Figure 3.

Activity of Cy5.5 insulin/relaxin family peptide analogs at RXFP1 or RXFP2. (A) Competition binding of native relaxin and Cy5.5-H2 relaxin analogs in the presence of the competitive ligand Eu³⁺-labeled H2 relaxin tested in HEK-293T cells stably expressing RXFP1. (B) Effect of native H2 relaxin and Cy5.5-H2 relaxin analogs on cAMP-related activity in HEK-293T cells expressing RXFP1 using a pCRE-galactosidase reporter gene system. (C) Competition binding of native INSL3 and Cy5.5-INSL3 in the presence of the competitive ligand Eu³⁺-labeled INSL3 tested in HEK-293T cells stably expressing RXFP2. (D) Effect of native INSL3 and Cy5.5-INSL3 on cAMP activity in HEK-293T cells expressing RXFP2 using a pCRE-galactosidase reporter gene system. Data are expressed as a percentage of specific binding or maximum relaxin/INSL3-stimulated cAMP response and are pooled data from at least three experiments performed in triplicate.