Genetically encoded photocrosslinkers locate the high-affinity binding site of antidepressant drugs in the human serotonin transporter

Research output: Contribution to journalJournal articleResearchpeer-review

Hafsteinn Rannversson, Jacob Andersen, Lena Sørensen Hall, Benny Bang-Andersen, Minyoung Park, Thomas Huber, Thomas P Sakmar, Kristian Strømgaard

Despite the well-established role of the human serotonin transporter (hSERT) in the treatment of depression, the molecular details of antidepressant drug binding are still not fully understood. Here we utilize amber codon suppression in a membrane-bound transporter protein to encode photocrosslinking unnatural amino acids (UAAs) into 75 different positions in hSERT. UAAs are incorporated with high specificity, and functionally active transporters have similar transport properties and pharmacological profiles compared with wild-type transporters. We employ ultraviolet-induced crosslinking with p-azido-L-phenylalanine (azF) at selected positions in hSERT to map the binding site of imipramine, a prototypical tricyclic antidepressant, and vortioxetine, a novel multimodal antidepressant. We find that the two antidepressants crosslink with azF incorporated at different positions within the central substrate-binding site of hSERT, while no crosslinking is observed at the vestibular-binding site. Taken together, our data provide direct evidence for defining the high-affinity antidepressant binding site in hSERT.

Original languageEnglish
Article number11261
JournalNature Communications
Volume7
Pages (from-to)1-9
Number of pages9
ISSN2041-1723
DOIs
Publication statusPublished - 19 Apr 2016

    Research areas

  • Amino Acids, Antidepressive Agents, Binding Sites, Binding, Competitive, Depression, Humans, Models, Molecular, Molecular Structure, Mutation, Phenylalanine, Photochemical Processes, Protein Binding, Protein Structure, Tertiary, Serotonin Plasma Membrane Transport Proteins, Ultraviolet Rays, Journal Article, Research Support, Non-U.S. Gov't

ID: 169437895