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Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
Phosphoinositide 3-kinase-regulated adapters in lymphocyte activation
Ting-Ting Zhang1, Hongzhao Li, Samuel M Cheung
1Department of Immunology, University of Manitoba, Winnipeg, MB, Canada.
Immunological Reviews
|November 14, 2009
Summary
Phosphoinositide 3-kinases (PI3Ks) are crucial for lymphocyte activation. Adapter proteins like Bam32/DAPP1 and SKAPs link PI3K signaling to lymphocyte adhesion and interactions.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- Phosphoinositide 3-kinases (PI3Ks) are central to lymphocyte activation through various receptors.
- Pleckstrin homology (PH) domains mediate PI3K-driven cellular responses.
- PH-domain containing adapter molecules link PI3K signaling to lymphocyte function.
Purpose of the Study:
- To review PI3K-regulated adapter proteins, focusing on the Bam32/DAPP/TAPP families.
- To elucidate the role of these adapters in lymphocyte activation and function.
- To define molecular interactions and functions of TAPP adapters.
Main Methods:
- Review of existing data on PI3K-regulated adapter proteins.
- Analysis of phosphoinositide-binding domains and their role in recruitment.
- Examination of protein complex assembly at the plasma membrane.
Main Results:
- Adapter recruitment to the plasma membrane is driven by PI3K-generated phosphoinositides (e.g., PIP3, PIP2).
- Bam32/DAPP1 and SKAPs activate GTPases, promoting integrin activation and lymphocyte adhesion.
- GAB proteins modulate PI3K signaling through amplification or inhibition.
Conclusions:
- Adapter proteins are key mediators of PI3K signaling in lymphocytes.
- These adapters assemble protein complexes that regulate lymphocyte adhesion and cell interactions.
- TAPP adapters are effectors of PIP2 and involved in lymphocyte adhesion.
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