A unified model for the dynamics of ATP-independent ultrafast contraction
Year: 2023
Type: article
Abstract: In nature, several ciliated protists possess the remarkable ability to execute ultrafast motions using protein assemblies called myonemes, which contract in response to Ca 2+ ions. Existing theories, such as actomyosin contractility and macroscopic biomechanical latches, do not adequately describe these systems, necessitating new models to understand their mechanisms. In this study, we image and quantitatively analyze the contractile kinematics observed in two ciliated protists ( Vorticella sp and Spirostomum sp ), and, based on the mechanochemistry of these organisms, we propose a minimal mathematical model that reproduces our observations as well as those published previously. Analyzing the model reveals three distinct dynamic regimes, differentiated by the rate of chemical driving and the importance of inertia. We characterize their unique scaling behaviors and kinematic signatures. Besides providing insights into Ca 2+ -powered myoneme contraction in protists, our work may also inform the rational design of ultrafast bioengineered systems such as active synthetic cells.
Language: English
Topic: Micro and Nano Robotics
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Awards: Fundamental principles, limits, and function of ultrafast motion in single cell organisms, Collaborative Research: CYBORG cells: Modular integration of synthetic organelles into living cells, CAREER: Fast, Furious and Fantastic Beasts: Integrative principles, biomechanics and physical limits of impulsive motion in ultrafast organisms, Collaborative Research: CYBORG cells: Modular integration of synthetic organelles into living cells, Collaborative Research: CYBORG cells: Modular integration of synthetic organelles into living cells, Elucidating biophysical mechanisms for force sensing and control using non-equilibrium statistical mechanics and AI, Biophysical mechanism and synthetic engineering of optically-controlled Ca2+-powered supramolecular engines, Mechanics of cell growth and division
OpenAlex ID: W4380366839