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Mapping Dysfunctional Protein-Protein Interactions in Disease
Published on: October 24, 2025
The PI(3)P interactome from a colon cancer cell
Bruno Catimel1, Eugene Kapp, Meng-Xin Yin
1Ludwig Institute for Cancer Research, Melbourne-Parkville Branch, Post Office Box 2008 Royal Melbourne Hospital, Victoria 3050, Australia. Bruno.catimel@ludwig.edu.au
Journal of Proteomics
|February 19, 2013
Summary
Researchers identified 681 proteins interacting with phosphatidylinositol 3-phosphate (PI(3)P), revealing its crucial roles in cell signaling, endocytosis, and cell division.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Phosphoinositides, including phosphatidylinositol 3-phosphate (PI(3)P), are critical signaling lipids.
- Understanding the PI(3)P interactome is essential for elucidating cellular processes.
Purpose of the Study:
- To comprehensively analyze the PI(3)P interactome.
- To identify proteins and protein complexes that bind to PI(3)P.
- To determine the functional significance of PI(3)P interactions.
Main Methods:
- Affinity purification using an ω-amino analogue of PI(3)P immobilized on beads.
- Mass spectrometry (LC/MS/MS) for protein identification.
- Bioinformatic analysis for protein domain and pathway enrichment.
Main Results:
- Identified 681 proteins and protein complexes interacting with PI(3)P from colonic carcinoma cell line extracts.
- Detected enrichment of PI(3)P-binding domains (FYVE, PX, PH), GTPases, kinases, and signaling proteins.
- Functional analysis revealed PI(3)P's involvement in endocytosis, vesicular trafficking, signaling, cell division, and cytokinesis.
Conclusions:
- This study presents the first detailed assessment of the PI(3)P interactome.
- PI(3)P plays a significant role in endocytosis, vesicular trafficking, intracellular signaling, and cytokinesis.
- The findings suggest potential PI(3)P specificities for future research.
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