GABAA receptor β1, β2, and β3 subunits: comparisons in DBA/2J and C57BL/6J mice

Abstract GABA A receptors link binding of GABA (γ-aminobutyric acid) to inhibitory chloride flux in the brain. They are the site of action of several important classes of drugs, and have been implicated in animal models of epilepsy and in the actions of alcohol. We compare the sequence and expression of the β1, β2 and β3 subunits of GABA A receptors in two inbred strains of mice, DBA/2J and C57BL/6J, which differ markedly in seizure susceptibility and in a variety of behaviors related to alcohol. Only the β3 3 subunit had strain differences in cDNA nucleotide sequence, which did not affect amino acid sequence but which did create restriction fragment length polymorphisms (RFLPs) potentially useful in gene mapping. We have also tested mouse β1 and β2 subunits for internal alternative splicing, detecting none.