Cell division orientation is coupled to cell–cell adhesion by the E-cadherin/LGN complex

Mechanical cues are sensed and transduced by cell adhesion complexes to regulate diverse cell behaviors. Extracellular matrix (ECM) rigidity sensing by integrin adhesions has been well studied, but rigidity sensing by cadherins during cell adhesion is largely unexplored. Using mechanically tunable polyacrylamide (PA) gels functionalized with the extracellular domain of E-cadherin (Ecad-Fc), we showed that E-cadherin–dependent epithelial cell adhesion was sensitive to changes in PA gel elastic modulus that produced striking differences in cell morphology, actin organization, and membrane dynamics. Traction force microscopy (TFM) revealed that cells produced the greatest tractions at the cell periphery, where distinct types of actin-based membrane protrusions formed. Cells responded to substrate rigidity by reorganizing the distribution and size of high-traction-stress regions at the cell periphery. Differences in adhesion and protrusion dynamics were mediated by balancing the activities of specific signaling molecules. Cell adhesion to a 30-kPa Ecad-Fc PA gel required Cdc42- and formin-dependent filopodia formation, whereas adhesion to a 60-kPa Ecad-Fc PA gel induced Arp2/3-dependent lamellipodial protrusions. A quantitative 3D cell–cell adhesion assay and live cell imaging of cell–cell contact formation revealed that inhibition of Cdc42, formin, and Arp2/3 activities blocked the initiation, but not the maintenance of established cell–cell adhesions. These results indicate that the same signaling molecules activated by E-cadherin rigidity sensing on PA gels contribute to actin organization and membrane dynamics during cell–cell adhesion. We hypothesize that a transition in the stiffness of E-cadherin homotypic interactions regulates actin and membrane dynamics during initial stages of cell–cell adhesion.

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Purification of a 92-kDa cytoplasmic protein tightly associated with the cell-cell adhesion molecule E-cadherin (uvomorulin)

Journal of Biological Chemistry ◽

10.1016/s0021-9258(20)64353-8 ◽

1991 ◽

Vol 266 (7) ◽

pp. 4514-4520

Author(s):

P D McCrea ◽

B M Gumbiner

Keyword(s):

Cell Adhesion ◽

Adhesion Molecule ◽

Cell Adhesion Molecule ◽

Cytoplasmic Protein ◽

E Cadherin ◽

Cell Cell

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A molecular mechanism directly linking E-cadherin adhesion to initiation of epithelial cell surface polarity

The Journal of Cell Biology ◽

10.1083/jcb.200705094 ◽

2007 ◽

Vol 178 (2) ◽

pp. 323-335 ◽

Cited By ~ 109

Author(s):

Lene N. Nejsum ◽

W. James Nelson

Keyword(s):

Cell Adhesion ◽

Epithelial Cell ◽

Cell Surface ◽

Basolateral Membrane ◽

Surface Polarity ◽

Cell Contacts ◽

Protein Receptors ◽

Epithelial Cell Surface ◽

E Cadherin ◽

Cell Cell

Mechanisms involved in maintaining plasma membrane domains in fully polarized epithelial cells are known, but when and how directed protein sorting and trafficking occur to initiate cell surface polarity are not. We tested whether establishment of the basolateral membrane domain and E-cadherin–mediated epithelial cell–cell adhesion are mechanistically linked. We show that the basolateral membrane aquaporin (AQP)-3, but not the equivalent apical membrane AQP5, is delivered in post-Golgi structures directly to forming cell–cell contacts where it co-accumulates precisely with E-cadherin. Functional disruption of individual components of a putative lateral targeting patch (e.g., microtubules, the exocyst, and soluble N-ethylmaleimide–sensitive factor attachment protein receptors) did not inhibit cell–cell adhesion or colocalization of the other components with E-cadherin, but each blocked AQP3 delivery to forming cell–cell contacts. Thus, components of the lateral targeting patch localize independently of each other to cell–cell contacts but collectively function as a holocomplex to specify basolateral vesicle delivery to nascent cell–cell contacts and immediately initiate cell surface polarity.

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Reevaluating αE-catenin monomer and homodimer functions by characterizing E-cadherin/αE-catenin chimeras

The Journal of Cell Biology ◽

10.1083/jcb.201411080 ◽

2015 ◽

Vol 210 (7) ◽

pp. 1065-1074 ◽

Cited By ~ 18

Author(s):

Julie M. Bianchini ◽

Khameeka N. Kitt ◽

Martijn Gloerich ◽

Sabine Pokutta ◽

William I. Weis ◽

...

Keyword(s):

Cell Adhesion ◽

Intercellular Adhesion ◽

Dependent Cell ◽

In Cells ◽

E Cadherin ◽

Cell Cell

As part of the E-cadherin–β-catenin–αE-catenin complex (CCC), mammalian αE-catenin binds F-actin weakly in the absence of force, whereas cytosolic αE-catenin forms a homodimer that interacts more strongly with F-actin. It has been concluded that cytosolic αE-catenin homodimer is not important for intercellular adhesion because E-cadherin/αE-catenin chimeras thought to mimic the CCC are sufficient to induce cell–cell adhesion. We show that, unlike αE-catenin in the CCC, these chimeras homodimerize, bind F-actin strongly, and inhibit the Arp2/3 complex, all of which are properties of the αE-catenin homodimer. To more accurately mimic the junctional CCC, we designed a constitutively monomeric chimera, and show that E-cadherin–dependent cell adhesion is weaker in cells expressing this chimera compared with cells in which αE-catenin homodimers are present. Our results demonstrate that E-cadherin/αE-catenin chimeras used previously do not mimic αE-catenin in the native CCC, and imply that both CCC-bound monomer and cytosolic homodimer αE-catenin are required for strong cell–cell adhesion.

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