Multiplexed analysis of the secretin-like GPCR-RAMP interactome

Sci Adv. 2019 Sep 18;5(9):eaaw2778. doi: 10.1126/sciadv.aaw2778. eCollection 2019 Sep.


Receptor activity-modifying proteins (RAMPs) have been shown to modulate the functions of several G protein-coupled receptors (GPCRs), but potential direct interactions among the three known RAMPs and hundreds of GPCRs have never been investigated. Focusing mainly on the secretin-like family of GPCRs, we engineered epitope-tagged GPCRs and RAMPs, and developed a multiplexed suspension bead array (SBA) immunoassay to detect GPCR-RAMP complexes from detergent-solubilized lysates. Using 64 antibodies raised against the native proteins and 4 antibodies targeting the epitope tags, we mapped the interactions among 23 GPCRs and 3 RAMPs. We validated nearly all previously reported secretin-like GPCR-RAMP interactions, and also found previously unidentified RAMP interactions with additional secretin-like GPCRs, chemokine receptors, and orphan receptors. The results provide a complete interactome of secretin-like GPCRs with RAMPs. The SBA strategy will be useful to search for additional GPCR-RAMP complexes and other interacting membrane protein pairs in cell lines and tissues.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • HEK293 Cells
  • Humans
  • Protein Interaction Mapping*
  • Receptor Activity-Modifying Proteins / genetics
  • Receptor Activity-Modifying Proteins / metabolism*
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism*
  • Secretin / genetics
  • Secretin / metabolism*


  • Receptor Activity-Modifying Proteins
  • Receptors, G-Protein-Coupled
  • Secretin