Anxiety over GABA(A) receptor structure relieved by AChBP.

The GABA(A) receptor is the primary mediator of inhibitory neurotransmission in the brain and is a major target for neuromodulatory drugs such as benzodiazepines, barbiturates, ethanol and anaesthetics. However, our understanding of the molecular details of this receptor has been limited by a lack of high-resolution structural information. This article presents a new model for the extracellular, ligand-binding domain of the GABA(A) receptor, that is based on the recently determined structure of a soluble acetylcholine-binding protein. The model puts existing mutational and biochemical data into a three-dimensional context, shows details of the GABA- and benzodiazepine-binding sites, and highlights the importance of other regions in allosteric conformational change. This provides a new perspective on existing data and an exciting new framework for understanding this important family of receptors.

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