Sequence and expression of a novel GABAA receptor alpha subunit.
Cloned cDNA encoding the bovine alpha 4 subunit of the GABAA receptor has been isolated. The predicted 51 amino acid long mature protein contains an exceptionally long intracellular domain and shares 53-56% sequence similarity to the previously characterized alpha 1, alpha 2 and alpha 3 subunits. Co-expression of alpha 4 and beta 1 in Xenopus oocytes resulted in the formation of GABA-gated chloride channels with expected pharmacology, although no benzodiazepine potentiation was observed. Northern analysis indicates that a 4 kb alpha 4 mRNA is expressed in the calf cerebellum, cortex and hippocampus but is barely detectable in the rat brain.
Ymer
S
S
Laboratory of Molecular Neuroendocrinology, Center for Molecular Biology (ZMBH), Heidelberg, FRG.
Draguhn
A
A
Köhler
M
M
Schofield
P R
PR
Seeburg
P H
PH
D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D002417:Cattle; D018118:Chloride Channels; D002712:Chlorides / Q000378:metabolism; D003001:Cloning, Molecular; D004247:DNA / Q000302:isolation & purification; D015870:Gene Expression; D008565:Membrane Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D009865:Oocytes / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011963:Receptors, GABA-A / Q000235:genetics* / Q000302:isolation & purification; D014981:Xenopus; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D018118:Chloride Channels; D002712:Chlorides; D008565:Membrane Proteins; D012333:RNA, Messenger; D011963:Receptors, GABA-A; D005680:gamma-Aminobutyric Acid; D004247:DNA