Mouse receptor-activity-modifying proteins 1, -2 and -3: amino acid sequence, expression and function
Introduction
Human (h) receptor-activity-modifying-proteins (RAMPs) 1 and -2 with single transmembrane domains are required for function of h- and rat (r) calcitonin (CT) receptor-like receptors (CRLRs) as a calcitonin gene-related peptide (CGRP) or an adrenomedullin (ADM) receptor, respectively (McLatchie et al., 1998, Muff et al., 1998, Bühlmann et al., 1999). Human RAMP1 and -2 are thought to be co-transported with hCRLR to the cell surface (McLatchie et al., 1998, Fraser et al., 1999).
The 52 and 50 amino acid h- and rADM, and the 37 amino acid h- and rα- and rβCGRP are potent vasodilators. They share limited structural homology with the hypocalcemic thyroid C-cell-derived hormone CT, and with amylin which is co-secreted with insulin from pancreatic β-cells (Wimalawansa, 1997). Common structural elements of the four peptides including six or seven amino acid ring structures, linked by a disulfide bridge, and amidated C-termini, are required for biological activity. The C-terminal fragments hADM (20-52), rADM (20–50) and h- and rαCGRP (8–37), lacking the ring structure, are antagonists of the corresponding intact peptides (Chiba et al., 1989, Eguchi et al., 1994a). Human- and rADM encoding mRNA are expressed in adrenal medulla, lung, kidney and heart, and the peptide has been identified in endothelial and vascular smooth muscle cells (Kitamura et al., 1993, Sakata et al., 1993, Sugo et al., 1994a, Sugo et al., 1994b). Human and rαCGRP are alternatively spliced products of the corresponding CT genes (Amara et al., 1982, Steenbergh et al., 1985a). Human- and rαCGRP differ in 3 and 1 amino acids from h- and rβCGRP, respectively (Amara et al., 1985, Steenbergh et al., 1985b). α- and βCGRP are widely expressed in the central and peripheral nervous system (van Rossum et al., 1997, Wimalawansa, 1997).
An ADM receptor revealed in cultured neuroblastoma cells coupled to cAMP production and antagonized by hADM(22–52) did not recognize CGRP to any great extent (Zimmermann et al., 1996). A different ADM/CGRP receptor also coupled to cAMP production and antagonized by CGRP(8–37) has been demonstrated in human SK-N-MC neuroblastoma and rat vascular smooth muscle cells (Eguchi et al., 1994b, Ishizaka et al., 1994, Zimmermann et al., 1995). ADM receptors can therefore be distinguished from ADM/CGRP receptors.
In the present study RAMP1, -2 and -3 from mouse have been identified and characterized. Co-expression of rCRLR with mRAMP3 in COS-7 cells revealed an ADM/CGRP receptor different from CGRP- or ADM receptors reported earlier (Bühlmann et al., 1999) in the same cells co-transfected with cDNA encoding the rCRLR and hRAMP1 and -2.
Section snippets
Materials
Rat- and hαCGRP and rat amylin were purchased from Bachem (Bubendorf, Switzerland) and rβCGRP, rαCGRP(8-37) and rCT from Peninsula Laboratories (Belmont, CA). Rat ADM was from the Peptide Institute (Osaka, Japan), and rADM(20–50) from Phoenix Pharmaceuticals (Mountain View, CA). Culture media and fetal calf serum (FCS) were obtained from Biological Industries (Kibbutz Beit Haemek, Israel). OptiMEM 1 medium and LipofectAMINE were from Life Technologies (Gaithersburg, MD). Na125I was supplied by
Sequence analysis of mouse RAMP1, -2 and -3 cDNAs
A search of the GenEMBL database with cDNA sequences encoding hRAMP1, -2 and -3 revealed ESTs from different mouse tissues with significant homology to all three hRAMPs. Three cDNA clones of 813, 781 and 1222 bp contained complete open reading frames encoding proteins of 148, 189 and 147 amino acids with 70, 68 and 84% amino acid sequence identity to hRAMP1, -2 and -3, respectively (Fig. 1). In all three RAMPs predicted N-terminal signal sequences and single transmembrane domains were conserved
Discussion
Human RAMP1, -2 and -3 belong to a structurally heterogeneous group of accessory proteins of seven-transmembrane G-protein coupled receptors with different functions (Baker et al., 1994, Ferreira et al., 1996, Dwyer et al., 1998, McLatchie et al., 1998). Human RAMP1 and -2 are presumed to be co-transported with hCRLR to the cell surface, where they reveal different glycosylation of the receptors and define specific CGRP or ADM function of the h- and the rCRLR (McLatchie et al., 1998, Bühlmann
Acknowledgements
The technical assistence of B. Langsam and A. Wyss is gratefully acknowledged. This work was supported by the Swiss National Science Foundation and the Kanton of Zurich.
References (36)
- et al.
A cDNA encoding the calcitonin gene-related peptide type 1 receptor
J. Biol. Chem.
(1996) - et al.
Identification of a seven transmembrane helix receptor for corticotropin-releasing factor and sauvagine in mammalian brain
Neuron
(1993) - et al.
Odorant receptor localization to olfactory cilia is mediated by ODR-4, a novel membrane associated protein
Cell
(1998) - et al.
Specific receptors for adrenomedullin in cultured rat vascular smooth muscle cells
FEBS Lett.
(1994) - et al.
A human orphan calcitonin receptor-like structure
Biochem. Biophys. Res. Commun.
(1995) - et al.
Tissue-specific mRNA expression of a calcitonin receptor-like receptor during fetal and postnatal development
Brain Res.
(1997) - et al.
RAMPs: accessory proteins for seven transmembrane domain receptors
Trends Pharmacol. Sci.
(1999) - et al.
Adrenomedullin stimulates cyclic AMP formation in rat vascular smooth muscle cells
Biochem. Biophys. Res. Commun.
(1994) - et al.
Cloning and characterization of cDNA encoding a precursor for human adrenomedullin
Biochem. Biophys. Res. Commun.
(1993) - et al.
Receptor activity modifying proteins regulate the activity of a calcitonin gene-related peptide receptor in rabbit aortic endothelial cells
FEBS Lett.
(1998)
Rapid and sensitive sequence comparison with FASTP and FASTA
Methods Enzymol.
Molecular cloning and biological activities of rat adrenomedullin, a hypotensive peptide
Biochem. Biophys. Res. Commun.
Endothelial cells activily synthesize and secrete adrenomedullin
Biochem. Biophys. Res. Commun.
Production and secretion of adrenomedullin from vascular smooth muscle cells: augmented production by tumor necrosis factor-alpha
Biochem. Biophys. Res. Commun.
Neuroanatomical localization, pharmacological characterization and functions of CGRP, related peptides and their receptors
Neurosci. Biobehav. Rev.
Identification of adrenomedullin receptors in cultured rat astrocytes and in neuroblastoma x glioma hybrid cells (NG108-15)
Brain Res.
Adrenomedullin and calcitonin gene-related peptide interact with the same receptor in cultured human neuroblastoma SK-N-MC cells
Peptides
Alternative RNA processing in calcitonin gene expression generates mRNAs encoding different polypeptide products
Nature
Cited by (77)
Amylin brain circuitry
2020, PeptidesCitation Excerpt :More specifically, in the brain, using in situ hybridization, RAMP1 is localized in the brainstem, AP, NAc, cortex, hippocampus, caudate putamen, olfactory tubercles, subcomissural organ [20]. RAMP2 mRNA expression is abundant in the hypothalamus [19] and is also expressed but at a lower level in olfactory bulb, hippocampus, choroid plexus of the 3rd, 4th and lateral ventricles and blood vessels throughout the brain [20,21]. RAMP3 is the most abundant in the dorsal thalamus [19], lateral geniculate, and lower amounts are detected in the subfornical organ (SFO) and AP.
Cardiovascular effects of exogenous adrenomedullin and CGRP in Ramp and Calcrl deficient mice
2017, PeptidesCitation Excerpt :This suggests that the AM-induced hypotension is primarily mediated through the CLR/RAMP1 heterodimer, which has historically been considered the CGRP receptor. However, even at an affinity of 1–2 orders of magnitude lower than CGRP, the affinity of AM for CLR/RAMP1 still has physiological effects [35,36]. With the CLR/RAMP1 heterodimer established as a primary mediator of the hypotensive response, it stands to reason that AM causes a hypotensive response similar to CGRP at a dosage of 1–2 orders of magnitude higher, given their relative affinities.
Cyclic AC253, a novel amylin receptor antagonist, improves cognitive deficits in a mouse model of Alzheimer's disease
2017, Alzheimer's and Dementia: Translational Research and Clinical InterventionsModulation of glucagon receptor pharmacology by receptor activity-modifying protein-2 (RAMP2)
2015, Journal of Biological ChemistryCitation Excerpt :Although the GCGR is expressed in the liver, where its main biological function is to counterbalance insulin actions, it is also expressed in a vast array of other tissues (50), including the lung, pancreas, and kidney. Interestingly, in mouse studies, varying levels of RAMP2 mRNA have been reported in these tissues (35). RAMP2 expression was higher in the pancreas, where GCGR stimulation enhances glucagon secretion (50), than in the liver, where receptor activity stimulates glucose release (6).
Cloning of two members of the calcitonin-family receptors from stingray, Dasyatis akajei: Possible physiological roles of the calcitonin family in osmoregulation
2012, GeneCitation Excerpt :We also cloned a part of genomic DNA including the CGRP gene from flounder (Paralichthys olivaceus) and detected mRNA expression in the brain and heart (Suzuki et al., 2001), suggesting that CGRP acts as a neuropeptide and a vasodilator in fish as well as mammals, as CGRP immunoreactivity has been detected in the brain of small-spotted dogfish (Molist et al., 1995), and may be quite important in homeostasis in all fish including cartilaginous fish (Lafont et al., 2007). On the other hand, calcitonin receptor-like receptor (CRLR) functions to a receptor for CGRP when it is co-expressed with RAMP1 (Husmann et al., 2000; McLatchie et al., 1998; Sexton et al., 2001). The distribution and expression analysis of CRLR under various physiological and environmental conditions could contribute to the understanding of physiological functions of CGRP in cartilaginous fish.
Loss of receptor activity-modifying protein 3 exacerbates cardiac hypertrophy and transition to heart failure in a sex-dependent manner
2012, Journal of Molecular and Cellular Cardiology