An RNAi screen unravels the complexities of Rho GTPase networks in skin morphogenesis
- The Rockefeller University, United States
Abstract
During mammalian embryogenesis, extensive cellular remodeling is needed for tissue morphogenesis. As effectors of cytoskeletal dynamics, Rho GTPases and their regulators are likely involved, but their daunting complexity has hindered progress in dissecting their functions. We overcome this hurdle by employing high throughput in utero RNAi-mediated screening to identify key Rho regulators of skin morphogenesis. Our screen unveiled hitherto unrecognized roles for Rho-mediated cytoskeletal remodeling events that impact hair follicle specification, differentiation, downgrowth and planar cell polarity. Coupling our top hit with gain/loss-of-function genetics, interactome proteomics and tissue imaging, we show that RHOU, an atypical Rho, governs the cytoskeletal-junction dynamics that establish columnar shape and planar cell polarity in epidermal progenitors. Conversely, RHOU downregulation is required to remodel to a conical cellular shape that enables hair bud invagination and downgrowth. Our findings underscore the power of coupling screens with proteomics to unravel the physiological significance of complex gene families.
Data availability
Sequencing data have been deposited in NCBI GEO under accession number GSE123047. All data generated or analysed during this study are included in the manuscript and supporting files
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RNA-sequencing from E14.5 epidermal cells from shScr and shRhou transduced miceNCBI Gene Expression Omnibus, GSE123047.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Elaine Fuchs
Canadian Institutes of Health Research
- Melanie Laurin
Burroughs Wellcome Fund (Postdoctoral Enrichment Program Award)
- Nicholas C Gomez
National Institutes of Health (Ruth L. Kirschstein National Research Service Award F32CA221353)
- Nicholas C Gomez
Human Frontier Science Program
- Ataman Sendoel
Marie Curie Foundation
- Ataman Sendoel
Cancer Research Society
- Melanie Laurin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mouse strains were housed in an AAALAC-accredited facility and experiments were conducted according to the Rockefeller University's Institutional Animal Care and Use Committee, and NIH guidelines for Animal Care and Use.All animal procedures used in this study are described in our #17020-H protocol named Lentiviral RNAi and Skin, which had been previously reviewed and approved by the Rockefeller University Institutional Animal Care and Use Committee (IACUC)
Copyright
© 2019, Laurin 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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An RNAi screen unravels the complexities of Rho GTPase networks in skin morphogenesis
eLife 8:e50226.
https://doi.org/10.7554/eLife.50226
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