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Galpha12/13 regulate epiboly by inhibiting E-cadherin activity and modulating the actin cytoskeleton
Fang Lin1, Songhai Chen, Diane S Sepich
1Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA. fang-lin@uiowa.edu
The Journal of Cell Biology
|March 25, 2009
Summary
G protein alpha subunits Gα(12/13) are crucial for zebrafish gastrulation epiboly. They regulate cell adhesion via E-cadherin and control actin cytoskeleton organization for proper blastoderm movement.
Area of Science:
- Developmental biology
- Cell biology
- Molecular biology
Background:
- Epiboly is a key process in zebrafish gastrulation involving coordinated cell movements.
- The precise cellular and molecular mechanisms governing epiboly are not fully understood.
Purpose of the Study:
- To investigate the role of G protein alpha subunits Gα(12/13) in zebrafish gastrulation epiboly.
- To elucidate the cellular and molecular mechanisms by which Gα(12/13) signaling influences epiboly.
Main Methods:
- Utilized zebrafish gastrulae with altered Gα(12/13) signaling.
- Performed biochemical and genetic analyses.
- Investigated E-cadherin activity and cell adhesion.
- Examined actin cytoskeleton organization via RhoGEF/Rho pathway.
Main Results:
- Altered Gα(12/13) signaling caused delayed deep cell epiboly, abnormal dorsal forerunner cell movement, and blastoderm cell dissociation.
- Gα(12/13) were found to associate with E-cadherin, inhibiting its adhesive function.
- Gα(12/13) signaling modulates actin cytoskeleton organization through a RhoGEF/Rho-dependent pathway.
Conclusions:
- Gα(12/13) signaling plays a critical role in regulating zebrafish gastrulation epiboly.
- Gα(12/13) control epiboly through two distinct mechanisms: limiting E-cadherin activity and modulating actin cytoskeleton organization.
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