The dynamic nature of neurotensin receptor 1 (NTS1) allostery and signaling bias

Bumbak, F.; Inoue, A.; Pons, M.; Paniagua, J. C.; Yan, F.; Wu, H.; ROBSON, S. A.; Bathgate, R. A. D.; Scott, D. J.; Gooley, P. R.; Ziarek, J. J.

doi:10.1101/2022.11.25.517797

bioRxiv · 10.1101/2022.11.25.517797

The dynamic nature of neurotensin receptor 1 (NTS1) allostery and signaling bias

Bumbak, F.·Inoue, A.·Pons, M.·Paniagua, J. C.·Yan, F.·Wu, H.·ROBSON, S. A.·Bathgate, R. A. D.·Scott, D. J.·Gooley, P. R.·Ziarek, J. J.

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Abstract

The neurotensin receptor 1 (NTS1) is a G protein-coupled receptor (GPCR) with promise as a drug target for the treatment of pain, schizophrenia, obesity, addiction, and various cancers. A detailed picture of the NTS1 structural landscape has been established by X-ray crystallography and cryo-EM and yet, the molecular determinants for why a receptor couples to G protein versus arrestin transducers remain poorly defined. We used 13C{varepsilon}H3-methionine NMR spectroscopy to show that phosphatidylinositol-4,5-bisphosphate (PIP2) promotes transducer complexation not by dramatically altering the receptor structure but by strengthening long-range allosteric connections, in the form of correlated conformational kinetics, between the orthosteric pocket and highly-conserved activation motifs. {beta}-arrestin-1 further remodels the receptor ensemble by reducing conformational exchange kinetics for a subset of resonances, whereas G protein coupling has little to no effect on the rate. A {beta}-arrestin biased allosteric modulator transforms the NTS1:G protein complex into a concatenation of substates, without triggering transducer dissociation, suggesting that it may function by stabilizing signaling incompetent G protein conformations such as the non-canonical state. Together, our work demonstrates the importance of kinetic information to a complete picture of the GPCR activation landscape.

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Bumbak, F., Inoue, A., Pons, M., Paniagua, J. C., Yan, F., Wu, H., ROBSON, S. A., Bathgate, R. A. D., Scott, D. J., Gooley, P. R., Ziarek, J. J.. 2022-11-27. The dynamic nature of neurotensin receptor 1 (NTS1) allostery and signaling bias. https://doi.org/10.1101/2022.11.25.517797

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