A tension-adhesion feedback loop in plant epidermis
Abstract
Mechanical forces have emerged as coordinating signals for most cell functions. Yet, because forces are invisible, mapping tensile stress patterns in tissues remains a major challenge in all kingdoms. Here we take advantage of the adhesion defects in the Arabidopsis mutant quasimodo1 (qua1) to deduce stress patterns in tissues. By reducing the water potential and epidermal tension in planta, we rescued the adhesion defects in qua1, formally associating gaping and tensile stress patterns in the mutant. Using suboptimal water potential conditions, we revealed the relative contributions of shape- and growth-derived stress in prescribing maximal tension directions in aerial tissues. Consistently, the tension patterns deduced from the gaping patterns in qua1 matched the pattern of cortical microtubules, which are thought to align with maximal tension, in wild-type organs. Conversely, loss of epidermis continuity in the qua1 mutant hampered supracellular microtubule alignments, revealing that coordination through tensile stress requires cell-cell adhesion.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data file for cell_separation_analysis pipeline has been provided and a reference to Github (where the code is now stored) has been added in the main text and Material and methods.
Article and author information
Author details
Funding
H2020 European Research Council (ERC-2013-CoG-615739)
- Olivier Hamant
European Molecular Biology Organization (EMBO ALTF 168-2015)
- Yuchen Long
H2020 European Research Council (ERC-2012-StG-307387)
- Arezki Boudaoud
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Dominique C Bergmann, Stanford University/HHMI, United States
Version history
- Received: December 18, 2017
- Accepted: April 20, 2018
- Accepted Manuscript published: April 23, 2018 (version 1)
- Version of Record published: May 22, 2018 (version 2)
- Version of Record updated: October 16, 2018 (version 3)
- Version of Record updated: March 23, 2020 (version 4)
Copyright
© 2018, Verger et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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