Agonist-Specific Recruitment of Arrestin Isoforms Differentially Modify Delta Opioid Receptor Function

A. A. A Pradhan , Julie Perroy (1) , W. M. M Walwyn , M. L. Smith , A. Vicente-Sanchez , L. Segura , A. Bana , B. L. Kieffer , C. J. J Evans

1 IGF - Institut de Génomique Fonctionnelle

Ligand-specific recruitment of arrestins facilitates functional selectivity of G-protein-coupled receptor signaling. Here, we describe agonist-selective recruitment of different arrestin isoforms to the delta opioid receptor in mice. A high-internalizing delta opioid receptor agonist (SNC80) preferentially recruited arrestin 2 and, in arrestin 2 knock-outs (KOs), we observed a significant increase in the potency of SNC80 to inhibit mechanical hyperalgesia and decreased acute tolerance. In contrast, the low-internalizing delta agonists (ARM390, JNJ20788560) preferentially recruited arrestin 3 with unaltered behavioral effects in arrestin 2 KOs. Surprisingly, arrestin 3 KO revealed an acute tolerance to these low-internalizing agonists, an effect never observed in wild-type animals. Furthermore, we examined delta opioid receptor-Ca(2+)channel coupling in dorsal root ganglia desensitized by ARM390 and the rate of resensitization was correspondingly decreased in arrestin 3 KOs. Live-cell imaging in HEK293 cells revealed that delta opioid receptors are in pre-engaged complexes with arrestin 3 at the cell membrane and that ARM390 strengthens this membrane interaction. The disruption of these complexes in arrestin 3 KOs likely accounts for the altered responses to low-internalizing agonists. Together, our results show agonist-selective recruitment of arrestin isoforms and reveal a novel endogenous role of arrestin 3 as a facilitator of resensitization and an inhibitor of tolerance mechanisms. SIGNIFICANCE STATEMENT: Agonists that bind to the same receptor can produce highly distinct signaling events and arrestins are a major mediator of this ligand bias. Here, we demonstrate that delta opioid receptor agonists differentially recruit arrestin isoforms. We found that the high-internalizing agonist SNC80 preferentially recruits arrestin 2 and knock-out (KO) of this protein results in increased efficacy of SNC80. In contrast, low-internalizing agonists (ARM390 and JNJ20788560) preferentially recruit arrestin 3 and, surprisingly, KO of arrestin 3 produces acute tolerance and impaired receptor resensitization to these agonists. Arrestin 3 is in pre-engaged complexes with the delta opioid receptor at the cell membrane and low-internalizing agonists promote this interaction. This study reveals a novel role for arrestin 3 as a facilitator of receptor resensitization.

Mots clés: Receptors; Opioid; Protein Isoforms; Female; Male; pain; Animals; Mice; Knockout; *Pain Perception; arrestin; Arrestins/*metabolism; Benzamides/*administration & dosage; Drug Tolerance; Hyperalgesia/*physiopathology; Piperazines/*administration & dosage; delta/*antagonists & inhibitors/*metabolism; resensitization; tolerance; DRG; GPCR

Domaines: Sciences du Vivant [q-bio]

A. A. A Pradhan, Julie Perroy, W. M. M Walwyn, M. L. Smith, A. Vicente-Sanchez, et al.. Agonist-Specific Recruitment of Arrestin Isoforms Differentially Modify Delta Opioid Receptor Function. Journal of Neuroscience, 2016, 36 (12), pp.3541--51. ⟨10.1523/JNEUROSCI.4124-15.2016⟩. ⟨hal-01936373⟩