodtsev AV, Zhang Y, Ysselstein D, Rochet JC, Blanchard SC et al. Effect of acidic pH on the stability of α-synuclein dimers. Biopolymers. 2016 Oct 1;715-724. https://doi.org/10.1002/bip.22874
Lv, Zhengjian ; Krasnoslobodtsev, Alexey V ; Zhang, Yuliang ; Ysselstein, Daniel ; Rochet, Jean Christophe ; Blanchard, Scott C. ; Lyubchenko, Yuri L. / Effect of acidic pH on the stability of α-synuclein dimers. In: Biopolymers. 2016 ; pp. 715-724.
@article{6e50c1ec78f34dddbe26dca2169ae181,
title = "Effect of acidic pH on the stability of α-synuclein dimers",
abstract = "Environmental factors, such as acidic pH, facilitate the assembly of α-synuclein (α-Syn) in aggregates, but the impact of pH on the very first step of α-Syn aggregation remains elusive. Recently, we developed a single-molecule approach that enabled us to measure directly the stability of α-Syn dimers. Unlabeled α-Syn monomers were immobilized on a substrate, and fluorophore-labeled monomers were added to the solution to allow them to form dimers with immobilized α-Syn monomers. The dimer lifetimes were measured directly from the fluorescence bursts on the time trajectories. Herein, we applied the single-molecule tethered approach for probing of intermolecular interaction to characterize the effect of acidic pH on the lifetimes of α-Syn dimers. The experiments were performed at pH 5 and 7 for wild-type α−Syn and for two mutants containing familial type mutations E46K and A53T. We demonstrate that a decrease of pH resulted in more than threefold increase in the α-Syn dimers lifetimes with some variability between the α-Syn species. We hypothesize that the stabilization effect is explained by neutralization of residues 96–140 of α-Syn and this electrostatic effect facilitates the association of the two monomers. Given that dimerization is the first step of α-Syn aggregation, we posit that the electrostatic effect thereby contributes to accelerating α-Syn aggregation at acidic pH.",
keywords = "alpha-synuclein protein, amyloid aggregation, interprotein interactions, protein self-assembly, single molecule fluorescence",
author = "Zhengjian Lv and Krasnoslobodtsev, {Alexey V} and Yuliang Zhang and Daniel Ysselstein and Rochet, {Jean Christophe} and Blanchard, {Scott C.} and Lyubchenko, {Yuri L}",
year = "2016",
month = "10",
day = "1",
doi = "10.1002/bip.22874",
language = "English (US)",
pages = "715--724",
journal = "Biopolymers",
issn = "0006-3525",
publisher = "John Wiley and Sons Inc.",

}

TY - JOUR

T1 - Effect of acidic pH on the stability of α-synuclein dimers

AU - Lv, Zhengjian

AU - Krasnoslobodtsev, Alexey V

AU - Zhang, Yuliang

AU - Ysselstein, Daniel

AU - Rochet, Jean Christophe

AU - Blanchard, Scott C.

AU - Lyubchenko, Yuri L

PY - 2016/10/1

Y1 - 2016/10/1

N2 - Environmental factors, such as acidic pH, facilitate the assembly of α-synuclein (α-Syn) in aggregates, but the impact of pH on the very first step of α-Syn aggregation remains elusive. Recently, we developed a single-molecule approach that enabled us to measure directly the stability of α-Syn dimers. Unlabeled α-Syn monomers were immobilized on a substrate, and fluorophore-labeled monomers were added to the solution to allow them to form dimers with immobilized α-Syn monomers. The dimer lifetimes were measured directly from the fluorescence bursts on the time trajectories. Herein, we applied the single-molecule tethered approach for probing of intermolecular interaction to characterize the effect of acidic pH on the lifetimes of α-Syn dimers. The experiments were performed at pH 5 and 7 for wild-type α−Syn and for two mutants containing familial type mutations E46K and A53T. We demonstrate that a decrease of pH resulted in more than threefold increase in the α-Syn dimers lifetimes with some variability between the α-Syn species. We hypothesize that the stabilization effect is explained by neutralization of residues 96–140 of α-Syn and this electrostatic effect facilitates the association of the two monomers. Given that dimerization is the first step of α-Syn aggregation, we posit that the electrostatic effect thereby contributes to accelerating α-Syn aggregation at acidic pH.

AB - Environmental factors, such as acidic pH, facilitate the assembly of α-synuclein (α-Syn) in aggregates, but the impact of pH on the very first step of α-Syn aggregation remains elusive. Recently, we developed a single-molecule approach that enabled us to measure directly the stability of α-Syn dimers. Unlabeled α-Syn monomers were immobilized on a substrate, and fluorophore-labeled monomers were added to the solution to allow them to form dimers with immobilized α-Syn monomers. The dimer lifetimes were measured directly from the fluorescence bursts on the time trajectories. Herein, we applied the single-molecule tethered approach for probing of intermolecular interaction to characterize the effect of acidic pH on the lifetimes of α-Syn dimers. The experiments were performed at pH 5 and 7 for wild-type α−Syn and for two mutants containing familial type mutations E46K and A53T. We demonstrate that a decrease of pH resulted in more than threefold increase in the α-Syn dimers lifetimes with some variability between the α-Syn species. We hypothesize that the stabilization effect is explained by neutralization of residues 96–140 of α-Syn and this electrostatic effect facilitates the association of the two monomers. Given that dimerization is the first step of α-Syn aggregation, we posit that the electrostatic effect thereby contributes to accelerating α-Syn aggregation at acidic pH.

KW - alpha-synuclein protein

KW - amyloid aggregation

KW - interprotein interactions

KW - protein self-assembly

KW - single molecule fluorescence

UR - http://www.scopus.com/inward/record.url?scp=84979066474&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84979066474&partnerID=8YFLogxK

U2 - 10.1002/bip.22874

DO - 10.1002/bip.22874

M3 - Article

C2 - 27177831

AN - SCOPUS:84979066474

SP - 715

EP - 724

JO - Biopolymers

JF - Biopolymers

SN - 0006-3525

ER -