Reversible Deformation of Artificial Cell Colonies Triggered by Actin Polymerization for Muscle Behavior Mimicry

Abstract

The use of artificial cells to mimic living tissues is beneficial for understanding the mechanism of interaction among cells. Artificial cells hold immense potential in the field of tissue engineering. Self‐powered artificial cells capable of reversible deformation are developed by encapsulating living mitochondria, actins, and methylcellulose. Upon addition of pyruvate molecules, the mitochondria produce adenosine triphosphate (ATP), which acts as an energy source to trigger actin polymerization. The reversible deformation of artificial cells occurs with a spindle shape resulting from the polymerization of actins to form filaments adjacent to the lipid bilayer that subsequently returns to a spherical shape resulting from the depolymerization of actin filaments upon laser irradiation. The linear colonies composed of these artificial cells exhibit collective contraction and relaxation to mimic muscle tissues. At maximum contraction, the long axis of each giant unilamellar vesicle (GUV) is parallel to each other. All the colonies are synchronized in the contraction phase. The deformation of each GUV in the colonies is influenced by its adjacent GUVs. The muscle‐like artificial cell colonies described here pave the way to develop sustainably self‐powered artificial tissues.

Engineering Tissue-Scale Properties with Synthetic Cells: Forging One from Many

“…Very recently, membrane deformation of synthetic cell colonies through ATP introduction and subsequent actin polymerization has been shown. 217 This is a demonstration of built-in mechanical responses to a chemical stimulus, bringing the idea of responsive synthetic tissue closer to fruition. Judicious patterning of single responsive synthetic cells within larger structures provides an option for anisotropic actuation.…”

“…While these latter two examples are not in lipid-bilayer-based synthetic cells, their work informs future methods seeking to produce tissue-level responses. Very recently, membrane deformation of synthetic cell colonies through ATP introduction and subsequent actin polymerization has been shown . This is a demonstration of built-in mechanical responses to a chemical stimulus, bringing the idea of responsive synthetic tissue closer to fruition.…”

Hierarchical Structuration in Protocellular System

“…[59][60][61][62][63][64][65][66] Due to the dynamic modulation of the internal micro-environment, the internal compartments could be generated through liquid-liquid phase separation (LLPS), [49,50] which could be used to simulate the dynamic formation of membranelles organelles in living cells (Figure 3a). To date, different approaches, including diffusion of signaling molecule, [27,51,67] alteration of pH, [58,68] temperature or osmotic pressure, [34,36,[69][70][71][72][73][74] and light irradiation, [75][76][77][78][79] have been developed to regulate the dynamic LLPS process within a protocell.…”

“…One of the differences between these synthetic cell-like entities and living systems could be due to the lack of spatial control in these protocellular model systems. To date, different approaches have been developed to control the spatial positions within a single protocell or between different protocells, simulating the structural complexity in biological systems, and various cellular functions, including energy conversion, [26,27] intercellular adhesion, [28,29] signalling transduction, [30,31] metabolic reactions, [32] and continuous gene expression, [33][34][35] have been tailored in these hierarchical structured protocellular systems. In this review, we discuss the recent progress in spatial control within a single protocell or between protocells.…”

Light‐Harvesting Artificial Cells for the Generation of ATP and NADPH†

“…[ 5 ] Our recent work introduced a hybrid self‐powered artificial cell, which encapsulated living mitochondria to supply ATP under the stimulation of extra addition of pyruvate molecules. [ 6 ] The produced ATP acted as an energy source to trigger the actin polymerization to induce the reversible deformation of the artificial cell. However, pyruvate molecules needed to be continuously replenished to meet the energy consumption of the system.…”