GABA (gamma-amino butyric acid) receptors belong to the group of pentameric ligand-gated ion channels as serotonin receptors or acetylcholin receptors. Since these membrane proteins have been impossible to chrystallize for a long time and there are still difficulties to determine their structure by X-ray spectometry. However, in recent years it became fashionable to analyze membrane receptors of different types, the determination of the GABA receptor is not a great surprise.
In this week Nature (doi:10.1038/nature13293) Miller and Aricescu from Oxford, UK, show the structure of the so-called β3-homopentamer. BTW that only two authors succeded in this task comes as a surprise.
The GABA receptor is involved in a number of diseases: epilepsy, insomnia, anxiety and panic disorders, has a role in alcohol abuse, binds to benzodiapines. Miller and Aricescu have chrystallized the receptor with a so far unkown agonist (a molecule to activate): benzamidine which allows predictions about the way ligands are bound and how they function.
The paper shows a abundance of beautiful structural graphs which were drawn with Pymol a nice program used by myself in Hormone und Hormonsystem.