Unified quantitative characterization of epithelial tissue development
Abstract
Understanding the mechanisms regulating development requires a quantitative characterization of cell processes including cell divisions, rearrangements, cell size and shape changes, and apoptoses. We developed a multiscale formalism that unifies and relates the characterizations of each individual cell process and of epithelial tissue growth and morphogenesis during development. We applied this formalism to two Drosophila proliferative tissues and by analyzing more than 9 million cell contours, we obtained comprehensive statistical maps of morphogenetic events linking cell and tissue scale dynamics. By quantifying each cell process separately in both wild-type and mutant conditions, we analyzed the roles of cell proliferation and its interplay with cell rearrangements and cell shape changes. Furthermore, by combining the formalism with mechanical stress measurement, we uncovered unexpected interplays between the patterns of tissue elongation, cell division orientation and stress orientations. Collectively, our formalism provides a novel and rigorous approach to uncover mechanisms governing tissue development.
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© 2015, Guirao 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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