Homologous sites of GABAA receptor α1, β3 and γ2 subunits are important for assembly

GABA(A) receptors are the major inhibitory transmitter receptors in the central nervous system. The majority of these receptors is composed of two alpha, two beta and one gamma subunit that assemble around an aqueous pore and form an intrinsic chloride ion channel. Using full-length or truncated chimeric subunits it was demonstrated that homologous sequences from different subunit classes, alpha(1)(54-68), beta(3)(52-66), and gamma(2)(67-81), are important for assembly of GABA(A) receptors composed of alpha(1), beta(3), and gamma(2) subunits. In addition, evidence was provided that these sequences all are located in topologically homologous regions of the different subunits. Finally, it was demonstrated that the sequences investigated cause a selective assembly with certain subunits only and thus influence subunit arrangement within GABA(A) receptors. (C) 2002 Elsevier Science Ltd. All rights reserved.