Related Experiment Video

Updated: Jan 6, 2026

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

Published on: February 20, 2018

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Below the Surface: IGF-1R Therapeutic Targeting and Its Endocytic Journey

Caitrin Crudden1,2, Dawei Song3, Sonia Cismas4

  • 1Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden. c.crudden@amsterdamumc.nl.

Cells
|October 12, 2019
PubMed

Insights

Receptor endocytosis is not just for signal termination but actively regulates cell signaling. The endosome acts as a platform, controlling receptor localization and function, impacting biological outcomes.

Area of Science:

  • Cell biology
  • Molecular signaling
  • Cancer research

Background:

  • Ligand-activated plasma membrane receptors internalize via endocytosis.
  • The endosomal sorting apparatus processes receptors and ligands for recycling or degradation.
  • Traditionally, endocytosis was viewed primarily for signal termination.

Purpose of the Study:

  • To explore the emerging paradigm of endocytosis as a regulator of receptor signaling.
  • To discuss the role of the endosomal platform in governing receptor function.
  • To examine this perspective in the context of the insulin-like growth factor type 1 receptor (IGF-1R) in cancer.

Main Methods:

  • Review of current literature on receptor endocytosis and signaling.
  • Analysis of the endosomal platform's role in spatial and temporal receptor signaling.
  • Focus on the insulin-like growth factor type 1 receptor (IGF-1R) as a model.

Main Results:

  • Endocytosis is now understood to govern the spatial and temporal aspects of receptor signaling.
  • The endosome acts as a master regulator, controlling receptor localization, post-translational modifications, and scaffolding.
  • This endosomal platform dictates how cells interpret and translate receptor signals into biological effects.

Conclusions:

  • The endosomal platform is a critical regulatory hub for receptor signaling, extending beyond signal termination.
  • Understanding this paradigm is crucial for interpreting cellular responses to receptor activation.
  • This perspective offers new insights for developing targeted cancer therapies, particularly for IGF-1R.
Keywords:
GPCRRTKbiased signalingendocytosisendosomeinsulin receptorinsulin-like growth factor type 1 receptorinternalizationubiquitinationβ-arrestin

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