scholarly journals EphA2 Engages Git1 to Suppress Arf6 Activity Modulating Epithelial Cell–Cell Contacts

2009 ◽  
Vol 20 (7) ◽  
pp. 1949-1959 ◽  
Author(s):  
Koichi Miura ◽  
Jin-Min Nam ◽  
Chie Kojima ◽  
Naoki Mochizuki ◽  
Hisataka Sabe
Keyword(s):  
Ion Concentration ◽  
Cell Contact ◽  
Interacting Protein ◽  
Cell Contacts ◽  
Extracellular Signal ◽  
Src Homology ◽  
Src Homology 2 Domain ◽  
Mediate Cell ◽  
E Cadherin ◽  
Cell Cell

ADP-ribosylation factor (Arf) 6 activity is crucially involved in the regulation of E-cadherin–based cell–cell adhesions. Erythropoietin-producing hepatocellular carcinoma (Eph)-family receptors recognize ligands, namely, ephrins, anchored to the membrane of apposing cells, and they mediate cell–cell contact-dependent events. Here, we found that Arf6 activity is down-regulated in Madin-Darby canine kidney cells, which is dependent on cell density and calcium ion concentration, and we provide evidence of a novel signaling pathway by which ligand-activated EphA2 suppresses Arf6 activity. This EphA2-mediated suppression of Arf6 activity was linked to the induction of cell compaction and polarization, but it was independent of the down-regulation of extracellular signal-regulated kinase 1/2 kinase activity. We show that G protein-coupled receptor kinase-interacting protein (Git) 1 and noncatalytic region of tyrosine kinase (Nck) 1 are involved in this pathway, in which ligand-activated EphA2, via its phosphorylated Tyr594, binds to the Src homology 2 domain of Nck1, and then via its Src homology 3 domain binds to the synaptic localizing domain of Git1 to suppress Arf6 activity. We propose a positive feedback loop in which E-cadherin–based cell–cell contacts enhance EphA-ephrinA signaling, which in turn down-regulates Arf6 activity to enhance E-cadherin–based cell–cell contacts as well as the apical-basal polarization of epithelial cells.

scholarly journals The formation of ordered nanoclusters controls cadherin anchoring to actin and cell–cell contact fluidity

2015 ◽  
Vol 210 (2) ◽  
pp. 333-346 ◽  
Author(s):  
Pierre-Olivier Strale ◽  
Laurence Duchesne ◽  
Grégoire Peyret ◽  
Lorraine Montel ◽  
Thao Nguyen ◽  
...  
Keyword(s):  
Adherens Junction ◽  
Intercellular Junctions ◽  
Cell Contact ◽  
Collective Cell Migration ◽  
Contact Stability ◽  
Junction Formation ◽  
Mediate Cell ◽  
The Stability ◽  
E Cadherin ◽  
Cell Cell

Oligomerization of cadherins could provide the stability to ensure tissue cohesion. Cadherins mediate cell–cell adhesion by forming trans-interactions. They form cis-interactions whose role could be essential to stabilize intercellular junctions by shifting cadherin clusters from a fluid to an ordered phase. However, no evidence has been provided so far for cadherin oligomerization in cellulo and for its impact on cell–cell contact stability. Visualizing single cadherins within cell membrane at a nanometric resolution, we show that E-cadherins arrange in ordered clusters, providing the first demonstration of the existence of oligomeric cadherins at cell–cell contacts. Studying the consequences of the disruption of the cis-interface, we show that it is not essential for adherens junction formation. Its disruption, however, increased the mobility of junctional E-cadherin. This destabilization strongly affected E-cadherin anchoring to actin and cell–cell rearrangement during collective cell migration, indicating that the formation of oligomeric clusters controls the anchoring of cadherin to actin and cell–cell contact fluidity.

scholarly journals Recycling of E-Cadherin

1999 ◽  
Vol 146 (1) ◽  
pp. 219-232 ◽  
Author(s):  
Tam Luan Le ◽  
Alpha S. Yap ◽  
Jennifer L. Stow
Keyword(s):  
Cell Surface ◽  
Cell Junctions ◽  
Cell Contact ◽  
Epithelial Polarity ◽  
Cell Contacts ◽  
Epithelial Development ◽  
The Reformation ◽  
Intracellular Compartments ◽  
E Cadherin ◽  
Cell Cell

E-Cadherin plays critical roles in many aspects of cell adhesion, epithelial development, and the establishment and maintenance of epithelial polarity. The fate of E-cadherin once it is delivered to the basolateral cell surface, and the mechanisms which govern its participation in adherens junctions, are not well understood. Using surface biotinylation and recycling assays, we observed that some of the cell surface E-cadherin is actively internalized and is then recycled back to the plasma membrane. The pool of E-cadherin undergoing endocytosis and recycling was markedly increased in cells without stable cell-cell contacts, i.e., in preconfluent cells and after cell contacts were disrupted by depletion of extracellular Ca2+, suggesting that endocytic trafficking of E-cadherin is regulated by cell-cell contact. The reformation of cell junctions after replacement of Ca2+ was then found to be inhibited when recycling of endocytosed E-cadherin was disrupted by bafilomycin treatment. The endocytosis and recycling of E-cadherin and of the transferrin receptor were similarly inhibited by potassium depletion and by bafilomycin treatment, and both proteins were accumulated in intracellular compartments by an 18°C temperature block, suggesting that endocytosis may occur via a clathrin-mediated pathway. We conclude that a pool of surface E-cadherin is constantly trafficked through an endocytic, recycling pathway and that this may provide a mechanism for regulating the availability of E-cadherin for junction formation in development, tissue remodeling, and tumorigenesis.

scholarly journals Quantitative analysis of cadherin-catenin-actin reorganization during development of cell-cell adhesion.

1996 ◽  
Vol 135 (6) ◽  
pp. 1899-1911 ◽  
Author(s):  
C L Adams ◽  
W J Nelson ◽  
S J Smith
Keyword(s):  
Cell Adhesion ◽  
Time Lapse ◽  
Cell Contact ◽  
Beta Catenin ◽  
Actin Reorganization ◽  
Cell Contacts ◽  
Spatial Ordering ◽  
Triton X ◽  
E Cadherin ◽  
Cell Cell

Epithelial cell-cell adhesion requires interactions between opposing extracellular domains of E-cadherin, and among the cytoplasmic domain of E-cadherin, catenins, and actin cytoskeleton. Little is known about how the cadherin-catenin-actin complex is assembled upon cell-cell contact, or how these complexes initiate and strengthen adhesion. We have used time-lapse differential interference contrast (DIC) imaging to observe the development of cell-cell contacts, and quantitative retrospective immunocytochemistry to measure recruitment of proteins to those contacts. We show that E-cadherin, alpha-catenin, and beta-catenin, but not plakoglobin, coassemble into Triton X-100 insoluble (TX-insoluble) structures at cell-cell contacts with kinetics similar to those for strengthening of E-cadherin-mediated cell adhesion (Angres, B., A. Barth, and W.J. Nelson. 1996. J. Cell Biol. 134:549-557). TX-insoluble E-cadherin, alpha-catenin, and beta-catenin colocalize along cell-cell contacts in spatially discrete micro-domains which we designate "puncta," and the relative amounts of each protein in each punctum increase proportionally. As the length of the contact increases, the number of puncta increases proportionally along the contact and each punctum is associated with a bundle of actin filaments. These results indicate that localized clustering of E-cadherin/catenin complexes into puncta and their association with actin is involved in initiating cell contacts. Subsequently, the spatial ordering of additional puncta along the contact may be involved in zippering membranes together, resulting in rapid strengthening of adhesion.

scholarly journals Loss of E-Cadherin–mediated Cell–Cell Contacts Activates a Novel Mechanism for Up-Regulation of the Proto-Oncogene c-Jun

2009 ◽  
Vol 20 (7) ◽  
pp. 2121-2129 ◽  
Author(s):  
Revital Knirsh ◽  
Iris Ben-Dror ◽  
Barbara Spangler ◽  
Gideon D. Matthews ◽  
Silke Kuphal ◽  
...  
Keyword(s):  
Cell Separation ◽  
Tumor Promotion ◽  
Mitogen Activated Protein Kinase ◽  
Cell Contact ◽  
Activator Protein 1 ◽  
Cell Contacts ◽  
Mitogen Activated Protein ◽  
Stimulation Of ◽  
E Cadherin ◽  
Cell Cell

Loss of E-cadherin–mediated cell–cell contacts can elicit a signaling pathway that leads to acquisition of an invasive phenotype. Here, we show that at the receiving end of this pathway is the proto-oncogene c-Jun, a member of the activator protein-1 family of transcription factors that play a key role in stimulation of cell proliferation and tumor promotion. Cell separation or abrogation of E-cadherin–mediated cell–cell contacts both cause a dramatic increase in accumulation of the c-Jun protein. Unlike growth factors that enhance the expression of c-Jun by activating the transcription of the c-jun gene, the cell contact-dependent increase in c-Jun accumulation is not accompanied by a corresponding increase in c-Jun mRNA or c-Jun protein stability but rather in the translatability of the c-Jun transcript. Consistently, the increase in c-Jun accumulation is not dependent on activation of the mitogen-activated protein kinase or β-catenin pathways but is mediated by signals triggered by the restructured cytoskeleton. Depolymerization of the cytoskeleton can mimic the effect of cell separation and cause a dramatic increase in c-Jun accumulation, whereas Taxol inhibits the cell contact-dependent increase. This novel mechanism of c-Jun regulation seems to underlie the robust overexpression of c-Jun in tumor cells of patients with colon carcinoma.

scholarly journals Cortical actin flow activates an alpha-catenin clutch to assemble adherens junctions

2021 ◽  
Author(s):  
Ivar Noordstra ◽  
Mario Diez Hermoso ◽  
Lilian Schimmel ◽  
Alexis Bonfim-Melo ◽  
Joseph Mathew Kalappurakkal ◽  
...  
Keyword(s):  
Adherens Junctions ◽  
Actin Binding ◽  
Cell Contact ◽  
Cortical Actin ◽  
Bond Behaviour ◽  
Catch Bond ◽  
Actin Cortex ◽  
Mediate Cell ◽  
E Cadherin ◽  
Cell Cell

Adherens junctions (AJs) fundamentally mediate cell-cell adhesion, yet the mechanisms that determine where or when AJs assemble are not understood. Here we reveal a mechanosensitive clutch that initiates AJ assembly. Before cell-cell contact, alpha-catenin couples surface E-cadherin complexes to retrograde flow of the actin cortex. Cortical flows with opposed orientations persist after contact, applying tension to alpha-catenin within trans-ligated cadherin complexes. Tension unfolds the alpha-catenin actin-binding domain (ABD), which is expected to mediate a catch bond with F-actin. However, catch bond behaviour is not sufficient for AJ assembly in a molecular clutch model. Instead, it is also necessary for the activated ABD to promote cis-clustering of E-cadherin molecules by bundling F-actin. Thus, this alpha-catenin clutch transduces the mechanical signal of cortical flow to assemble AJs.

scholarly journals Remodeling the cell surface distribution of membrane proteins during the development of epithelial cell polarity.

1992 ◽  
Vol 116 (4) ◽  
pp. 889-899 ◽  
Author(s):  
D A Wollner ◽  
K A Krzeminski ◽  
W J Nelson
Keyword(s):  
Epithelial Cell ◽  
Membrane Proteins ◽  
Cell Surface ◽  
Mdck Cells ◽  
Apical Cell ◽  
Cell Contact ◽  
Surface Polarity ◽  
Lateral Membrane ◽  
E Cadherin ◽  
Cell Cell

The development of polarized epithelial cells from unpolarized precursor cells follows induction of cell-cell contacts and requires resorting of proteins into different membrane domains. We show that in MDCK cells the distributions of two membrane proteins, Dg-1 and E-cadherin, become restricted to the basal-lateral membrane domain within 8 h of cell-cell contact. During this time, however, 60-80% of newly synthesized Dg-1 and E-cadherin is delivered directly to the forming apical membrane and then rapidly removed, while the remainder is delivered to the basal-lateral membrane and has a longer residence time. Direct delivery of greater than 95% of these proteins from the Golgi complex to the basal-lateral membrane occurs greater than 48 h later. In contrast, we show that two apical proteins are efficiently delivered and restricted to the apical cell surface within 2 h after cell-cell contact. These results provide insight into mechanisms involved in the development of epithelial cell surface polarity, and the establishment of protein sorting pathways in polarized cells.

scholarly journals Changes in E-cadherin rigidity sensing regulate cell adhesion

2017 ◽  
Vol 114 (29) ◽  
pp. E5835-E5844 ◽  
Author(s):  
Caitlin Collins ◽  
Aleksandra K. Denisin ◽  
Beth L. Pruitt ◽  
W. James Nelson
Keyword(s):  
Cell Adhesion ◽  
Signaling Molecules ◽  
Membrane Dynamics ◽  
Cell Contact ◽  
Adhesion Assay ◽  
Cell Periphery ◽  
Actin Organization ◽  
Rigidity Sensing ◽  
E Cadherin ◽  
Cell Cell

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.

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

2007 ◽  
Vol 178 (2) ◽  
pp. 323-335 ◽  
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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