1. Academic Validation
  2. Structure-Based Design of High-Affinity Fluorescent Probes for the Neuropeptide Y Y1 Receptor

Structure-Based Design of High-Affinity Fluorescent Probes for the Neuropeptide Y Y1 Receptor

  • J Med Chem. 2022 Mar 24;65(6):4832-4853. doi: 10.1021/acs.jmedchem.1c02033.
Christoph Müller 1 Jakob Gleixner 1 Maris-Johanna Tahk 2 Sergei Kopanchuk 2 Tõnis Laasfeld 2 Michael Weinhart 3 Dieter Schollmeyer 4 Martin U Betschart 5 Steffen Lüdeke 5 Pierre Koch 1 Ago Rinken 2 Max Keller 1
Affiliations

Affiliations

  • 1 Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany.
  • 2 Institute of Chemistry, Faculty of Bioorganic Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia.
  • 3 Institute of Inorganic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany.
  • 4 Department of Chemistry, Johannes-Gutenberg-University Mainz, Düsbergweg 10-14, 55099 Mainz, Germany.
  • 5 Institute of Pharmaceutical Sciences, University of Freiburg, Albertstrasse 25, 79104 Freiburg, Germany.
Abstract

The recent crystallization of the neuropeptide Y Y1 receptor (Y1R) in complex with the argininamide-type Y1R selective antagonist UR-MK299 (2) opened up a new approach toward structure-based design of nonpeptidic Y1R ligands. We designed novel fluorescent probes showing excellent Y1R selectivity and, in contrast to previously described fluorescent Y1R ligands, considerably higher (∼100-fold) binding affinity. This was achieved through the attachment of different fluorescent dyes to the diphenylacetyl moiety in 2 via an amine-functionalized linker. The fluorescent ligands exhibited picomolar Y1R binding affinities (pKi values of 9.36-9.95) and proved to be Y1R antagonists, as validated in a Fura-2 calcium assay. The versatile applicability of the probes as tool compounds was demonstrated by flow cytometry- and fluorescence anisotropy-based Y1R binding studies (saturation and competition binding and association and dissociation kinetics) as well as by widefield and total internal reflection fluorescence (TIRF) microscopy of live tumor cells, revealing that fluorescence was mainly localized at the plasma membrane.

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