Discovery of a dual Ras and ARF6 inhibitor from a GPCR endocytosis screen

Giubilaro, Jenna; Schuetz, Doris A.; Stepniewski, Tomasz Maciej, 1988-; Namkung, Yoon; Khoury, Etienne; Lara Márquez, Mónica; Campbell, Shirley; Beautrait, Alexandre; Armando, Sylvain; Radresa, Olivier; Duchaine, Jean; Lamarche Vane, Nathalie; Claing, Audrey; Selent, Jana; Bouvier, Michel; Marinier, Anne; Laporte, Stéphane A.

doi:http://dx.doi.org/10.1038/s41467-021-24968-y

Discovery of a dual Ras and ARF6 inhibitor from a GPCR endocytosis screen

Citation

Giubilaro J, Schuetz DA, Stepniewski TM, Namkung Y, Khoury E, Lara-Márquez M, Campbell S, Beautrait A, Armando S, Radresa O, Duchaine J, Lamarche-Vane N, Claing A, Selent J, Bouvier M, Marinier A, Laporte SA. Discovery of a dual Ras and ARF6 inhibitor from a GPCR endocytosis screen. Nat Commun. 2021;12(1):4688. DOI: 10.1038/s41467-021-24968-y

Abstract

Internalization and intracellular trafficking of G protein-coupled receptors (GPCRs) play pivotal roles in cell responsiveness. Dysregulation in receptor trafficking can lead to aberrant signaling and cell behavior. Here, using an endosomal BRET-based assay in a high-throughput screen with the prototypical GPCR angiotensin II type 1 receptor (AT1R), we sought to identify receptor trafficking inhibitors from a library of ~115,000 small molecules. We identified a novel dual Ras and ARF6 inhibitor, which we named Rasarfin, that blocks agonist-mediated internalization of AT1R and other GPCRs. Rasarfin also potently inhibits agonist-induced ERK1/2 signaling by GPCRs, and MAPK and Akt signaling by EGFR, as well as prevents cancer cell proliferation. In silico modeling and in vitro studies reveal a unique binding modality of Rasarfin within the SOS-binding domain of Ras. Our findings unveil a class of dual small G protein inhibitors for receptor trafficking and signaling, useful for the inhibition of oncogenic cellular responses.