Binding of interferon-α to the interferon-α/β receptor activates the tyrosine kinases Jak1 and Tyk2, and several members of the signal transducers and activator of transcription (STAT) transcription factor family. Su and David used a protein kinase inhibitor, piceatannol, to determine whether the tyrosine phosphorylation of specific STAT proteins is differentially regulated. Tyrosine phosphorylation of STAT3, STAT5, and Jak1 was piceatannol-sensitive, whereas tyrosine phosphorylation of STAT1, STAT2, and Tyk2 was piceatannol-resistant, suggesting that different kinases are responsible for regulating the activation of the STAT proteins in response to interferon-α.
Su, L., and David, M. (2000) Distinct mechanisms of STAT phosphorylation via the interferon-α/β receptor: Selective inhibition of STAT3 and STAT5 by piceatannol. J. Biol. Chem. 275: 12661-12666. [Abstract] [Full Text]
