Azobenzene-diamides as Photopharmacological Ligands for Insect Ryanodine Receptor

Abstract

Photoresponsive ligands are powerful tool compounds for studying receptor function with spatiotemporal resolution. However, to the best of our knowledge, such a ligand is not available for the ryanodine receptor (RyR). Herein, we present a photochromic ligand (PCL) for insect RyR by decorating chlorantraniliprole (CHL) with photoswitchable azobenzene (AB). We demonstrated that one potent ligand, named ABCHL13, shows light-induced reversible trans-cis isomerization and 3.5-fold insecticidal activity decrease toward oriental armyworm (Mythimna separata) after UV-light irradiation, that is, trans-ABCH13 has higher activity than the cis-ABCH13. ABCHL13 enables optical control over intracellular Ca²⁺ release in dorsal unpaired median (DUM) neurons of M. separata and American cockroach (Periplaneta americana) and cardiac function of P. americana. Our results provide a first photopharmacological toolkit that is applicable to light-dependent regulation of RyR and heart beating.

Keywords: azobenzene; chlorantraniliprole; insect; photopharmacology; ryanodine receptor.