TGF-alpha induces a stationary, radial-glia like phenotype in cultured astrocytes.
Transgenic mice studies have suggested that transforming growth factor-alpha (TGF-alpha) influences the postnatal differentiation of astrocytes. To understand the role of TGF-alpha during astrocytic differentiation, it is important to determine how this factor affects astrocytes in the absence of other influences. We have thus examined in vitro under serum-free medium conditions the effect of TGF-alpha on the properties of astrocytes derived from the cerebral cortex of newborn rats. When TGF-alpha is added to serum-free medium, most astrocytes lose their polygonal shape and extend two long processes running in opposite directions. This bipolar morphology strikingly resembles that of radial glial cells. Intriguingly, serum inhibits this morphological transformation. TGF-alpha also triggers an increase in glial fibrillary acidic protein (GFAP) expression and a decrease in nestin expression. Another major effect of TGF-alpha is to practically abolish the motility of astrocytes. TGF-alpha, however, does not appear to influence the proliferation and apoptosis of astrocytes. These results suggest that polygonal astrocytes are derived primarily from radial glial cells, and that in vivo TGF-alpha may be instrumental in determining the shape and migratory potential of radial glial cells.
Zhou
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R
Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA.
Wu
X
X
Skalli
O
O
D000375:Aging / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D019521:Body Patterning / Q000187:drug effects / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D048429:Cell Size / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D002540:Cerebral Cortex / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004261:DNA Replication / Q000187:drug effects / Q000502:physiology; D005455:Fluorescent Antibody Technique; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007381:Intermediate Filament Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins; D064231:Nestin; D010641:Phenotype; D051381:Rats; D016211:Transforming Growth Factor alpha / Q000187:drug effects / Q000378:metabolism*
D016895:Culture Media, Serum-Free; D005904:Glial Fibrillary Acidic Protein; D007381:Intermediate Filament Proteins; D009419:Nerve Tissue Proteins; C577485:Nes protein, mouse; C577486:Nes protein, rat; D064231:Nestin; D016211:Transforming Growth Factor alpha