Accueil  >  Séminaires  >  Flagella-like beating of actin bundles driven by self-organized myosin waves
Flagella-like beating of actin bundles driven by self-organized myosin waves
Par Pascal MARTIN - Physique des Cellules et Cance - UMR 168, Institut Curie, Paris
Le 17 Décembre 2024 à 11h00 - Laboratoire Jean Perrin - Campus Jussieu - T 22-32- 4e et. - P407

Résumé

Wave-like beating of eukaryotic cilia and flagella - threadlike protrusions found in many cells and microorganisms - is a classic example of spontaneous mechanical oscillations in biology. This type of self-organized active matter raises the question of the coordination mechanism between molecular motor activity and cytoskeletal filament bending. In this talk, I will describe a minimal molecular system in which polymerizing actin filaments in the presence of myosin motors self-assemble into polar filament bundles that undulate spontaneously. The waveforms of these undulations resemble those of the flagellar beat in eukaryotic cells despite the different identities of the filaments and motor at work. Bending waves are associated with motor density waves, indicating that the affinity of myosin for actin depends on the curvature of the filament bundle. A physical description of our observations highlights the importance of internal friction and curvature control of motor activity, which provides a feedback mechanism for the self-organization of large motor-filament assemblies.