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Published on: August 9, 2016
Permeability of gap junctions at the segmental border in insect epidermis
Cell
|February 1, 1982
Summary
Cell-cell communication in insect epidermis is segment-specific. Gap junctions at segmental borders may have unique permeability, restricting dye transfer between developmental compartments in milkweed bugs and blowflies.
Area of Science:
- Developmental biology
- Cell biology
- Insect physiology
Background:
- Cell-cell communication is crucial for tissue development.
- Segmental borders define developmental compartments in insects.
- Gap junctions mediate intercellular communication.
Purpose of the Study:
- To investigate cell-cell communication patterns across segmental borders in insect epidermis.
- To determine if gap junctions restrict communication between developmental compartments.
- To compare communication in the milkweed bug (Oncopeltus fasciatus) and blowfly (Calliphora erythrocephala).
Main Methods:
- Ionic coupling assays to assess electrical communication.
- Microinjection of fluorescent dyes (Lucifer Yellow) and anionic tracers (lead-EDTA).
- Mapping dye transfer patterns in larval epidermis of Oncopeltus fasciatus and Calliphora erythrocephala.
Main Results:
- Epidermal cells were ionically coupled within segments in both species.
- Lucifer Yellow transfer was restricted to cells within the same segment, not crossing segmental borders.
- Lead-EDTA crossed segmental borders freely in Calliphora, indicating differential permeability.
- Failure of Lucifer Yellow transfer suggests altered gap junction properties at segmental borders.
Conclusions:
- Insect epidermal cells communicate differently across segmental borders compared to within segments.
- Gap junctions at segmental borders exhibit distinct permeability characteristics.
- This suggests a role for selective permeability in maintaining developmental compartmentalization.
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