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Updated: Aug 17, 2026

A TIRF Microscopy Technique for Real-time, Simultaneous Imaging of the TCR and its Associated Signaling Proteins
16:10

A TIRF Microscopy Technique for Real-time, Simultaneous Imaging of the TCR and its Associated Signaling Proteins

Published on: March 22, 2012

Multiple kinases and signal transduction. Phosphorylation of the T cell antigen receptor complex

M D Patel, L E Samelson, R D Klausner

    The Journal of Biological Chemistry
    |April 25, 1987
    PubMed

    Insights

    Antigen receptor signaling involves complex kinase interactions. Protein kinase C and cyclic AMP-dependent protein kinase modulate serine and tyrosine phosphorylation events critical for T cell activation.

    Area of Science:

    • Immunology
    • Cell Biology
    • Biochemistry

    Background:

    • The T cell antigen receptor (TCR) is a multi-component complex crucial for adaptive immunity.
    • Kinase activity plays a pivotal role in TCR-mediated signal transduction pathways.

    Purpose of the Study:

    • To investigate the interplay of multiple kinases in TCR signaling.
    • To elucidate the roles of protein kinase C (PKC) and cyclic AMP-dependent protein kinase (PKA) in TCR-induced phosphorylation events.

    Main Methods:

    • Analysis of serine and tyrosine phosphorylation of TCR components.
    • Investigation of polyphosphoinositide metabolism and PKC activation.
    • Pharmacological manipulation of kinase activities using phorbol esters and PKA activators.

    Main Results:

    • Antigen stimulation induces serine phosphorylation of the gamma glycoprotein and tyrosine phosphorylation of p21, both associated with the TCR.
    • Tyrosine phosphorylation is dependent on kinase activation, while serine phosphorylation is linked to PKC activity.
    • PKC depletion dissociates phorbol ester-induced serine but not tyrosine phosphorylation.
    • PKA activation inhibits both serine and tyrosine phosphorylation, with modulation by PKC activators.

    Conclusions:

    • TCR signal transduction involves a complex network of interacting kinase activities.
    • Distinct kinases regulate specific phosphorylation events, highlighting a finely tuned signaling mechanism.
    • The balance between stimulatory and inhibitory kinase activities is essential for proper T cell receptor function.

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