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A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3
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A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3

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Meet the terminator: The phosphatase PP2A puts brakes on IRF-3 activation

Saurabh Chattopadhyay1, Ganes C Sen1

  • 1Department of Molecular Genetics, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.

Molecular Cell
|April 29, 2014
PubMed

Insights

Cellular interferon responses to infection are brief. Protein phosphatase 2A (PP2A) deactivates phospho-interferon regulatory factor 3, explaining why interferon synthesis is transient.

Area of Science:

  • Immunology
  • Cellular Biology
  • Molecular Biology

Background:

  • Cellular responses to microbial infection, particularly interferon production, are known to be transient.
  • The precise molecular mechanisms regulating the termination of these responses are not fully understood.

Purpose of the Study:

  • To identify key regulators responsible for the transient nature of the cellular interferon response.
  • To elucidate the role of specific protein phosphatases in modulating interferon synthesis.

Main Methods:

  • The study investigated the activity of protein phosphatase 2A (PP2A) in the context of interferon regulatory factor 3 (IRF3) phosphorylation.
  • Utilized molecular biology techniques to assess the dephosphorylation of phospho-IRF3 by PP2A.

Main Results:

  • Protein phosphatase 2A (PP2A) was identified as a crucial deactivator of phospho-interferon regulatory factor 3 (p-IRF3).
  • PP2A directly targets and removes the phosphate group from IRF3, a key transcription factor for interferon synthesis.
  • This deactivation mechanism provides a molecular basis for the transient induction of interferon.

Conclusions:

  • PP2A plays a critical role in terminating the cellular interferon response by deactivating p-IRF3.
  • The findings reveal a novel regulatory pathway controlling the duration of innate immune signaling.
  • Understanding this mechanism is vital for comprehending host defense dynamics during microbial infections.

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