Hannezo E, Scheele CLGJ, Moad M, Drogo N, Heer R, Sampogna RV, van Rheenen J, Simons BD. A Unifying Theory of Branching Morphogenesis.
Cell 2017;
171:242-255.e27. [PMID:
28938116 PMCID:
PMC5610190 DOI:
10.1016/j.cell.2017.08.026]
[Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 06/20/2017] [Accepted: 08/15/2017] [Indexed: 11/23/2022]
Abstract
The morphogenesis of branched organs remains a subject of abiding interest. Although much is known about the underlying signaling pathways, it remains unclear how macroscopic features of branched organs, including their size, network topology, and spatial patterning, are encoded. Here, we show that, in mouse mammary gland, kidney, and human prostate, these features can be explained quantitatively within a single unifying framework of branching and annihilating random walks. Based on quantitative analyses of large-scale organ reconstructions and proliferation kinetics measurements, we propose that morphogenesis follows from the proliferative activity of equipotent tips that stochastically branch and randomly explore their environment but compete neutrally for space, becoming proliferatively inactive when in proximity with neighboring ducts. These results show that complex branched epithelial structures develop as a self-organized process, reliant upon a strikingly simple but generic rule, without recourse to a rigid and deterministic sequence of genetically programmed events.
Branching morphogenesis follows conserved statistical rules in multiple organs
Ductal tips grow and branch as default state and stop dividing in high-density regions
Model reproduces quantitatively organ properties in a parameter-free manner
Shows that complex organ formation proceeds in a stochastic, self-organized manner
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