Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 2001 Feb 1;353(Pt 3):627–634. doi: 10.1042/0264-6021:3530627

5-Hydroxytryptamine 4(a) receptor expressed in Sf9 cells is palmitoylated in an agonist-dependent manner.

E G Ponimaskin 1, M F Schmidt 1, M Heine 1, U Bickmeyer 1, D W Richter 1
PMCID: PMC1221609  PMID: 11171060

Abstract

The mouse 5-hydroxytryptamine 4(a) receptor [5-HT(4(a))] was expressed with a baculovirus system in insect cells and analysed for acylation. [(3)H]Palmitic acid was effectively incorporated into 5-HT(4(a)) and label was sensitive to the treatment with reducing agents indicating a thioester-type bond. Analysis of protein-bound fatty acids revealed that 5-HT(4(a)) contains predominantly palmitic acid. Treatment of infected Sf9 (Spodoptera frugiperda) cells with BIMU8 [(endo-N-8-methyl-8-azabicyclo[3.2.1]oct-3-yl)-2,3-dehydro-2-oxo-3-(prop-2-yl)-1H-benzimid-azole-1-carboxamide], a 5-HT(4) receptor-selective agonist, generated a dose-dependent increase in [(3)H]palmitate incorporation into 5-HT(4(a)) with an EC(50) of approx. 10 nM. The change in receptor labelling after stimulation with agonist was receptor-specific and did not result from general metabolic effects. We also used both pulse labelling and pulse-chase labelling to address the dynamics of 5-HT(4(a)) palmitoylation. Incorporation studies revealed that the rate of palmitate incorporation was increased approx. 3-fold after stimulation with agonist. Results of pulse-chase experiments show that activation with BIMU8 promoted the release of radiolabel from 5-HT(4(a)), thereby reducing the levels of receptor-bound palmitate to approximately one-half. Taken together, our results demonstrate that palmitoylation of 5-HT(4(a)) is a reversible process and that stimulation of 5-HT(4(a)) with agonist increases the turnover rate for receptor-bound palmitate. This provides evidence for a regulated cycling of receptor-bound palmitate and suggests a functional role for palmitoylation/depalmitoylation in 5-hydroxytryptamine-mediated signalling.

Full Text

The Full Text of this article is available as a PDF (248.6 KB).

Selected References

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

  1. Bender E., Pindon A., van Oers I., Zhang Y. B., Gommeren W., Verhasselt P., Jurzak M., Leysen J., Luyten W. Structure of the human serotonin 5-HT4 receptor gene and cloning of a novel 5-HT4 splice variant. J Neurochem. 2000 Feb;74(2):478–489. doi: 10.1046/j.1471-4159.2000.740478.x. [DOI] [PubMed] [Google Scholar]
  2. Bonhomme N., Cador M., Stinus L., Le Moal M., Spampinato U. Short and long-term changes in dopamine and serotonin receptor binding sites in amphetamine-sensitized rats: a quantitative autoradiographic study. Brain Res. 1995 Mar 27;675(1-2):215–223. doi: 10.1016/0006-8993(95)00067-z. [DOI] [PubMed] [Google Scholar]
  3. Boutin J. A. Myristoylation. Cell Signal. 1997 Jan;9(1):15–35. doi: 10.1016/s0898-6568(96)00100-3. [DOI] [PubMed] [Google Scholar]
  4. Bouvier M., Loisel T. P., Hebert T. Dynamic regulation of G-protein coupled receptor palmitoylation: potential role in receptor function. Biochem Soc Trans. 1995 Aug;23(3):577–581. doi: 10.1042/bst0230577. [DOI] [PubMed] [Google Scholar]
  5. Chen C. A., Manning D. R. Regulation of galpha i palmitoylation by activation of the 5-hydroxytryptamine-1A receptor. J Biol Chem. 2000 Aug 4;275(31):23516–23522. doi: 10.1074/jbc.M003439200. [DOI] [PubMed] [Google Scholar]
  6. Claeysen S., Sebben M., Becamel C., Bockaert J., Dumuis A. Novel brain-specific 5-HT4 receptor splice variants show marked constitutive activity: role of the C-terminal intracellular domain. Mol Pharmacol. 1999 May;55(5):910–920. [PubMed] [Google Scholar]
  7. Dunphy J. T., Linder M. E. Signalling functions of protein palmitoylation. Biochim Biophys Acta. 1998 Dec 8;1436(1-2):245–261. doi: 10.1016/s0005-2760(98)00130-1. [DOI] [PubMed] [Google Scholar]
  8. Eason M. G., Jacinto M. T., Theiss C. T., Liggett S. B. The palmitoylated cysteine of the cytoplasmic tail of alpha 2A-adrenergic receptors confers subtype-specific agonist-promoted downregulation. Proc Natl Acad Sci U S A. 1994 Nov 8;91(23):11178–11182. doi: 10.1073/pnas.91.23.11178. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Eglen R. M., Wong E. H., Dumuis A., Bockaert J. Central 5-HT4 receptors. Trends Pharmacol Sci. 1995 Nov;16(11):391–398. doi: 10.1016/s0165-6147(00)89081-1. [DOI] [PubMed] [Google Scholar]
  10. Fagni L., Dumuis A., Sebben M., Bockaert J. The 5-HT4 receptor subtype inhibits K+ current in colliculi neurones via activation of a cyclic AMP-dependent protein kinase. Br J Pharmacol. 1992 Apr;105(4):973–979. doi: 10.1111/j.1476-5381.1992.tb09087.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Gao Z., Ni Y., Szabo G., Linden J. Palmitoylation of the recombinant human A1 adenosine receptor: enhanced proteolysis of palmitoylation-deficient mutant receptors. Biochem J. 1999 Sep 1;342(Pt 2):387–395. [PMC free article] [PubMed] [Google Scholar]
  12. Gordon J. I., Duronio R. J., Rudnick D. A., Adams S. P., Gokel G. W. Protein N-myristoylation. J Biol Chem. 1991 May 15;266(14):8647–8650. [PubMed] [Google Scholar]
  13. Gurdal H., Seasholtz T. M., Wang H. Y., Brown R. D., Johnson M. D., Friedman E. Role of G alpha q or G alpha o proteins in alpha 1-adrenoceptor subtype-mediated responses in Fischer 344 rat aorta. Mol Pharmacol. 1997 Dec;52(6):1064–1070. doi: 10.1124/mol.52.6.1064. [DOI] [PubMed] [Google Scholar]
  14. Kaufman J. F., Krangel M. S., Strominger J. L. Cysteines in the transmembrane region of major histocompatibility complex antigens are fatty acylated via thioester bonds. J Biol Chem. 1984 Jun 10;259(11):7230–7238. [PubMed] [Google Scholar]
  15. Liu J., García-Cardeña G., Sessa W. C. Biosynthesis and palmitoylation of endothelial nitric oxide synthase: mutagenesis of palmitoylation sites, cysteines-15 and/or -26, argues against depalmitoylation-induced translocation of the enzyme. Biochemistry. 1995 Sep 26;34(38):12333–12340. doi: 10.1021/bi00038a029. [DOI] [PubMed] [Google Scholar]
  16. Loisel T. P., Adam L., Hebert T. E., Bouvier M. Agonist stimulation increases the turnover rate of beta 2AR-bound palmitate and promotes receptor depalmitoylation. Biochemistry. 1996 Dec 10;35(49):15923–15932. doi: 10.1021/bi9611321. [DOI] [PubMed] [Google Scholar]
  17. Magee A. I., Gutierrez L., McKay I. A., Marshall C. J., Hall A. Dynamic fatty acylation of p21N-ras. EMBO J. 1987 Nov;6(11):3353–3357. doi: 10.1002/j.1460-2075.1987.tb02656.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Marchetti-Gauthier E., Roman F. S., Dumuis A., Bockaert J., Soumireu-Mourat B. BIMU1 increases associative memory in rats by activating 5-HT4 receptors. Neuropharmacology. 1997 Apr-May;36(4-5):697–706. doi: 10.1016/s0028-3908(97)00058-0. [DOI] [PubMed] [Google Scholar]
  19. McGlade C. J., Tremblay M. L., Yee S. P., Ross R., Branton P. E. Acylation of the 176R (19-kilodalton) early region 1B protein of human adenovirus type 5. J Virol. 1987 Oct;61(10):3227–3234. doi: 10.1128/jvi.61.10.3227-3234.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Moffett S., Mouillac B., Bonin H., Bouvier M. Altered phosphorylation and desensitization patterns of a human beta 2-adrenergic receptor lacking the palmitoylated Cys341. EMBO J. 1993 Jan;12(1):349–356. doi: 10.1002/j.1460-2075.1993.tb05663.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Morales J., Fishburn C. S., Wilson P. T., Bourne H. R. Plasma membrane localization of G alpha z requires two signals. Mol Biol Cell. 1998 Jan;9(1):1–14. doi: 10.1091/mbc.9.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Mumby S. M., Kleuss C., Gilman A. G. Receptor regulation of G-protein palmitoylation. Proc Natl Acad Sci U S A. 1994 Mar 29;91(7):2800–2804. doi: 10.1073/pnas.91.7.2800. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Mumby S. M. Reversible palmitoylation of signaling proteins. Curr Opin Cell Biol. 1997 Apr;9(2):148–154. doi: 10.1016/s0955-0674(97)80056-7. [DOI] [PubMed] [Google Scholar]
  24. Ng G. Y., Mouillac B., George S. R., Caron M., Dennis M., Bouvier M., O'Dowd B. F. Desensitization, phosphorylation and palmitoylation of the human dopamine D1 receptor. Eur J Pharmacol. 1994 Mar 15;267(1):7–19. doi: 10.1016/0922-4106(94)90219-4. [DOI] [PubMed] [Google Scholar]
  25. Okamoto Y., Ninomiya H., Tanioka M., Sakamoto A., Miwa S., Masaki T. Palmitoylation of human endothelinB. Its critical role in G protein coupling and a differential requirement for the cytoplasmic tail by G protein subtypes. J Biol Chem. 1997 Aug 22;272(34):21589–21596. doi: 10.1074/jbc.272.34.21589. [DOI] [PubMed] [Google Scholar]
  26. Ponimaskin E., Harteneck C., Schultz G., Schmidt M. F. A cysteine-11 to serine mutant of G alpha12 impairs activation through the thrombin receptor. FEBS Lett. 1998 Jun 16;429(3):370–374. doi: 10.1016/s0014-5793(98)00638-3. [DOI] [PubMed] [Google Scholar]
  27. Ponimaskin E., Schmidt M. F. Acylation of viral glycoproteins: structural requirements for palmitoylation of transmembrane proteins. Biochem Soc Trans. 1995 Aug;23(3):565–568. doi: 10.1042/bst0230565. [DOI] [PubMed] [Google Scholar]
  28. Ponimaskin E., Schmidt M. F. Domain-structure of cytoplasmic border region is main determinant for palmitoylation of influenza virus hemagglutinin (H7). Virology. 1998 Sep 30;249(2):325–335. doi: 10.1006/viro.1998.9303. [DOI] [PubMed] [Google Scholar]
  29. Probst W. C., Snyder L. A., Schuster D. I., Brosius J., Sealfon S. C. Sequence alignment of the G-protein coupled receptor superfamily. DNA Cell Biol. 1992 Jan-Feb;11(1):1–20. doi: 10.1089/dna.1992.11.1. [DOI] [PubMed] [Google Scholar]
  30. Resh M. D. Fatty acylation of proteins: new insights into membrane targeting of myristoylated and palmitoylated proteins. Biochim Biophys Acta. 1999 Aug 12;1451(1):1–16. doi: 10.1016/s0167-4889(99)00075-0. [DOI] [PubMed] [Google Scholar]
  31. Ross E. M. Protein modification. Palmitoylation in G-protein signaling pathways. Curr Biol. 1995 Feb 1;5(2):107–109. doi: 10.1016/s0960-9822(95)00026-1. [DOI] [PubMed] [Google Scholar]
  32. Sachs K., Maretzki D., Meyer C. K., Hofmann K. P. Diffusible ligand all-trans-retinal activates opsin via a palmitoylation-dependent mechanism. J Biol Chem. 2000 Mar 3;275(9):6189–6194. doi: 10.1074/jbc.275.9.6189. [DOI] [PubMed] [Google Scholar]
  33. Schmidt M. F. Fatty acylation of proteins. Biochim Biophys Acta. 1989 Dec 6;988(3):411–426. doi: 10.1016/0304-4157(89)90013-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Towler D. A., Gordon J. I., Adams S. P., Glaser L. The biology and enzymology of eukaryotic protein acylation. Annu Rev Biochem. 1988;57:69–99. doi: 10.1146/annurev.bi.57.070188.000441. [DOI] [PubMed] [Google Scholar]
  35. Veit M., Nürnberg B., Spicher K., Harteneck C., Ponimaskin E., Schultz G., Schmidt M. F. The alpha-subunits of G-proteins G12 and G13 are palmitoylated, but not amidically myristoylated. FEBS Lett. 1994 Feb 14;339(1-2):160–164. doi: 10.1016/0014-5793(94)80406-0. [DOI] [PubMed] [Google Scholar]
  36. Wedegaertner P. B., Bourne H. R. Activation and depalmitoylation of Gs alpha. Cell. 1994 Jul 1;77(7):1063–1070. doi: 10.1016/0092-8674(94)90445-6. [DOI] [PubMed] [Google Scholar]
  37. Wong E. H., Reynolds G. P., Bonhaus D. W., Hsu S., Eglen R. M. Characterization of [3H]GR 113808 binding to 5-HT4 receptors in brain tissues from patients with neurodegenerative disorders. Behav Brain Res. 1996;73(1-2):249–252. doi: 10.1016/0166-4328(96)00106-4. [DOI] [PubMed] [Google Scholar]

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

RESOURCES