Baruch I. Kanner

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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(More)
Polyclonal antibodies were generated against the major polypeptide (73,000 mol. wt) present in a highly purified preparation of the [Na+ + K+]coupled L-glutamate transporter from rat brain. These antibodies were able to selectively immunoprecipitate the 73,000 mol. wt polypeptide as well as most of the L-glutamate transport activity--as assayed upon(More)
Synaptic transmission of most vertebrate synapses is thought to be terminated by rapid transport of the neurotransmitter into presynaptic nerve terminals or neuroglia. L-Glutamate is the major excitatory transmitter in brain and its transport represents the mechanism by which it is removed from the synaptic cleft and kept below toxic levels. Here we use an(More)
This review will focus on the bioenergetics, mechanism, and molecular basis of neurotransmitter transport. As indicated in the next section, these processes play an important role in the overall process of synaptic transmission. During the last few years, direct evidence has been obtained that these processes are coupled chemiosmotically, i.e., the(More)
This study addresses the binding of ions and the permeation of substrates during function of the GABA transporter GAT1. GAT1 was expressed in Xenopus oocytes and studied electrophysiologically as well as with [3H]GABA flux; GAT1 was also expressed in mammalian cells and studied with [3H]GABA and [3H]tiagabine binding. Voltage jumps, Na+ and Cl-(More)
Glutamate transporters from the central nervous system play a crucial role in the clearance of the transmitter from the synaptic cleft. Glutamate is cotransported with sodium ions, and the electrogenic translocation cycle is completed by countertransport of potassium. Mutants that cannot interact with potassium are only capable of catalyzing electroneutral(More)
Antibodies directed against a glutamate transporter (GLT-1) purified from rat brain were applied to cryostat sections of rat and macaque monkey retinae. In the brain, GLT-1 expression is found mainly in astrocytes, and therefore it has been suggested that GLT-1 may be a glutamate transporter specific to glial cells. However, in the rat retina, cones and two(More)
Glutamate transporters maintain low synaptic concentrations of neurotransmitter by coupling uptake to flux of other ions. After cotransport of glutamic acid with Na+, the cycle is completed by countertransport of K+. We have identified an amino acid residue (glutamate 404) influencing ion coupling in a domain of the transporter implicated previously in(More)
The membrane topology of GAT-1, a sodium- and chloride-coupled gamma-aminobutyric acid transporter from rat brain, has been probed using N-glycosylation scanning mutagenesis. Overall, the results support the theoretical 12-transmembrane segment model. This model (based on hydropathy analysis) was originally proposed for GAT-1 and adopted for all other(More)
Neurotransmitter:sodium symporters (NSS) have a critical role in regulating neurotransmission and are targets for psychostimulants, anti-depressants and other drugs. Whereas the non-homologous glutamate transporters mediate chloride conductance, in the eukaryotic NSS chloride is transported together with the neurotransmitter. In contrast, transport by the(More)