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Updated: Nov 22, 2025
10:58
PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions
Published on: July 27, 2017
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Identification of Key Phospholipids That Bind and Activate Atypical PKCs
Suresh Velnati1,2, Sara Centonze1,2, Federico Girivetto1,2
1Department of Translational Medicine, University of Piemonte Orientale, 28100 Novara, Italy.
Biomedicines
|January 9, 2021
Summary
Atypical protein kinase C (PKC) isoforms, PKCζ and PKCι, interact with specific membrane lipids like phosphatidic acid and phosphatidylserine. Phosphatidylinositol-monophosphates uniquely bind and activate PKCι, revealing novel lipid-based regulation.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Atypical protein kinase C (PKC) isoforms, specifically PKCζ and PKCι/λ, lack regulation by calcium and diacylglycerol.
- Understanding the regulatory mechanisms of these atypical PKCs is crucial for elucidating their cellular functions.
Purpose of the Study:
- To investigate the interactions between atypical PKCs (PKCζ and PKCι) and various phospholipids.
- To determine the effects of these lipid interactions on the enzymatic activity of PKCζ and PKCι.
Main Methods:
- Lipid overlay assays were employed to systematically explore the binding of purified PKCζ and PKCι to different phospholipids.
- Kinase activity assays were performed to assess the functional impact of lipid binding on enzyme activity.
Main Results:
- Both PKCζ and PKCι demonstrated interactions with phosphatidic acid and phosphatidylserine.
- PKCι exhibited unique binding to phosphatidylinositol-monophosphates, including phosphatidylinositol 3-phosphate, 4-phosphate, and 5-phosphate.
- Phosphatidylinositol 4-phosphate specifically activated PKCι, whereas phosphatidic acid and phosphatidylserine modulated the activity of both isoforms.
Conclusions:
- Atypical PKC localization and activity are regulated by membrane lipids, distinct from those influencing conventional PKCs.
- Phosphatidylinositol-monophosphates play a specific role in the regulation of PKCι activity.
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