Cryo-EM structure of cell-free synthesized human histamine H2 receptor coupled to heterotrimeric Gs protein in lipid nanodisc environment

Zoe Köck, Kilian Schnelle, Margherita Persechino, Simon Umbach, Hannes Schihada, Dovile Januliene, Kristian Parey, Steffen Pockes, Peter Kolb, Volker Dötsch, Arne
Möller, Daniel Hilger, Frank Bernhard

Here we describe the cryo-electron microscopy structure of the human histamine 2 receptor (H₂R) in an active conformation with bound histamine and in complex with G_s heterotrimeric protein at an overall resolution of 3.4 Å. The complex was generated by cotranslational insertion into preformed nanodisc membranes using cell-free synthesis in E. coli lysates. It is the first structure obtained by this detergent-free strategy and the first GPCR/G_s complex structure in lipid environment. Structural comparison with the inactive conformation of H₂R and the inactive and G_q-coupled active state of H₁R together with structure-guided functional experiments reveal molecular insights into the specificity of ligand binding and G protein coupling for this receptor family. We demonstrate lipid-modulated folding of cell-free synthesized H₂R, its agonist-dependent internalization and its interaction with endogenously synthesized H₁R and H₂R in HEK293 cells by applying a recently developed nanotransfer technique.

DOI: https://doi.org/10.1038/s41467-024-46096-z

PMID: 38418462