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Co-immunoprecipitation Assay for Studying Functional Interactions Between Receptors and Enzymes
Published on: September 28, 2018
CD247 can bind SHC1, no matter if CD247 is phosphorylated
Tao Liu1, Fangjin Chen, Ning Tang
1State Key Laboratory of Proteomics, Department of Neurobiology, Institute of Basic Medical Sciences, Beijing 100850, PR China.
Journal of Molecular Recognition : JMR
|February 21, 2009
Summary
Src homology 2 domain-containing transforming protein C1 (SHC1) binds non-phosphorylated CD247 weakly, preparing for T cell receptor stimulation. Phosphorylation enhances SHC1-CD247 binding through electrostatic interactions, crucial for T cell signaling.
Area of Science:
- Immunology
- Molecular Biology
- Computational Biology
Background:
- Src homology 2 domain-containing transforming protein C1 (SHC1) interacts with the T cell receptor (TCR) CD247 chain upon phosphorylation.
- The precise mechanism by which CD247 phosphorylation facilitates SHC1 binding remains unclear.
Purpose of the Study:
- To elucidate the molecular interactions between SHC1's SH2 domain and both non-phosphorylated and phosphorylated CD247.
- To understand the role of CD247 phosphorylation in regulating SHC1 binding dynamics.
Main Methods:
- Molecular dynamics (MD) simulations comparing SHC1 SH2 domain interaction with CD247 and phosphorylated CD247.
- Affinity pull-down experiments to validate simulation findings.
Main Results:
- SHC1's SH2 domain binds to non-phosphorylated CD247, albeit weakly, forming a folded conformation.
- Phosphorylation of CD247 induces an extended conformation, leading to strong SHC1 binding via electrostatic interactions.
- Non-phosphorylated CD247 acts as a pre-recruitment mechanism for SHC1.
Conclusions:
- CD247 phosphorylation is a key regulator of SHC1 binding affinity, essential for TCR signaling.
- The study highlights the utility of MD simulations in dissecting phosphorylation-dependent protein interactions.
- Pre-binding of SHC1 to non-phosphorylated CD247 may prime T cells for rapid activation upon TCR stimulation.
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