Using optogenetics to link myosin patterns to contractile cell behaviors during convergent extension
R Marisol Herrera-Perez1, Christian Cupo1, Cole Allan1
1Department of Mechanical Engineering, Columbia University, New York, New York.
Biophysical Journal
|July 22, 2021
Summary
New optogenetic tools reveal how Rho1 signaling and myosin patterns control epithelial tissue shape during Drosophila development. Manipulating these factors impacts cell behaviors crucial for morphogenesis and axis elongation.
Area of Science:
- Developmental Biology
- Cell Biology
- Biophysics
Background:
- Epithelial tissue shape changes are driven by actomyosin contractility.
- Planar-polarized myosin II, regulated by Rho1 signaling, is crucial for Drosophila axis elongation.
- The precise influence of myosin patterns on simultaneous cell behaviors during morphogenesis remains unclear.
Purpose of the Study:
- To investigate how specific myosin patterns affect cell behaviors during epithelial morphogenesis.
- To develop optogenetic tools for precise manipulation of Rho1 signaling and myosin dynamics.
- To analyze the impact of Rho1 activity perturbations on cell intercalation, shape, and area fluctuations.
Main Methods:
- Development of optogenetic tools (optoGEF and optoGAP) to control Rho1 signaling.
- Application of these tools to the Drosophila germband epithelium during axis elongation.
- Analysis of myosin II patterns and cell behaviors using live imaging and microscopy.
Main Results:
- Uniform Rho1 activation/inactivation rapidly disrupted planar-polarized myosin patterns.
- Both perturbations impaired axis elongation and cell intercalation.
- Distinct effects on cell area fluctuations and packing were observed, linked to myosin pool changes.
Conclusions:
- Acute optogenetic manipulation of Rho1 activity can override endogenous myosin patterns.
- Rho1 activity levels and medial/junctional myosin balance are critical for cell rearrangements and tissue mechanics.
- These findings offer insights into the regulation of morphogenesis and tissue flow.
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