Molecular cloning, expression and characterization of a bovine serotonin transporter.
The serotonin transporter (SERT) is a member of a highly homologous family of sodium/chloride dependent neurotransmitter transporters responsible for reuptake of biogenic amines from the extracellular fluid. SERT constitutes the pharmacological target of several clinically important antidepressants. Here we report the molecular cloning of SERT from the bovine species. Translation of the nucleotide sequence revealed 44 amino acid differences compared to human SERT. When transiently expressed in HeLa cells and compared with rat and human SERTs the K(m) value for uptake was increased 2-fold. V(max) and B(max) were both increased about 4-fold indicating the turnover number is conserved. The pharmacological profile revealed a decreased sensitivity towards imipramine, desipramine, citalopram, fluoxetine and paroxetine compared with human SERT, while the sensitivity towards 3, 4-methylenedioxymethamphetamine (MDMA) was mainly unchanged. RT-PCR amplification of RNA from different tissues demonstrated expression of SERT in placenta, brain stem, bone marrow, kidney, lung, heart, adrenal gland, liver, parathyroid gland, thyroid gland, small intestine and pancreas.
Department of Biological Psychiatry, Psychiatric University Hospital, Skovagervej 2, 8240 Risskov, Denmark.
O V
OV
Mortensen
A S
AS
Kristensen
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G
Rudnick
O
O
Wiborg
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D002417:Cattle; D015283:Citalopram / Q000494:pharmacology; D003001:Cloning, Molecular; D003891:Desipramine / Q000494:pharmacology; D005260:Female; D005473:Fluoxetine / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D007099:Imipramine / Q000494:pharmacology; D007700:Kinetics; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000494:pharmacology; D009419:Nerve Tissue Proteins; D009928:Organ Specificity; D017374:Paroxetine / Q000494:pharmacology; D010802:Phylogeny; D011247:Pregnancy; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012701:Serotonin / Q000378:metabolism; D050486:Serotonin Plasma Membrane Transport Proteins; D014162:Transfection
D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; C493232:Slc6a4 protein, rat; D005473:Fluoxetine; D015283:Citalopram; D012701:Serotonin; D017374:Paroxetine; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D007099:Imipramine; D003891:Desipramine