Shaker-type potassium channel subunits differentially control oligodendrocyte progenitor proliferation.
Oligodendrocyte precursor (OP) cells are exposed to multiple extrinsic signals that control their proliferation and differentiation. Previous cell proliferation studies and electrophysiological analysis in cultured cells and in brain slices have suggested that outward potassium channels, particularly Kv1 subunits, may have a prominent role in OP cell proliferation. In the present study, we assessed to what extent overexpression of Kv1.3, Kv1.4, Kv1.5, and Kv1.6 can affect OP cell proliferation and differentiation in culture. We observed that overexpression of Kv1.3 or Kv1.4 increased OP cell proliferation in the absence of mitogens, whereas Kv1.6 overexpression inhibited mitogen-induced OP cell cycle progression. Interestingly, Kv1.3, Kv1.4, Kv1.5, and Kv1.6 overexpression did not interfere with the kinetics of oligodendrocyte differentiation. This study represents the first demonstration that the activity of potassium channels containing distinct Kv1 subunit proteins directly controls oligodendroglial proliferation in the presence of mitogens, as well as in growth factor-free conditions.
Vautier
François
F
Laboratory of Cellular and Synaptic Neurophysiology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA.
Belachew
Shibeshih
S
Chittajallu
Ramesh
R
Gallo
Vittorio
V
D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D009836:Oligodendroglia / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D015221:Potassium Channels / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D021122:Protein Subunits / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D051637:Shaker Superfamily of Potassium Channels; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology
D010982:Platelet-Derived Growth Factor; D015221:Potassium Channels; D021122:Protein Subunits; D051637:Shaker Superfamily of Potassium Channels