Selective RNA editing and subunit assembly of native glutamate receptors.
RNA editing and subunit assembly of ionotropic glutamate receptors (GluRs) were examined in an oligodendrocyte progenitor cell line, CG4, which expresses GluR2-GluR4, GluR6, GluR7, KA1, and KA2. AMPA-evoked currents rapidly desensitize, whereas kainate-evoked currents contain a steady-state component with a nearly linear current-voltage relation and a fast desensitizing component that is inwardly rectifying. The Q/R site is edited > 95% to the arginine codon in GluR2(Q607) mRNA, and < 5% in GluR6(Q621) mRNA. Immunoprecipitation experiments demonstrate that GluR6 and/or GluR7 subunits assemble with KA2, but not with GluR2-GluR4. These results indicate that oligodendrocyte progenitor cells selectively edit and assemble glutamate receptors into at least two functionally and structurally distinct heteromeric channels.
Puchalski
R B
RB
Molecular Neurobiology Laboratory, Salk Institute, La Jolla, California 92037.
Louis
J C
JC
Brose
N
N
Traynelis
S F
SF
Egebjerg
J
J
Kukekov
V
V
Wenthold
R J
RJ
Rogers
S W
SW
Lin
F
F
Moran
T
T
D000818:Animals; D001120:Arginine; D001483:Base Sequence; D002460:Cell Line; D002540:Cerebral Cortex / Q000166:cytology; D003062:Codon; D004553:Electric Conductivity; D005971:Glutamates / Q000494:pharmacology; D018698:Glutamic Acid; D006801:Humans; D007163:Immunosorbent Techniques; D007473:Ion Channels / Q000187:drug effects / Q000502:physiology; D007608:Kainic Acid / Q000494:pharmacology; D008969:Molecular Sequence Data; D009836:Oligodendroglia / Q000187:drug effects / Q000502:physiology*; D016133:Polymerase Chain Reaction; D012313:RNA / Q000737:chemistry; D017393:RNA Editing; D012326:RNA Splicing; D051381:Rats; D017470:Receptors, Glutamate / Q000235:genetics* / Q000502:physiology; D013234:Stem Cells / Q000502:physiology; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
D003062:Codon; D005971:Glutamates; D007473:Ion Channels; D017470:Receptors, Glutamate; D018698:Glutamic Acid; D012313:RNA; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D001120:Arginine; D007608:Kainic Acid