G protein-independent, arrestin-dependent signaling is a paradigm that broadens the signaling scope of G protein-coupled receptors (GPCRs) beyond G proteins for numerous biological processes. However, arrestin signaling in the collective absence of functional G proteins has never been demonstrated. Here we achieve a state of "zero functional G" at the cellular level using HEK293 cells depleted by CRISPR/Cas9 technology of the Gs/q/12 families of Gα proteins, along with pertussis toxin-mediated inactivation of Gi/o. Together with HEK293 cells lacking β-arrestins ("zero arrestin"), we systematically dissect G protein- from arrestin-driven signaling outcomes for a broad set of GPCRs. We use biochemical, biophysical, label-free whole-cell biosensing and ERK phosphorylation to identify four salient features for all receptors at "zero functional G": arrestin recruitment and internalization, but - unexpectedly - complete failure to activate ERK and whole-cell responses. These findings change our understanding of how GPCRs function and in particular of how they activate ERK1/2.
CITATION STYLE
Grundmann, M., Merten, N., Malfacini, D., Inoue, A., Preis, P., Simon, K., … Kostenis, E. (2018). Lack of beta-arrestin signaling in the absence of active G proteins. Nature Communications, 9(1). https://doi.org/10.1038/s41467-017-02661-3
Mendeley helps you to discover research relevant for your work.