Assembly of N-methyl-D-aspartate (NMDA) receptors.

The N-methyl-D-aspartate receptor (NMDAR) requires both NR1 and NR2 subunits to form a functional ion channel. Despite the recent advances in our understanding of the contributions of these different subunits to both the function and pharmacology of the NMDAR, the precise subunit stoichiometry of the receptor and the regions of the subunits governing subunit interactions remain unclear. Since NR2 subunits are not transported to the cell surface unless they associate with NR1 subunits, cell-surface expression of NR2A can be used to monitor the association of the different subunits in cells transfected with N- and C-terminally truncated NR1 subunits.

Gene expression profiling of drug metabolism and toxicology markers using a low-density DNA microarray.

DNA microarrays are useful tools to study changes of gene expression in response to a treatment with drugs. Here, we describe the optimization of conditions for the cDNA synthesis and hybridization protocols to be used for a low-density DNA microarray called 'Rat HepatoChips.' This DNA microarray with 59 carefully selected genes could be used to study changes in gene expression levels due to a treatment with xenobiotic.

Identification of molecular determinants that are important in the assembly of N-methyl-D-aspartate receptors.

To determine which domains of the N-methyl-d-aspartate (NMDA) receptor are important for the assembly of functional receptors, a number of N- and C-terminal truncations of the NR1a subunit have been produced. Truncations containing a complete ligand binding domain bound glycine antagonist and gave binding constants similar to those of the native subunit, suggesting they were folding to form antagonist binding sites. Since NR2A is not transported to the cell surface unless it is associated with NR1 (McIlhinney, R.

theta, a novel gamma-aminobutyric acid type A receptor subunit.

gamma-Aminobutyric acid type A (GABA-A) receptors are a major mediator of inhibitory neurotransmission in the mammalian central nervous system, and the site of action of a number of clinically important drugs. These receptors exist as a family of subtypes with distinct temporal and spatial patterns of expression and distinct properties that presumably underlie a precise role for each subtype. The newest member of this gene family is the theta subunit.

Molecular and functional diversity of the expanding GABA-A receptor gene family.

Fast inhibitory neurotransmission in the mammalian CNS is mediated primarily by the neurotransmitter gamma-aminobutyric acid (GABA), which, upon binding to its receptor, leads to opening of the intrinsic ion channel, allowing chloride to enter the cell. Over the past 10 years it has become clear that a family of GABA-A receptor subtypes exists, generated through the coassembly of polypeptides selected from alpha 1-alpha 6, beta 1-beta 3, gamma 1-gamma 3, delta, epsilon, and pie to form what is most likely a pentomeric macromolecule. The gene transcripts, and indeed the polypeptides, show distinct patterns of temporal and spatial expression, such that the GABA-A receptor subtypes have a defined localization that presumably reflects their physiological role.