title: Exploring the ATP-binding site of P2X receptors.
abstract: P2X receptors are ATP-gated non-selective cation channels involved in many different physiological processes, such as synaptic transmission, inflammation, and neuropathic pain. They form homo- or heterotrimeric complexes and contain three ATP-binding sites in their extracellular domain. The recent determination of X-ray structures of a P2X receptor solved in two states, a resting closed state and an ATP-bound, open-channel state, has provided unprecedented information not only regarding the three-dimensional shape of the receptor, but also on putative conformational changes that couple ATP binding to channel opening. These data provide a structural template for interpreting the huge amount of functional, mutagenesis, and biochemical data collected during more than fifteen years. In particular, the interfacial location of the ATP binding site and ATP orientation have been successfully confirmed by these structural studies. It appears that ATP binds to inter-subunit cavities shaped like open jaws, whose tightening induces the opening of the ion channel. These structural data thus represent a firm basis for understanding the activation mechanism of P2X receptors.
authors.affiliation: Equipe de Chimie et Neurobiologie Moléculaire, Laboratoire de Conception et Application de Molécules Bioactives, Faculté de Pharmacie, UMR 7199 CNRS, Université de Strasbourg Illkirch, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Chataigneau
authors.affiliation: Equipe de Chimie et Neurobiologie Moléculaire, Laboratoire de Conception et Application de Molécules Bioactives, Faculté de Pharmacie, UMR 7199 CNRS, Université de Strasbourg Illkirch, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Lemoine
authors.affiliation: Equipe de Chimie et Neurobiologie Moléculaire, Laboratoire de Conception et Application de Molécules Bioactives, Faculté de Pharmacie, UMR 7199 CNRS, Université de Strasbourg Illkirch, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Grutter
keywords: ATP; P2X receptors; binding site; crystal structure; engineered site-directed labeling; gating; mutagenesis