Laurence Jacquemart, Bernd Hutter
Berthold technologies, Bad Wildbad, Germany. Cisbio Bioassays, Codolet, France.
GPCRs carry information within cells via two major signaling pathways: regulation of cAMPlevels and increases in intracellular Ca2+ triggered by inositol (1,4,5) tri-phosphate (IP3). These signaling pathways are activated by the specific G protein associated with the receptor. Gs and Gi coupled receptors result in variations of cAMP while Gq coupled GPCRs activate phospholipase C (PLC) and trigger the inositol phosphate (IP) cascade. Cisbio Bioassays developed a full line of quality, ready-to-use kits capable of monitoring activation of Gs, Gi and Gq coupled receptors and recently introduced a new generation of HTRF technology incorporating Lumi4-Tb™, a new TR-FRET terbium Cryptate. Thanks to this chemistry, detection of two events at the same time in one well became possible by using 2 different acceptors a green dye (cwl = 520 nm) and a red dye (cwl = 665 nm)