Branching morphogenesis in the developing kidney is not impacted by nephron formation or integration
Abstract
Branching morphogenesis of the ureteric bud is integral to kidney development; establishing the collecting ducts of the adult organ and driving organ expansion via peripheral interactions with nephron progenitor cells. A recent study suggested that termination of tip branching within the developing kidney involved stochastic exhaustion in response to nephron formation, with such a termination event representing a unifying developmental process evident in many organs. To examine this possibility we have profiled the impact of nephron formation and maturation on elaboration of the ureteric bud during mouse kidney development. We find a distinct absence of random branch termination events within the kidney or evidence that nephrogenesis impacts the branching program or cell proliferation in either tip or progenitor cell niches. Instead, organogenesis proceeds in a manner indifferent to the development of these structures. Hence stochastic cessation of branching is not a unifying developmental feature in all branching organs.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files - see appended Excel files.
Article and author information
Author details
Funding
National Health and Medical Research Council (1002748)
- Melissa H Little
Australian Research Council (DP160103100)
- Nicholas Hamilton
- Ian Macleod Smyth
Human Frontier Science Program (RGP0039/2011)
- Melissa H Little
- Ian Macleod Smyth
National Health and Medical Research Council (1063696)
- Melissa H Little
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 animal experiments in this study were assessed and approved by Monash University or the Murdoch Children's Research Institute Animal Ethics Committees (MARP/2016/144) and were conducted under applicable Australian laws governing the care and use of animals for scientific purposes.
Copyright
© 2018, Short 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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