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Title: Patterning of morphogenetic anisotropy fields
Orientational order, encoded in anisotropic fields, plays an important role during the development of an organism. A striking example of this is the freshwater polypHydra, where topological defects in the muscle fiber orientation have been shown to localize to key features of the body plan. This body plan is organized by morphogen concentration gradients, raising the question how muscle fiber orientation, morphogen gradients and body shape interact. Here, we introduce a minimal model that couples nematic orientational order to the gradient of a morphogen field. We show that on a planar surface, alignment to a radial concentration gradient can induce unbinding of topological defects, as observed during budding and tentacle formation inHydra, and stabilize aster/vortex-like defects, as observed at aHydra’s mouth. On curved surfaces mimicking the morphologies ofHydrain various stages of development—from spheroid to adult—our model reproduces the experimentally observed reorganization of orientational order. Our results suggest how gradient alignment and curvature effects may work together to control orientational order during development and lay the foundations for future modeling efforts that will include the tissue mechanics that drive shape deformations.  more » « less
Award ID(s):
2041459
PAR ID:
10478910
Author(s) / Creator(s):
; ;
Publisher / Repository:
US National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
120
Issue:
13
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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