Biologjia Online

Three receptor activity-modifying proteins (RAMPs 1, 2, and 3) are required for plasma membrane expression and ligand binding of several G-protein-coupled receptors. For example, if RAMP1 binds to the calcitonin receptor-like receptor (CRLR), then a cell surface calcitonin generelated peptide 1 receptor is produced. In contrast, the binding of RAMP2 or -3 to CRLR produces an adrenomedullin peptide receptor. Jennifer M. Bomberger and colleagues now show that in addition to these roles, RAMP3 binding to the CRLR is required for recycling of internalized adrenomedullin receptors.