PUBLICATION
Characterisation of the zebrafish serotonin transporter functionally links TM10 to the ligand binding site
- Authors
- Severinsen, K., Sinning, S., Müller, H.K., and Wiborg, O.
- ID
- ZDB-PUB-080228-4
- Date
- 2008
- Source
- Journal of neurochemistry 105(5): 1794-1805 (Journal)
- Registered Authors
- Keywords
- cocaine, danio rerio, imipramine, serotonin transporter, monoamine transporter
- MeSH Terms
-
- Species Specificity
- Biological Transport/genetics
- Serotonin Plasma Membrane Transport Proteins/chemistry*
- Serotonin Plasma Membrane Transport Proteins/genetics
- Serotonin Plasma Membrane Transport Proteins/metabolism*
- Serotonin Plasma Membrane Transport Proteins/physiology
- Binding Sites/genetics
- Zebrafish
- Zebrafish Proteins/chemistry*
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism*
- Zebrafish Proteins/physiology
- Animals
- Cell Membrane/chemistry
- Cell Membrane/genetics
- Cell Membrane/metabolism
- Molecular Sequence Data
- Ligands
- Amino Acid Sequence
- Cell Line
- Humans
- PubMed
- 18266934 Full text @ J. Neurochem.
Citation
Severinsen, K., Sinning, S., Müller, H.K., and Wiborg, O. (2008) Characterisation of the zebrafish serotonin transporter functionally links TM10 to the ligand binding site. Journal of neurochemistry. 105(5):1794-1805.
Abstract
The selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) act by inhibiting presynaptic reuptake of serotonin (5-HT) leading to elevated synaptic 5-HT concentrations. However, despite extensive efforts little is known about the protein-ligand interactions of SERT and inhibitors. To identify domains and individual amino acids important for ligand binding, we cloned the serotonin transporter from zebrafish, Danio rerio, (drSERT) and compared its pharmacological profile to that of the human serotonin transporter (hSERT) with respect to inhibition of [(3)H]5-HT uptake and [(3)H]-escitalopram binding in transiently transfected human embryonic kidney cells; HEK-293-MSR. Residues responsible for altered affinities inhibitors were pinpointed by generating cross-species chimeras and subsequent point mutations by site directed mutagenesis. drSERT has a higher affinity towards compounds of the imipramine class, desipramine in particular, exhibiting a 35-fold increased affinity compared to hSERT. drSERT has a 15-30-fold lower affinity towards cocaine and cocaine analogues. The differences in ligand recognition are shown to be primarily caused by interspecies differences in TM10 and were tracked down to three residues (Ala(505), Leu(506) and Ile(507)).
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping