Related Experiment Video

Updated: Dec 16, 2025

Parallel Interrogation of β-Arrestin2 Recruitment for Ligand Screening on a GPCR-Wide Scale using PRESTO-Tango Assay
09:03

Parallel Interrogation of β-Arrestin2 Recruitment for Ligand Screening on a GPCR-Wide Scale using PRESTO-Tango Assay

Published on: March 10, 2020

13.4K

Phosphorylated peptide of G protein-coupled receptor induces dimerization in activated arrestin

Andreas M Stadler1,2, Joachim Granzin3, Anneliese Cousin3

  • 1Jülich Centre for Neutron Science (JCNS-1), Institute of Complex Systems (ICS-1), Forschungszentrum Jülich, 52425, Jülich, Germany.

Scientific Reports
|July 4, 2020
PubMed

Insights

Visual arrestin variants p44 and R175E, unlike wild type, dimerize upon binding phosphorylated rhodopsin. This receptor-induced oligomerization suggests new roles for arrestin function in cellular signaling pathways.

Area of Science:

  • Molecular Biology
  • Structural Biology
  • Biochemistry

Background:

  • G-protein-coupled receptor (GPCR) signaling termination relies on C-terminal phosphorylation and arrestin binding.
  • Arrestin-1 in the visual system inactivates phototransduction by binding phosphorylated rhodopsin.

Purpose of the Study:

  • Investigate the binding of a synthetic rhodopsin phosphopeptide to active visual arrestin-1 variants (p44 and R175E).
  • Determine the solution structure and oligomerization state of these arrestin variants upon phosphopeptide binding.

Main Methods:

  • Small angle X-ray scattering (SAXS) for solution structure analysis.
  • Size exclusion chromatography (SEC) to assess oligomerization states.
  • Utilized a synthetic phosphopeptide of bovine rhodopsin (residues 323-348).

Main Results:

  • Unlike wild-type arrestin-1, the p44 splice variant and R175E mutant arrestins are monomeric in solution.
  • Both arrestin variants demonstrated dimerization in the presence of the rhodopsin phosphopeptide.
  • This is the first report of receptor-induced oligomerization in arrestin.

Conclusions:

  • Receptor binding induces oligomerization in specific visual arrestin-1 variants.
  • Arrestin oligomerization may play a significant role in cellular arrestin function.
  • Findings have implications for all arrestin isoforms due to conserved activation mechanisms.

More Related Videos

Characterization of G Protein-coupled Receptors by a Fluorescence-based Calcium Mobilization Assay11:49

Characterization of G Protein-coupled Receptors by a Fluorescence-based Calcium Mobilization Assay

Published on: July 28, 2014

41.3K
A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators07:41

A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators

Published on: February 20, 2018

9.3K

Related Concept Videos

Amplifying Signals via Enzymatic Cascade01:22

Amplifying Signals via Enzymatic Cascade

When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze...
16.6K
Activation and Inactivation of G Proteins01:22

Activation and Inactivation of G Proteins

Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high...
10.2K
Assembly of Signaling Complexes01:30

Assembly of Signaling Complexes

Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
6.4K
IP3/DAG Signaling Pathway01:11

IP3/DAG Signaling Pathway

Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the  phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and...
13.9K
G-protein Coupled Receptors01:21

G-protein Coupled Receptors

G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
130.8K
GPCRs Regulate Adenylyl Cylase Activity01:09

GPCRs Regulate Adenylyl Cylase Activity

Some GPCRs transmit signals through adenylyl cyclase (AC), a transmembrane enzyme. AC helps synthesize second messenger cyclic adenosine monophosphate (cAMP). AC catalyzes cyclization reaction and converts ATP to cAMP by releasing a pyrophosphate. The pyrophosphate is further hydrolyzed to phosphate by the enzyme pyrophosphatase, which drives cAMP synthesis to completion. However, cAMP is rapidly degraded to 5′ AMP by the enzymes phosphodiesterase (PDE), preventing overstimulation of...
7.0K