Respective roles of calcitonin receptor-like receptor (CRLR) and receptor activity-modifying proteins (RAMP) in cell surface expression of CRLR/RAMP heterodimeric receptors.
Data(s) |
2002
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Resumo |
Receptor activity modifying proteins RAMP1, RAMP2, and RAMP3 are responsible for defining affinity to ligands of the calcitonin receptor-like receptor (CRLR). It has also been proposed that receptor activity-modifying proteins (RAMP) are molecular chaperones required for CRLR transport to the cell surface. Here, we have studied the respective roles of CRLR and RAMP in transporting CRLR/RAMP heterodimers to the plasma membrane by using a highly specific binding assay that allows quantitative detection of cell surface-expressed CRLR or RAMP in the Xenopus oocytes expression system. We show that: (i) heterodimer assembly is not a prerequisite for efficient cell surface expression of CRLR, (ii) N-glycosylated RAMP2 and RAMP3 are expressed at the cell surface and their transport to the plasma membrane requires N-glycans, (iii) RAMP1 is not N-glycosylated and is transported to the plasma membrane only upon formation of heterodimers with CRLR, and (iv) introduction of N-glycosylation sites in the RAMP1 sequence (D58N/G60S, Y71N, and K103N/P105S) allows cell surface expression of these mutants at levels similar to that of wild-type RAMP1 co-expressed with CRLR. Our data argue against a chaperone function for RAMP and identify the role of N-glycosylation in targeting these molecules to the cell surface. |
Identificador |
http://serval.unil.ch/?id=serval:BIB_81C4D4DE57EB isbn:0021-9258 (Print) pmid:11854283 doi:10.1074/jbc.M112084200 isiid:000175203000050 |
Idioma(s) |
en |
Fonte |
Journal of Biological Chemistry, vol. 277, no. 17, pp. 14731-14737 |
Palavras-Chave | #Animals; Calcitonin Receptor-Like Protein; Cell Membrane/metabolism; DNA, Complementary; Dimerization; Glycosylation; Intracellular Signaling Peptides and Proteins; Membrane Proteins/genetics; Membrane Proteins/physiology; Mice; Mutagenesis, Site-Directed; Receptor Activity-Modifying Protein 1; Receptor Activity-Modifying Protein 2; Receptor Activity-Modifying Protein 3; Receptor Activity-Modifying Proteins; Receptors, Calcitonin/physiology; Xenopus |
Tipo |
info:eu-repo/semantics/article article |