Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 2000 Sep 15;350(Pt 3):839–847.

Requirement of N-glycosylation of the prostaglandin E2 receptor EP3beta for correct sorting to the plasma membrane but not for correct folding.

U Böer 1, F Neuschäfer-Rube 1, U Möller 1, G P Püschel 1
PMCID: PMC1221318  PMID: 10970800

Abstract

Eight heptahelical receptors have been characterized for prostaglandin (PG) D(2), PGE(2), PGF(2alpha), prostacyclin and thromboxane A(2). They share a sequence identity of 40%. All of them have potential N-glycosylation sites. The current study analysed the role of the two N-glycosylation sites in the rat EP3beta-subtype PGE(2) receptor for protein folding and sorting. The N-glycosylation consensus sequences were eliminated by site-directed mutagenesis and receptors expressed in HEK-293 cells. Both potential N-glycosylation sites were used. Their joint elimination resulted in the synthesis of a receptor protein with full binding competence, biological activity and no reduction of affinity; however, the half-life of the non-glycosylated receptor was slightly reduced. Ligand binding to intact stably transfected cells and confocal laser microscopic immunocytochemistry showed that the glycosylated receptor was correctly inserted into the plasma membrane to a much larger extent than the non-glycosylated receptor, which tended to accumulate in the perinuclear zone of the endoplasmic reticulum. Inhibition of N-glycosylation with tunicamycin resulted in a similar perinuclear distribution of the wild-type receptor. Therefore, glycosylation of the EP3beta receptor seems not to be necessary for correct folding of the receptor protein but for the efficient transport of the receptor protein to the plasma membrane. This contrasts with a previous finding which described a reduction of the affinity for PGE(2) of the EP3alpha receptor by elimination of the distal glycosylation site when the receptor protein was expressed in insect cells.

Full Text

The Full Text of this article is available as a PDF (361.1 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Altmann F., Staudacher E., Wilson I. B., März L. Insect cells as hosts for the expression of recombinant glycoproteins. Glycoconj J. 1999 Feb;16(2):109–123. doi: 10.1023/a:1026488408951. [DOI] [PubMed] [Google Scholar]
  2. Audoly L., Breyer R. M. Substitution of charged amino acid residues in transmembrane regions 6 and 7 affect ligand binding and signal transduction of the prostaglandin EP3 receptor. Mol Pharmacol. 1997 Jan;51(1):61–68. doi: 10.1124/mol.51.1.61. [DOI] [PubMed] [Google Scholar]
  3. Audoly L., Breyer R. M. The second extracellular loop of the prostaglandin EP3 receptor is an essential determinant of ligand selectivity. J Biol Chem. 1997 May 23;272(21):13475–13478. doi: 10.1074/jbc.272.21.13475. [DOI] [PubMed] [Google Scholar]
  4. Benting J. H., Rietveld A. G., Simons K. N-Glycans mediate the apical sorting of a GPI-anchored, raft-associated protein in Madin-Darby canine kidney cells. J Cell Biol. 1999 Jul 26;146(2):313–320. doi: 10.1083/jcb.146.2.313. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Coleman R. A., Smith W. L., Narumiya S. International Union of Pharmacology classification of prostanoid receptors: properties, distribution, and structure of the receptors and their subtypes. Pharmacol Rev. 1994 Jun;46(2):205–229. [PubMed] [Google Scholar]
  6. Fukushima Y., Oka Y., Saitoh T., Katagiri H., Asano T., Matsuhashi N., Takata K., van Breda E., Yazaki Y., Sugano K. Structural and functional analysis of the canine histamine H2 receptor by site-directed mutagenesis: N-glycosylation is not vital for its action. Biochem J. 1995 Sep 1;310(Pt 2):553–558. doi: 10.1042/bj3100553. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gut A., Kappeler F., Hyka N., Balda M. S., Hauri H. P., Matter K. Carbohydrate-mediated Golgi to cell surface transport and apical targeting of membrane proteins. EMBO J. 1998 Apr 1;17(7):1919–1929. doi: 10.1093/emboj/17.7.1919. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Hammond C., Helenius A. Quality control in the secretory pathway. Curr Opin Cell Biol. 1995 Aug;7(4):523–529. doi: 10.1016/0955-0674(95)80009-3. [DOI] [PubMed] [Google Scholar]
  9. Helenius A. How N-linked oligosaccharides affect glycoprotein folding in the endoplasmic reticulum. Mol Biol Cell. 1994 Mar;5(3):253–265. doi: 10.1091/mbc.5.3.253. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Hooker A. D., Green N. H., Baines A. J., Bull A. T., Jenkins N., Strange P. G., James D. C. Constraints on the transport and glycosylation of recombinant IFN-gamma in Chinese hamster ovary and insect cells. Biotechnol Bioeng. 1999 Jun 5;63(5):559–572. doi: 10.1002/(sici)1097-0290(19990605)63:5<559::aid-bit6>3.0.co;2-l. [DOI] [PubMed] [Google Scholar]
  11. Huang C., Tai H. H. Prostaglandin E2 receptor EP3alpha subtype: the role of N-glycosylation in ligand binding as revealed by site-directed mutagenesis. Prostaglandins Leukot Essent Fatty Acids. 1998 Oct;59(4):265–271. doi: 10.1016/s0952-3278(98)90140-5. [DOI] [PubMed] [Google Scholar]
  12. Innamorati G., Sadeghi H., Birnbaumer M. A fully active nonglycosylated V2 vasopressin receptor. Mol Pharmacol. 1996 Sep;50(3):467–473. [PubMed] [Google Scholar]
  13. Jarvis D. L., Finn E. E. Biochemical analysis of the N-glycosylation pathway in baculovirus-infected lepidopteran insect cells. Virology. 1995 Oct 1;212(2):500–511. doi: 10.1006/viro.1995.1508. [DOI] [PubMed] [Google Scholar]
  14. Karpa K. D., Lidow M. S., Pickering M. T., Levenson R., Bergson C. N-linked glycosylation is required for plasma membrane localization of D5, but not D1, dopamine receptors in transfected mammalian cells. Mol Pharmacol. 1999 Nov;56(5):1071–1078. doi: 10.1124/mol.56.5.1071. [DOI] [PubMed] [Google Scholar]
  15. Kaushal S., Ridge K. D., Khorana H. G. Structure and function in rhodopsin: the role of asparagine-linked glycosylation. Proc Natl Acad Sci U S A. 1994 Apr 26;91(9):4024–4028. doi: 10.1073/pnas.91.9.4024. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Kornfeld R., Kornfeld S. Assembly of asparagine-linked oligosaccharides. Annu Rev Biochem. 1985;54:631–664. doi: 10.1146/annurev.bi.54.070185.003215. [DOI] [PubMed] [Google Scholar]
  17. Kornfeld S. Trafficking of lysosomal enzymes. FASEB J. 1987 Dec;1(6):462–468. doi: 10.1096/fasebj.1.6.3315809. [DOI] [PubMed] [Google Scholar]
  18. Lanctôt P. M., Leclerc P. C., Escher E., Leduc R., Guillemette G. Role of N-glycosylation in the expression and functional properties of human AT1 receptor. Biochemistry. 1999 Jul 6;38(27):8621–8627. doi: 10.1021/bi9830516. [DOI] [PubMed] [Google Scholar]
  19. Munson P. J., Rodbard D. Ligand: a versatile computerized approach for characterization of ligand-binding systems. Anal Biochem. 1980 Sep 1;107(1):220–239. doi: 10.1016/0003-2697(80)90515-1. [DOI] [PubMed] [Google Scholar]
  20. Narumiya S. Prostanoid receptors. Structure, function, and distribution. Ann N Y Acad Sci. 1994 Nov 15;744:126–138. doi: 10.1111/j.1749-6632.1994.tb52729.x. [DOI] [PubMed] [Google Scholar]
  21. Neuschäfer-Rube F., DeVries C., Hänecke K., Jungermann K., Püschel G. P. Molecular cloning and expression of a prostaglandin E2 receptor of the EP3 beta subtype from rat hepatocytes. FEBS Lett. 1994 Aug 29;351(1):119–122. doi: 10.1016/0014-5793(94)00837-x. [DOI] [PubMed] [Google Scholar]
  22. Neuschäfer-Rube F., Hänecke K., Blaschke V., Jungermann K., Püschel G. P. The C-terminal domain of the Gs-coupled EP4 receptor confers agonist-dependent coupling control to Gi but no coupling to Gs in a receptor hybrid with the Gi-coupled EP3 receptor. FEBS Lett. 1997 Jan 20;401(2-3):185–190. doi: 10.1016/s0014-5793(96)01468-8. [DOI] [PubMed] [Google Scholar]
  23. Rands E., Candelore M. R., Cheung A. H., Hill W. S., Strader C. D., Dixon R. A. Mutational analysis of beta-adrenergic receptor glycosylation. J Biol Chem. 1990 Jun 25;265(18):10759–10764. [PubMed] [Google Scholar]
  24. Rens-Domiano S., Reisine T. Structural analysis and functional role of the carbohydrate component of somatostatin receptors. J Biol Chem. 1991 Oct 25;266(30):20094–20102. [PubMed] [Google Scholar]
  25. Rudd P. M., Dwek R. A. Glycosylation: heterogeneity and the 3D structure of proteins. Crit Rev Biochem Mol Biol. 1997;32(1):1–100. doi: 10.3109/10409239709085144. [DOI] [PubMed] [Google Scholar]
  26. Scheiffele P., Peränen J., Simons K. N-glycans as apical sorting signals in epithelial cells. Nature. 1995 Nov 2;378(6552):96–98. doi: 10.1038/378096a0. [DOI] [PubMed] [Google Scholar]
  27. Tai H. H., Huang C., Chiang N. Structure and function of prostanoid receptors as revealed by site-directed mutagenesis. Adv Exp Med Biol. 1997;407:205–209. doi: 10.1007/978-1-4899-1813-0_31. [DOI] [PubMed] [Google Scholar]
  28. Thierauch K. H., Dinter H., Stock G. Prostaglandins and their receptors: II. Receptor structure and signal transduction. J Hypertens. 1994 Jan;12(1):1–5. [PubMed] [Google Scholar]
  29. Unson C. G., Cypess A. M., Kim H. N., Goldsmith P. K., Carruthers C. J., Merrifield R. B., Sakmar T. P. Characterization of deletion and truncation mutants of the rat glucagon receptor. Seven transmembrane segments are necessary for receptor transport to the plasma membrane and glucagon binding. J Biol Chem. 1995 Nov 17;270(46):27720–27727. doi: 10.1074/jbc.270.46.27720. [DOI] [PubMed] [Google Scholar]
  30. Weinshank R. L., Zgombick J. M., Macchi M., Adham N., Lichtblau H., Branchek T. A., Hartig P. R. Cloning, expression, and pharmacological characterization of a human alpha 2B-adrenergic receptor. Mol Pharmacol. 1990 Nov;38(5):681–688. [PubMed] [Google Scholar]
  31. Yatsunami K., Fujisawa J., Hashimoto H., Kimura K., Takahashi S., Ichikawa A. Effect of tunicamycin on functions of PGE1 receptors from mouse mastocytoma P-815 cells. Biochim Biophys Acta. 1990 Jan 23;1051(1):94–99. doi: 10.1016/0167-4889(90)90178-g. [DOI] [PubMed] [Google Scholar]
  32. Zheng X., Lu D., Sadler J. E. Apical sorting of bovine enteropeptidase does not involve detergent-resistant association with sphingolipid-cholesterol rafts. J Biol Chem. 1999 Jan 15;274(3):1596–1605. doi: 10.1074/jbc.274.3.1596. [DOI] [PubMed] [Google Scholar]
  33. van Koppen C. J., Nathanson N. M. Site-directed mutagenesis of the m2 muscarinic acetylcholine receptor. Analysis of the role of N-glycosylation in receptor expression and function. J Biol Chem. 1990 Dec 5;265(34):20887–20892. [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES