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Adsorption of nanoparticles on a membrane can give rise to interactions between particles, mediated by membrane deformations, that play an important role in self-assembly and membrane remodeling. Previous theoretical and experimental research has focused on nanoparticles with fixed shapes, such as spherical, rod-like, and curved nanoparticles. Recently, hinge-like DNA origami nanostructures have been designed with tunable mechanical properties. Inspired by this, we investigate the equilibrium properties of hinge-like particles adsorbed on an elastic membrane using Monte Carlo and umbrella sampling simulations. The configurations of an isolated particle are influenced by competition between bending energies of the membrane and the particle, which can be controlled by changing adsorption strength and hinge stiffness. When two adsorbed particles interact, they effectively repel one another when the strength of adhesion to the membrane is weak. However, a strong adhesive interaction induces an effective attraction between the particles, which drives their aggregation. The configurations of the aggregate can be tuned by adjusting the hinge stiffness: tip-to-tip aggregation occurs for flexible hinges, whereas tip-to-middle aggregation also occurs for stiffer hinges. Our results highlight the potential for using the mechanical features of deformable nanoparticles to influence their self-assembly when the particles and membrane mutually influence one another.
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This content will become publicly available on May 26, 2026
Lipid membrane remodeling by (bio)polymers and nanoparticles: mechanistic insights from multi-scale simulations
In this chapter, we discuss the analysis of membrane remodeling by proteins, pep- tides and nanoparticles using multi-scale computational methods; these include mainly molecular dynamics simulations at atomistic and coarse-grained levels, al- though we will also touch upon continuum mechanics models. The discussions will cover several systems that we have analyzed in recent studies, which include Sar1, the ESCRTIII complex, complexin and peptides from SARS-COVID-2; as comparison, we also briefly discuss the impact of polyelectrolyte coacervates and functionalized nanoparticles on membrane properties, including generation of membrane curvature and potential disruption of liposomes. These examples illustrate different molecular properties and mechanisms that are potentially relevant to membrane remodeling at different length scales. The results highlight both the values and limitations of different computational models for the analysis of membrane remodeling, thus underscoring the importance of integrating different computational approaches to cross-validate the results.
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- Award ID(s):
- 2154804
- PAR ID:
- 10591407
- Editor(s):
- Bozelli, Jose C; Epand, Richard M
- Publisher / Repository:
- Routledge, Taylor & Francis Group
- Date Published:
- Edition / Version:
- 1
- ISBN:
- 9781032263144
- Page Range / eLocation ID:
- Chapter 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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