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Time-resolved Förster Resonance Energy Transfer Assays for Measurement of Endogenous Phosphorylated STAT Proteins in Human Cells
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Published on: September 9, 2021

The Jak-STAT pathway stimulated by interferon alpha or interferon beta

Curt M Horvath1

  • 1Department of Medicine, Evanston Northwestern Healthcare Research Institute, IL 60208, USA. curt.horvath@mssm.edu <curt.horvath@mssm.edu>

Science'S STKE : Signal Transduction Knowledge Environment
|November 25, 2004
PubMed

Type I interferons, such as interferon alpha and interferon beta (IFN-alpha and beta), signal through a Janus kinase (Jak) to signal transduction and activator of transcription (STAT) pathway to stimulate gene expression. In response to ligand binding, the receptors dimerize, Jaks phosphorylate STAT1 and STAT2, which then dimerize and interact with a third transcriptional regulator IFN regulatory factor 9 (IRF9) to stimulate gene expression. IFN-alpha is the main innate antiviral cytokine and is essential for effective immune response to viral infection. The animation shows activation of STAT-responsive gene expression in response to type I IFNs.

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