A two-tier junctional mechanism drives simultaneous tissue folding and extension
1Université Côte d'Azur, CNRS, Inserm, iBV, Nice, France.
Developmental Cell
|April 23, 2021
Summary
During embryo development, epithelial cells coordinate complex shape changes. This study reveals how two distinct sets of cell junctions drive simultaneous tissue folding and extension in Drosophila embryos.
Area of Science:
- Developmental Biology
- Cell Biology
- Genetics
Background:
- Embryonic development involves complex tissue shape transformations.
- Mechanisms driving simultaneous tissue folding and extension remain poorly understood.
- Gastrulation and neurulation are critical developmental stages involving these shape changes.
Purpose of the Study:
- To investigate the cellular mechanisms underlying simultaneous tissue folding and extension.
- To identify signaling pathways controlling these coordinated morphogenetic processes.
- To elucidate the role of cell junctions in composite tissue shape changes.
Main Methods:
- Utilized the Drosophila embryo as a model system.
- Focused on mesoderm invagination during gastrulation.
- Analyzed the establishment and function of adherens junctions at different apical-basal positions.
Main Results:
- Demonstrated that prospective mesoderm simultaneously folds and extends.
- Identified two sets of adherens junctions with specialized functions: apical junctions for constriction and lateral junctions for cell intercalation.
- Showed these processes are controlled by synergistic gene patterning from anterior-posterior and dorsal-ventral axes.
Conclusions:
- Epithelial cells utilize multiple, specialized junctional sets to drive complex morphogenetic processes.
- Simultaneous tissue folding and extension are achieved through distinct junctional functions.
- These composite morphogenetic events are orchestrated by synergistic control from orthogonal signaling sources.
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