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Elucidation of Mechanism for Ligand Efficacy at Leukotriene B₄ Receptor 2 (BLT2).

ABSTRACT: G protein-coupled receptors (GPCRs) have always been important drug targets in the pharmaceutical industry. One major question for the current GPCR drug discovery is how drugs have distinct efficacies at the same GPCR target. Related to this question, we studied how different ligands can have disparate efficacies at Leukotriene B₄ receptor (BLT2). By using molecular modeling studies, we predicted that Tyr271^6.51 located at TM6 of BLT2 performs as a key trigger for its activation and verified the prediction by site-directed mutagenesis, chemotactic motility studies, which included a chemical derivative of agonist CAY10583. We further identified Asn275^6.55 located at TM6 as a weak activation trigger in BLT2 and performed double mutation studies to confirm our computational results. Our results provide strong evidence for the exact mechanism of ligand efficacy at BLT2.

SUBMITTER: Kim M

PROVIDER: S-EPMC7430951 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Elucidation of Mechanism for Ligand Efficacy at Leukotriene B4 Receptor 2 (BLT2).

Kim Minsup M Wei Jun-Dong JD Harmalkar Dipesh S DS Goo Ja-Il JI Lee Kyeong K Choi Yongseok Y Kim Jae-Hong JH Cho Art E AE

ACS medicinal chemistry letters 20200714 8

G protein-coupled receptors (GPCRs) have always been important drug targets in the pharmaceutical industry. One major question for the current GPCR drug discovery is how drugs have distinct efficacies at the same GPCR target. Related to this question, we studied how different ligands can have disparate efficacies at Leukotriene B4 receptor (BLT2). By using molecular modeling studies, we predicted that Tyr2716.51 located at TM6 of BLT2 performs as a key trigger for its activ ...[more]

PMID: 32832019

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