Subpopulation of nestin-expressing progenitor cells in the adult murine hippocampus shows electrophysiological and morphological characteristics of astrocytes.
Based on the expression of glial fibrillary acidic protein (GFAP), a recent hypothesis considered stem or progenitor cells in the adult hippocampus to be a type of astrocyte. In a complementary approach, we used transgenic mice expressing green fluorescent protein (GFP) under the promoter for nestin, an intermediate filament present in progenitor cells, to demonstrate astrocytic features in nestin-GFP-positive cells. Morphologically, two subpopulations of nestin-GFP-positive cells were distinguishable; one had an elaborate tree of processes in the granule cell layer and expression of GFAP (but not of S100beta, another astrocytic marker). Electron microscopy revealed vascular end feet of nestin-positive cells, further supporting astrocytic differentiation. Electrophysiological examination of nestin-GFP-positive cells on acutely isolated hippocampal slices showed passive current characteristics of astrocytes in one subset of cells. Among the nestin-GFP-expressing cells with lacking astrocytic features, two cell types could be identified electrophysiologically: cells with delayed-rectifying potassium currents and a very small number of cells with sodium currents, potentially representing signs of the earliest steps of neuronal differentiation.
Filippov
Vitali
V
Max Delbrück Center for Molecular Medicine (MDS) Berlin-Buch, Robert-Rössle-Strasse 10, 13125 Berlin, Germany.
Kronenberg
Golo
G
Pivneva
Tatjyana
T
Reuter
Katja
K
Steiner
Barbara
B
Wang
Li Ping
LP
Yamaguchi
Masahiro
M
Kettenmann
Helmut
H
Kempermann
Gerd
G
D000367:Age Factors; D000818:Animals; D001253:Astrocytes / Q000502:physiology* / Q000648:ultrastructure; D002196:Capillaries; D018891:Dentate Gyrus / Q000098:blood supply / Q000166:cytology*; D005456:Fluorescent Dyes; D049452:Green Fluorescent Proteins; D007381:Intermediate Filament Proteins / Q000235:genetics*; D007546:Isoquinolines; D008164:Luminescent Proteins / Q000235:genetics; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D016253:Microscopy, Immunoelectron; D009419:Nerve Tissue Proteins; D064231:Nestin; D015221:Potassium Channels / Q000502:physiology; D011401:Promoter Regions, Genetic; D013234:Stem Cells / Q000378:metabolism* / Q000648:ultrastructure
D005456:Fluorescent Dyes; D007381:Intermediate Filament Proteins; D007546:Isoquinolines; D008164:Luminescent Proteins; D009419:Nerve Tissue Proteins; C577485:Nes protein, mouse; D064231:Nestin; D015221:Potassium Channels; D049452:Green Fluorescent Proteins; C017475:lucifer yellow