title: Dopamine D2 receptor signaling dynamics of dopamine D2-neurotensin 1 receptor heteromers.
abstract: Biochemical, histochemical and coimmunoprecipitation experiments have indicated the existence of antagonistic dopamine D2 (D2R) and neurotensin 1 (NTS1R) receptor-receptor interactions in the dorsal and ventral striatum indicating a potential role of these receptor-receptor interactions in Parkinson's disease and schizophrenia. By means of Bioluminiscence Resonance energy transfer (BRET(2)) evidence has for the first time been obtained in the current study for the existence of both D2LR/NTS1R and D2SR/NTS1R heteromers in living HEK293T cells. Through confocal laser microscopy the NTS1R(GFP2) and D2R(YFP) were also shown to be colocated in the plasma membrane of these cells. A bioinformatic analysis suggests the existence of a basic set of three homology protriplets (TVM, DLL and/or LRA) in the two participating receptors which may contribute to the formation of the D2R/NTS1R heteromers by participating in guide-clasp interactions in the receptor interface. The CREB reporter gene assay indicated that the neurotensin receptor agonist JMV 449 markedly reduced the potency of the D2R like agonist quinpirole to inhibit the forskolin induced increase of the CREB signal. In contrast, the neurotensin agonist was found to markedly increase the quinpirole potency to activate the MAPK pathway as also studied with luciferase reporter gene assay measuring the degree of SRE activity as well as with ERK1/2 phosphorylation assays. These dynamic changes in D2R signaling produced by the neurotensin receptor agonist may involve antagonistic allosteric receptor-receptor interactions in the D2LR-NTS1R heteromers at the plasma membrane level (CREB pathway) and synergistic interactions in PKC activation at the cytoplasmatic level (MAPK pathway).
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden. Dasiel.Borroto-Escuela@ki.se
authors.forename: Dasiel O
authors.initials: DO
authors.lastname: Borroto-Escuela
authors.forename: Annalisa
authors.initials: A
authors.lastname: Ravani
authors.forename: Alexander O
authors.initials: AO
authors.lastname: Tarakanov
authors.forename: Ismel
authors.initials: I
authors.lastname: Brito
authors.forename: Manuel
authors.initials: M
authors.lastname: Narvaez
authors.forename: Wilber
authors.initials: W
authors.lastname: Romero-Fernandez
authors.forename: Fidel
authors.initials: F
authors.lastname: Corrales
authors.forename: Luigi F
authors.initials: LF
authors.lastname: Agnati
authors.forename: Sergio
authors.initials: S
authors.lastname: Tanganelli
authors.forename: Luca
authors.initials: L
authors.lastname: Ferraro
authors.forename: Kjell
authors.initials: K
authors.lastname: Fuxe
mesh_terms: D060807:Bioluminescence Resonance Energy Transfer Techniques / Q000379:methods; D002462:Cell Membrane / Q000378:metabolism; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D057809:HEK293 Cells; D006801:Humans; D007700:Kinetics; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D008958:Models, Molecular; D009842:Oligopeptides / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D011720:Pyrazoles / Q000494:pharmacology; D011804:Quinolines / Q000494:pharmacology; D019257:Quinpirole / Q000494:pharmacology; D020891:Raclopride / Q000494:pharmacology; D017448:Receptors, Dopamine D2 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018028:Receptors, Neurotensin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D008164:Luminescent Proteins; D009842:Oligopeptides; D011720:Pyrazoles; D011804:Quinolines; D017448:Receptors, Dopamine D2; D018028:Receptors, Neurotensin; C114947:SR 142948; C114036:neurotensin type 1 receptor; C077827:JMV 449; D019257:Quinpirole; D020891:Raclopride; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3