FIGURE 5.

Model of the RXFP3-H3 relaxin complex. H3 relaxin is shown in pink and RXFP3 in gray. All Asp/Glu residues in RXFP3 mutated during this study are shown in red and labeled with residue numbers. Key Arg and hydrophobic residues in H3 relaxin involved in the receptor binding are highlighted in blue and green, respectively, and labeled with residue numbers. Key features are the electrostatic interactions between the positively charged R12, R16, and R26 of H3 relaxin and the negatively charged E244, D145, and E141 of RXFP3, respectively.