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Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments

Actin filament’s polyelectrolyte and hydrodynamic properties, their interactions with the biological environment, and external force fields play an essential role in their biological activities in eukaryotic cellular processes. In this article, we introduce a unique approach that combines dynamics a...

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Autores principales: Alva, Ernesto, George, Annitta, Brancaleon, Lorenzo, Marucho, Marcelo
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9230757/
https://www.ncbi.nlm.nih.gov/pubmed/35746014
http://dx.doi.org/10.3390/polym14122438
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author Alva, Ernesto
George, Annitta
Brancaleon, Lorenzo
Marucho, Marcelo
author_facet Alva, Ernesto
George, Annitta
Brancaleon, Lorenzo
Marucho, Marcelo
author_sort Alva, Ernesto
collection PubMed
description Actin filament’s polyelectrolyte and hydrodynamic properties, their interactions with the biological environment, and external force fields play an essential role in their biological activities in eukaryotic cellular processes. In this article, we introduce a unique approach that combines dynamics and electrophoresis light-scattering experiments, an extended semiflexible worm-like chain model, and an asymmetric polymer length distribution theory to characterize the polyelectrolyte and hydrodynamic properties of actin filaments in aqueous electrolyte solutions. A fitting approach was used to optimize the theories and filament models for hydrodynamic conditions. We used the same sample and experimental conditions and considered several g-actin and polymerization buffers to elucidate the impact of their chemical composition, reducing agents, pH values, and ionic strengths on the filament translational diffusion coefficient, electrophoretic mobility, structure factor, asymmetric length distribution, effective filament diameter, electric charge, zeta potential, and semiflexibility. Compared to those values obtained from molecular structure models, our results revealed a lower value of the effective G-actin charge and a more significant value of the effective filament diameter due to the formation of the double layer of the electrolyte surrounding the filaments. Contrary to the data usually reported from electron micrographs, the lower values of our results for the persistence length and average contour filament length agree with the significant difference in the association rates at the filament ends that shift to sub-micro lengths, which is the maximum of the length distribution.
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spelling pubmed-92307572022-06-25 Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments Alva, Ernesto George, Annitta Brancaleon, Lorenzo Marucho, Marcelo Polymers (Basel) Article Actin filament’s polyelectrolyte and hydrodynamic properties, their interactions with the biological environment, and external force fields play an essential role in their biological activities in eukaryotic cellular processes. In this article, we introduce a unique approach that combines dynamics and electrophoresis light-scattering experiments, an extended semiflexible worm-like chain model, and an asymmetric polymer length distribution theory to characterize the polyelectrolyte and hydrodynamic properties of actin filaments in aqueous electrolyte solutions. A fitting approach was used to optimize the theories and filament models for hydrodynamic conditions. We used the same sample and experimental conditions and considered several g-actin and polymerization buffers to elucidate the impact of their chemical composition, reducing agents, pH values, and ionic strengths on the filament translational diffusion coefficient, electrophoretic mobility, structure factor, asymmetric length distribution, effective filament diameter, electric charge, zeta potential, and semiflexibility. Compared to those values obtained from molecular structure models, our results revealed a lower value of the effective G-actin charge and a more significant value of the effective filament diameter due to the formation of the double layer of the electrolyte surrounding the filaments. Contrary to the data usually reported from electron micrographs, the lower values of our results for the persistence length and average contour filament length agree with the significant difference in the association rates at the filament ends that shift to sub-micro lengths, which is the maximum of the length distribution. MDPI 2022-06-16 /pmc/articles/PMC9230757/ /pubmed/35746014 http://dx.doi.org/10.3390/polym14122438 Text en © 2022 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Alva, Ernesto
George, Annitta
Brancaleon, Lorenzo
Marucho, Marcelo
Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments
title Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments
title_full Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments
title_fullStr Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments
title_full_unstemmed Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments
title_short Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments
title_sort hydrodynamic and polyelectrolyte properties of actin filaments: theory and experiments
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9230757/
https://www.ncbi.nlm.nih.gov/pubmed/35746014
http://dx.doi.org/10.3390/polym14122438
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