Light-induced assembly and repeatable actuation in Ca2+-driven chemomechanical protein networks
Xiangting Lei1, Carlos Floyd2, Laura Casas-Ferrer1
1School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
Nature Communications
|February 21, 2026
Summary
Researchers developed a light-controlled soft material using a Tetrahymena thermophila calcium-binding protein 2 (Tcb2) network. This programmable biomaterial exhibits rapid, repeatable motions for applications in synthetic cells and active matter.
Area of Science:
- Biomaterials Science
- Active Matter Physics
- Soft Robotics
Background:
- Programming dynamic motions in soft materials is challenging.
- Existing systems often lack precise control over speed and repeatability.
- Actomyosin systems serve as a benchmark for contractile dynamics.
Purpose of the Study:
- To create a light-controlled chemomechanical network for programmable actuation.
- To investigate the self-assembly, growth, and contraction dynamics of Tcb2 networks.
- To explore applications in active transport and synthetic biology.
Main Methods:
- Utilized Tetrahymena thermophila calcium-binding protein 2 (Tcb2) as a Ca2+-sensitive contractile protein.
- Employed light-sensitive chelators for optically triggered Ca2+ release to control network dynamics.
- Developed a coupled reaction-diffusion and elastic model to analyze chemomechanical behavior.
- Demonstrated in vitro active transport and in silico reinforcement learning for actuation programming.
Main Results:
- Tcb2 networks showed dynamic self-assembly, growth, and contraction rates comparable to actomyosin.
- Achieved precise, optically controlled growth and repeatable mechanical contractility.
- Observed emergent phenomena like boundary-localized active regions and density gradient-driven motion reversals.
- Successfully demonstrated active particle transport and programmed seconds-scale actuation.
Conclusions:
- Established a platform for responsive active materials with tunable optical control.
- Highlighted the interplay between chemical assembly and mechanical response in Tcb2 networks.
- Opened avenues for designing synthetic cells, sub-cellular force generators, and programmable biomaterials.
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