Premium
Rational Design of Nanobody80 Loop Peptidomimetics: Towards Biased β 2 Adrenergic Receptor Ligands
Author(s) -
Martin Charlotte,
Moors Samuel L. C.,
Danielsen Mia,
Betti Cecilia,
Fabris Cecilia,
Sejer Pedersen Daniel,
Pardon Els,
Peyressatre Marion,
Fehér Krisztina,
Martins José C.,
Mosolff Mathiesen Jesper,
Morris May C.,
Devoogdt Nick,
Caveliers Vicky,
De Proft Frank,
Steyaert Jan,
Ballet Steven
Publication year - 2017
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201701321
Subject(s) - peptidomimetic , g protein coupled receptor , receptor , chemistry , stereochemistry , biophysics , binding site , intracellular , rational design , plasma protein binding , internalization , biochemistry , biology , peptide , genetics
G protein‐coupled receptors (GPCRs) play an important role in many cellular responses; as such, their mechanism of action is of utmost interest. To gain insight into the active conformation of GPCRs, the X‐ray crystal structures of nanobody (Nb)‐stabilized β 2 ‐adrenergic receptor (β 2 AR) have been reported. Nb80, in particular, is able to bind the intracellular G protein binding site of β 2 AR and stabilize the receptor in an active conformation. Within Nb80, the complementarity‐determining region 3 (CDR3) is responsible for most of the binding interactions. Hence, we hypothesized that peptidomimetics of the CDR3 loop might be sufficient for binding to the receptor, inhibiting the interaction of β 2 AR with intracellular GPCR interacting proteins (e.g., G proteins). Based on previous crystallographic data, a set of peptidomimetics were synthesized that, similar to the Nb80 CDR3 loop, adopt a β‐hairpin conformation. Syntheses, conformational analysis, binding and functional in vitro assays, as well as internalization experiments, were performed. We demonstrate that peptidomimetics can structurally mimic the CDR3 loop of a nanobody and its function by inhibiting G protein coupling as measured by partial inhibition of cAMP production.