Integrins stimulate E-cadherin-mediated intercellular adhesion by regulating Src-kinase activation and actomyosin contractility

Abstract

Cadherins and integrins are major adhesion molecules regulating cell-cell and cell-matrix interactions. In vitro and in vivo studies have demonstrated the existence of crosstalk between integrins and cadherins in cell adhesion and motility. We used a dual pipette assay to measure the force required to separate E-cadherin-producing cell doublets and to investigate the role of integrin in regulating the strength of intercellular adhesion. A greater force was required to separate cell doublets bound to fibronectin or vitronectin-coated beads than for doublets bound to polylysine-coated beads. This effect depended on cell spreading and the duration of stimulation. Cells expressing type II cadherin-7 also responded to fibronectin stimulation to produce a higher intercellular adhesion. Establishment of cadherin-mediated adhesion needed ROCK, MLCK and myosin ATPase II activity. The regulation of intercellular adhesion strength by integrin stimulation required activation of Src family kinases, ROCK and actomyosin contractility. These findings highlight the importance and mechanisms of molecular crosstalk between cadherins and integrins in the control of cell plasticity during histogenesis and morphogenesis.

Endothelial basement membrane laminin 511 is essential for shear stress response

“…Inhibition of events downstream of β1‐integrin binding to laminin 511, including inhibition of focal adhesion kinase and Src kinase (Martinez‐Rico et al , 2010), also reduced the cell–cell adhesion strengths (Fig 5D). Similarly, inhibition of RhoA signalling, which has been implicated in both VE‐cadherin junctional localization and can also occur downstream of laminin–β1 integrin‐mediated interactions (Yamamoto et al , 2015), significantly reduced cell–cell adhesion strengths (Fig 5D).…”

“…Cells attached to beads were then permitted to bind to each other, and the strength required to detach two cells was measured (cell–cell adhesion strength). Previous studies have shown that adhesion complexes form in cells bound to the ECM‐coated beads (Martinez‐Rico et al , 2010). It was not possible to measure cell–cell adhesion strength after adhesion to laminin 411 due to the weak adhesion of HUAECs to this laminin isoform.…”

“…It is therefore likely that biochemical signals derived from endothelial adhesion to laminin 511 act downstream to regulate actin arrangements and thereby cortical stiffness and mechanotransduction processes (Hutcheson & Griffith, 1996; Tzima et al , 2001). Candidate downstream signalling molecules include RhoA, which has been implicated in force generation via β1‐integrins (Schiller et al , 2013) and shear responses (Jalali et al , 1998; Tzima et al , 2001), and Src kinase (Huveneers & Danen, 2009; Martinez‐Rico et al , 2010). …”

“…To determine whether cell–cell adhesion strengths were affected by endothelial cell adhesion to different laminins, a dual pipette assay was performed (Chu et al , 2004; Martinez‐Rico et al , 2010). Polystyrene macrobeads (15 μm, Polysciences, Inc.) were coated overnight at 4°C with 20 μM purified laminin 511, laminin 411 or laminin 111, added to a cell suspension of HUAECs in HEPES‐buffered cell culture medium at a ratio of 1:2 and incubated at 37°C, 5% CO 2 for 1 h to permit cell adhesion to the coated beads.…”

Deoxycholic acid promotes development of gastroesophageal reflux disease and Barrett's oesophagus by modulating integrin‐αv trafficking

“…Comprised of one α‐ and one β‐subunit, integrins bind with variable affinity and avidity to specific ECM proteins to provide anchorage and activate pro‐survival signalling 8. Intercellular adhesion mediated by integrins has also been described in squamous epithelium 16, 17, and the presence of integrin‐α 2 , α 3 , α 6 and α v has been demonstrated in oesophageal squamous epithelium 18, 19, 20. These adhesion molecules are constantly recycled in order to facilitate tissue remodelling in response to physiological stress.…”