Probing dopamine transporter structure and function by Zn2+-site engineering.
The biogenic amine transporters belong to the class of Na+/Cl--coupled solute carriers and include the transporters for dopamine (DAT), norepinephrine (NET), and serotonin (SERT). These transporters are the primary targets for the action of many psychoactive compounds including the most commonly used antidepressants as well as widely abused drugs such as cocaine and amphetamines. In spite of their pharmacological importance, still little is known about their higher structural organization and the molecular mechanisms underlying the substrate translocation process. In this review, it will be described how we have used Zn2+-binding sites as a tool to probe the structure and function of Na+/Cl--coupled biogenic amine transporters with specific focus on the human DAT (hDAT). The work has not only led to the definition of the first structural constrains in the tertiary structure of this class of transporters, but also allowed inferences about conformational changes accompanying substrate translocation and residues critical for regulating the equilibrium between different functional states in the transport cycle.
Loland
Claus Juul
CJ
The Molecular Neuropharmacology Group, Department of Pharmacology, The Panum Institute 18.6, University of Copenhagen, DK-2200 Copenhagen N, Denmark. clausjuul@neuropharm.ku.dk
Norgaard-Nielsen
Kristine
K
Gether
Ulrik
U
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites / Q000502:physiology; D050483:Dopamine Plasma Membrane Transport Proteins; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D015202:Protein Engineering / Q000379:methods*; D013329:Structure-Activity Relationship; D015032:Zinc / Q000737:chemistry* / Q000378:metabolism*
D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493214:SLC6A3 protein, human; D015032:Zinc