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Sakuta H, Fujita F, Hamada T, Hayashi M, Takiguchi K, Tsumoto K, Yoshikawa K. Self-Emergent Protocells Generated in an Aqueous Solution with Binary Macromolecules through Liquid-Liquid Phase Separation. Chembiochem 2020; 21:3323-3328. [PMID: 32667694 PMCID: PMC7754443 DOI: 10.1002/cbic.202000344] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/09/2020] [Indexed: 12/18/2022]
Abstract
Recently, liquid-liquid phase separation (LLPS) has attracted considerable attention among researchers in the life sciences as a plausible mechanism for the generation of microstructures inside cells. LLPS occurs through multiple nonspecific interactions and does not always require a lock-and-key interaction with a binary macromolecular solution. The remarkable features of LLPS include the non-uniform localization and concentration of solutes, resulting in the ability to isolate certain chemical systems and thereby parallelize multiple chemical reactions within the limited space of a living cell. We report that, by using the macromolecules, poly(ethylene glycol) (PEG) and dextran, that exhibit LLPS in an aqueous solution, cell-sized liposomes are spontaneously formed therein in the presence of phospholipids. In this system, LLPS is generated through the depletion effect of macromolecules. The results showed that cell-like microdroplets entrapping DNA wrapped by a phospholipid layer emerge in a self-organized manner.
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Affiliation(s)
- Hiroki Sakuta
- Graduate School of Life and Medical SciencesDoshisha UniversityTataramiyakodani 1–3Kyotanabe, Kyoto610-0394Japan
| | - Fumika Fujita
- Graduate School of Life and Medical SciencesDoshisha UniversityTataramiyakodani 1–3Kyotanabe, Kyoto610-0394Japan
| | - Tsutomu Hamada
- School of Materials ScienceJapan Advanced Institute of Science and TechnologyNomi, Ishikawa923-1292Japan
| | - Masahito Hayashi
- Department of Frontier BioscienceHosei UniversityKoganei, Tokyo184-8584Japan
| | - Kingo Takiguchi
- Graduate School of ScienceNagoya University Furo-cho, Chikusa-kuNagoya, Aichi464-8602Japan
| | - Kanta Tsumoto
- Division of Chemistry for Materials Graduate School of EngineeringMie UniversityKurimamachiya-cho 1577Tsu, Mie514-8507Japan
| | - Kenichi Yoshikawa
- Graduate School of Life and Medical SciencesDoshisha UniversityTataramiyakodani 1–3Kyotanabe, Kyoto610-0394Japan
- Center for Integrative Medicine and PhysicsInstitute for Advanced StudyKyoto UniversityKyoto606-8501Japan
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2
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Nishiyama M. High-pressure microscopy for tracking dynamic properties of molecular machines. Biophys Chem 2017; 231:71-78. [DOI: 10.1016/j.bpc.2017.03.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/24/2017] [Accepted: 03/27/2017] [Indexed: 01/29/2023]
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Kurokawa C, Fujiwara K, Morita M, Kawamata I, Kawagishi Y, Sakai A, Murayama Y, Nomura SIM, Murata S, Takinoue M, Yanagisawa M. DNA cytoskeleton for stabilizing artificial cells. Proc Natl Acad Sci U S A 2017; 114:7228-7233. [PMID: 28652345 PMCID: PMC5514726 DOI: 10.1073/pnas.1702208114] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Cell-sized liposomes and droplets coated with lipid layers have been used as platforms for understanding live cells, constructing artificial cells, and implementing functional biomedical tools such as biosensing platforms and drug delivery systems. However, these systems are very fragile, which results from the absence of cytoskeletons in these systems. Here, we construct an artificial cytoskeleton using DNA nanostructures. The designed DNA oligomers form a Y-shaped nanostructure and connect to each other with their complementary sticky ends to form networks. To undercoat lipid membranes with this DNA network, we used cationic lipids that attract negatively charged DNA. By encapsulating the DNA into the droplets, we successfully created a DNA shell underneath the membrane. The DNA shells increased interfacial tension, elastic modulus, and shear modulus of the droplet surface, consequently stabilizing the lipid droplets. Such drastic changes in stability were detected only when the DNA shell was in the gel phase. Furthermore, we demonstrate that liposomes with the DNA gel shell are substantially tolerant against outer osmotic shock. These results clearly show the DNA gel shell is a stabilizer of the lipid membrane akin to the cytoskeleton in live cells.
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Affiliation(s)
- Chikako Kurokawa
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo 184-8588 Japan
| | - Kei Fujiwara
- Department of Biosciences and Informatics, Keio University, Kanagawa 223-8522, Japan
| | - Masamune Morita
- Department of Computer Science, Tokyo Institute of Technology, Kanagawa 226-8502, Japan
| | - Ibuki Kawamata
- Department of Robotics, Tohoku University, Sendai 980-8579, Japan
| | - Yui Kawagishi
- Department of Robotics, Tohoku University, Sendai 980-8579, Japan
| | - Atsushi Sakai
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo 184-8588 Japan
| | - Yoshihiro Murayama
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo 184-8588 Japan
| | | | - Satoshi Murata
- Department of Robotics, Tohoku University, Sendai 980-8579, Japan
| | - Masahiro Takinoue
- Department of Computer Science, Tokyo Institute of Technology, Kanagawa 226-8502, Japan;
| | - Miho Yanagisawa
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo 184-8588 Japan;
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Hayashi M, Nishiyama M, Kazayama Y, Toyota T, Harada Y, Takiguchi K. Reversible Morphological Control of Tubulin-Encapsulating Giant Liposomes by Hydrostatic Pressure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:3794-3802. [PMID: 27023063 DOI: 10.1021/acs.langmuir.6b00799] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Liposomes encapsulating cytoskeletons have drawn much recent attention to develop an artificial cell-like chemical-machinery; however, as far as we know, there has been no report showing isothermally reversible morphological changes of liposomes containing cytoskeletons because the sets of various regulatory factors, that is, their interacting proteins, are required to control the state of every reaction system of cytoskeletons. Here we focused on hydrostatic pressure to control the polymerization state of microtubules (MTs) within cell-sized giant liposomes (diameters ∼10 μm). MT is the cytoskeleton formed by the polymerization of tubulin, and cytoskeletal systems consisting of MTs are very dynamic and play many important roles in living cells, such as the morphogenesis of nerve cells and formation of the spindle apparatus during mitosis. Using real-time imaging with a high-pressure microscope, we examined the effects of hydrostatic pressure on the morphology of tubulin-encapsulating giant liposomes. At ambient pressure (0.1 MPa), many liposomes formed protrusions due to tubulin polymerization within them. When high pressure (60 MPa) was applied, the protrusions shrank within several tens of seconds. This process was repeatedly inducible (around three times), and after the pressure was released, the protrusions regenerated within several minutes. These deformation rates of the liposomes are close to the velocities of migrating or shape-changing living cells rather than the shortening and elongation rates of the single MTs, which have been previously measured. These results demonstrate that the elongation and shortening of protrusions of giant liposomes is repeatedly controllable by regulating the polymerization state of MTs within them by applying and releasing hydrostatic pressure.
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Affiliation(s)
- Masahito Hayashi
- Division of Biological Science, Graduate School of Science, Nagoya University , Nagoya 464-8602, Japan
| | | | | | | | | | - Kingo Takiguchi
- Division of Biological Science, Graduate School of Science, Nagoya University , Nagoya 464-8602, Japan
- Structural Biology Research Center, Nagoya University , Nagoya 464-8601, Japan
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Kato N, Ishijima A, Inaba T, Nomura F, Takeda S, Takiguchi K. Effects of lipid composition and solution conditions on the mechanical properties of membrane vesicles. MEMBRANES 2015; 5:22-47. [PMID: 25611306 PMCID: PMC4384090 DOI: 10.3390/membranes5010022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 01/07/2015] [Accepted: 01/12/2015] [Indexed: 01/01/2023]
Abstract
The mechanical properties of cell-sized giant unilamellar liposomes were studied by manipulating polystyrene beads encapsulated within the liposomes using double-beam laser tweezers. Mechanical forces were applied to the liposomes from within by moving the beads away from each other, which caused the liposomes to elongate. Subsequently, a tubular membrane projection was generated in the tip at either end of the liposome, or the bead moved out from the laser trap. The force required for liposome transformation reached maximum strength just before formation of the projection or the moving out of the bead. By employing this manipulation system, we investigated the effects of membrane lipid compositions and environment solutions on the mechanical properties. With increasing content of acidic phospholipids, such as phosphatidylglycerol or phosphatidic acid, a larger strength of force was required for the liposome transformation. Liposomes prepared with a synthetic dimyristoylphosphatidylcholine, which has uniform hydrocarbon chains, were transformed easily compared with liposomes prepared using natural phosphatidylcholine. Surprisingly, bovine serum albumin or fetuin (soluble proteins that do not bind to membranes) decreased liposomal membrane rigidity, whereas the same concentration of sucrose showed no particular effect. These results show that the mechanical properties of liposomes depend on their lipid composition and environment.
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Affiliation(s)
- Nobuhiko Kato
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
| | - Akihiko Ishijima
- Institute of Multidisciplinary, Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai 980-8577, Japan.
| | - Takehiko Inaba
- Lipid Biology Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
| | - Fumimasa Nomura
- Department of Biomedical Information, Division of Biosystems, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda, Tokyo 101-0062, Japan.
| | - Shuichi Takeda
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
| | - Kingo Takiguchi
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
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Brüggemann D, Frohnmayer JP, Spatz JP. Model systems for studying cell adhesion and biomimetic actin networks. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:1193-202. [PMID: 25161853 PMCID: PMC4142981 DOI: 10.3762/bjnano.5.131] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 06/25/2014] [Indexed: 05/28/2023]
Abstract
Many cellular processes, such as migration, proliferation, wound healing and tumor progression are based on cell adhesion. Amongst different cell adhesion molecules, the integrin receptors play a very significant role. Over the past decades the function and signalling of various such integrins have been studied by incorporating the proteins into lipid membranes. These proteolipid structures lay the foundation for the development of artificial cells, which are able to adhere to substrates. To build biomimetic models for studying cell shape and spreading, actin networks can be incorporated into lipid vesicles, too. We here review the mechanisms of integrin-mediated cell adhesion and recent advances in the field of minimal cells towards synthetic adhesion. We focus on reconstituting integrins into lipid structures for mimicking cell adhesion and on the incorporation of actin networks and talin into model cells.
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Affiliation(s)
- Dorothea Brüggemann
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg, INF 253, D-69120 Heidelberg, Germany
| | - Johannes P Frohnmayer
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg, INF 253, D-69120 Heidelberg, Germany
| | - Joachim P Spatz
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg, INF 253, D-69120 Heidelberg, Germany
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7
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Weinberger A, Tsai FC, Koenderink GH, Schmidt TF, Itri R, Meier W, Schmatko T, Schröder A, Marques C. Gel-assisted formation of giant unilamellar vesicles. Biophys J 2014; 105:154-64. [PMID: 23823234 DOI: 10.1016/j.bpj.2013.05.024] [Citation(s) in RCA: 244] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 05/06/2013] [Accepted: 05/08/2013] [Indexed: 02/03/2023] Open
Abstract
Giant unilamellar vesicles or GUVs are systems of choice as biomimetic models of cellular membranes. Although a variety of procedures exist for making single walled vesicles of tens of microns in size, the range of lipid compositions that can be used to grow GUVs by the conventional methods is quite limited, and many of the available methods involve energy input that can damage the lipids or other molecules present in the growing solution for embedment in the membrane or in the vesicle interior. Here, we show that a wide variety of lipids or lipid mixtures can grow into GUVs by swelling lipid precursor films on top of a dried polyvinyl alcohol gel surface in a swelling buffer that can contain diverse biorelevant molecules. Moreover, we show that the encapsulation potential of this method can be enhanced by combining polyvinyl alcohol-mediated growth with inverse-phase methods, which allow (bio)molecule complexation with the lipids.
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Affiliation(s)
- Andreas Weinberger
- Institut Charles Sadron (UPR22-CNRS), Université de Strasbourg, Strasbourg, France
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8
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Yanagisawa M, Sakaue T, Yoshikawa K. Characteristic Behavior of Crowding Macromolecules Confined in Cell-Sized Droplets. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 307:175-204. [DOI: 10.1016/b978-0-12-800046-5.00007-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Cabré EJ, Sánchez-Gorostiaga A, Carrara P, Ropero N, Casanova M, Palacios P, Stano P, Jiménez M, Rivas G, Vicente M. Bacterial division proteins FtsZ and ZipA induce vesicle shrinkage and cell membrane invagination. J Biol Chem 2013; 288:26625-34. [PMID: 23921390 DOI: 10.1074/jbc.m113.491688] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Permeable vesicles containing the proto-ring anchoring ZipA protein shrink when FtsZ, the main cell division protein, polymerizes in the presence of GTP. Shrinkage, resembling the constriction of the cytoplasmic membrane, occurs at ZipA densities higher than those found in the cell and is modulated by the dynamics of the FtsZ polymer. In vivo, an excess of ZipA generates multilayered membrane inclusions within the cytoplasm and causes the loss of the membrane function as a permeability barrier. Overproduction of ZipA at levels that block septation is accompanied by the displacement of FtsZ and two additional division proteins, FtsA and FtsN, from potential septation sites to clusters that colocalize with ZipA near the membrane. The results show that elementary constriction events mediated by defined elements involved in cell division can be evidenced both in bacteria and in vesicles.
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Affiliation(s)
- Elisa J Cabré
- From the Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), 28040 Madrid, Spain
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10
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George SP, Chen H, Conrad JC, Khurana S. Regulation of directional cell migration by membrane-induced actin bundling. J Cell Sci 2012; 126:312-26. [PMID: 23132923 DOI: 10.1242/jcs.116244] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
During embryonic development and in metastatic cancers, cells detach from the epithelium and migrate with persistent directionality. Directional cell migration is also crucial for the regeneration and maintenance of the epithelium and impaired directional migration is linked to chronic inflammatory diseases. Despite its significance, the mechanisms controlling epithelial cell migration remain poorly understood. Villin is an epithelial-cell-specific actin modifying protein that regulates epithelial cell plasticity and motility. In motile cells villin is associated with the highly branched and the unbranched actin filaments of lamellipodia and filopodia, respectively. In this study we demonstrate for the first time that villin regulates directionally persistent epithelial cell migration. Functional characterization of wild-type and mutant villin proteins revealed that the ability of villin to self-associate and bundle actin as well as its direct interaction with phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P(2)] regulates villin-induced filopodial assembly and directional cell migration. Our findings suggest that convergence of different signaling cascades could spatially restrict villin activity to areas of high PtdIns(4,5)P(2) and F-actin concentration to assemble filopodia. Furthermore, our data reveal the ability of villin to undergo actin- and PtdIns(4,5)P(2)-induced self-association, which may be particularly suited to coalesce and reorganize actin bundles within the filopodia.
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Affiliation(s)
- Sudeep P George
- Department of Biology and Biochemistry, The University of Houston, Houston, TX 77204, USA
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11
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Vogel SK, Schwille P. Minimal systems to study membrane-cytoskeleton interactions. Curr Opin Biotechnol 2012; 23:758-65. [PMID: 22503237 DOI: 10.1016/j.copbio.2012.03.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 03/21/2012] [Accepted: 03/22/2012] [Indexed: 11/16/2022]
Abstract
In the context of minimal systems design, there are two areas in which the reductionist approach has been particularly successful: studies of molecular motors on cytoskeletal filaments, and of protein-lipid interactions in model membranes. However, a minimal cortex, that is, the interface between membrane and cytoskeleton, has just begun to be functionally reconstituted. A key property of living cells is their ability to change their shape in response to extracellular and intracellular stimuli. Although studied in live cells since decades, the mutual dependence between cytoskeleton and membrane dynamics in these large-scale transformations is still poorly understood. Here we report on inspiring recent in vitro work in this direction, and the promises it holds for a better understanding of key cellular processes.
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Affiliation(s)
- Sven K Vogel
- Max Planck Institute of Biochemistry, Department of Cellular and Molecular Biophysics, Am Klopferspitz 18, D-82152 Martinsried, Germany
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12
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Takiguchi K, Negishi M, Tanaka-Takiguchi Y, Homma M, Yoshikawa K. Transformation of actoHMM assembly confined in cell-sized liposome. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:11528-35. [PMID: 21819144 PMCID: PMC3171996 DOI: 10.1021/la2016287] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
To construct a simple model of a cellular system equipped with motor proteins, cell-sized giant liposomes encapsulating various amounts of actoHMM, the complexes of actin filaments (F-actin) and heavy meromyosin (HMM, an actin-related molecular motor), with a depletion reagent to mimic the crowding effect of inside of living cell, were prepared. We adapted the methodology of the spontaneous transfer of water-in-oil (W/O) droplets through a phospholipid monolayer into the bulk aqueous phase and successfully prepared stable giant liposomes encapsulating the solution with a physiological salt concentration containing the desired concentrations of actoHMM, which had been almost impossible to obtain using currently adapted methodologies such as natural swelling and electro-formation on an electrode. We then examined the effect of ATP on the cytoskeleton components confined in those cell-sized liposomes, because ATP is known to drive the sliding motion for actoHMM. We added α-hemolysin, a bacterial membrane pore-forming toxin, to the bathing solution and obtained liposomes with the protein pores embedded on the bilayer membrane to allow the transfer of ATP inside the liposomes. We show that, by the ATP supply, the actoHMM bundles inside the liposomes exhibit specific changes in spatial distribution, caused by the active sliding between F-actin and HMM. Interestingly, all F-actins localized around the inner periphery of liposomes smaller than a critical size, whereas in the bulk solution and also in larger liposomes, the actin bundles formed aster-like structures under the same conditions.
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Affiliation(s)
- Kingo Takiguchi
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
- Phone: +81-52-789-2993 (K.T.); +81-75-753-3812 (K.Y.). Fax: +81-52-789-3001 (K.T.); +81-75-753-3779 (K.Y.). E-mail: (K.T.); (K.Y.)
| | - Makiko Negishi
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yohko Tanaka-Takiguchi
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Michio Homma
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Kenichi Yoshikawa
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
- Phone: +81-52-789-2993 (K.T.); +81-75-753-3812 (K.Y.). Fax: +81-52-789-3001 (K.T.); +81-75-753-3779 (K.Y.). E-mail: (K.T.); (K.Y.)
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13
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Tsai FC, Stuhrmann B, Koenderink GH. Encapsulation of active cytoskeletal protein networks in cell-sized liposomes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:10061-10071. [PMID: 21707043 DOI: 10.1021/la201604z] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate that cytoskeletal actin-myosin networks can be encapsulated with high efficiency in giant liposomes by hydration of lipids in an agarose hydrogel. The liposomes have cell-sized diameters of 10-20 μm and a uniform actin content. We show by measurements of membrane fluorescence intensity and bending rigidity that the majority of liposomes are unilamellar. We further demonstrate that the actin network can be specifically anchored to the membrane by biotin-streptavidin linkages. These protein-filled liposomes are useful model systems for quantitative studies of the physical mechanisms by which the cytoskeleton actively controls cell shape and mechanics. In a broader context, this new preparation method should be widely applicable to encapsulation of proteins and polymers, for instance, to create polymer-reinforced liposomes for drug delivery.
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Affiliation(s)
- Feng-Ching Tsai
- Biological Soft Matter Group, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
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14
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Ruder WC, Leduc PR. Bioinspirations: cell-inspired small-scale systems for enabling studies in experimental biomechanics. Integr Comp Biol 2011; 51:133-41. [PMID: 21705801 DOI: 10.1093/icb/icr010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Biomechanical forces govern the behaviors of organisms and their environment and examining these behaviors to understand the underlying phenomena is an important challenge. One experimental approach for probing these interactions between organisms and their biomechanical environment uses biologically-inspired, artificial surrogates that reproduce organic mechanical systems. For the case of complex, multicellular organisms, robot surrogates have been particularly effective, such as in the analysis of the fins of fish and insects' wings. This biologically-inspired approach is also exciting when examining cell-scale responses as multicellular organisms' behavior is directly influenced by the integrated interactions of smaller-scale components (i.e., cells). In this review, we introduce the burgeoning field of engineering of artificial cells, which focuses on developing cell-scale entities replicating cellular behaviors. We describe both a bottom-up approach to constructing artificial cells, using molecular components to directly assemble artificial cells, as well as a top-down approach, in which living cells are encapsulated in a single entity whose behavior is determined by its constituent members. In particular, we discuss the potential role of these artificial cells as implantable controllers, designed to alter the mechanical behavior of a host organism. Eventually, artificial cells designed to function as small-scale controllers may help alter organisms' phenotypes.
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Affiliation(s)
- Warren C Ruder
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
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