HTR3A explained

5-hydroxytryptamine receptor 3A is a protein that in humans is encoded by the HTR3A gene.^{[1] [2]}

The product of this gene belongs to the ligand-gated ion channel receptor superfamily. This gene encodes subunit A of the type 3 receptor for 5-hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. This receptor causes fast, depolarizing responses in neurons after activation. The A subunit is the only one that can be expressed alone and forms homomers with a very low single channel conductance of 0.6pS. When combined with the B subunit and expressed as a heteromer, the single channel conductance increases immensely. Alternatively spliced transcript variants encoding different isoforms have been identified.^[3]

See also

• 5-HT3 receptor

Further reading

• Miyake A, Mochizuki S, Takemoto Y, Akuzawa S . Molecular cloning of human 5-hydroxytryptamine3 receptor: heterogeneity in distribution and function among species. . Mol. Pharmacol. . 48 . 3 . 407–416 . 1995 . 7565620 .
• Uetz P, Abdelatty F, Villarroel A, etal . Organisation of the murine 5-HT3 receptor gene and assignment to human chromosome 11. . FEBS Lett. . 339 . 3 . 302–306 . 1994 . 8112471 . 10.1016/0014-5793(94)80435-4 . 28979681 . free . 1994FEBSL.339..302U .
• Belelli D, Balcarek JM, Hope AG, etal . Cloning and functional expression of a human 5-hydroxytryptamine type 3AS receptor subunit. . Mol. Pharmacol. . 48 . 6 . 1054–1062 . 1996 . 8848005 .
• Brüss M, Göthert M, Hayer M, Bönisch H . Molecular cloning of alternatively spliced human 5-HT3 receptor cDNAs. . Ann. N. Y. Acad. Sci. . 861 . 234–235 . 1999 . 9928262 . 10.1111/j.1749-6632.1998.tb10196.x .
• Davies PA, Pistis M, Hanna MC, etal . The 5-HT3B subunit is a major determinant of serotonin-receptor function. . Nature . 397 . 6717 . 359–363 . 1999 . 9950429 . 10.1038/16941 . 1999Natur.397..359D . 4401851 .
• Brüss M, Eucker T, Göthert M, Bönisch H . Exon-intron organization of the human 5-HT3A receptor gene. . Neuropharmacology . 39 . 2 . 308–315 . 2000 . 10670426 . 10.1016/S0028-3908(99)00116-1 . 6002534 .
• Marazziti D, Betti L, Giannaccini G, etal . Distribution of [3H]GR65630 binding in human brain postmortem. . Neurochem. Res. . 26 . 3 . 187–190 . 2002 . 11495540 . 10.1023/A:1010939530412 . 2548479 .
• Spier AD, Lummis SC . Immunological characterization of 5-HT3 receptor transmembrane topology. . J. Mol. Neurosci. . 18 . 3 . 169–178 . 2003 . 12059035 . 10.1385/JMN:18:3:169 . 25754984 .
• Boyd GW, Low P, Dunlop JI, etal . Assembly and cell surface expression of homomeric and heteromeric 5-HT3 receptors: the role of oligomerization and chaperone proteins. . Mol. Cell. Neurosci. . 21 . 1 . 38–50 . 2002 . 12359150 . 10.1006/mcne.2002.1160 . 37832903 .
• Hapfelmeier G, Haseneder R, Lampadius K, etal . Cloned human and murine serotonin(3A) receptors expressed in human embryonic kidney 293 cells display different single-channel kinetics. . Neurosci. Lett. . 335 . 1 . 44–48 . 2003 . 12457738 . 10.1016/S0304-3940(02)01156-4 . 35192275 .
• Strausberg RL, Feingold EA, Grouse LH, etal . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–16903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . free .
• Pick H, Preuss AK, Mayer M, etal . Monitoring expression and clustering of the ionotropic 5HT3 receptor in plasma membranes of live biological cells . Biochemistry . 42 . 4 . 877–884 . 2003 . 12549905 . 10.1021/bi026576d .
• Choi S, Lee JH, Oh S, etal . Effects of ginsenoside Rg2 on the 5-HT3A receptor-mediated ion current in Xenopus oocytes . Mol. Cells . 15 . 1 . 108–113 . 2003 . 10.1016/S1016-8478(23)13715-0 . 12661769 . free .
• Boyd GW, Doward AI, Kirkness EF, etal . Cell surface expression of 5-hydroxytryptamine type 3 receptors is controlled by an endoplasmic reticulum retention signal . J. Biol. Chem. . 278 . 30 . 27681–27687 . 2003 . 12750374 . 10.1074/jbc.M304938200 . free .
• Sun H, Hu XQ, Moradel EM, etal . Modulation of 5-HT3 receptor-mediated response and trafficking by activation of protein kinase C . J. Biol. Chem. . 278 . 36 . 34150–34157 . 2003 . 12791692 . 10.1074/jbc.M303584200 . free .
• Maksay G, Bikádi Z, Simonyi M . Binding interactions of antagonists with 5-hydroxytryptamine3A receptor models . J. Recept. Signal Transduct. Res. . 23 . 2–3 . 255–270 . 2004 . 14626451 . 10.1081/RRS-120025568 . 26799630 .
• Kaiser R, Tremblay PB, Sezer O, etal . Investigation of the association between 5-HT3A receptor gene polymorphisms and efficiency of antiemetic treatment with 5-HT3 receptor antagonists . Pharmacogenetics . 14 . 5 . 271–278 . 2004 . 15115912 . 10.1097/00008571-200405000-00001 .
• Panicker S, Cruz H, Arrabit C, etal . Minimal structural rearrangement of the cytoplasmic pore during activation of the 5-HT3A receptor . J. Biol. Chem. . 279 . 27 . 28149–28158 . 2004 . 15131114 . 10.1074/jbc.M403545200 . free .

Notes and References

1. Weiss B, Mertz A, Schrock E, Koenen M, Rappold G . Assignment of a human homolog of the mouse Htr3 receptor gene to chromosome 11q23.1-q23.2 . Genomics . 29 . 1 . 304–305 . Feb 1996 . 8530095 . 10.1006/geno.1995.1254 .
2. Kelley SP, Dunlop JI, Kirkness EF, Lambert JJ, Peters JA . A cytoplasmic region determines single-channel conductance in 5-HT3 receptors . Nature . 424 . 6946 . 321–324 . Jul 2003 . 12867984 . 10.1038/nature01788 . 2003Natur.424..321K . 4417817 . subscription .
3. Web site: Entrez Gene: HTR3A 5-hydroxytryptamine (serotonin) receptor 3A.