Blebs lead the way: how to migrate without lamellipodia

@article{Charras2008BlebsLT,
  title={Blebs lead the way: how to migrate without lamellipodia},
  author={Guillaume T. Charras and Ewa K. Paluch},
  journal={Nature Reviews Molecular Cell Biology},
  year={2008},
  volume={9},
  pages={730-736}
}
Blebs are spherical membrane protrusions that are produced by contractions of the actomyosin cortex. Blebs are often considered to be a hallmark of apoptosis; however, blebs are also frequently observed during cytokinesis and during migration in three-dimensional cultures and in vivo. For tumour cells and a number of embryonic cells, blebbing migration seems to be a common alternative to the more extensively studied lamellipodium-based motility. We argue that blebs should be promoted to a more… 

The role and regulation of blebs in cell migration

Cell migration: Fibroblasts find a new way to get ahead

  • M. Sixt
  • Biology
    The Journal of cell biology
  • 2012
TLDR
In some 3D environments, including tissue explants, fibroblasts project different structures, termed lobopodia, at the leading edge; however, similar to membrane blebs, they are driven by actomyosin contraction and do not accumulate active Rac, Cdc42, and phosphatidylinositol 3-kinases.

Fluid migration during bleb formation in cells in vivo

TLDR
It is shown that bleb inflation occurs concomitantly with cytoplasmic inflow into it and that during this process the total cell volume does not change and the bleb formation results primarily from redistribution of material within the cell rather than being driven by flow of water from an external source.

Cell mechanics control rapid transitions between blebs and lamellipodia during migration

TLDR
The data reveal that the type of protrusion formed by migrating cells can be dynamically controlled independently of overall cell morphology, suggesting that protrusion formation is an autonomous module in the regulatory network that controls the plasticity of cell migration.

Fluid dynamics during bleb formation in migrating cells in vivo

TLDR
It is shown that bleb inflation occurs concomitantly with cytoplasmic inflow into it and that during this process the total cell volume does not change and the bleb formation in primordial germ cells results primarily from redistribution of material within the cell rather than being driven by flow of water from an external source.

Blebs—Formation, Regulation, Positioning, and Role in Amoeboid Cell Migration

TLDR
The mechanisms that control the inflation of blebs and bias their formation in the direction of the cell’s leading edge are examined and current views concerning the role blebs play in promoting cell locomotion are presented.

Role of cortical tension in bleb growth

TLDR
It is shown that there is a critical tension below which blebs cannot expand, and this dependence can be fitted with a model of the cortex as an active elastic material, and insights are provided as to how bleb formation can be biochemically regulated during cell motility.

Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes

TLDR
Three-dimensional pseudopods are found to be composed of thin, flat sheets that sometimes interleave to form rosettes, and their laminar nature is not templated by an external surface, but likely reflects a linear arrangement of regulatory molecules.

How blebs and pseudopods cooperate during chemotaxis

TLDR
It is shown that blebs form in concave regions of the plasma membrane of migrating Dictyostelium cells and proposed that the underlying physical reason is due to membrane tension, which provides an outward force at concavities.
...

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TLDR
It is shown that Dictyostelium cells moving in a physiological milieu continuously produce `blebs' at their leading edges, and that focal blebbing contributes greatly to their locomotion, and concludes that amoeboid motility comprises two mechanically different processes characterized by the production of two distinct cell-surface protrusions, blebs and filopodia-lamellipodia.

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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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SURFACE SPECIALIZATIONS OF FUNDULUS CELLS AND THEIR RELATION TO CELL MOVEMENTS DURING GASTRULATION

Cell movements in Fundulus blastoderms during gastrulation were studied utilizing time-lapse cinemicrography and electron microscopy. Time-lapse films reveal that cells of the enveloping layer
...