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A study was made of the effects of di- and trivalent cations on homomeric rho 1-type gamma-aminobutyrate (GABA rho 1) receptors expressed in Xenopus oocytes after injection of mRNA coding for the GABA rho 1 subunit. GABA elicited large currents with a Kd approximately 1 microM. The properties of these GABA rho 1 receptors were similar to those of native bicuculline-resistant GABA receptors expressed by retinal mRNA. GABA rho 1 currents showed very little desensitization, were blocked by picrotoxin but not by bicuculline, and were not modulated by barbiturates, benzodiazepines, or beta-carbolines. Zn2+ reversibly decreased GABA rho 1 responses (IC50 = 22 microM). Other divalent cations were also tested and their rank order of potency was: Zn2+ approximately Ni2+ approximately Cu2+ > Cd2+, whereas Ba2+, Co2+, Sr2+, Mn2+, Mg2+, and Ca2+ showed little or no effect. In contrast, La3+ reversibly potentiated the GABA currents mediated by homomeric GABA rho 1 receptors, with an EC50 = 135 microM and a maximal potentiation of about 100% (GABA, 1 microM; La3+, 1 mM). Other lanthanides showed similar effects (Lu3+ > Eu3+ > Tb3+ > Gd3+ > Er3% > Nd3+ > La3+ > Ce3+). Thus, GABA rho 1 receptors contain sites for cationic recognition, and in particular, Zn2+ may play a role during synaptic transmission in the retina.
Assaf,
Release of endogenous Zn2+ from brain tissue during activity.
, Pubmed
Assaf,
Release of endogenous Zn2+ from brain tissue during activity.
,
Pubmed
Barbacid,
ras genes.
1987,
Pubmed
Bowery,
GABAB receptor pharmacology.
1993,
Pubmed
Buss,
Direct identification of palmitic acid as the lipid attached to p21ras.
1986,
Pubmed
Buss,
Activation of the cellular proto-oncogene product p21Ras by addition of a myristylation signal.
1989,
Pubmed
Capon,
Activation of Ki-ras2 gene in human colon and lung carcinomas by two different point mutations.
,
Pubmed
Casey,
p21ras is modified by a farnesyl isoprenoid.
1989,
Pubmed
Celentano,
Negative modulation of the gamma-aminobutyric acid response by extracellular zinc.
1991,
Pubmed
Cepko,
Construction and applications of a highly transmissible murine retrovirus shuttle vector.
1984,
Pubmed
Chelsky,
A diffusion assay for detection and quantitation of methyl-esterified proteins on polyacrylamide gels.
1984,
Pubmed
Clarke,
Posttranslational modification of the Ha-ras oncogene protein: evidence for a third class of protein carboxyl methyltransferases.
1988,
Pubmed
Cox,
Specific isoprenoid modification is required for function of normal, but not oncogenic, Ras protein.
1992,
Pubmed
Cutting,
Cloning of the gamma-aminobutyric acid (GABA) rho 1 cDNA: a GABA receptor subunit highly expressed in the retina.
1991,
Pubmed
,
Xenbase
Der,
Biological and biochemical properties of human rasH genes mutated at codon 61.
1986,
Pubmed
Dodge,
Strontium and quantal release of transmitter at the neuromuscular junction.
1969,
Pubmed
Draguhn,
Functional and molecular distinction between recombinant rat GABAA receptor subtypes by Zn2+.
1990,
Pubmed
Egan,
The pathway to signal achievement.
1993,
Pubmed
Feig,
The many roads that lead to Ras.
1993,
Pubmed
Feigenspan,
Pharmacology of GABA receptor Cl- channels in rat retinal bipolar cells.
1993,
Pubmed
Furth,
Monoclonal antibodies to the p21 products of the transforming gene of Harvey murine sarcoma virus and of the cellular ras gene family.
1982,
Pubmed
Gutierrez,
Post-translational processing of p21ras is two-step and involves carboxyl-methylation and carboxy-terminal proteolysis.
1989,
Pubmed
Hancock,
A CAAX or a CAAL motif and a second signal are sufficient for plasma membrane targeting of ras proteins.
1991,
Pubmed
Hancock,
All ras proteins are polyisoprenylated but only some are palmitoylated.
1989,
Pubmed
Hancock,
A polybasic domain or palmitoylation is required in addition to the CAAX motif to localize p21ras to the plasma membrane.
1990,
Pubmed
Higuchi,
A general method of in vitro preparation and specific mutagenesis of DNA fragments: study of protein and DNA interactions.
1988,
Pubmed
Howell,
Stimulation-induced uptake and release of zinc in hippocampal slices.
,
Pubmed
Huang,
Plasma membrane-targeted ras GTPase-activating protein is a potent suppressor of p21ras function.
1993,
Pubmed
Im,
Interaction of La3+ with GABAA receptors in rat cerebrocortical membranes as detected with [35S]t-butylbicyclophosphorothionate binding.
1993,
Pubmed
Im,
Selective potentiation of GABA-mediated Cl- current by lanthanum ion in subtypes of cloned GABAA receptors.
1992,
Pubmed
Jackson,
Farnesol modification of Kirsten-ras exon 4B protein is essential for transformation.
1990,
Pubmed
James,
Benzodiazepine peptidomimetics: potent inhibitors of Ras farnesylation in animal cells.
1993,
Pubmed
Kohl,
Selective inhibition of ras-dependent transformation by a farnesyltransferase inhibitor.
1993,
Pubmed
Kusama,
Pharmacology of GABA rho 1 and GABA alpha/beta receptors expressed in Xenopus oocytes and COS cells.
1993,
Pubmed
,
Xenbase
Kusama,
GABA rho 2 receptor pharmacological profile: GABA recognition site similarities to rho 1.
1993,
Pubmed
,
Xenbase
Kusano,
Cholinergic and catecholaminergic receptors in the Xenopus oocyte membrane.
1982,
Pubmed
,
Xenbase
Lacal,
Transforming activity of ras proteins translocated to the plasma membrane by a myristoylation sequence from the src gene product.
1988,
Pubmed
Legendre,
Noncompetitive inhibition of gamma-aminobutyric acidA channels by Zn.
1991,
Pubmed
Lukasiewicz,
A novel GABA receptor on bipolar cell terminals in the tiger salamander retina.
1994,
Pubmed
,
Xenbase
Lukasiewicz,
A novel GABA receptor modulates synaptic transmission from bipolar to ganglion and amacrine cells in the tiger salamander retina.
1994,
Pubmed
Ma,
Differential modulation of GABAA receptor-channel complex by polyvalent cations in rat dorsal root ganglion neurons.
1993,
Pubmed
Magee,
Protein modification. Sticky fingers and CAAX boxes.
1988,
Pubmed
Magee,
Dynamic fatty acylation of p21N-ras.
1987,
Pubmed
Matthews,
Presynaptic inhibition by GABA is mediated via two distinct GABA receptors with novel pharmacology.
1994,
Pubmed
Mayer,
The action of zinc on synaptic transmission and neuronal excitability in cultures of mouse hippocampus.
1989,
Pubmed
McCormick,
Signal transduction. How receptors turn Ras on.
1993,
Pubmed
Miledi,
Effects of defolliculation on membrane current responses of Xenopus oocytes.
1989,
Pubmed
,
Xenbase
Miledi,
Effects of strontium ions on end-plate channel properties.
1980,
Pubmed
Nakanishi,
Multivalent control of 3-hydroxy-3-methylglutaryl coenzyme A reductase. Mevalonate-derived product inhibits translation of mRNA and accelerates degradation of enzyme.
1988,
Pubmed
Nakano,
Expression of the Kirsten ras viral and human proteins in Escherichia coli.
1987,
Pubmed
Olsen,
Molecular biology of GABAA receptors.
1990,
Pubmed
Polenzani,
Expression of mammalian gamma-aminobutyric acid receptors with distinct pharmacology in Xenopus oocytes.
1991,
Pubmed
,
Xenbase
Qian,
Novel GABA responses from rod-driven retinal horizontal cells.
1993,
Pubmed
Reichling,
Lanthanum actions on excitatory amino acid-gated currents and voltage-gated calcium currents in rat dorsal horn neurons.
1991,
Pubmed
Reiss,
Inhibition of purified p21ras farnesyl:protein transferase by Cys-AAX tetrapeptides.
1990,
Pubmed
Sanger,
DNA sequencing with chain-terminating inhibitors.
1977,
Pubmed
Schaber,
Polyisoprenylation of Ras in vitro by a farnesyl-protein transferase.
1990,
Pubmed
Schafer,
Genetic and pharmacological suppression of oncogenic mutations in ras genes of yeast and humans.
1989,
Pubmed
,
Xenbase
Seeburg,
The GABAA receptor family: molecular and functional diversity.
1990,
Pubmed
Shimada,
gamma-Aminobutyric acid A or C receptor? gamma-Aminobutyric acid rho 1 receptor RNA induces bicuculline-, barbiturate-, and benzodiazepine-insensitive gamma-aminobutyric acid responses in Xenopus oocytes.
1992,
Pubmed
,
Xenbase
Shimizu,
Structure of the Ki-ras gene of the human lung carcinoma cell line Calu-1.
,
Pubmed
Smart,
A novel effect of zinc on the lobster muscle GABA receptor.
1982,
Pubmed
Smart,
A novel modulatory binding site for zinc on the GABAA receptor complex in cultured rat neurones.
1992,
Pubmed
Smart,
GABAA receptors are differentially sensitive to zinc: dependence on subunit composition.
1991,
Pubmed
Smart,
Differential effect of zinc on the vertebrate GABAA-receptor complex.
1990,
Pubmed
Trahey,
Molecular cloning of two types of GAP complementary DNA from human placenta.
1988,
Pubmed
Valencia,
The ras protein family: evolutionary tree and role of conserved amino acids.
1991,
Pubmed
Westbrook,
Micromolar concentrations of Zn2+ antagonize NMDA and GABA responses of hippocampal neurons.
,
Pubmed
Willumsen,
Harvey murine sarcoma virus p21 ras protein: biological and biochemical significance of the cysteine nearest the carboxy terminus.
1984,
Pubmed
Woodward,
Effects of steroids on gamma-aminobutyric acid receptors expressed in Xenopus oocytes by poly(A)+ RNA from mammalian brain and retina.
1992,
Pubmed
,
Xenbase
Woodward,
Effects of fenamates and other nonsteroidal anti-inflammatory drugs on rat brain GABAA receptors expressed in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Woodward,
Effects of hexachlorocyclohexanes on gamma-aminobutyric acid receptors expressed in Xenopus oocytes by RNA from mammalian brain and retina.
1992,
Pubmed
,
Xenbase
Woodward,
Characterization of bicuculline/baclofen-insensitive gamma-aminobutyric acid receptors expressed in Xenopus oocytes. I. Effects of Cl- channel inhibitors.
1992,
Pubmed
,
Xenbase
Woodward,
Characterization of bicuculline/baclofen-insensitive (rho-like) gamma-aminobutyric acid receptors expressed in Xenopus oocytes. II. Pharmacology of gamma-aminobutyric acidA and gamma-aminobutyric acidB receptor agonists and antagonists.
1993,
Pubmed
,
Xenbase
Wu,
Localization and modulatory actions of zinc in vertebrate retina.
1993,
Pubmed
Xie,
Properties of GABA-mediated synaptic potentials induced by zinc in adult rat hippocampal pyramidal neurones.
1993,
Pubmed
