Hydra morphogenesis as phase-transition dynamics

Oded Agam; Erez Braun

doi:10.1209/0295-5075/ace4f0

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arXiv · 2304.01801

Hydra morphogenesis as phase-transition dynamics

Oded Agam·Erez Braun

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Abstract

We utilize whole-body Hydra regeneration from a small tissue segment to develop a physics framework for animal morphogenesis. Introducing experimental controls over this process, an external electric field and a drug that blocks gap junctions, allows us to characterize the essential step in the morphological transition - from a spherical shape to an elongated spheroid. We find that spatial fluctuations of the Ca2+ distribution in the Hydra's tissue drive this transition and construct a field-theoretic model that explains the morphological transition as a first-order-like phase transition resulting from the coupling of the Ca2+ field and the tissue's local curvature. Various predictions of this model are verified experimentally.

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physics.bio-ph cond-mat.dis-nn cond-mat.stat-mech nlin.AO nlin.PS

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BibTeX RIS

Oded Agam, Erez Braun. 2023-04-04. Hydra morphogenesis as phase-transition dynamics. https://doi.org/10.1209/0295-5075%2Face4f0

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