title: Specificity of porcine calcitonin receptor and calcitonin receptor-like receptor in the presence of receptor-activity-modifying proteins.
abstract: Adrenomedullin (AM), calcitonin gene-related peptide (CGRP), amylin (AMY) and calcitonin (CT) are members of the CGRP/CT superfamily of peptides. Among them, AM and CGRP are reported to share a core receptor, the calcitonin receptor-like receptor (CRLR), and the specificity of the CRLR is determined by the expression levels of receptor-activity-modifying proteins (RAMPs). In the case of AMY, co-expression of the calcitonin receptor (CTR) and RAMPs was recently reported to form its specific receptor. However, detailed analysis of the receptor specificity of the CRLR and CTR in the presence of RAMPs has so far been performed mainly in the human system. Thus, we cloned cDNAs encoding porcine CRLR, RAMP1, RAMP2 and RAMP3 precursors from a porcine lung and hypothalamus cDNA library, and determined their sequences. Then, porcine RAMPs, CRLR and CTR were expressed in COS-7 or porcine vascular smooth muscle cells, and the resulting receptor complexes were analyzed by the cyclic adenosine 3,5-monophosphate (cAMP) production assay. The specificity of CRLR was clearly determined by the expression of RAMPs; RAMP1 converted CRLR to CGRP receptor, while RAMP2 and RAMP3 converted it to AM receptor, but the affinity of CTR for AMY was not increased by the expression of any known RAMPs. In contrast to previous findings, porcine CTR and RAMP did not appear to form an AMY receptor having sufficient affinity and specificity for the physiological interaction.
authors.affiliation: National Cardiovascular Center Research Institute, Suita, Japan.
authors.forename: Katsuro
authors.initials: K
authors.lastname: Kikumoto
authors.forename: Takeshi
authors.initials: T
authors.lastname: Katafuchi
authors.forename: Naoto
authors.initials: N
authors.lastname: Minamino
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism; D053607:Adrenomedullin; D000595:Amino Acid Sequence; D000682:Amyloid / Q000494:pharmacology; D000818:Animals; D019556:COS Cells; D002116:Calcitonin / Q000494:pharmacology; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology; D058286:Calcitonin Receptor-Like Protein; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000378:metabolism; D018076:DNA, Complementary; D004789:Enzyme Activation / Q000187:drug effects; D047908:Intracellular Signaling Peptides and Proteins; D058228:Islet Amyloid Polypeptide; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010455:Peptides / Q000494:pharmacology; D051381:Rats; D058262:Receptor Activity-Modifying Protein 1; D058263:Receptor Activity-Modifying Protein 2; D058264:Receptor Activity-Modifying Protein 3; D058261:Receptor Activity-Modifying Proteins; D018003:Receptors, Calcitonin / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013552:Swine; D014162:Transfection; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D000682:Amyloid; C545578:CALCRL protein, human; D058286:Calcitonin Receptor-Like Protein; D018076:DNA, Complementary; D047908:Intracellular Signaling Peptides and Proteins; D058228:Islet Amyloid Polypeptide; D008565:Membrane Proteins; D010455:Peptides; C545502:RAMP1 protein, human; C545503:RAMP2 protein, human; C545504:RAMP3 protein, human; D058262:Receptor Activity-Modifying Protein 1; D058263:Receptor Activity-Modifying Protein 2; D058264:Receptor Activity-Modifying Protein 3; D058261:Receptor Activity-Modifying Proteins; D018003:Receptors, Calcitonin; D014665:Vasodilator Agents; D053607:Adrenomedullin; D002116:Calcitonin; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D015740:Calcitonin Gene-Related Peptide