Fig. 1: Cryo-EM structures of the RXFP3−Gi and RXFP4 −Gi complexes.
From: Molecular mechanism underlying non-discriminatory recognition of relaxin-3 by RXFP3 and RXFP4
a Activity of INSL5 at RXFP4 and cross-reactivity of compound 4 and relaxin-3 at RXFP3 and RXFP4, with line thickness indicating efficiency. b Sequence and conformational comparison of relaxin-3 and INSL5. c, d cAMP signaling induced by different ligands in cells expressing wild-type RXFP3 and RXFP4. Data shown are means ± S.E.M. of three independent experiments (n = 3) performed in quadruplicate. e–j Cryo-EM density maps (e–g) and cartoon representation (h–j) of the relaxin-3−RXFP3−Gi complex (e, h), relaxin-3−RXFP4−Gi complex (f, i), and compound 4−RXFP3−Gi complex (h, j). Atomic models and EM densities of the three ligands are shown as sticks and surfaces, respectively. Compound 4 is shown in peru, the A chain of relaxin-3 is shown in light steel blue or light coral, and the B chain is in medium purple or violet in relaxin-3-bound RXFP3 or RXFP4, respectively. Compound 4 and relaxin-3-bound RXFP3 are shown in pale violet red and rosy brown, respectively, while relaxin-3-bound RXFP4 is shown in pale blue. Gαi in cornflower blue, Gβ in dark salmon, Gγ in plum, and scFv16 in dark gray.
