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arXiv · 2112.08651

Dynamic Density Functional Theory of Multicomponent Cellular Membranes

Abstract

We present a continuum model trained on molecular dynamics (MD) simulations for cellular membranes composed of an arbitrary number of lipid types. The model is constructed within the formalism of dynamic density functional theory and can be extended to include features such as the presence of proteins and membrane deformations. This framework represents a paradigm shift by enabling simulations that can access length scales on the order of microns and time scales on the order of seconds, all while maintaining near fidelity to the underlying MD models. These length and time scales are significant for accessing biological processes associated with signaling pathways within cells. Membrane interactions with RAS, a protein implicated in roughly 30% of human cancers, are considered as an application. Simulation results are presented and verified with MD simulations, and implications of this new capability are discussed.

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Liam G. Stanton, Tomas Oppelstrup, Timothy S. Carpenter, Helgi I. Ingólfsson, Michael P. Surh, Felice C. Lightstone, James N. Glosli. 2021-12-16. Dynamic Density Functional Theory of Multicomponent Cellular Membranes. https://doi.org/10.1103/physrevresearch.5.013080

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