G protein-coupled receptors (GPCRs) constitute one of the most important pharmaceutical targets, in particular for the treatment of disorders of the central nervous system (CNS). GPCR-modulating drugs, however, exhibit a varying efficiency. They usually focus on individual GPCRs. During the last decades, several studies have shown that GPCRs may interact with each other and so receptor mosaics (gay or heterodimer / oligomeric) are able to form. A thorough understanding of the contribution of this receptor mosaics at the onset and the development of aandoeiningen of the CNS, and as a potential therapeutic target requires further investigation. The development of drugs directed against the GPCR oligomers (among other things, bivalent drugs) can therefore provide a therapeutically significant added value by a greater specificity. This research project aims to gain a better understanding of the molecular basis of such GPCR heterodimers with a focus on acetylcholine (M1), dopamine (D2) and glutamate (mGluR5) receptors given their importance in signaling in the CNS.