Structure of the active G i -coupled human lysophosphatidic acid receptor 1 complexed with a potent agonist.

Lysophosphatidic acid receptor 1 (LPA 1 ) is one of the six G protein-coupled receptors activated by the bioactive lipid, lysophosphatidic acid (LPA). LPA 1 is a drug target for various diseases, including cancer, inflammation, and neuropathic pain. Notably, LPA 1 agonists have potential therapeutic value for obesity and urinary incontinence. Here, we report a cryo-electron microscopy structure of the active human LPA 1 -G i complex bound to ONO-0740556, an LPA analog with more potent activity against LPA 1 . Our structure elucidated the details of the agonist binding mode and receptor activation mechanism mediated by rearrangements of transmembrane segment 7 and the central hydrophobic core. A structural comparison of LPA 1 and other phylogenetically-related lipid-sensing GPCRs identified the structural determinants for lipid preference of LPA 1 . Moreover, we characterized the structural polymorphisms at the receptor-G-protein interface, which potentially reflect the G-protein dissociation process. Our study provides insights into the detailed mechanism of LPA 1 binding to agonists and paves the way toward the design of drug-like agonists targeting LPA 1 .