Structural basis of hydroxycarboxylic acid receptor signaling mechanisms through ligand binding

Cryo-EM structures of HCA2 and HCA3–Gi complexes with different agonists

We generated HCA2 and HCA3 constructs with thermostabilized apocytochrome b562RIL (bRIL) conjugated at the N-terminus of the receptors and, for HCA2, fused the receptor to the large NanoBiT subunit (LgBiT) to stabilize the complex (NanoBiT tethering strategy^20,21). These modifications had little effect on the pharmacologic properties of HCA2 and HCA3 (Supplementary Fig. 1). The receptor, Gi, Gβγ subunits, and scFv16 were co-expressed in Sf9 insect cells and then incubated with chemically different agonists for…