We thank Drs. M. Baez, M. Cohen, and D. Nelson (Lilly Research Laboratories) for gifts of AV12 cells and LY53857. We also thank Dr. Anton Mestek for constructing the pcDNA3 vector containing the HA epitope tag. This work was supported in part by NIH grants NS28190, DA09116, DA09444, and DA11891 to L. Y. J.H.H. and L.J.B. were supported by an NIH training grant (HD07373). J.L. was supported by a John B. Hickam Memorial postdoctoral fellowship from the American Heart Association, Indiana Affiliate, Inc. L.Y. was the recipient of an NIH Research Career Development Award (NS01557).

  • 1
    Abramowski D. & Staufenbiel M. (1995) Identification of the 5-hydroxytryptamine2C receptor as a 60-kDa N-glycosylated protein in choroid plexus and hippocampus. J. Neurochem. 65,782790.
  • 2
    Backstrom J.R. & Sanders-Bush E. (1997) Involvement of a tyrosine kinase pathway in agonist-mediated phosphorylation of 5-HT2C receptors.Soc. Neurosci. Abstr. 23,133.
  • 3
    Barker E.L., Westphal R.S., Schmidt D., Sanders-Bush E. (1994) Constitutively active 5-hydroxytryptamine2c receptors reveal novel inverse agonist activity of receptor ligands.J. Biol. Chem. 269,1168711690.
  • 4
    Burns C.M., Chu H., Rueter S.M., Hutchinson L.K., Canton H., Sanders-Bush E., Emeson R.B. (1997) Regulation of serotonin-2C receptor G-protein coupling by RNA editing.Nature 387,303308.
  • 5
    Canton H., Emeson R.B., Barker E.L., Backstrom J.R., Lu J.T., Chang M.S., Sanders-Bush E. (1996) Identification, molecular cloning, and distribution of a short variant of the 5-hydroxytryptamine2C receptor produced by alternative splicing.Mol. Pharmacol. 50,799807.
  • 6
    Chen C. & Okayama H. (1987) High-efficiency transformation of mammalian cells by plasmid DNA.Mol. Cell. Biol. 7,27452752.
  • 7
    Chen Y., Holcomb C., Moore H. -P. (1993) Expression and localization of two low molecular weight GTP-binding proteins, Rab8, and Rab10, by epitope-tag.Proc. Natl. Acad. Sci. USA 90,65086512.
  • 8
    Cheng Y. & Prusoff W.H. (1973) Relationship between the inhibition constant (KI) and the concentration of inhibitor which causes 50 percent inhibition (I50) of an enzymatic reaction. Biochem. Pharmacol. 22,30993108.
  • 9
    Conn P.J., Sanders-Bush E., Hoffman B.J., Hartig P.R. (1986) A unique serotonin receptor in choroid plexus is linked to phosphatidylinositol turnover.Proc. Natl. Acad. Sci. USA 83,40864088.
  • 10
    Dascal N., Ifune C., Hopkins R., Snutch T.P., Lübbert H., Davidson N., Simon M.I., Lester H.A. (1987) Involvement of a GTP-binding protein in mediation of serotonin and acetylcholine responses in Xenopus oocytes injected with rat brain messenger RNA.Mol. Brain Res. 1,201209.
  • 11
    Dixon R.A.F., Sigal I.S., Rands E., Register R.B., Candelore M.R., Blade A.D., Strader C.D. (1987a) Ligand binding to the β-adrenergic receptor involves its rhodopsin-like core. Nature 326,7377.
  • 12
    Dixon R.A.F., Sigal I.S., Candelore M.R., Register R.B., Scattergood W., Rands E., Strader C.D. (1987b) Structural features required for ligand binding to the β-adrenergic receptor. EMBO J. 6,32693275.
  • 13
    Dohlman H.G., Bouvier M., Benovic J.L., Caron M.G., Lefkowitz R.J. (1987) The multiple membrane spanning topography of the β2-adrenergic receptor. J. Biol. Chem. 262,1428214288.
  • 14
    Eisenberg D., Schwarz E., Komaromy M., Wall R. (1984) Analysis of membrane and surface protein sequences with the hydrophobic moment plot.J. Mol. Biol. 179,125142.
  • 15
    Engelman D.M., Henderson R., McLachlan A.D., Wallace B.A. (1980) Path of the polypeptide in bacteriorhodopsin.Proc. Natl. Acad. Sci. USA 77,20232027.
  • 16
    Fargin A., Raymond J.R., Lohse M.J., Kobilka B.K., Caron M.G., Lefkowitz R.J. (1988) The genomic clone G-21 which resembles a beta-adrenergic receptor sequence encodes the 5-HT1A receptor.Nature 335,358360.
  • 17
    Frielle T., Daniel K.W., Caron M.G., Lefkowitz R.J. (1988) Structural basis of β-adrenergic receptor subtype specificity studied with chimeric β12-adrenergic receptors. Proc. Natl. Acad. Sci. USA 85,94949498.
  • 18
    Gerhardt C.C. & Van Heerikhuizen H. (1997) Functional characteristics of heterologously expressed 5-HT receptors.Eur. J. Pharmacol. 334,123.
  • 19
    Gundersen C.B., Miledi R., Parker F.R.S., Parker I. (1983) Serotonin receptors induced by exogenous messenger RNA in Xenopus oocytes.Proc. R. Soc. Lond. 219,103109.
  • 20
    Hoyer D. (1988) Functional correlates of serotonin 5-HT1 recognition sites.J. Receptor Res. 8,5981.
  • 21
    Hoyer D., Engel G., Kalkman H.O. (1985) Molecular pharmacology of 5-HT1 and 5-HT2 recognition sites in rat and pig brain membranes : radioligand binding studies with [3H]5HT, [3H]8-OH-DPAT, (—)[125I]iodocyanopindolol, [3H]mesulergine and [3H]ketanserin. Eur. J. Pharmacol. 118,1323.
  • 22
    Hurley J.H. (1995) Structure-function studies of the serotonin 2C receptor.Ph.D. dissertation, Indiana University School of Medicine.
  • 23
    Julius D., MacDermott A.B., Axel R., Jessell T.M. (1988) Molecular characterization of a functional cDNA encoding the serotonin 1c receptor.Science 241,558564.
  • 24
    Kaufman M.J., Hartig P.R., Hoffman B.J. (1995) Serotonin 5-HT2C receptor stimulates cyclic GMP formation in choroid plexus.J. Neurochem. 64,199205.
  • 25
    Kobilka B.K., Dixon R.A.F., Frielle T., Dohlman H.G., Bolanowski M.A., Sigal I.S., Yang-Feng T.L., Francke U., Caron M.G., Lefkowitz R.J. (1987) cDNA for the human β2-adrenergic receptor : a protein with multiple membrane-spanning domains and encoded by a gene whose chromosomal location is shared with that of the receptor for platelet-derived growth factor. Proc. Natl. Acad. Sci. USA 84,4650.
  • 26
    Kyte J. & Doolittle R.F. (1982) A simple method for displaying the hydropathic character of a protein.J. Mol. Biol. 157,105132.
  • 27
    Labrecque J., Fargin A., Bouvier M., Chidiac P., Dennis M. (1995) Serotonergic antagonists differentially inhibit spontaneous activity and decrease ligand binding capacity of the rat 5-hydroxytryptamine type 2C receptor in Sf9 cells.Mol. Pharmacol. 48,150159.
  • 28
    Lefkowitz R.J. & Caron M.G. (1988) Adrenergic receptors : models for the study of receptors coupled to guanine nucleotide regulatory proteins.J. Biol. Chem. 263,49934996.
  • 29
    Lübbert H., Hoffman B.J., Snutch T.P., Van Dyke T., Levine A.J., Hartig P.R., Lester H.A., Davidson N. (1987) cDNA cloning of a serotonin 5-HT1C receptor by electrophysiological assays of mRNA-injected Xenopus oocytes.Proc. Natl. Acad. Sci. USA 84,43324336.
  • 30
    Meyerhof W., Obermuller F., Fehr S., Richter D. (1993) A novel rat serotonin receptor : primary structure, pharmacology, and expression pattern in distinct brain regions.DNA Cell Biol. 12,401409.
  • 31
    O'Dowd B.F., Lefkowitz R.J., Caron M.G. (1989) Structure of the adrenergic and related receptors.Annu. Rev. Neurosci. 12,6783.
  • 32
    Olsen D.B. & Eckstein F. (1990) High-efficiency oligonucleotide-directed plasmid mutagenesis.Proc. Natl. Acad. Sci. USA 87,14511455.
  • 33
    Ovchinnikov Y.A., Adbulaev N., Feigira M., Kiselev A., Lobanov N. (1979) The structural basis of the functioning of bacteriorhodopsin : an overview.FEBS Lett. 100,219224.
  • 34
    Pavalko F.M. & LaRoche S.M. (1993) Activation of human neutrophils induces an interaction between the integrin beta-2 subunit (CD18) and the actin binding protein alpha-actinin antisera#1642. J. Immunol. 151,37953807.
  • 35
    Pazos A., Hoyer D., Palacios J.M. (1984) The binding of serotonergic ligands to the porcine choroid plexus : characterization of a new type of serotonin recognition site.Eur. J. Pharmacol. 106,539546.
  • 36
    Pebay-Peyroula E., Rummel G., Rosenbusch J.P., Landau E.M. (1997) X-ray structure of bacteriorhodopsin at 2.5 angstroms from microcrystals grown in lipid cubic phases.Science 277,16761681.DOI: 10.1126/science.277.5332.1676
  • 37
    Peroutka S.J. & Howell T.A. (1994) The molecular evolution of G protein-coupled receptors : focus on 5-hydroxytryptamine receptors.Neuropharmacology 33,319324.
  • 38
    Plassat J., Amlaiky N., Hen R. (1993) Molecular cloning of a mammalian serotonin receptor that activates adenylate cyclase.Mol. Pharmacol. 44,229236.
  • 39
    Pritchett D.B., Bach A.W., Wozny M., Taleb O., Dal Toso R., Shih J.C., Seeburg P.H. (1988) Structure and functional expression of cloned rat serotonin 5HT-2 receptor.EMBO J. 7,41354140.
  • 40
    Raymond J.R., Hnatowich M., Lefkowitz R.J., Caron M.G. (1990) Adrenergic receptors. Models for regulation of signal transduction processes.Hypertension 15,119131.
  • 41
    Ruat M., Traiffort E., Leurs R., Tardivel-Lacombe J., Diaz J., Arrang J., Schwartz J. -C. (1993) Molecular cloning, characterization, and localization of a high-affinity serotonin receptor (5-HT7) activating cAMP formation. Proc. Natl. Acad. Sci. USA 90,85478551.
  • 42
    Saltzman A.G., Morse B., Whitman M.M., Ivanshchenko Y., Jaye M., Felder S. (1991) Cloning of the human serotonin 5-HT2 and 5-HT1C receptor subtypes.Biochem. Biophys. Res. Commun. 181,14691478.
  • 43
    Saudou F., Boschert U., Amlaiky N., Plassat J.L., Hen R. (1992) A family of Drosophila serotonin receptors with distinct intracellular signalling properties and expression patterns.EMBO J. 11,717.
  • 44
    Sharma A., Punhani T., Fone K.C.F. (1997) Distribution of the 5-hydroxytryptamine2C receptor protein in adult rat brain and spinal cord determined using a receptor-directed antibody : effect of 5,7-dihydroxytryptamine.Synapse 27,4556.DOI: 10.1002/(SICI)1098-2396(199709)27:1<45::AID-SYN5>3.0.CO;2-D
  • 45
    Strader C.D., Sigal I.S., Register R.B., Candelore M.R., Rands E., Dixon R.A.F. (1987) Identification of residues required for ligand binding to the beta-adrenergic receptor.Proc. Natl. Acad. Sci. USA 84,43844388.
  • 46
    Strader C.D., Sigal I.S., Candelore M.R., Rands E., Hill W.S., Dixon R.A.F. (1988) Conserved aspartic acid residues 79 and 113 of the beta-adrenergic receptor have different roles in receptor function.J. Biol. Chem. 263,1026710271.
  • 47
    Unwin P.N.T. & Henderson R. (1975) Molecular structure determination by electron microscopy of unstained crystalline specimens.J. Mol. Biol. 94,425440.
  • 48
    Von Zastrow M. & Kobilka B.K. (1992) Ligand-regulated internalization and recycling of human β2-adrenergic receptors between the plasma membrane and endosomes containing transferrin receptors. J. Biol. Chem. 267,35303538.
  • 49
    Von Zastrow M., Link R., Daunt D., Barsh G., Kobilka B. (1993) Subtype-specific differences in the intracellular sorting of G protein-coupled receptors.J. Biol. Chem. 268,763766.
  • 50
    Westphal R.S. & Sanders-Bush E. (1994) Reciprocal binding properties of 5-hydroxytryptamine type 2C receptor agonists and inverse agonists.Mol. Pharmacol. 46,937942.
  • 51
    Wilson I.A., Niman H.L., Houghten R.A., Cherenson A.R., Connolly M.L., Lerner R.A. (1984) The structure of an antigenic determinant in a protein.Cell 37,767768.
  • 52
    Witz P., Amlaiky N., Plassat J.L., Maroteaux L., Borrelli E., Hen R. (1990) Cloning and characterization of a Drosophila serotonin receptor that activates adenylate cyclase.Proc. Natl. Acad. Sci. USA 87,89408944.
  • 53
    Wolf W.A. & Schutz L.J. (1997) The serotonin 5-HT2C receptor is a prominent serotonin receptor in basal ganglia : evidence from functional studies on serotonin-mediated phosphoinositide hydrolysis.J. Neurochem. 69,14491458.
  • 54
    Yu L., Nguyen H., Le H., Bloem L.J., Kozak C.A., Hoffman B.J., Snutch T.P., Lester H.A., Davidson N., Lubbert H. (1991) The mouse 5-HT1C receptor contains eight hydrophobic domains and is X-linked.Brain Res. Mol. Brain Res. 11,143149.