Neurotensin receptors are transmembrane receptors that bind the neurotransmitterneurotensin.[1][2] Two of the receptors encoded by the NTSR1 and NTSR2 genes contain seven transmembrane helices and are G protein coupled. Numerous crystal structures have been reported for the neurotensin receptor 1 (NTS1).[3] The third receptor has a single transmembrane domain and is encoded by the SORT1 gene.
Unusually for GPCRs, NTS1 can be expressed in an active form in the bacteria E. coli.[8] It can be purified and analysed in vitro and has been analysed by a number of biophysical techniques such as surface plasmon resonance,[9] FRET[10] and cryo-electron microscopy.[11]
Furthermore, high-resolution crystal structures of NTS1 have been determined in complex with the peptide full agonist NT8-13, the non-peptide full agonist SRI-9829, the partial agonist RTI-3a, and the antagonists / inverse agonists SR-48692 and SR-142948, as well as in the ligand-free apo state [3]
