The modified GPCRs of the present invention include GPCRs that have been modified to have altered DRY motifs such that the modified GPCRs are constitutively desensitized.

There is also provided methods of antagonising or agonising A GPCR in vivo comprising the administration of a GPCR or a polynucleotide encoding a GPCR to a subject.

In addition to isolated, full-length GPCR-like proteins, the invention further provides isolated GPCR-like fusion proteins, antigenic peptides, and anti-GPCR-like antibodies.

This modified arrestin has an increased affinity for a GPCR, and traffics with the GPCR into endosomes.

The present invention is related to the detection of GPCR ligands in a test sample by using a single cell biosensor expressing a GPCR.

Methods of producing GPCRs with increased stability relative to a parent GPCR are also disclosed.

Preferably the GPCR is human.

A method of screening a novel SPC-activated GPCR ligand by using an SPC-activated GPCR and a known SPC-activated GPCR ligand.

The invention further provides a GPCR for use in inhibiting an activity of a GPCR binding partner in a subject.

There is provided a G protein coupled receptor (GPCR) or a polynucleotide encoding said GPCR for use as a vaccine.

In certain embodiments, the GPCR is human.

In certain embodiments, the GPCR is human.

The present invention provides a transgenic cell co-expressing at least one ionic channel and at least one G-protein coupled receptor (GPCR), wherein at least one GPCR signaling pathways is modulated by a GPCR signaling compounds.

Among the ORFs thus obtained, a gene homologous with a known GPCR gene (preferably a gene showing the highest homology with a GPCR gene or a GPCR-associated gene in homology searching) is searched for.

Certain embodiments provide a GPCR fusion protein.