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Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)

In present study, we set out to investigate the conformation dynamics of Aβ(40) and Aβ(42) through exploring the impact of intra-molecular interactions on conformation dynamics using equilibrium molecular dynamics simulations. Our 40 microsecond-scale simulations reveal heterogeneous conformation en...

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Autores principales: Song, Wanling, Wang, Yuanyuan, Colletier, Jacques-Philippe, Yang, Huaiyu, Xu, Yechun
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4603783/
https://www.ncbi.nlm.nih.gov/pubmed/26046578
http://dx.doi.org/10.1038/srep11024
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author Song, Wanling
Wang, Yuanyuan
Colletier, Jacques-Philippe
Yang, Huaiyu
Xu, Yechun
author_facet Song, Wanling
Wang, Yuanyuan
Colletier, Jacques-Philippe
Yang, Huaiyu
Xu, Yechun
author_sort Song, Wanling
collection PubMed
description In present study, we set out to investigate the conformation dynamics of Aβ(40) and Aβ(42) through exploring the impact of intra-molecular interactions on conformation dynamics using equilibrium molecular dynamics simulations. Our 40 microsecond-scale simulations reveal heterogeneous conformation ensembles of Aβ(40) and Aβ(42) that encompass ~35% β-strand and ~60% unstructured coils. Two conformational states were identified in both alloforms: a collapsed state (CS) that resembles the structural motif of face-to-face hydrophobic clustering in amyloid fibrils, and an extended state (ES) that features the structural characteristics of anti-parallel β-sheets in amyloid oligomers. In Aβ(40), the C-terminus remains unstructured and rarely interacts with other parts, thereof the hydrophobic clustering is in loose contact and the peptide assumes ES with high probability. In contrast, the C-terminus of Aβ(42) adopts a β-strand structure that strongly interacts with segments E3-R5 and V18-A21. The active association leads to a more compact hydrophobic collapse and refrain the alloform from ES. Based on the structural characterization, we propose that the fibril and oligomer assembly pathways could respectively take off from CS and ES, and their aggregation propensity may be governed by the probability of visiting the corresponding conformational states at the equilibrium.
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spelling pubmed-46037832015-10-23 Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42) Song, Wanling Wang, Yuanyuan Colletier, Jacques-Philippe Yang, Huaiyu Xu, Yechun Sci Rep Article In present study, we set out to investigate the conformation dynamics of Aβ(40) and Aβ(42) through exploring the impact of intra-molecular interactions on conformation dynamics using equilibrium molecular dynamics simulations. Our 40 microsecond-scale simulations reveal heterogeneous conformation ensembles of Aβ(40) and Aβ(42) that encompass ~35% β-strand and ~60% unstructured coils. Two conformational states were identified in both alloforms: a collapsed state (CS) that resembles the structural motif of face-to-face hydrophobic clustering in amyloid fibrils, and an extended state (ES) that features the structural characteristics of anti-parallel β-sheets in amyloid oligomers. In Aβ(40), the C-terminus remains unstructured and rarely interacts with other parts, thereof the hydrophobic clustering is in loose contact and the peptide assumes ES with high probability. In contrast, the C-terminus of Aβ(42) adopts a β-strand structure that strongly interacts with segments E3-R5 and V18-A21. The active association leads to a more compact hydrophobic collapse and refrain the alloform from ES. Based on the structural characterization, we propose that the fibril and oligomer assembly pathways could respectively take off from CS and ES, and their aggregation propensity may be governed by the probability of visiting the corresponding conformational states at the equilibrium. Nature Publishing Group 2015-06-05 /pmc/articles/PMC4603783/ /pubmed/26046578 http://dx.doi.org/10.1038/srep11024 Text en Copyright © 2015, Macmillan Publishers Limited http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
spellingShingle Article
Song, Wanling
Wang, Yuanyuan
Colletier, Jacques-Philippe
Yang, Huaiyu
Xu, Yechun
Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)
title Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)
title_full Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)
title_fullStr Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)
title_full_unstemmed Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)
title_short Varied Probability of Staying Collapsed/Extended at the Conformational Equilibrium of Monomeric Aβ(40) and Aβ(42)
title_sort varied probability of staying collapsed/extended at the conformational equilibrium of monomeric aβ(40) and aβ(42)
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4603783/
https://www.ncbi.nlm.nih.gov/pubmed/26046578
http://dx.doi.org/10.1038/srep11024
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