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Integrin-dependent actomyosin contraction regulates epithelial cell scattering.

de Rooij J, Kerstens A, Danuser G, Schwartz MA, Waterman-Storer CM - J. Cell Biol. (2005)

Bottom Line: Scattering is enhanced on collagen and fibronectin, as compared with laminin1, suggesting possible cross talk between integrins and cell-cell junctions.Rigid substrates that produce high traction forces promoted scattering, in comparison to more compliant substrates.We conclude that integrin-dependent actomyosin traction force mediates the disruption of cell-cell adhesion during epithelial cell scattering.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.

ABSTRACT
The scattering of Madin-Darby canine kidney cells in vitro mimics key aspects of epithelial-mesenchymal transitions during development, carcinoma cell invasion, and metastasis. Scattering is induced by hepatocyte growth factor (HGF) and is thought to involve disruption of cadherin-dependent cell-cell junctions. Scattering is enhanced on collagen and fibronectin, as compared with laminin1, suggesting possible cross talk between integrins and cell-cell junctions. We show that HGF does not trigger any detectable decrease in E-cadherin function, but increases integrin-mediated adhesion. Time-lapse imaging suggests that tension on cell-cell junctions may disrupt cell-cell adhesion. Varying the density and type of extracellular matrix proteins shows that scattering correlates with stronger integrin adhesion and increased phosphorylation of the myosin regulatory light chain. To directly test the role of integrin-dependent traction forces, substrate compliance was varied. Rigid substrates that produce high traction forces promoted scattering, in comparison to more compliant substrates. We conclude that integrin-dependent actomyosin traction force mediates the disruption of cell-cell adhesion during epithelial cell scattering.

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Scattering on increasing ECM correlates with adhesion strength, not migration velocity. (A and B) MDCK cells plated on different amounts of ECM, as in Fig. 3, were allowed to adhere in the presence or absence of HGF for 1 h. Unbound cells were removed and bound cells were quantified. Data are means ± SD; n = 3. Results show that adhesion on all matrices is saturable, is in the order Cn > Fn > Ln1, and is increased by HGF. (C) The average velocity of single cells on saturating concentrations of each ECM was determined from the same data used for Fig. 3 B. For all matrices, HGF induces an increase in cell migration, similar in timing and magnitude. (D) Cell velocity exhibits a classic biphasic response to increasing concentrations of all matrices. The average single cell velocity between 12–16 h after HGF was calculated for increasing ECM concentrations. At this interval, velocity had reached its maximum in all cases. Data are means ± SEM; at least 30 single cells per condition were included in this measurement.
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fig4: Scattering on increasing ECM correlates with adhesion strength, not migration velocity. (A and B) MDCK cells plated on different amounts of ECM, as in Fig. 3, were allowed to adhere in the presence or absence of HGF for 1 h. Unbound cells were removed and bound cells were quantified. Data are means ± SD; n = 3. Results show that adhesion on all matrices is saturable, is in the order Cn > Fn > Ln1, and is increased by HGF. (C) The average velocity of single cells on saturating concentrations of each ECM was determined from the same data used for Fig. 3 B. For all matrices, HGF induces an increase in cell migration, similar in timing and magnitude. (D) Cell velocity exhibits a classic biphasic response to increasing concentrations of all matrices. The average single cell velocity between 12–16 h after HGF was calculated for increasing ECM concentrations. At this interval, velocity had reached its maximum in all cases. Data are means ± SEM; at least 30 single cells per condition were included in this measurement.

Mentions: One explanation for the ECM dependence of cell scattering is that stronger substrate adhesion may promote disruption of cell–cell junctions. To investigate the relationship between ECM concentration and cell adhesion, we measured MDCK cell adhesion to the same 48-well plates used in the live-cell scattering assays coated with a range of ECM protein concentrations. 1 h after plating, unbound cells were washed from the wells and bound cells were quantified, as before. As expected, adhesion was dose dependent and saturable for each ECM protein, with Cn inducing the most efficient cell adhesion, followed by Fn and Ln1 (Fig. 4 A). Comparing these adhesion curves with Fig. 3 (A–C) shows that increasing adhesion, as measured in this assay, correlates well with the efficiency of scattering. To determine whether the different scattering efficiencies observed for cells plated on different substrates could be due to integrin-specific effects of HGF on adhesive activity, we compared adhesion in the presence or absence of HGF. Adhesion was increased by HGF to a similar extent on all substrates (Fig. 4 B), showing that, like cadherin-mediated adhesion (Fig. 1 C), HGF promotes adhesion to ECM irrespective of the specific integrins engaged.


Integrin-dependent actomyosin contraction regulates epithelial cell scattering.

de Rooij J, Kerstens A, Danuser G, Schwartz MA, Waterman-Storer CM - J. Cell Biol. (2005)

Scattering on increasing ECM correlates with adhesion strength, not migration velocity. (A and B) MDCK cells plated on different amounts of ECM, as in Fig. 3, were allowed to adhere in the presence or absence of HGF for 1 h. Unbound cells were removed and bound cells were quantified. Data are means ± SD; n = 3. Results show that adhesion on all matrices is saturable, is in the order Cn > Fn > Ln1, and is increased by HGF. (C) The average velocity of single cells on saturating concentrations of each ECM was determined from the same data used for Fig. 3 B. For all matrices, HGF induces an increase in cell migration, similar in timing and magnitude. (D) Cell velocity exhibits a classic biphasic response to increasing concentrations of all matrices. The average single cell velocity between 12–16 h after HGF was calculated for increasing ECM concentrations. At this interval, velocity had reached its maximum in all cases. Data are means ± SEM; at least 30 single cells per condition were included in this measurement.
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Related In: Results  -  Collection

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fig4: Scattering on increasing ECM correlates with adhesion strength, not migration velocity. (A and B) MDCK cells plated on different amounts of ECM, as in Fig. 3, were allowed to adhere in the presence or absence of HGF for 1 h. Unbound cells were removed and bound cells were quantified. Data are means ± SD; n = 3. Results show that adhesion on all matrices is saturable, is in the order Cn > Fn > Ln1, and is increased by HGF. (C) The average velocity of single cells on saturating concentrations of each ECM was determined from the same data used for Fig. 3 B. For all matrices, HGF induces an increase in cell migration, similar in timing and magnitude. (D) Cell velocity exhibits a classic biphasic response to increasing concentrations of all matrices. The average single cell velocity between 12–16 h after HGF was calculated for increasing ECM concentrations. At this interval, velocity had reached its maximum in all cases. Data are means ± SEM; at least 30 single cells per condition were included in this measurement.
Mentions: One explanation for the ECM dependence of cell scattering is that stronger substrate adhesion may promote disruption of cell–cell junctions. To investigate the relationship between ECM concentration and cell adhesion, we measured MDCK cell adhesion to the same 48-well plates used in the live-cell scattering assays coated with a range of ECM protein concentrations. 1 h after plating, unbound cells were washed from the wells and bound cells were quantified, as before. As expected, adhesion was dose dependent and saturable for each ECM protein, with Cn inducing the most efficient cell adhesion, followed by Fn and Ln1 (Fig. 4 A). Comparing these adhesion curves with Fig. 3 (A–C) shows that increasing adhesion, as measured in this assay, correlates well with the efficiency of scattering. To determine whether the different scattering efficiencies observed for cells plated on different substrates could be due to integrin-specific effects of HGF on adhesive activity, we compared adhesion in the presence or absence of HGF. Adhesion was increased by HGF to a similar extent on all substrates (Fig. 4 B), showing that, like cadherin-mediated adhesion (Fig. 1 C), HGF promotes adhesion to ECM irrespective of the specific integrins engaged.

Bottom Line: Scattering is enhanced on collagen and fibronectin, as compared with laminin1, suggesting possible cross talk between integrins and cell-cell junctions.Rigid substrates that produce high traction forces promoted scattering, in comparison to more compliant substrates.We conclude that integrin-dependent actomyosin traction force mediates the disruption of cell-cell adhesion during epithelial cell scattering.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.

ABSTRACT
The scattering of Madin-Darby canine kidney cells in vitro mimics key aspects of epithelial-mesenchymal transitions during development, carcinoma cell invasion, and metastasis. Scattering is induced by hepatocyte growth factor (HGF) and is thought to involve disruption of cadherin-dependent cell-cell junctions. Scattering is enhanced on collagen and fibronectin, as compared with laminin1, suggesting possible cross talk between integrins and cell-cell junctions. We show that HGF does not trigger any detectable decrease in E-cadherin function, but increases integrin-mediated adhesion. Time-lapse imaging suggests that tension on cell-cell junctions may disrupt cell-cell adhesion. Varying the density and type of extracellular matrix proteins shows that scattering correlates with stronger integrin adhesion and increased phosphorylation of the myosin regulatory light chain. To directly test the role of integrin-dependent traction forces, substrate compliance was varied. Rigid substrates that produce high traction forces promoted scattering, in comparison to more compliant substrates. We conclude that integrin-dependent actomyosin traction force mediates the disruption of cell-cell adhesion during epithelial cell scattering.

Show MeSH
Related in: MedlinePlus