Synergistic Amyloid Switch Triggered by Early Heterotypic Oligomerization of Intrinsically Disordered α-Synuclein and Tau

Copyright © 2018 Elsevier Ltd. All rights reserved..

Amyloidogenic intrinsically disordered proteins, α-synuclein and tau are linked to Parkinson's disease and Alzheimer's disease, respectively. A body of evidence suggests that α-synuclein and tau, both present in the presynaptic nerve terminals, co-aggregate in many neurological ailments. The molecular mechanism of α-synuclein-tau hetero-assembly is poorly understood. Here we show that amyloid formation is synergistically facilitated by heterotypic association mediated by binding-induced misfolding of both α-synuclein and tau K18. We demonstrate that the intermolecular association is largely driven by the electrostatic interaction between the negatively charged C-terminal segment of α-synuclein and the positively charged tau K18 fragment. This heterotypic association results in rapid formation of oligomers that readily mature into hetero-fibrils with a much shorter lag phase compared to the individual proteins. These findings suggested that the critical intermolecular interaction between α-synuclein and tau can promote facile amyloid formation that can potentially lead to efficient sequestration of otherwise long-lived lethal oligomeric intermediates into innocuous fibrils. We next show that a well-known familial Parkinson's disease mutant (A30P) that is known to aggregate slowly via accumulation of highly toxic oligomeric species during the long lag phase converts into amyloid fibrils significantly faster in the presence of tau K18. The early intermolecular interaction profoundly accelerates the fibrillation rate of A30P α-synuclein and impels the disease mutant to behave similar to wild-type α-synuclein in the presence of tau. Our findings suggest a mechanistic underpinning of bypassing toxicity and suggest a general strategy by which detrimental amyloidogenic precursors are efficiently sequestered into more benign amyloid fibrils.

Medienart:

E-Artikel

Erscheinungsjahr:

2018

Erschienen:

2018

Enthalten in:

Zur Gesamtaufnahme - volume:430

Enthalten in:

Journal of molecular biology - 430(2018), 16 vom: 03. Aug., Seite 2508-2520

Sprache:

Englisch

Beteiligte Personen:

Bhasne, Karishma [VerfasserIn]
Sebastian, Sanjana [VerfasserIn]
Jain, Neha [VerfasserIn]
Mukhopadhyay, Samrat [VerfasserIn]

Links:

Volltext

Themen:

Alpha-Synuclein
Amyloid
Amyloid formation
Fluorescence spectroscopy
Intrinsically disordered proteins
Journal Article
K3Z4F929H6
Lysine
MAPT protein, human
Oligomers
Parkinson's disease
Protein Aggregates
Research Support, Non-U.S. Gov't
SNCA protein, human
Tau Proteins

Anmerkungen:

Date Completed 01.07.2019

Date Revised 01.07.2019

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jmb.2018.04.020

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM283519975