title: Functional identification and molecular cloning of a human brain vesicle monoamine transporter.
abstract: A vesicle monoamine transporter was functionally identified, molecularly cloned, and characterized from a human substantia nigra cDNA library. The ATP-dependent transport of 5-[3H]hydroxytryptamine ([3H]5-HT) by digitonin-permeabilized fibroblasts expressing the vesicle monoamine/H+ antiporter in culture exhibited a Km of 0.55 microM. Reserpine and tetrabenazine, inhibitors of two monoamine binding sites, effectively blocked [3H]5-HT accumulation with Ki values of 34 and 78 nM, respectively. Pretreatment of cells with as little as 10 nM reserpine in the presence of ATP abolished uptake. The rank order for substrate inhibition of [3H]5-HT uptake for both the previously reported rat vMAT1 and the human transporter clone followed the order 5-HT > dopamine > epinephrine > norepinephrine > 1-methyl-4-phenylpyridinium > 2-phenylethylamine > histamine. The virtually identical transport characteristics of rvMAT1 and hvMAT1 confirm the relevance of neuropharmacological studies of rat brain biogenic amine uptake and storage to human brain neurochemistry.
authors.affiliation: Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, Maryland.
authors.forename: J D
authors.initials: JD
authors.lastname: Erickson
authors.forename: L E
authors.initials: LE
authors.lastname: Eiden
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001667:Binding, Competitive; D015306:Biogenic Monoamines / Q000378:metabolism / Q000494:pharmacology; D001921:Brain / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005347:Fibroblasts / Q000378:metabolism; D015723:Gene Library; D006023:Glycoproteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D008961:Models, Structural; D008969:Molecular Sequence Data; D009479:Neuropeptides; D017433:Protein Structure, Secondary; D051381:Rats; D012110:Reserpine / Q000494:pharmacology; D013378:Substantia Nigra / Q000378:metabolism*; D013747:Tetrabenazine / Q000494:pharmacology; D050492:Vesicular Biogenic Amine Transport Proteins; D050493:Vesicular Monoamine Transport Proteins
chemical_list: D015306:Biogenic Monoamines; D018076:DNA, Complementary; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009479:Neuropeptides; C493449:SLC18A1 protein, human; C493452:SLC18A2 protein, human; C493451:Slc18a1 protein, rat; D050492:Vesicular Biogenic Amine Transport Proteins; D050493:Vesicular Monoamine Transport Proteins; D012110:Reserpine; D000255:Adenosine Triphosphate; D013747:Tetrabenazine