Recent advances and perceptions in studies of heterodimerization between G protein-coupled receptors

G pretein coupled-receptors (GPCR) have been shown to form heterodimers or heterooligomers with various biochemical and/or pharmacological activity that are distinct from those of the corresponding monomers or homomers. Recent in vitro and in vivo experimental data have also shown novel functional roles of several orphan GPCRs as modulatory units of heterodimers and potentials for development of heterodimer-selective clinical agents. In this review, we summarize essential and latest knowledge as to GPCR heterodimerizations and the current issues to be solved in the near future.