Merck Millipore Membrane Preparation mGLU6 Receptor

Glutamate is a main excitatory neurotransmitter in the central nervous system, and it plays a role in learning, memory and neurotoxicity. The biological actions of glutamate are mediated by ionotropic and metabotropic glutamate receptors, which are ion channels and GPCRs respectively. Metabotropic glutamate receptors (mGluRs) are members of the class 3 G-protein coupled receptor family, which are characterized by a large extracellular domain. They are further classified into group I, II, and III mGluRs on the basis of their sequence identity, pharmacology, and signal transduction mechanism. Group I (mGlu1 and mGlu5) couple to the phospholipase C pathway through Gαq, whereas group II (mGlu2 and mGlu3) and group III (mGlu4, mGlu6, mGlu7, and mGlu8) negatively couple to the adenylyl cyclase pathway though Gαi (Conn and Pin, 1997). mGlu6 has a restricted localization to the dendrites of ON bipolar cells that synapse with retinal rods and cones. Targeted deletion of mGlu6 results in deficits in ON responses but unchanged OFF responses to light (Masu et al., 1995). In addition, mutations in GRM6 in humans are responsible for some forms of autosomal recessive congenital stationary night blindness (Dryja et al., 2005; Zeitz et al., 2005). Chemicon's mGlu6 membrane preparations are crude membrane preparations made from our proprietary stable recombinant cell lines to ensure high-level of GPCR surface expression; thus, they are ideal HTS tools for screening of mGlu6 interactions with its ligands. The cell line exhibits a calcium response with EC50s of 6.2 µM, 23.4 µM, and 52.7 µM for L-AP4, (RS)PPG, and L-glutamate. The membrane preparations exhibit EC50s of of 4.0 µM, 24.1 µM, and 49.3 µM for L-AP4, (RS)PPG, and L-glutamate, respectively, in a GTPγS binding assay.