Extended Data Fig. 1: Identification of lipids bound to NTSR1(HTGH4-ΔIC3B).
From: PtdIns(4,5)P2 stabilizes active states of GPCRs and enhances selectivity of G-protein coupling
a, Endogenous lipids bound to NTSR1(HTGH4-ΔIC3B), isolated from E. coli, are identified as PA following m/z selection in the mass spectrometry quadrupole of the NTSR1:lipid 11+ charge state (highlighted yellow) and collisional activation to dissociate PA and its homologues (m/z, 700–760 Da). b, Lipidomics analysis of purified NTSR1 with three technical replicates reveals peaks at low m/z. MS/MS spectra of the precursor ion (M-H-1) at m/z 699.32 highlighted yellow, leads to definitive fragment ions at m/z 281 and 417 consistent with the structure of PA (36:2). c, Analogous lipidomics analysis of purified β1AR from insect cells with three technical replicates. MS/MS spectra of the two [M-H-1] precursor ions (m/z 758.50 and 786.53) identified the lipids as PS (34:2) and PS (36:2) respectively with diagnostic fragments indicated.
