Biomimetic Liposome Model Systems to Study Cell Shape Control by the Cytoskeleton

Tsai, Feng-Ching; Roth, Sophie; Dogterom, Marileen; Koenderink, Gijsje H.

doi:10.1016/b978-0-12-418699-6.00006-0

Cited by 5 publications

(5 citation statements)

References 257 publications

(349 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note that when the cell/vesicle is stretched by the rod-like structure, the bending energy of the membrane is increased. The limitation of our simulations is that we did not consider the competition between the membrane bending and the bending of actin filaments or actin filament bundles [ 184 , 185 , 186 ], i.e., the lenght of the actin cytoskeleton is fixed by the constraint (see Figure 23 , Figure 24 and Figure 25 ). A large increase of the membrane bending energy as a consequence of the membrane stretching could have an effect on the length and the shape of the actin cytoskeleton structure, e.g., it could cause the buckling effect, which cannot be taken into account in our modelling ( Figure 23 , Figure 24 and Figure 25 ) [ 185 , 186 , 187 ].…”

Section: Cytoskeleton and Cell Shapementioning

confidence: 99%

On the Role of Curved Membrane Nanodomains and Passive and Active Skeleton Forces in the Determination of Cell Shape and Membrane Budding

Mesarec

Drab

Penič

et al. 2021

IJMS

View full text Add to dashboard Cite

Biological membranes are composed of isotropic and anisotropic curved nanodomains. Anisotropic membrane components, such as Bin/Amphiphysin/Rvs (BAR) superfamily protein domains, could trigger/facilitate the growth of membrane tubular protrusions, while isotropic curved nanodomains may induce undulated (necklace-like) membrane protrusions. We review the role of isotropic and anisotropic membrane nanodomains in stability of tubular and undulated membrane structures generated or stabilized by cyto- or membrane-skeleton. We also describe the theory of spontaneous self-assembly of isotropic curved membrane nanodomains and derive the critical concentration above which the spontaneous necklace-like membrane protrusion growth is favorable. We show that the actin cytoskeleton growth inside the vesicle or cell can change its equilibrium shape, induce higher degree of segregation of membrane nanodomains or even alter the average orientation angle of anisotropic nanodomains such as BAR domains. These effects may indicate whether the actin cytoskeleton role is only to stabilize membrane protrusions or to generate them by stretching the vesicle membrane. Furthermore, we demonstrate that by taking into account the in-plane orientational ordering of anisotropic membrane nanodomains, direct interactions between them and the extrinsic (deviatoric) curvature elasticity, it is possible to explain the experimentally observed stability of oblate (discocyte) shapes of red blood cells in a broad interval of cell reduced volume. Finally, we present results of numerical calculations and Monte-Carlo simulations which indicate that the active forces of membrane skeleton and cytoskeleton applied to plasma membrane may considerably influence cell shape and membrane budding.

show abstract

Section: Cytoskeleton and Cell Shapementioning

confidence: 99%

On the Role of Curved Membrane Nanodomains and Passive and Active Skeleton Forces in the Determination of Cell Shape and Membrane Budding

Mesarec

Drab

Penič

et al. 2021

IJMS

View full text Add to dashboard Cite

show abstract

“…The trigger for polymerization differs per cytoskeletal component. For example, actin polymerization can be triggered using magnesium ions [68], whereas microtubule polymerization is often controlled by the addition of GTP [114]. One popular approach is to ensure that the encapsulation process proceeds more quickly than the polymerization process by performing the encapsulation process at a low temperature [115].…”

Section: Triggering Cytoskeletal Polymerization In Situmentioning

confidence: 99%

“…iop.org/PhysBio/15/041001/mmedia). For information on earlier reports we direct the interested reader to previous review articles [96,114].…”

Section: Introductionmentioning

confidence: 99%

Shaping up synthetic cells

2018

View full text Add to dashboard Cite

How do the cells in our body reconfigure their shape to achieve complex tasks like migration and mitosis, yet maintain their shape in response to forces exerted by, for instance, blood flow and muscle action? Cell shape control is defined by a delicate mechanical balance between active force generation and passive material properties of the plasma membrane and the cytoskeleton. The cytoskeleton forms a space-spanning fibrous network comprising three subsystems: actin, microtubules and intermediate filaments. Bottom-up reconstitution of minimal synthetic cells where these cytoskeletal subsystems are encapsulated inside a lipid vesicle provides a powerful avenue to dissect the force balance that governs cell shape control. Although encapsulation is technically demanding, a steady stream of advances in this technique has made the reconstitution of shape-changing minimal cells increasingly feasible. In this topical review we provide a route-map of the recent advances in cytoskeletal encapsulation techniques and outline recent reports that demonstrate shape change phenomena in simple biomimetic vesicle systems. We end with an outlook toward the next steps required to achieve more complex shape changes with the ultimate aim of building a fully functional synthetic cell with the capability to autonomously grow, divide and move.

show abstract

“…Both experimental and computational efforts have shown that confinement can modulate the organization of actin filaments even in the absence of crosslinking proteins. Experimental studies in vitro have examined the organization of actin filaments in confined regions such as microfabricated shallow chambers (28)(29)(30) and vesicles (9,(31)(32)(33)(34). Theoretical studies have shown the formation of coils and loops by long semiflexible filaments in spherical cavities (35,36).…”

Section: Introductionmentioning

confidence: 99%

Organization and Dynamics of Crosslinked Actin Filaments in Confined Environments

Akenuwa

Abel

2022

Preprint

View full text Add to dashboard Cite

The organization of the actin cytoskeleton is impacted by the interplay between physical confinement, features of crosslinking proteins, and deformations of semiflexible actin filaments. Some crosslinking proteins preferentially bind filaments in parallel, while others bind more indiscriminately. However, a quantitative understanding of how the mode of binding influences the assembly of actin networks in confined environments is lacking. Here we employ coarse-grained computer simulations to study the dynamics and organization of semiflexible actin filaments in confined regions upon the addition of crosslinkers. We characterize how the emergent behavior is influenced by the system shape, the number and type of crosslinking proteins, and the length of filaments. Structures include isolated clusters of filaments, highly connected filament bundles, and networks of interconnected bundles and loops. Elongation of one dimension of the system promotes the formation of long bundles that align with the elongated axis. Dynamics are governed by rapid crosslinking into aggregates, followed by a slower change in their shape and connectivity. Crosslinking decreases the average bending energy of short or sparsely connected filaments by suppressing shape fluctuations. However, it increases the average bending energy in highly connected networks because filament bundles become deformed and small numbers of filaments exhibit long-lived, highly unfavorable configurations. Indiscriminate crosslinking promotes the formation of high-energy configurations due to the increased likelihood of unfavorable, difficult-to-relax configurations at early times. Taken together, this work demonstrates physical mechanisms by which crosslinker binding and physical confinement impact the emergent behavior of actin networks, which is relevant both in cells and in synthetic environments.

show abstract

Biomimetic Liposome Model Systems to Study Cell Shape Control by the Cytoskeleton

Cited by 5 publications

References 257 publications

On the Role of Curved Membrane Nanodomains and Passive and Active Skeleton Forces in the Determination of Cell Shape and Membrane Budding

On the Role of Curved Membrane Nanodomains and Passive and Active Skeleton Forces in the Determination of Cell Shape and Membrane Budding

Shaping up synthetic cells

Organization and Dynamics of Crosslinked Actin Filaments in Confined Environments

Contact Info

Product

Resources

About