Theory of active self-organization of dense nematic structures in the actin cytoskeleton

Mirza, Waleed ; De Corato, Marco (Universidad de Zaragoza) ; Pensalfini, Marco ; Vilanova, Guillermo ; Torres-Sánchez, Alejandro ; Arroyo, Marino

Resumen: The actin cytoskeleton is remarkably adaptable and multifunctional. It often organizes into nematic bundles such as contractile rings or stress fibers. However, how a uniform and isotropic actin gel self-organizes into dense nematic bundles is not fully understood. Here, using an active gel model accounting for nematic order and density variations, we identify an active patterning mechanism leading to localized dense nematic structures. Linear stability analysis and nonlinear finite element simulations establish the conditions for nematic bundle self-assembly and how active gel parameters control the architecture, orientation, connectivity, and dynamics of self-organized patterns. Finally, we substantiate with discrete network simulations the main requirements for nematic bundle formation according to our theory, namely increased active tension perpendicular to the nematic direction and generalized active forces conjugate to nematic order. Our work portrays actin gels as reconfigurable active materials with a spontaneous tendency to develop patterns of dense nematic bundles.

Idioma: Inglés

DOI: 10.7554/eLife.93097

Año: 2025

Publicado en: eLife 13 (2025), [33 pp.]
ISSN: 2050-084X

Financiación: info:eu-repo/grantAgreement/ES/MICINN/ICJ2018-035270-I

Tipo y forma: Article (Published version)

Área (Departamento): Área Mecánica de Fluidos (Dpto. Ciencia Tecnol.Mater.Fl.)