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Phosphorylation and Activation of the DNA Binding Activity of Purified Stat1 by the Janus Protein-tyrosine Kinases and the Epidermal Growth Factor Receptor
- Source :
- Journal of Biological Chemistry. 270:20775-20780
- Publication Year :
- 1995
- Publisher :
- Elsevier BV, 1995.
-
Abstract
- The activation of Janus protein-tyrosine kinases (Jaks) and the subsequent phosphorylation and activation of latent signal transducers and activators of transcription (Stats) are common elements in signal transduction through the cytokine receptor superfamily. To assess the role and specificity of Jaks in Stat activation, we have utilized baculovirus expression systems to produce Stat1 and the Jaks. Co-expression of Stat1 with Tyk2, Jak1, or Jak2 resulted in the specific tyrosine phosphorylation of Stat1 at Tyr701, the residue phosphorylated in mammalian cells stimulated with interferon gamma. Alternatively, Stat1, purified to apparent homogeneity from insect cell extracts, was phosphorylated at Tyr701 in Jak immune complex kinase reactions. Phosphorylation of purified Stat1 was necessary and sufficient for the acquisition of DNA binding activity. The specificity in both systems was indicated by the inability of a Jak2 catalytically inactive mutant (Jak2-Glu882) or the Tec protein-tyrosine kinase to phosphorylate Stat1. However, immune complex-purified epidermal growth factor receptor was capable of phosphorylating purified Stat1 at Tyr701 and activating its DNA binding activity in in vitro reactions.
- Subjects :
- Phosphopeptides
Blotting, Western
Molecular Sequence Data
Spodoptera
Biology
Transfection
Peptide Mapping
Biochemistry
Cell Line
Mice
chemistry.chemical_compound
Growth factor receptor
Proto-Oncogene Proteins
Animals
Humans
Protein phosphorylation
Amino Acid Sequence
Phosphorylation
Molecular Biology
Mammals
TYK2 Kinase
Sheep
Sequence Homology, Amino Acid
Proteins
JAK-STAT signaling pathway
Tyrosine phosphorylation
Janus Kinase 1
Cell Biology
Janus Kinase 2
Protein-Tyrosine Kinases
Interleukin-13 receptor
Recombinant Proteins
DNA-Binding Proteins
ErbB Receptors
STAT1 Transcription Factor
chemistry
Protein Biosynthesis
Trans-Activators
Tyrosine
bacteria
Signal transduction
Janus kinase
Subjects
Details
- ISSN :
- 00219258
- Volume :
- 270
- Database :
- OpenAIRE
- Journal :
- Journal of Biological Chemistry
- Accession number :
- edsair.doi.dedup.....5864fed86e85f8abdc9c2bdd5cb1a18e