biostudies-literatureHarris JAKinship FoundationHuman Frontier Science ProgramDepartment of Education and Training | Australian Research CouncilPew Charitable TrustsNCRR NIH HHSHoward Hughes Medical InstituteDepartment of Health | National Health and Medical Research CouncilNIGMS NIH HHSNIH HHSU.S. Department of Health & Human Services | National Institutes of HealthNational Science FoundationEsther A. and Joseph Klingenstein Fund109-115https://www.ebi.ac.uk/biostudies/studies/S-EPMC8712391biostudies-literatureUnknown18(1)The neuropeptide substance P (SP) is important in pain and inflammation. SP activates the neurokinin-1 receptor (NK1R) to signal via G_q and G_s proteins. Neurokinin A also activates NK1R, but leads to selective G_q signaling. How two stimuli yield distinct G protein signaling at the same G protein-coupled receptor remains unclear. We determined cryogenic-electron microscopy structures of active NK1R bound to SP or the G_q-biased peptide SP6-11. Peptide interactions deep within NK1R are critical for receptor activation. Conversely, interactions between SP and NK1R extracellular loops are required for potent G_s signaling but not G_q signaling. Molecular dynamics simulations showed that these superficial contacts restrict SP flexibNature chemical biologySelective G protein signaling driven by substance P-neurokinin receptor dynamics.PMC8712391DP5 OD023048S10OD021741U24 GM129541DP5OD023048R01 GM127359S10OD020054APP1196951S10 RR026814APP1138448LT000916/2018-LDE170100152R01GM127359S10 OD020054T32 GM0082842034836R35 GM140847S10 OD021741Thal DMGondin ABHarris JAVeldhuis NAManglik AFaust BSuomivuori CMDror ROCheng YDamgen MAfalseSelective G protein signaling driven by substance P-neurokinin receptor dynamics.The neuropeptide substance P (SP) is important in pain and inflammation. SP activates the neurokinin-1 receptor (NK1R) to signal via G_q and G_s proteins. Neurokinin A also activates NK1R, but leads to selective G_q signaling. How two stimuli yield distinct G protein signaling at the same G protein-coupled receptor remains unclear. We determined cryogenic-electron microscopy structures of active NK1R bound to SP or the G_q-biased peptide SP6-11. Peptide interactions deep within NK1R are critical for receptor activation. Conversely, interactions between SP and NK1R extracellular loops are required for potent G_s signaling but not G_q signaling. Molecular dynamics simulations showed that these superficial contacts restrict SP flexib2022-01-01T00:00:00Z2022 Jan2026-05-31T05:02:55.533Z2025-02-19T01:54:27.39ZS-EPMC87123913471198010.1038/s41589-021-00890-8