scholarly journals Rotating for elongation: Fat2 whips for the race

2016 ◽  
Vol 212 (5) ◽  
pp. 487-489 ◽  
Author(s):  
Tomke Stürner ◽  
Gaia Tavosanis

Dynamic rearrangements of the actin cytoskeleton are crucial for cell shape and migration. In this issue, Squarr et al. (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201508081) show that the cadherin superfamily protein Fat2 regulates actin-rich protrusions driving collective cell migration during Drosophila melanogaster egg morphogenesis through its interaction with the WAVE regulatory complex.

2016 ◽  
Vol 212 (5) ◽  
pp. 591-603 ◽  
Author(s):  
Anna Julia Squarr ◽  
Klaus Brinkmann ◽  
Baoyu Chen ◽  
Tim Steinbacher ◽  
Klaus Ebnet ◽  
...  

Directional cell movements during morphogenesis require the coordinated interplay between membrane receptors and the actin cytoskeleton. The WAVE regulatory complex (WRC) is a conserved actin regulator. Here, we found that the atypical cadherin Fat2 recruits the WRC to basal membranes of tricellular contacts where a new type of planar-polarized whip-like actin protrusion is formed. Loss of either Fat2 function or its interaction with the WRC disrupts tricellular protrusions and results in the formation of nonpolarized filopodia. We provide further evidence for a molecular network in which the receptor tyrosine phosphatase Dlar interacts with the WRC to couple the extracellular matrix, the membrane, and the actin cytoskeleton during egg elongation. Our data uncover a mechanism by which polarity information can be transduced from a membrane receptor to a key actin regulator to control collective follicle cell migration during egg elongation. 4D-live imaging of rotating MCF10A mammary acini further suggests an evolutionary conserved mechanism driving rotational motions in epithelial morphogenesis.


2016 ◽  
Vol 212 (2) ◽  
pp. 199-217 ◽  
Author(s):  
Cédric Plutoni ◽  
Elsa Bazellieres ◽  
Maïlys Le Borgne-Rochet ◽  
Franck Comunale ◽  
Agusti Brugues ◽  
...  

Collective cell migration (CCM) is essential for organism development, wound healing, and metastatic transition, the primary cause of cancer-related death, and it involves cell–cell adhesion molecules of the cadherin family. Increased P-cadherin expression levels are correlated with tumor aggressiveness in carcinoma and aggressive sarcoma; however, how P-cadherin promotes tumor malignancy remains unknown. Here, using integrated cell biology and biophysical approaches, we determined that P-cadherin specifically induces polarization and CCM through an increase in the strength and anisotropy of mechanical forces. We show that this mechanical regulation is mediated by the P-cadherin/β-PIX/Cdc42 axis; P-cadherin specifically activates Cdc42 through β-PIX, which is specifically recruited at cell–cell contacts upon CCM. This mechanism of cell polarization and migration is absent in cells expressing E- or R-cadherin. Thus, we identify a specific role of P-cadherin through β-PIX–mediated Cdc42 activation in the regulation of cell polarity and force anisotropy that drives CCM.


2000 ◽  
Vol 151 (1) ◽  
pp. 187-198 ◽  
Author(s):  
Mark A. McNiven ◽  
Leung Kim ◽  
Eugene W. Krueger ◽  
James D. Orth ◽  
Hong Cao ◽  
...  

The dynamin family of large GTPases has been implicated in the formation of nascent vesicles in both the endocytic and secretory pathways. It is believed that dynamin interacts with a variety of cellular proteins to constrict membranes. The actin cytoskeleton has also been implicated in altering membrane shape and form during cell migration, endocytosis, and secretion and has been postulated to work synergistically with dynamin and coat proteins in several of these important processes. We have observed that the cytoplasmic distribution of dynamin changes dramatically in fibroblasts that have been stimulated to undergo migration with a motagen/hormone. In quiescent cells, dynamin 2 (Dyn 2) associates predominantly with clathrin-coated vesicles at the plasma membrane and the Golgi apparatus. Upon treatment with PDGF to induce cell migration, dynamin becomes markedly associated with membrane ruffles and lamellipodia. Biochemical and morphological studies using antibodies and GFP-tagged dynamin demonstrate an interaction with cortactin. Cortactin is an actin-binding protein that contains a well defined SH3 domain. Using a variety of biochemical methods we demonstrate that the cortactin–SH3 domain associates with the proline-rich domain (PRD) of dynamin. Functional studies that express wild-type and mutant forms of dynamin and/or cortactin in living cells support these in vitro observations and demonstrate that an increased expression of cortactin leads to a significant recruitment of endogenous or expressed dynamin into the cell ruffle. Further, expression of a cortactin protein lacking the interactive SH3 domain (CortΔSH3) significantly reduces dynamin localization to the ruffle. Accordingly, transfected cells expressing Dyn 2 lacking the PRD (Dyn 2(aa)ΔPRD) sequester little of this protein to the cortactin-rich ruffle. Interestingly, these mutant cells are viable, but display dramatic alterations in morphology. This change in shape appears to be due, in part, to a striking increase in the number of actin stress fibers. These findings provide the first demonstration that dynamin can interact with the actin cytoskeleton to regulate actin reorganization and subsequently cell shape.


Micromachines ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1015
Author(s):  
Mitsuru Sentoku ◽  
Hiromichi Hashimoto ◽  
Kento Iida ◽  
Masaharu Endo ◽  
Kenji Yasuda

Agarose photothermal microfabrication technology is one of the micropatterning techniques that has the advantage of simple and flexible real-time fabrication even during the cultivation of cells. To examine the ability and limitation of the agarose microstructures, we investigated the collective epithelial cell migration behavior in two-dimensional agarose confined structures. Agarose microchannels from 10 to 211 micrometer width were fabricated with a spot heating of a focused 1480 nm wavelength infrared laser to the thin agarose layer coated on the cultivation dish after the cells occupied the reservoir. The collective cell migration velocity maintained constant regardless of their extension distance, whereas the width dependency of those velocities was maximized around 30 micrometer width and decreased both in the narrower and wider microchannels. The single-cell tracking revealed that the decrease of velocity in the narrower width was caused by the apparent increase of aspect ratio of cell shape (up to 8.9). In contrast, the decrease in the wider channels was mainly caused by the increase of the random walk-like behavior of component cells. The results confirmed the advantages of this method: (1) flexible fabrication without any pre-designing, (2) modification even during cultivation, and (3) the cells were confined in the agarose geometry.


2017 ◽  
Author(s):  
Yasmin Sallak ◽  
Alba Yurani Torres ◽  
Hongyan Yin ◽  
Denise Montell

AbstractThe tyrosine kinase Src is over-expressed in numerous human cancers and is associated with poor prognosis. While Src has been extensively studied, its contributions to collective cell migration in vivo remain incompletely understood. Here we show that Src42A, but not Src64, is required for the specification and migration of the border cells in the Drosophila ovary, a well-developed and genetically tractable in vivo cell migration model. We found active Src42A enriched at border cell/nurse cell interfaces, where E-cadherin is less abundant, and depleted from border cell/border cell and border cell/polar cell junctions where E-cadherin is more stable, whereas total Src42A protein co-localizes with E-cadherin. Over-expression of wild type Src42A mislocalized Src activity and prevented border cell migration. Constitutively active or kinase dead forms of Src42A also impeded border cells. These findings establish border cells as a model for investigating the mechanisms of action of Src in cooperative, collective, cell-on-cell migration in vivo.


2016 ◽  
Vol 212 (7) ◽  
pp. 883-883 ◽  
Author(s):  
Anna Julia Squarr ◽  
Klaus Brinkmann ◽  
Baoyu Chen ◽  
Tim Steinbacher ◽  
Klaus Ebnet ◽  
...  

1998 ◽  
Vol 142 (2) ◽  
pp. 443-455 ◽  
Author(s):  
Mahasin A. Osman ◽  
Richard A. Cerione

The Rho-type GTPase Cdc42p has been implicated in diverse cellular functions including cell shape, cell motility, and cytokinesis, all of which involve the reorganization of the actin cytoskeleton. Targets of Cdc42p that interface the actin cytoskeleton are likely candidates for mediating cellular activities. In this report, we identify and characterize a yeast homologue for the mammalian IQGAP, a cytoskeletal target for Cdc42p. The yeast IQGAP homologue, designated Iqg1p, displays a two-hybrid interaction with activated Cdc42p and coimmunoprecipitates with actin filaments. Deletion of IQG1 results in a temperature-sensitive lethality and causes aberrant morphologies including elongated and round multinucleated cells. This together with its localization at the mother–bud neck, suggest that Iqg1p promotes budding and cytokinesis. At restrictive temperatures, the vacuoles of the mutant cells enlarge and vesicles accumulate in the bud. Interestingly, Iqg1p shows two-hybrid interactions with the ankyrin repeat–containing protein, Akr1p (Kao, L.-R., J. Peterson, J. Ruiru, L. Bender, and A. Bender. 1996. Mol. Cell. Biol. 16:168–178), which inhibits pheromone signaling and appears to promote cytokinesis and/or trafficking. We also show two-hybrid interactions between Iqg1p and Afr1p, a septin-binding protein involved in projection formation (Konopka, J.B., C. DeMattei, and C. Davis. 1995. Mol. Cell. Biol. 15:723–730). We propose that Iqg1p acts as a scaffold to recruit and localize a protein complex involved in actin-based cellular functions and thus mediates the regulatory effects of Cdc42p on the actin cytoskeleton.


Sign in / Sign up

Export Citation Format

Share Document