Microinjected anti-actin antibodies decrease gap junctional intercellular commmunication in cultured astrocytes.

Carsten Theiss; Karl Meller

doi:10.1006/excr.2002.5652

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Microinjected anti-actin antibodies decrease gap junctional intercellular commmunication in cultured astrocytes.

Carsten Theiss·Karl Meller

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Abstract

The purpose of the present study was to investigate the influence of the actin cytoskeleton on gap junctional intercellular communication (GJIC) in cultured astrocytes. This report describes an decrease of GJIC following microinjection of anti-actin antibodies or cytochalasin D treatment. Dye transfer of microinjected neurobiotin was used to assay gap junctional permeability in cultured astrocytes. Besides this translocation of connexins to the plasma membrane we investigated subsequent anti-actin antibody injection. While control cultures exhibited intensive dye spreading of microinjected neurobiotin, GJIC was impaired by microinjection of anti-actin antibodies. Additionally, impaired GJIC was observed after cytochalasin D treatment for 15 min. After the drug had been washed out, a recovery of GJIC was achieved. Cultured astrocytes exhibited a prominent actin cytoskeleton, with strong staining of actin filaments at the plasma membrane. Confocal laser scanning microscopy revealed an impaired translocation of Cx 43 from the Golgi apparatus to the cell membrane of cell processes following anti-actin antibody injection. These results suggest that the morphological integrity of microfilaments seems to be fundamental for GJIC, probably by means of associations among actin filaments, actin binding proteins, and Cx 43 at the plasma membrane or indirectly through the transport of connexins from the cytoplasm to the cell membrane.

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Actin Cytoskeleton Animals Antibodies Astrocytes Cell Communication Cell Compartmentation Cells, Cultured Central Nervous System Connexin 43 Cytochalasin D Down-Regulation Fetus Fluorescent Dyes Gap Junctions Immunohistochemistry Microinjections Rats Journal Article

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Carsten Theiss, Karl Meller. 2002-12-10. Microinjected anti-actin antibodies decrease gap junctional intercellular commmunication in cultured astrocytes.. https://doi.org/10.1006/excr.2002.5652

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