β-arrestin signalling and bias in hormone-responsive GPCRs

Area of Science:

• Endocrinology
• Molecular Cell Biology
• Pharmacology

Background:

• G protein-coupled receptors (GPCRs) are key mediators of hormonal signaling.
• Traditional models viewed GPCR activation as a simple two-state process involving G proteins.
• Emerging evidence highlights complex signaling arrays, including G protein-independent pathways.

Purpose of the Study:

• To review endocrine-related GPCRs, focusing on β-arrestin recruitment and signaling.
• To discuss the role of β-arrestin-mediated transduction in endocrine systems.
• To explore ligand-selective signaling (pharmacological bias) in the context of GPCRs.

Main Methods:

• Literature review of existing evidence on GPCRs, β-arrestins, and endocrine signaling.
• Analysis of advances in GPCR structural biology and biophysics.
• Discussion of emerging concepts in β-arrestin-mediated transduction.

Main Results:

• GPCRs engage in diverse transduction mechanisms beyond G proteins, notably involving β-arrestins.
• β-arrestin recruitment to activated GPCRs mediates significant signaling pathways.
• Ligand-selective signaling, or pharmacological bias, is a key concept supported by structural and biophysical data.

Conclusions:

• β-arrestins play a critical role in GPCR signaling, offering new therapeutic avenues.
• Understanding β-arrestin-mediated pathways in endocrine systems is crucial for addressing pathophysiological implications.
• Biased ligands and receptor modifications present opportunities for selective modulation of GPCR activity.