Dynamic contacts: rearranging adherens junctions to drive epithelial remodelling
1RIKEN Center for Developmental Biology, 2-2-3 Chuo-ku, Kobe 650-0047, Japan.
Nature Reviews. Molecular Cell Biology
|May 15, 2014
Summary
Epithelial cell remodeling, crucial for development, is driven by changes in adherens junctions (AJs). Actomyosin contraction at AJs, regulated by RHO GTPases, controls cell shape and movement.
Area of Science:
- Cell Biology
- Developmental Biology
- Biophysics
Background:
- Epithelial cells exhibit dynamic behaviors like shape changes and movement, essential during embryonic development and adult tissue maintenance.
- Adherens junctions (AJs), composed of cadherins and associated proteins, are increasingly recognized for their critical role in regulating these cellular dynamics.
- AJ remodeling influences epithelial reshaping through mechanisms like planar-polarized apical constriction, driven by actomyosin contractility.
Purpose of the Study:
- To elucidate the role of adherens junction remodeling in epithelial cell dynamics.
- To understand how actomyosin contractility at AJs contributes to epithelial reshaping processes.
- To investigate the involvement of RHO GTPases in regulating AJ-associated cytoskeletal dynamics.
Main Methods:
- Microscopy techniques to visualize adherens junction dynamics and cell morphology.
- Biochemical assays to study protein interactions and complex formation at adherens junctions.
- Genetic and pharmacological manipulation of RHO GTPase pathways and actomyosin components.
Main Results:
- Adherens junction remodeling, including changes in form (linear to punctate), directly correlates with epithelial cell rearrangement and shape changes.
- Planar-polarized apical constriction, a key epithelial reshaping mechanism, is mediated by the contraction of actomyosin networks associated with adherens junctions.
- RHO GTPases and their downstream effectors are demonstrated to be critical regulators of actin polymerization and actomyosin contractility at adherens junctions during epithelial morphogenesis.
Conclusions:
- Adherens junction remodeling is a fundamental mechanism controlling epithelial cell behaviors during development.
- Actomyosin contractility at adherens junctions, finely tuned by RHO GTPases, drives significant epithelial shape transformations.
- Understanding these processes provides insights into both normal development and pathological conditions involving epithelial dysfunction.
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