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Updated: May 19, 2026
09:36
Recombinant α- β- and γ-Synucleins Stimulate Protein Phosphatase 2A Catalytic Subunit Activity in Cell Free Assays
Published on: August 13, 2017
γ-Synuclein interacts with phospholipase Cβ2 to modulate G protein activation
Urszula Golebiewska1, Yuanjian Guo, Narindra Khalikaprasad
1Department of Physiology & Biophysics, Stony Brook University, Stony Brook, New York, United States of America.
Plos One
|August 21, 2012
Summary
Gamma-synuclein interacts with Phospholipase Cβ2 (PLCβ2) in breast cancer cells, inhibiting its activity. G protein activation can overcome this inhibition, suggesting a role for gamma-synuclein in regulating PLCβ2 signaling.
Area of Science:
- Molecular biology
- Cell signaling
- Cancer research
Background:
- Phospholipase Cβ2 (PLCβ2) generates calcium signals and is upregulated in breast tumors.
- Gamma-synuclein (breast cancer specific gene protein 1) expression parallels PLCβ2 in breast cancer, but its function is unknown.
Purpose of the Study:
- To investigate the interaction between gamma-synuclein and PLCβ2.
- To determine if gamma-synuclein affects PLCβ2 activity.
Main Methods:
- Co-immunoprecipitation and co-immunofluorescence assays.
- In vitro binding assays using purified proteins.
- Protease digestion and mass spectrometry.
- Enzyme activity assays.
Main Results:
- Gamma-synuclein and PLCβ2 associate in breast cancer cell lines and in vitro.
- Gamma-synuclein binds to the Gαq binding site on PLCβ2, inhibiting its catalytic activity by blocking product release.
- Gαq and Gβγ can overcome gamma-synuclein-mediated inhibition of PLCβ2.
Conclusions:
- Gamma-synuclein interacts with PLCβ2 and modulates its activity.
- This interaction plays a role in G protein-mediated activation of PLCβ2 in breast cancer.
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