Radially-patterned cell behaviours during tube budding from an epithelium
Abstract
The budding of tubular organs from flat epithelial sheets is a vital morphogenetic process. Cell behaviours that drive such processes are only starting to be unraveled. Using live-imaging and novel morphometric methods we show that in addition to apical constriction, radially-oriented directional intercalation of cells plays a major contribution to early stages of invagination of the salivary gland tube in the Drosophila embryo. Extending analyses in 3D, we find that near the pit of invagination, isotropic apical constriction leads to strong cell-wedging. Further from the pit cells interleave circumferentially, suggesting apically-driven behaviours. Supporting this, junctional myosin is enriched in, and neighbour exchanges are biased towards the circumferential orientation. In a mutant failing pit specification, neither are biased due to an inactive pit. Thus, tube budding involves radially-patterned pools of apical myosin, medial as well as junctional, and radially-patterned 3D-cell behaviours, with a close mechanical interplay between invagination and intercalation.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures.
Article and author information
Author details
Funding
Medical Research Council (U105178780)
- Yara E Sanchez-Corrales
- Guy B Blanchard
- Katja Röper
Biotechnology and Biological Sciences Research Council (BB/J010278/1)
- Guy B Blanchard
Wellcome (100329/Z/12/Z)
- Guy B Blanchard
Isaac Newton Trust (15.23(k))
- Guy B Blanchard
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Stefan Luschnig
Version history
- Received: February 6, 2018
- Accepted: July 16, 2018
- Accepted Manuscript published: July 17, 2018 (version 1)
- Accepted Manuscript updated: July 23, 2018 (version 2)
- Accepted Manuscript updated: July 24, 2018 (version 3)
- Version of Record published: August 13, 2018 (version 4)
Copyright
© 2018, Sanchez-Corrales 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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