Cannabinoid CB(1) receptor ligand binding and function examined through mutagenesis studies of F200 and S383.
The cannabinoid CB(1) G protein-coupled receptor has been shown to be a regulator of food consumption and has been studied extensively as a drug target for the treatment of obesity. To advance understanding of the receptor's three-dimensional structure, we performed mutagenesis studies at human cannabinoid CB(1) receptor residues F200 and S383 and measured changes in activity and binding affinity of compounds from two recently discovered active chemotypes, arylsulfonamide agonists and tetrahydroquinoline-based inverse agonists, as well as literature compounds. Our results add support to previous findings that both agonists and inverse agonists show varied patterns of binding at the two mutated residue sites, suggesting multiple subsites for binding to the cannabinoid CB(1) receptor for both functional types of ligands. We additionally find that an F200L mutation in the receptor largely restores binding affinity to ligands and significantly decreases constitutive activity when compared to F200A, resulting in a receptor phenotype that is closer to the wild-type receptor. The results downplay the importance of aromatic stacking interactions at F200 and suggest that a bulky hydrophobic contact is largely sufficient to provide significant receptor function and binding affinity to cannabinoid CB(1) receptor ligands.
Research and Development, Bristol-Myers Squibb Company, Princeton, NJ 08543-5400, USA. doree.sitkoff@bms.com
Doree F
DF
Sitkoff
Ning
N
Lee
Bruce A
BA
Ellsworth
Qi
Q
Huang
Liya
L
Kang
Roseann
R
Baska
Yanting
Y
Huang
Chongqing
C
Sun
Annapurna
A
Pendri
Mary F
MF
Malley
Raymond P
RP
Scaringe
Jack Z
JZ
Gougoutas
Patricia H
PH
Reggio
William R
WR
Ewing
Mary Ann
MA
Pelleymounter
Kenneth E
KE
Carlson
D000818:Animals; D001565:Benzoates / Q000378:metabolism / Q000494:pharmacology; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D054314:Drug Inverse Agonism; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008024:Ligands; D016296:Mutagenesis; D010649:Phenylalanine / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D011804:Quinolines / Q000378:metabolism / Q000494:pharmacology; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D012694:Serine / Q000235:genetics / Q000378:metabolism; D013449:Sulfonamides / Q000378:metabolism / Q000494:pharmacology
C519013:8-quinolinyl 4-methyl-3-(1-piperidinylsulfonyl)benzoate; D001565:Benzoates; D008024:Ligands; D016271:Proto-Oncogene Proteins c-myc; D011804:Quinolines; D043884:Receptor, Cannabinoid, CB1; D013449:Sulfonamides; D012694:Serine; D010649:Phenylalanine; C542964:1,2,3,4-tetrahydroquinoline