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arXiv · 2403.01294

Anomalous mass dependency in Hydra endoderm cell cluster diffusion

Abstract

Tissue organization plays a crucial role in morphogenesis, wound healing and cancer metastasis. Hydra, known for its regenerative capabilities, serves as an excellent model for studying cellular structures, particularly in pattern formation and the diffusion of cell clusters. Established experimental protocols enable the examination of regeneration and tissue segregation through optical microscopy. Recent experiments challenge previous theories by suggesting that cell collective behavior is a key factor in hydra cell aggregate organization. Utilizing image treatment techniques on fluorescent images from Hydra's segregation experiment, we track endoderm cell clusters and investigate the relationship between their diffusion constant and cluster size. In contrast to results observed in non-active matter, we discover a nearly constant dependence of diffusion on cluster mass. This finding contributes to understanding the rapid segregation observed in recent experiments and holds implications for general cellular tissue processes.

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Aline Lütz, Carine Beatrici, Lívio Amaral, Leonardo Brunnet. 2024-03-02. Anomalous mass dependency in Hydra endoderm cell cluster diffusion. https://arxiv.org/abs/2403.01294

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