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Successful development of tissue structures requires different collective cell migration patterns or phenotypes. Two examples of collective migration phenotypes in epithelial morphogenic processes, such as tubulogenesis, are rotational and invasive. Rotational collective migration phenotypes (RCM) typically lead to acinar structures, and invasive collective migration (ICM) phenotypes lead to duct-like structures. How cells adopt these different phenotypes is still largely unknown. Here, we investigate how cell–cell adhesion marker P-cadherin (CDH3) and mechanical cell–matrix interactions, including matrix deformations, protrusions, and focal adhesions, control rotational or invasive phenotypes during tubulogenesis. To accomplish our objective, we created a custom 3D microfluidic assay to perform live-cell imaging of epithelial clusters or cysts [wild-type (WT) and CDH3-depleted (CDH3-/-)] undergoing tubulogenesis, while simultaneously measuring matrix deformation rates. Our findings reveal WT epithelial cysts maintain rotational phenotypes, but transition to an invasive phenotype to undergo tubulogenesis. Furthermore, we demonstrate ICM phenotypes correlate with higher matrix deformation rates compared to rotational phenotypes. Our studies reveal CDH3 is required for epithelial cysts to transition from rotational to ICM phenotypes, associated with decreased matrix deformation rates. Without CDH3, epithelial cysts lose their ability to adopt ICM phenotypes, which can be rescued by RhoA activation. Finally, we demonstrate that the RhoA-rescued ICM phenotype is mediated, in part, by increased matrix deformation rates and vinculin recruitment to focal adhesion sites.
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α–Catenin-dependent vinculin recruitment to adherens junctions is antagonistic to focal adhesions
Vinculin is a protein found in both focal adhesions (FAs) and adherens junctions (AJs) which regulates actin connectivity to these structures. Many studies have demonstrated that mechanical perturbations of cells result in enhanced recruitment of vinculin to FAs and/or AJs. Likewise, many other studies have shown “cross-talk” between FAs and AJs. Vinculin itself has been suggested to be a probable regulator of this adhesion cross-talk. In this study we used MDCK as a model system of epithelia, developing cell lines in which vinculin recruitment was reduced or enhanced at AJs. Careful analysis of these cells revealed that perturbing vinculin recruitment to AJs resulted in a reduction of detectable FAs. Interestingly the cross-talk between these two structures was not due to a limited pool of vinculin, as increasing expression of vinculin did not rescue FA formation. Instead, we demonstrate that vinculin translocation between AJs and FAs is necessary for actin cytoskeleton rearrangements that occur during cell migration, which is necessary for large, well-formed FAs. Last, we show using a wound assay that collective cell migration is similarly hindered when vinculin recruitment is reduced or enhanced at AJs, highlighting that vinculin translocation between each compartment is necessary for efficient collective migration.
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- PAR ID:
- 10398428
- Editor(s):
- Yap, Alpha
- Date Published:
- Journal Name:
- Molecular Biology of the Cell
- Volume:
- 33
- Issue:
- 11
- ISSN:
- 1059-1524
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1091/mbc.E22-02-0071
