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bioRxiv · 10.1101/2025.03.28.645988

FAST RESENSITIZATION OF G PROTEIN-COUPLED RECEPTORS REQUIRESTHEIR PI(4,5)P2-DEPENDENT SORTING INTO AN AP2 POSITIVE COMPARTMENT

Gulyas, G.·Baba, T.·Toth, D.·Inoue, A.·Balla, T.
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Abstract

G protein coupled receptors (GPCRs) are the target of about 35% of FDA-approved drugs, which underlines their importance in physiology and disease. Many GPCRs undergo rapid desensitization upon agonist activation, mediated by {beta}-arrestin binding to the phosphorylated receptors, which prevents their G protein coupling. How such receptors regain their G protein signaling competence is poorly understood. Using the AT1 angiotensin II receptor (AT1R), we show that its rapid re-sensitization requires the sorting of the receptors into an AP2-positive plasma membrane (PM) compartment without receptors having to be internalized. This process requires the scaffolding protein, EFR3 and a dedicated PI(4,5)P2 pool specifically produced by PIP5KA. While {beta}-arrestin 1 and -2 both can carry the receptors to the AP2 compartment, weaker binding of {beta}-arrestin 1 to the receptor allows some of the receptors to re-sensitize, while strong {beta}-arrestin 2 binding elicits stronger desensitization and directs the receptors for internalization. These results suggest that the rapid phase of re-sensitization of GPCRs occurs without their endocytosis and primarily takes place at the PM at specific steps during clathrin-coated pit maturation. Together with differences observed between the two {beta}-arrestins to interact with CCPs and the receptors, our data suggest that specific PI(4,5)P2 pools controlled by EFR3A and PIP5K1A determine the balance between {beta}-arrestin1 and -2 receptor interaction and delivery to the AP2 positive compartment, ultimately determining what fraction of the receptors regain their G protein signaling competence.

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Gulyas, G., Baba, T., Toth, D., Inoue, A., Balla, T.. 2025-04-01. FAST RESENSITIZATION OF G PROTEIN-COUPLED RECEPTORS REQUIRESTHEIR PI(4,5)P2-DEPENDENT SORTING INTO AN AP2 POSITIVE COMPARTMENT. https://doi.org/10.1101/2025.03.28.645988

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