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Tissue flows are tuned by actomyosin-dependent mechanics in developing embryos
R Marisol Herrera-Perez1, Christian Cupo1, Cole Allan1
1Department of Mechanical Engineering, Columbia University, New York, New York, 10027, USA.
PRX Life
|May 13, 2024
Summary
Embryonic epithelial tissue flow is regulated by actomyosin contractility. Manipulating actomyosin tension alters tissue mechanics, showing that isotropic tension increases solid-like properties, while anisotropic tension fluidizes the tissue.
Area of Science:
- Developmental Biology
- Cell Biology
- Biophysics
Background:
- Epithelial tissue flows are crucial for embryonic development and morphogenesis.
- The mechanical properties of embryonic epithelial tissues and the factors governing them are not fully understood.
- Actomyosin contractility influences cell and cytoskeletal network mechanics, but its in vivo role in embryonic tissue dynamics is unclear.
Purpose of the Study:
- To investigate how actomyosin-dependent tensions influence the mechanical properties and flow dynamics of embryonic epithelial tissues.
- To dissect the role of cell-generated tensions in regulating tissue mechanics during embryonic development.
Main Methods:
- Utilized optogenetic tools for precise spatiotemporal manipulation of actomyosin contractility in the Drosophila germband epithelium.
- Quantified changes in tissue mechanical properties, cell rearrangements, and tissue-level flows in response to altered actomyosin activity.
Main Results:
- Optogenetic manipulation of actomyosin contractility significantly altered the solid-fluid mechanical properties of the germband epithelium.
- Increased actomyosin activation led to higher overall tension but decreased tension anisotropy, resulting in more solid-like tissue properties and reduced flow.
- Decreased actomyosin activity reduced both tension level and anisotropy, leading to more solid-like properties than wild-type but less so than activation.
Conclusions:
- Epithelial tissue flow during embryogenesis is controlled by actomyosin-dependent regulation of tissue mechanical properties.
- Tissue mechanics are modulated by tension levels and anisotropy: isotropic tension promotes solid-like behavior, while anisotropic tension promotes fluidization.
- Coordinated regulation of actomyosin activity is essential for rapid tissue remodeling during embryonic development.
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