Logo image
Back
Gain of function mutants reveal sites important for the interaction of the atypical inhibitors benztropine and bupropion with monoamine transporters
Journal article   Peer reviewed

Gain of function mutants reveal sites important for the interaction of the atypical inhibitors benztropine and bupropion with monoamine transporters

Ole V Mortensen and Susan G Amara
Journal of neurochemistry, v 98(5), pp 1531-1540
Sep 2006
DOI: https://doi.org/10.1111/j.1471-4159.2006.04060.x
PMID: 16923164
Featured in Collection :   UN Sustainable Development Goals @ Drexel

Abstract

Dopamine Plasma Membrane Transport Proteins - metabolism Fluoxetine - pharmacokinetics Mutagenesis, Site-Directed Dopamine Uptake Inhibitors - pharmacology Cercopithecus aethiops Dopamine - pharmacokinetics Models, Molecular Serine - genetics Dopamine Plasma Membrane Transport Proteins - genetics Binding, Competitive - drug effects Dose-Response Relationship, Drug Animals Drug Interactions Transfection - methods Alanine - genetics Norepinephrine Plasma Membrane Transport Proteins - genetics Fluoxetine - analogs & derivatives Radioligand Assay - methods Biological Transport - drug effects Bupropion - pharmacology Benztropine - pharmacology Norepinephrine Plasma Membrane Transport Proteins - metabolism COS Cells Tritium - pharmacokinetics
Two atypical inhibitors of the dopamine transporter, benztropine, used in the treatment of Parkinson's disease, and bupropion, used as an antidepressant, show very different psychostimulant effects when compared with another inhibitor, cocaine. Taking advantage of the differential sensitivity of the dopamine and the norepinephrine transporters (DAT and NET) to benztropine and bupropion, we have used site-directed mutagenesis to produce gain-of-function mutants in NET which demonstrate that Ala279 in the trans-membrane domain 5 (TM5) and Ser359 in the TM7 of DAT are responsible for the higher sensitivity of DAT to both bupropion and benztropine. Substitution of these two DAT residues into the NET background does not alter the potency of NET-selective inhibitors, such as desipramine. The results from experiments examining the ability of DAT-selective inhibitors to displace [3H]nisoxetine binding in NET gain-of-function mutants suggest that Ser359 contributes to the initial binding of the inhibitor, and that Ala279 may influence subsequent steps involved in the blockade of translocation. Thus, these studies begin to identify residues that are important for the unique molecular interactions of benztropine and bupropion with the DAT, and that ultimately may contribute to the distinct behavioral actions of these drugs.

Metrics

16 Record Views
14 citations in Web of Science
13 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#3 Good Health and Well-Being

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Web of Science research areas
Biochemistry & Molecular Biology
Neurosciences
Logo image