Cloning and expression of a rat brain GABA transporter.
A complementary DNA clone (designated GAT-1) encoding a transporter for the neurotransmitter gamma-aminobutyric acid (GABA) has been isolated from rat brain, and its functional properties have been examined in Xenopus oocytes. Oocytes injected with GAT-1 synthetic messenger RNA accumulated [3H]GABA to levels above control values. The transporter encoded by GAT-1 has a high affinity for GABA, is sodium-and chloride-dependent, and is pharmacologically similar to neuronal GABA transporters. The GAT-1 protein shares antigenic determinants with a native rat brain GABA transporter. The nucleotide sequence of GAT-1 predicts a protein of 599 amino acids with a molecular weight of 67 kilodaltons. Hydropathy analysis of the deduced protein suggests multiple transmembrane regions, a feature shared by several cloned transporters; however, database searches indicate that GAT-1 is not homologous to any previously identified proteins. Therefore, GAT-1 appears to be a member of a previously uncharacterized family of transport molecules.
Guastella
J
J
Division of Biology, California Institute of Technology, Pasadena 91125.
Nelson
N
N
Nelson
H
H
Czyzyk
L
L
Keynan
S
S
Miedel
M C
MC
Davidson
N
N
Lester
H A
HA
Kanner
B I
BI
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D002713:Chlorine / Q000502:physiology; D003001:Cloning, Molecular; D050485:GABA Plasma Membrane Transport Proteins; D015870:Gene Expression; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D026901:Membrane Transport Proteins; D008845:Microinjections; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism; D027361:Organic Anion Transporters; D011061:Poly A / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D012964:Sodium / Q000502:physiology; D013329:Structure-Activity Relationship; D014981:Xenopus; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D002352:Carrier Proteins; D050485:GABA Plasma Membrane Transport Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D027361:Organic Anion Transporters; D012333:RNA, Messenger; C493415:Slc6a1 protein, rat; D011061:Poly A; D002713:Chlorine; D005680:gamma-Aminobutyric Acid; D012964:Sodium