scholarly journals p120 catenin associates with kinesin and facilitates the transport of cadherin–catenin complexes to intercellular junctions

2003 ◽  
Vol 163 (3) ◽  
pp. 547-557 ◽  
Author(s):  
Xinyu Chen ◽  
Shin-ichiro Kojima ◽  
Gary G. Borisy ◽  
Kathleen J. Green

p120 catenin (p120) is a component of adherens junctions and has been implicated in regulating cadherin-based cell adhesion as well as the activity of Rho small GTPases, but its exact roles in cell–cell adhesion are unclear. Using time-lapse imaging, we show that p120-GFP associates with vesicles and exhibits unidirectional movements along microtubules. Furthermore, p120 forms a complex with kinesin heavy chain through the p120 NH2-terminal head domain. Overexpression of p120, but not an NH2-terminal deletion mutant deficient in kinesin binding, recruits endogenous kinesin to N-cadherin. Disruption of the interaction between N-cadherin and p120, or the interaction between p120 and kinesin, leads to a delayed accumulation of N-cadherin at cell–cell contacts during calcium-initiated junction reassembly. Our analyses identify a novel role of p120 in promoting cell surface trafficking of cadherins via association and recruitment of kinesin.

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Jie Liu ◽  
Yanmei Qi ◽  
Shu-Chan Hsu ◽  
Siavash Saadat ◽  
Saum Rahimi ◽  
...  

Cellular repressor of E1A-stimulated genes 1 (CREG1) is a 24 kD glycoprotein essential for early embryonic development. Our immunofluorescence studies revealed that CREG1 is highly expressed at myocyte junctions in both embryonic and adult hearts. To explore it role in cardiomyogenesis, we employed gain- and loss-of-function analyses demonstrating that CREG1 is required for the differentiation of mouse embryonic stem (ES) cell into cohesive myocardium-like structures. Chimeric cultures of wild-type and CREG1 knockout ES cells expressing cardiac-specific reporters showed that the cardiomyogenic effect of CREG1 is cell autonomous. Furthermore, we identified a novel interaction between CREG1 and Sec8 of the exocyst complex, which tethers vesicles to the plasma membrane. Mutations of the amino acid residues D141 and P142 to alanine in CREG1 abolished its binding to Sec8. To address the role of the CREG1-Sec8 interaction in cardiomyogenesis, we rescued CREG1 knockout ES cells with wild-type and Sec8-binding mutant CREG1 and showed that CREG1 binding to Sec8 promotes cardiomyocyte differentiation and cohesion. Mechanistically, CREG1, Sec8 and N-cadherin all localize at cell-cell adhesion sites. CREG1 overexpression enhances the assembly of adherens and gap junctions. By contrast, its knockout inhibits the Sec8-N-cadherin interaction and induces their degradation. Finally, shRNA-mediated knockdown of Sec8 leads to cardiomyogenic defects similar to CREG1 knockout. These results suggest that the CREG1 binding to Sec8 enhances the assembly of intercellular junctions and promotes cardiomyogenesis.


2019 ◽  
Vol 244 (15) ◽  
pp. 1303-1312 ◽  
Author(s):  
Beata Machnicka ◽  
Renata Grochowalska ◽  
Dżamila M Bogusławska ◽  
Aleksander F Sikorski

Spectrins are proteins that are responsible for many aspects of cell function and adaptation to changing environments. Primarily the spectrin-based membrane skeleton maintains cell membrane integrity and its mechanical properties, together with the cytoskeletal network a support cell shape. The occurrence of a variety of spectrin isoforms in diverse cellular environments indicates that it is a multifunctional protein involved in numerous physiological pathways. Participation of spectrin in cell–cell and cell–extracellular matrix adhesion and formation of dynamic plasma membrane protrusions and associated signaling events is a subject of interest for researchers in the fields of cell biology and molecular medicine. In this mini-review, we focus on data concerning the role of spectrins in cell surface activities such as adhesion, cell–cell contact, and invadosome formation. We discuss data on different adhesion proteins that directly or indirectly interact with spectrin repeats. New findings support the involvement of spectrin in cell adhesion and spreading, formation of lamellipodia, and also the participation in morphogenetic processes, such as eye development, oogenesis, and angiogenesis. Here, we review the role of spectrin in cell adhesion and cell–cell contact.Impact statementThis article reviews properties of spectrins as a group of proteins involved in cell surface activities such as, adhesion and cell–cell contact, and their contribution to morphogenesis. We show a new area of research and discuss the involvement of spectrin in regulation of cell–cell contact leading to immunological synapse formation and in shaping synapse architecture during myoblast fusion. Data indicate involvement of spectrins in adhesion and cell–cell or cell–extracellular matrix interactions and therefore in signaling pathways. There is evidence of spectrin’s contribution to the processes of morphogenesis which are connected to its interactions with adhesion molecules, membrane proteins (and perhaps lipids), and actin. Our aim was to highlight the essential role of spectrin in cell–cell contact and cell adhesion.


1997 ◽  
Vol 137 (6) ◽  
pp. 1421-1431 ◽  
Author(s):  
Vania M.M. Braga ◽  
Laura M. Machesky ◽  
Alan Hall ◽  
Neil A. Hotchin

Cadherins are calcium-dependent cell–cell adhesion molecules that require the interaction of the cytoplasmic tail with the actin cytoskeleton for adhesive activity. Because of the functional relationship between cadherin receptors and actin filament organization, we investigated whether members of the Rho family of small GTPases are necessary for cadherin adhesion. In fibroblasts, the Rho family members Rho and Rac regulate actin polymerization to produce stress fibers and lamellipodia, respectively. In epithelial cells, we demonstrate that Rho and Rac are required for the establishment of cadherin-mediated cell–cell adhesion and the actin reorganization necessary to stabilize the receptors at sites of intercellular junctions. Blocking endogenous Rho or Rac selectively removed cadherin complexes from junctions induced for up to 3 h, while desmosomes were not perturbed. In addition, withdrawal of cadherins from intercellular junctions temporally precedes the removal of CD44 and integrins, other microfilament-associated receptors. Our data showed that the concerted action of Rho and Rac modulate the establishment of cadherin adhesion: a constitutively active form of Rac was not sufficient to stabilize cadherindependent cell–cell contacts when endogenous Rho was inhibited. Upon induction of calcium-dependent intercellular adhesion, there was a rapid accumulation of actin at sites of cell–cell contacts, which was prevented by blocking cadherin function, Rho or Rac activity. However, if cadherin complexes are clustered by specific antibodies attached to beads, actin recruitment to the receptors was perturbed by inhibiting Rac but not Rho. Our results provide new insights into the role of the small GTPases in the cadherin-dependent cell– cell contact formation and the remodelling of actin filaments in epithelial cells.


Author(s):  
Saswati Banerjee ◽  
Gopal Majumder

AbstractMany studies have implicated cell-surface lectins in heterologous cell-cell adhesion, but little is known about the participation of lectins in cellular adhesion in homologous cells. Here, we show the development of a cell model for investigating the direct role of a cell-surface lectin in homologous cell-cell adhesion. Parenchymal cells were isolated from caprine liver using a perfusion buffer, and dispersed in a chemically defined modified Ringer’s solution. These cells undergo autoagglutination in the presence of Ca2+. The autoagglutinated cells can be dissociated specifically with D-galactose (50 mM), which also inhibits the liver cell autoagglutination event. The blood serum protein fetuin has no effect on liver cell autoagglutination, whereas desialylated fetuin (100 μM), with its terminal D-galactose residue, showed a high affinity for blocking the autoagglutination event. The data demonstrates the occurrence of a Ca2+-dependent D-galactose-specific lectin and a lectin receptor on the parenchymal cells. Furthermore, it shows that the observed autoagglutination event is caused by the interaction of the cell-surface lectin with its receptor on the neighbouring homologous cells. The data supports the view that homologous cell-cell contact in mammalian tissues is triggered by such lectin-receptor interaction and that the previously reported cell-surface adhesive proteins serve as a secondary force to strengthen cell adhesion. This cell model could be extremely useful for investigating the direct role of cell-surface lectin and its receptor in homologous cell adhesion in a variety of tissues under normal and pathological conditions.


2021 ◽  
Vol 15 (1) ◽  
pp. 1-17
Author(s):  
Sarah Alsharif ◽  
Pooja Sharma ◽  
Karina Bursch ◽  
Rachel Milliken ◽  
Van Lam ◽  
...  

2002 ◽  
Vol 115 (9) ◽  
pp. 1837-1846 ◽  
Author(s):  
Sandra van Wetering ◽  
Jaap D. van Buul ◽  
Safira Quik ◽  
Frederik P. J. Mul ◽  
Eloise C. Anthony ◽  
...  

The integrity of the endothelium is dependent on cell-cell adhesion, which is mediated by vascular-endothelial (VE)-cadherin. Proper VE-cadherin-mediated homotypic adhesion is, in turn, dependent on the connection between VE-cadherin and the cortical actin cytoskeleton. Rho-like small GTPases are key molecular switches that control cytoskeletal dynamics and cadherin function in epithelial as well as endothelial cells. We show here that a cell-penetrating, constitutively active form of Rac (Tat-RacV12) induces a rapid loss of VE-cadherin-mediated cell-cell adhesion in endothelial cells from primary human umbilical veins (pHUVEC). This effect is accompanied by the formation of actin stress fibers and is dependent on Rho activity. However,transduction of pHUVEC with Tat-RhoV14, which induces pronounced stress fiber and focal adhesion formation, did not result in a redistribution of VE-cadherin or an overall loss of cell-cell adhesion. In line with this observation, endothelial permeability was more efficiently increased by Tat-RacV12 than by Tat-RhoV14. The loss of cell-cell adhesion, which is induced by Tat-RacV12, occurred in parallel to and was dependent upon the intracellular production of reactive oxygen species (ROS). Moreover, Tat-RacV12 induced an increase in tyrosine phosphorylation of a component the VE-cadherin-catenin complex, which was identified as α-catenin. The functional relevance of this signaling pathway was further underscored by the observation that endothelial cell migration, which requires a transient reduction of cell-cell adhesion, was blocked when signaling through ROS was inhibited. In conclusion, Rac-mediated production of ROS represents a previously unrecognized means of regulating VE-cadherin function and may play an important role in the (patho)physiology associated with inflammation and endothelial damage as well as with endothelial cell migration and angiogenesis.


2007 ◽  
Vol 178 (2) ◽  
pp. 323-335 ◽  
Author(s):  
Lene N. Nejsum ◽  
W. James Nelson

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.


2008 ◽  
Vol 13 (8) ◽  
pp. 797-805 ◽  
Author(s):  
Kaori Kuramitsu ◽  
Wataru Ikeda ◽  
Naoya Inoue ◽  
Yoshiyuki Tamaru ◽  
Yoshimi Takai

Sign in / Sign up

Export Citation Format

Share Document