Engineering a GPCR-ligand pair that simulates the activation of D(2L) by Dopamine.
In the past decade, engineered G-protein-coupled receptors activated solely by synthetic ligands (RASSLs) have been implemented as a new means to study neurotransmission, which is controlled by G-protein-coupled receptors in vitro and in vivo. In this study, we report an engineered dopamine receptor D(2L) F390(6.52)W, which is the first identified RASSL for the dopamine receptor family. The mutant receptor is characterized by a disrupted ligand binding and complete loss of efficacy for the endogenous ligand, dopamine, which is putatively due to a sterically induced perturbation of H-bonding with conserved serine residues in TM5. Based on this model, we rationally developed an aminoindane-derived set of agonists. Because these agonists forgo analogous H-bonding functionalities, their binding energy does not depend on the respective interactions. Binding affinity and potency were optimized by ligand modifications bearing molecular appendages that obviously interact with a secondary recognition site provided by four hydrophobic residues in TM2 and TM3. Thus, the ferrocenyl carboxamide 5b (FAUC 185) was identified as a synthetic agonist that is able to stimulate the mutant receptor in a manner similar to that by which endogenous dopamine activates the D(2L) wild-type receptor. The engineered dopamine receptor D(2L) F390(6.52)W in combination with FAUC 185 (5b) provides a new tool to probe GPCR functions selectively in specific cell populations in vitro and in vivo.
Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, D-91052 Erlangen, Germany.
Nuska
N
Tschammer
Miriam
M
Dörfler
Harald
H
Hübner
Peter
P
Gmeiner
D000818:Animals; D016466:CHO Cells; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D003001:Cloning, Molecular; D006224:Cricetinae; D003412:Cricetulus; D000242:Cyclic AMP / Q000096:biosynthesis; D015195:Drug Design; D004797:Enzyme-Linked Immunosorbent Assay; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007202:Indicators and Reagents; D008024:Ligands; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D017448:Receptors, Dopamine D2 / Q000737:chemistry* / Q000235:genetics*; D043562:Receptors, G-Protein-Coupled / Q000819:agonists / Q000737:chemistry* / Q000235:genetics*; D013329:Structure-Activity Relationship
D007202:Indicators and Reagents; D008024:Ligands; D017448:Receptors, Dopamine D2; D043562:Receptors, G-Protein-Coupled; C113776:dopamine D2L receptor; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D000242:Cyclic AMP