Dataset Information

Coherent Timescales and Mechanical Structure of Multicellular Aggregates.

ABSTRACT: Multicellular aggregates are an excellent model system to explore the role of tissue biomechanics in specifying multicellular reorganization during embryonic developments and malignant invasion. Tissue-like spheroids, when subjected to a compressive force, are known to exhibit liquid-like behaviors at long timescales (hours), largely because of cell rearrangements that serve to effectively dissipate the applied stress. At short timescales (seconds to minutes), before cell rearrangement, the mechanical behavior is strikingly different. The current work uses shape relaxation to investigate the structural characteristics of aggregates and discovers two coherent timescales: one on the order of seconds, the other tens of seconds. These timescales are universal, conserved across a variety of tested species, and persist despite great differences in other properties such as tissue surface tension and adhesion. A precise mathematical theory is used to correlate the timescales with mechanical properties and reveals that aggregates have a relatively strong envelope and an unusually "soft" interior (weak bulk elastic modulus). This characteristic is peculiar, considering that both layers consist of identical units (cells), but is consistent with the fact that this structure can engender both structural integrity and the flexibility required for remodeling. In addition, tissue surface tension, elastic modulus, and viscosity are proportional to each other. Considering that these tissue-level properties intrinsically derive from cellular-level properties, the proportionalities imply precise coregulation of the latter and in particular of the tension on the cell-medium and cell-cell interfaces.

SUBMITTER: Yu M

PROVIDER: S-EPMC6129187 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Coherent Timescales and Mechanical Structure of Multicellular Aggregates.

Yu Miao M Mahtabfar Aria A Beelen Paul P Demiryurek Yasir Y Shreiber David I DI Zahn Jeffrey D JD Foty Ramsey A RA Liu Liping L Lin Hao H

Biophysical journal 20180601 11

Multicellular aggregates are an excellent model system to explore the role of tissue biomechanics in specifying multicellular reorganization during embryonic developments and malignant invasion. Tissue-like spheroids, when subjected to a compressive force, are known to exhibit liquid-like behaviors at long timescales (hours), largely because of cell rearrangements that serve to effectively dissipate the applied stress. At short timescales (seconds to minutes), before cell rearrangement, the mech ...[more]

PMID: 29874619

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Dataset Information

Coherent Timescales and Mechanical Structure of Multicellular Aggregates.

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Coherent Timescales and Mechanical Structure of Multicellular Aggregates.

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