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

Koeck, Z.; Schnelle, K.; Persechino, M.; Umbach, S.; Schihada, H.; Januliene, D.; Parey, K.; Pockes, S.; Kolb, P.; Doetsch, V.; Moeller, A.; Hilger, D.; Bernhard, F.

doi:10.1101/2023.07.27.550782

bioRxiv · 10.1101/2023.07.27.550782

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

Koeck, Z.·Schnelle, K.·Persechino, M.·Umbach, S.·Schihada, H.·Januliene, D.·Parey, K.·Pockes, S.·Kolb, P.·Doetsch, V.·Moeller, A.·Hilger, D.·Bernhard, F.

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Abstract

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 Gs heterotrimeric protein at an overall resolution of 3.4 [A]. 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/Gs complex structure in lipid environment. Structural comparison with the inactive conformation of H2R and the inactive and Gq-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.

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Koeck, Z., Schnelle, K., Persechino, M., Umbach, S., Schihada, H., Januliene, D., Parey, K., Pockes, S., Kolb, P., Doetsch, V., Moeller, A., Hilger, D., Bernhard, F.. 2023-07-27. Cryo-EM structure of cell-free synthesized human histamine H2 receptor coupled to heterotrimeric Gs protein in lipid nanodisc environment. https://doi.org/10.1101/2023.07.27.550782

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