Kurt Han, Akyol Ali, Son Cagdas Devrim, Zheng Chen, Gado Irene, Meli Massimiliano, Ferrandi Erica Elisa, Bassanini Ivan, Vasile Francesca, Gurevich Vsevolod V, Nebol Aylin, Cagavi Esra, Morra Giulia, Sensoy Ozge
Istanbul Medipol University, Graduate School of Engineering and Natural Sciences, Istanbul, Turkey.
University of Cagliari, Department of Physics, Cittadella Universitaria, Monserrato (CA), Italy.
Commun Chem. 2025 Jul 1;8(1):194. doi: 10.1038/s42004-025-01581-4.
Excessive signaling by various GPCRs underlies a variety of human disorders. Suppression of GPCRs by "enhanced" arrestin mutants was proposed as therapy. We hypothesized that GPCR binding of endogenous arrestins can be increased by small molecules stabilizing pre-activated conformation. Using molecular dynamics, we identified potentially druggable pockets in pre-activated conformation of arrestin-3 and discovered a compound targeting one of these pockets. Saturation-transfer difference NMR data showed that the compound binds at the back loop of arrestin-3. FRET- and NanoBiT-based assays in living cells showed that the compound increased in-cell arrestin-3, but not arrestin-2, binding to basal β2-adrenergic receptor and its phosphorylation-deficient mutant, but not to muscarinic M2 receptor. These experiments demonstrated the feasibility of enhancing the binding of endogenous wild type arrestin-3 to GPCRs in a receptor-specific and arrestin-subtype selective manner.
各种G蛋白偶联受体（GPCR）的过度信号传导是多种人类疾病的基础。有人提出用“增强型”抑制蛋白突变体抑制GPCR作为治疗方法。我们假设内源性抑制蛋白与GPCR的结合可以通过稳定预激活构象的小分子来增加。利用分子动力学，我们在抑制蛋白-3的预激活构象中确定了潜在的可成药口袋，并发现了一种靶向其中一个口袋的化合物。饱和转移差异核磁共振数据表明该化合物结合在抑制蛋白-3的后环。基于活细胞的荧光共振能量转移（FRET）和纳米生物发光互补（NanoBiT）分析表明，该化合物增加了细胞内抑制蛋白-3与基础β2肾上腺素能受体及其磷酸化缺陷突变体的结合，但不增加与毒蕈碱M2受体的结合，而对抑制蛋白-2与这些受体的结合没有影响。这些实验证明了以受体特异性和抑制蛋白亚型选择性的方式增强内源性野生型抑制蛋白-3与GPCR结合的可行性。
