Phosphorylation and O-GlcNAcylation at the same α-synuclein site generate distinct fibril structures

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: March 27, 2024

Abstract α-Synuclein forms amyloid fibrils that are critical in the progression of Parkinson’s disease and serves as pathological hallmark this condition. Different posttranslational modifications have been identified at multiple sites α-synuclein, influencing its conformation, aggregation function. Here, we investigate how disease-related phosphorylation O-GlcNAcylation same α-synuclein site (S87) affect fibril structure neuropathology. Using semi-synthesis, obtained homogenous monomer with site-specific (pS87) (gS87) S87, respectively. Cryo-EM revealed pS87 gS87 form two distinct structures. The GlcNAc situated S87 establishes interactions K80 E61, inducing a unique iron-like fold molecule on iron handle. Phosphorylation prevents lengthy C-terminal region including residues 73 to 140 from incorporating into core due electrostatic repulsion. Instead, N-terminal half (1–72) takes an arch-like structure. We further show both display reduced neurotoxicity propagation activity compared unmodified fibrils. Our findings demonstrate different can produce structures, which emphasizes link between formation pathology.

Language: Английский

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Single‐Molecule Insight Into α‐Synuclein Fibril Structure and Mechanics Modulated by Chemical Compounds

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 14, 2025

α-Syn fibrils, a key pathological hallmark of Parkinson's disease, is closely associated with disease initiation and progression. Several small molecules are found to bind or dissolve α-syn offering potential therapeutic applications. Here, an innovative optical tweezers-based, fluorescence-combined approach developed probe the mechanical characteristics fibrils at single-molecule level. When subjected axial stretching, local deformation within appeared forces above 50 pN. These structural alternations occurred stepwise irreversible, suggesting unfolding individual subdomains. Additionally, exhibits high heterogeneity in lateral disruption, rupture force ranging from 500 The impact different compounds on structure features further examined. Notably, epigallocatechin gallate (EGCG) generally attenuates by wedging into N-terminal polar groove induces fibril dissociation. Conversely, copper chlorophyllin A (CCA) attaches four sites wrapping around core, reinforcing stability against forces. work offers effective method for characterizing single-fibril properties bridges compound-induced response. insights valuable understanding amyloid mechanics their regulation molecules.

Language: Английский

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Inhibitor Development for α-Synuclein Fibril’s Disordered Region to Alleviate Parkinson’s Disease Pathology

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 27, 2024

The amyloid fibrils of α-synuclein (α-syn) are crucial in the pathology Parkinson's disease (PD), with intrinsically disordered region (IDR) its C-terminal playing a key role interacting receptors like LAG3 and RAGE, facilitating pathological neuronal spread inflammation. In this study, we identified Givinostat (GS) as an effective inhibitor that disrupts interaction α-syn such RAGE through high-throughput screening. By exploring structure-activity relationship optimizing GS, developed several lead compounds, including GSD-16-24. Utilizing solution-state solid-state NMR, along cryo-EM techniques, demonstrated GSD-16-24 binds directly to IDR monomer fibril, preventing fibril from binding receptors. Furthermore, significantly inhibits association membrane receptors, thereby reducing propagation pro-inflammatory effects fibrils. Our findings introduce novel approach mitigate by targeting their small molecules, offering potential leads for development clinical drugs treat PD.

Language: Английский

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Bridging Mechanical Properties with Atomic Structures of Polymorphic α‐Synuclein Fibrils by Single‐Molecule Analysis and Molecular Dynamics Simulations

Aggregate, Journal Year: 2025, Volume and Issue: unknown

Published: March 13, 2025

ABSTRACT α‐Synuclein (α‐syn) forms structurally distinct fibril polymorphs with various pathological activities in different subtypes of synucleinopathies, such as Parkinson's disease (PD). As a unique proteinaceous polymer, the mechanical property α‐syn is primary determinant its neurotoxicity, immunogenicity, and seeding transmission capacity. Nevertheless, how genetic mutations fibrils cause varied polymer behaviors remains largely unknown. Using optical tweezers, we quantitatively characterize properties three variants at single‐molecule level. We find that wild‐type are generally more sustainable to an axial disruption force than those formed by disease‐causing E46K A53T mutants, whereas their heterogeneous elastic manifest similarity. Based on molecular dynamics simulations, β‐sheet motif interface between two protofilaments dominate stabilizing structure. Additionally, simulation analysis consistently reveal force‐driven protein unfolding without break. Due flexible periphery, these subtle structural changes become pronounced fibril. The structure–mechanics relationship built this work sheds new light assembly disassembly mechanism mutant‐associated pathogenesis PD.

Language: Английский

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Proteomic evidence for amyloidogenic cross-seeding in fibrinaloid microclots

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 17, 2024

Abstract In classical amyloidoses, amyloid fibres form through the nucleation and accretion of protein monomers, with protofibrils fibrils exhibiting a cross-β motif parallel or antiparallel β-sheets oriented perpendicular to fibre direction. These can intertwine mature fibres. Similar phenomena occur in blood from individuals circulating inflammatory molecules (also those originating viruses bacteria). presence inflammagens, pathological clotting occur, that results an anomalous termed fibrinaloid microclots. Previous proteomic analyses these microclots have shown non-fibrin(ogen) proteins, suggesting more complex mechanism than simple entrapment. We provide evidence against entrapment model, noting clot pores are too large centrifugation would removed weakly bound proteins. Instead, we explore whether co-aggregation into may involve axial (multiple proteins within same fibril), lateral (single-protein contributing fibre), both types integration. Our analysis data different diseases shows no significant overlap normal plasma proteome correlation between abundance Notably, abundant like α-2-macroglobulin, fibronectin, transthyretin absent microclots, while less such as adiponectin, periostin, von Willebrand Factor well represented. Using bioinformatic tools including AmyloGram AnuPP, found entrapped exhibit high amyloidogenic tendencies, their integration elements structures. This likely contributes microclots’ resistance proteolysis. findings underscore role cross-seeding microclot formation highlight need for further investigation structural properties implications thrombotic diseases. insights foundation developing novel diagnostic therapeutic strategies targeting disorders.

Language: Английский

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Hsp90α forms condensate engaging client proteins with RG motif repeats

Chemical Science, Journal Year: 2024, Volume and Issue: 15(27), P. 10508 - 10518

Published: Jan. 1, 2024

This study reveals that Hsp90α can undergo condensation, and its client proteins feature a high frequency of RG motif repeats. Client with varying patterns exhibit different impacts on the dynamics condensates.

Language: Английский

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Different charged biopolymers induce α-synuclein to form fibrils with distinct structures

Journal of Biological Chemistry, Journal Year: 2024, Volume and Issue: 300(11), P. 107862 - 107862

Published: Oct. 5, 2024

Language: Английский

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Self-limiting multimerization of α-synuclein on membrane and its implication in Parkinson’s diseases

Science Advances, Journal Year: 2024, Volume and Issue: 10(41)

Published: Oct. 9, 2024

α-Synuclein (α-syn), a crucial molecule in Parkinson's disease (PD), is known for its interaction with lipid membranes, which facilitates vesicle trafficking and modulates pathological aggregation. Deciphering the complexity of membrane-binding behavior α-syn to understand functions pathology PD. Here, we used single-molecule imaging show that forms multimers on membranes huge intermultimer distances. The are characterized by self-limiting growth, manifesting concentration-dependent exchanges monomers, fast at micromolar concentrations almost stop nanomolar concentrations. We further uncovered movement patterns α-syn's occasional trapping may be attributed sparse packing defects. Mutations such as E46K E35K disrupt limit resulting larger accelerated amyloid fibril formation. This work emphasizes sophisticated regulation multimerization critical underlying factor PD pathology.

Language: Английский

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Proteomic Evidence for Amyloidogenic Cross-Seeding in Fibrinaloid Microclots

International Journal of Molecular Sciences, Journal Year: 2024, Volume and Issue: 25(19), P. 10809 - 10809

Published: Oct. 8, 2024

In classical amyloidoses, amyloid fibres form through the nucleation and accretion of protein monomers, with protofibrils fibrils exhibiting a cross-β motif parallel or antiparallel β-sheets oriented perpendicular to fibre direction. These can intertwine mature fibres. Similar phenomena occur in blood from individuals circulating inflammatory molecules (and also some originating viruses bacteria). Such pathological clotting result an anomalous termed fibrinaloid microclots. Previous proteomic analyses these microclots have shown presence non-fibrin(ogen) proteins, suggesting more complex mechanism than simple entrapment. We thus provide evidence against such entrapment model, noting that clot pores are too large centrifugation would removed weakly bound proteins. Instead, we explore whether co-aggregation into may involve axial (multiple proteins within same fibril), lateral (single-protein contributing fibre), both types integration. Our analysis data different diseases shows no significant quantitative overlap normal plasma proteome correlation between abundance their Notably, abundant like α-2-macroglobulin, fibronectin, transthyretin absent microclots, while less as adiponectin, periostin, von Willebrand factor well represented. Using bioinformatic tools, including AmyloGram AnuPP, found entrapped exhibit high amyloidogenic tendencies, integration elements structures. This likely contributes microclots’ resistance proteolysis. findings underscore role cross-seeding microclot formation highlight need for further investigation structural properties implications thrombotic diseases. insights foundation developing novel diagnostic therapeutic strategies targeting disorders.

Language: Английский

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Structural polymorphism in amyloids—states within proteins’ solid-state

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 157 - 175

Published: Nov. 22, 2024

Language: Английский

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