Dataset Information

Mutation of a zinc-binding residue in the glycine receptor ?1 subunit changes ethanol sensitivity in vitro and alcohol consumption in vivo.

ABSTRACT: Ethanol is a widely used drug, yet an understanding of its sites and mechanisms of action remains incomplete. Among the protein targets of ethanol are glycine receptors (GlyRs), which are potentiated by millimolar concentrations of ethanol. In addition, zinc ions also modulate GlyR function, and recent evidence suggests that physiologic concentrations of zinc enhance ethanol potentiation of GlyRs. Here, we first built a homology model of a zinc-bound GlyR using the D80 position as a coordination site for a zinc ion. Next, we investigated in vitro the effects of zinc on ethanol action at recombinant wild-type (WT) and mutant ?1 GlyRs containing the D80A substitution, which eliminates zinc potentiation. At D80A GlyRs, the effects of 50 and 200 mM ethanol were reduced as compared with WT receptors. Also, in contrast to what was seen with WT GlyRs, neither adding nor chelating zinc changed the magnitude of ethanol enhancement of mutant D80A receptors. Next, we evaluated the in vivo effects of the D80A substitution by using heterozygous Glra1(D80A) knock-in (KI) mice. The KI mice showed decreased ethanol consumption and preference, and they displayed increased startle responses compared with their WT littermates. Other behavioral tests, including ethanol-induced motor incoordination and strychnine-induced convulsions, revealed no differences between the KI and WT mice. Together, our findings indicate that zinc is critical in determining the effects of ethanol at GlyRs and suggest that zinc binding at the D80 position may be important for mediating some of the behavioral effects of ethanol action at GlyRs.

SUBMITTER: McCracken LM

PROVIDER: S-EPMC3558822 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mutation of a zinc-binding residue in the glycine receptor α1 subunit changes ethanol sensitivity in vitro and alcohol consumption in vivo.

McCracken Lindsay M LM Blednov Yuri A YA Trudell James R JR Benavidez Jillian M JM Betz Heinrich H Harris R Adron RA

The Journal of pharmacology and experimental therapeutics 20121210 2

Ethanol is a widely used drug, yet an understanding of its sites and mechanisms of action remains incomplete. Among the protein targets of ethanol are glycine receptors (GlyRs), which are potentiated by millimolar concentrations of ethanol. In addition, zinc ions also modulate GlyR function, and recent evidence suggests that physiologic concentrations of zinc enhance ethanol potentiation of GlyRs. Here, we first built a homology model of a zinc-bound GlyR using the D80 position as a coordination ...[more]

PMID: 23230213

Similar Datasets

Project description:This study investigated changes in gene expression associated with ethanol drinking in adult male P rats under the following conditions for 8 weeks: continuous access (24 hr/day, 7 days/week), multiple scheduled access (three 1-hr sessions during the dark cycle/day, 5 days/week) and ethanol-naive (water). The objective of this study was to investigate changes in gene expression associated with ethanol drinking. Adult male alcohol-preferring (P) rats were given Ethanol in their home-cages under continuous access (CA; 24 hr/day, 7 days/week) or multiple scheduled access (MSA; three 1-hr sessions during the dark cycle/day, 5 days/week) conditions for 8 weeks. A third group was ethanol-naÃÂ¯ve (W group). Average ethanol intakes, across the 8 weeks, for the CA and MSA groups were approximately 9.5 and 6.5 g/kg/day, respectively. Fifteen hr after the last ethanol drinking episode, rats were euthanized, the brains rapidly extracted, and the nucleus accumbens (ACB) dissected. RNA was extracted and purified for microarray analysis. The only significant differences, overall, were between the CA and W groups (p < 0.01; Storey false discovery rate = 0.15); there were 374 significant differences in unique named genes between these 2 groups. There were 20 significant Gene Ontology (GO) biological processes categories, which included Ã¢ÂÂnegative regulation of protein kinase activityÃ¢ÂÂ, Ã¢ÂÂanti-apoptosisÃ¢ÂÂ, and Ã¢ÂÂregulation of G-protein-coupled receptor protein signaling pathwayÃ¢ÂÂ. IngenuityÃÂ® analysis indicated a network of transcription factors, involving oncogenes (Fos, Jun, Junb had higher expression levels in the ACB of the CA than W group), suggesting increased neuronal activity in the CA group. There were 13 genes (Hspa5, Stom, Lcn7, Tceb3, Cdc42, Rap1ga1, Ece1, Dhrs3, Plod1, Kif1b, Nmnat1, Srpr, Esam) significantly different between the CA and W groups located within both mouse and rat ethanol QTLs, suggesting that these genes may contribute to ethanol drinking behavior. In conclusion, the robust differences in gene expression found between the CA and W groups, but not observed between the MSA and W groups, may be a result of the higher daily ethanol intakes of the CA group, and/or its initial ethanol withdrawal. Experiment Overall Design: 10 samples each of control, continuous ethanol and limited access ethanol

Dataset Information

Mutation of a zinc-binding residue in the glycine receptor ?1 subunit changes ethanol sensitivity in vitro and alcohol consumption in vivo.

Publications

Mutation of a zinc-binding residue in the glycine receptor α1 subunit changes ethanol sensitivity in vitro and alcohol consumption in vivo.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets