Mechanical strain induces E-cadherin dependent activation of Yap1 and ß-catenin to drive cell cycle re-entry

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Abstract/Contents

Abstract
Mechanical strain regulates the development, organization and function of multicellular tissues, but mechanisms linking mechanical strain and cell-cell junction proteins to cellular responses are poorly understood. We showed that mechanical strain applied to quiescent epithelial cells induced rapid cell cycle re-entry, mediated by independent nuclear accumulation and transcriptional activity of first Yap1 and then β-catenin. Inhibition of Yap1- and β-catenin-mediated transcription blocked cell cycle re-entry and progression through G1 into S phase, respectively. Maintenance of quiescence, Yap1 nuclear exclusion and β-catenin transcriptional responses to mechanical strain required E-cadherin extracellular engagement. Our results indicate that activation of Yap1 and β-catenin is a master regulator of mechanical strain-induced cell proliferation, and cadherins are signaling centers required for cellular responses to externally applied force. While both mechanical force and Wnt Signaling activate β-catenin-mediated transcription to promote proliferation, it is unknown whether mechanical force and Wnt signaling act independently or synergize to activate β-catenin signaling and cell division. We showed that mechanical strain induced Src-dependent phosphorylation of Y654 β-catenin and β-catenin accumulation, increasing β-catenin-mediated transcription. Under these conditions, however, cells accumulated in S/G2 but did not divide. Blocking β-catenin degradation through Casein Kinase I inhibition or Wnt3A addition increased β-catenin-mediated transcription and strain-induced accumulation of S/G2 cells. Significantly, only the combination of mechanical strain and Wnt/β-catenin activation triggered S/G2 cells to divide. These results indicate that strain-induced Src phosphorylation of β-catenin and Wnt-dependent β-catenin stabilization can synergize to increase β-catenin-mediated transcription to a level required for mitosis. Thus local Wnt signaling may fine-tune the effects of global mechanical strain to restrict cell divisions and maintain tissue homeostasis.

Description

Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2016
Issuance monographic
Language English

Creators/Contributors

Associated with Benham-Pyle, Blair Whitney
Associated with Stanford University, Cancer Biology Program.
Primary advisor Nelson, William
Thesis advisor Nelson, William
Thesis advisor Ferrell, James Ellsworth
Thesis advisor Nusse, Roel, 1950-
Thesis advisor Pruitt, Beth
Thesis advisor Weis, William I
Advisor Ferrell, James Ellsworth
Advisor Nusse, Roel, 1950-
Advisor Pruitt, Beth
Advisor Weis, William I

Subjects

Genre Theses

Bibliographic information

Statement of responsibility Blair Whitney Benham-Pyle.
Note Submitted to the Program in Cancer Biology.
Thesis Thesis (Ph.D.)--Stanford University, 2016.
Location electronic resource

Access conditions

Copyright
© 2016 by Blair Whitney Benham-Pyle
License
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

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